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George SC, Tolakanahalli R, Aguirre S, Kim TP, Samuel EJJ, Mishra V. A single-institution experience with 177Lu RPT workflow improvements and qualifying the SPECT/CT imaging for dosimetry. Front Oncol 2024; 14:1331266. [PMID: 38469241 PMCID: PMC10925616 DOI: 10.3389/fonc.2024.1331266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 01/22/2024] [Indexed: 03/13/2024] Open
Abstract
Background and purpose Implementing any radiopharmaceutical therapy (RPT) program requires a comprehensive review of system readiness, appropriate workflows, and training to ensure safe and efficient treatment delivery. A quantitative assessment of the dose delivered to targets and organs at risk (OAR) using RPT is possible by correlating the absorbed doses with the delivered radioactivity. Integrating dosimetry into an established RPT program demands a thorough analysis of the necessary components and system fine-tuning. This study aims to report an optimized workflow for molecular radiation therapy using 177Lu with a primary focus on integrating patient-specific dosimetry into an established radiopharmaceutical program in a radiation oncology setting. Materials and methods We comprehensively reviewed using the Plan-Do-Check-Act (PDCA) cycle, including efficacy and accuracy of delivery and all aspects of radiation safety of the RPT program. The GE Discovery SPECT/CT 670DR™ system was calibrated per MIM protocol for dose calculation on MIM SurePlan™ MRT software. Jaszcak Phantom with 15-20 mCi of 177Lu DOTATATE with 2.5 µM EDTA solution was used, with the main energy window defined as 208 keV ±10% (187.6 to 229.2 keV); the upper scatter energy window was set to 240 keV ±5% (228 to 252 keV), while the lower scatter energy window was 177.8 keV ±5% (168.9 to 186.7 keV). Volumetric quality control tests and adjustments were performed to ensure the correct alignment of the table, NM, and CT gantry on SPECT/CT. A comprehensive end-to-end (E2E) test was performed to ensure workflow, functionality, and quantitative dose accuracy. Results Workflow improvements and checklists are presented after systematically analyzing over 400 administrations of 177Lu-based RPT. Injected activity to each sphere in the NEMA Phantom scan was quantified, and the MIM Sureplan MRT reconstruction images calculated activities within ±12% of the injected activity. Image alignment tests on the SPECT/CT showed a discrepancy of more than the maximum tolerance of 2.2 mm on any individual axis. As a result of servicing the machine and updating the VQC and COR corrections, the hybrid imaging system was adjusted to achieve an accuracy of <1 mm in all directions. Conclusion Workflows and checklists, after analysis of system readiness and adequate training for staff and patients, are presented. Hardware and software components for patient-specific dosimetry are presented with a focus on hybrid image registration and correcting any errors that affect dosimetric quantification calculation. Moreover, this manuscript briefly overviews the necessary quality assurance requirements for converting diagnostic images into dosimetry measurement tools and integrating dosimetry for RPT based on 177Lu.
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Affiliation(s)
- Siju C. George
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health, Miami, FL, United States
- Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, India
| | - Ranjini Tolakanahalli
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health, Miami, FL, United States
| | - Santiago Aguirre
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health, Miami, FL, United States
| | - Taehyung Peter Kim
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health, Miami, FL, United States
| | | | - Vivek Mishra
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health, Miami, FL, United States
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Yang C, Ko K, Lin P. Reducing scan time in 177 Lu planar scintigraphy using convolutional neural network: A Monte Carlo simulation study. J Appl Clin Med Phys 2023; 24:e14056. [PMID: 37261890 PMCID: PMC10562044 DOI: 10.1002/acm2.14056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/15/2022] [Accepted: 05/16/2023] [Indexed: 06/02/2023] Open
Abstract
PURPOSE The aim of this study was to reduce scan time in 177 Lu planar scintigraphy through the use of convolutional neural network (CNN) to facilitate personalized dosimetry for 177 Lu-based peptide receptor radionuclide therapy. METHODS The CNN model used in this work was based on DenseNet, and the training and testing datasets were generated from Monte Carlo simulation. The CNN input images (IMGinput ) consisted of 177 Lu planar scintigraphy that contained 10-90% of the total photon counts, while the corresponding full-count images (IMG100% ) were used as the CNN label images. Two-sample t-test was conducted to compare the difference in pixel intensities within region of interest between IMG100% and CNN output images (IMGoutput ). RESULTS No difference was found in IMGoutput for rods with diameters ranging from 13 to 33 mm in the Derenzo phantom with a target-to-background ratio of 20:1, while statistically significant differences were found in IMGoutput for the 10-mm diameter rods when IMGinput containing 10% to 60% of the total photon counts were denoised. Statistically significant differences were found in IMGoutput for both right and left kidneys in the NCAT phantom when IMGinput containing 10% of the total photon counts were denoised. No statistically significant differences were found in IMGoutput for any other source organs in the NCAT phantom. CONCLUSION Our results showed that the proposed method can reduce scan time by up to 70% for objects larger than 13 mm, making it a useful tool for personalized dosimetry in 177 Lu-based peptide receptor radionuclide therapy in clinical practice.
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Affiliation(s)
- Ching‐Ching Yang
- Department of Medical Imaging and Radiological SciencesKaohsiung Medical UniversityKaohsiungTaiwan
- Department of Medical ResearchKaohsiung Medical University Chung‐Ho Memorial HospitalKaohsiungTaiwan
| | - Kuan‐Yin Ko
- Department of Nuclear MedicineNational Taiwan University Cancer CenterTaipeiTaiwan
- Graduate Institute of Clinical MedicineCollege of MedicineNational Taiwan UniversityTaipeiTaiwan
| | - Pei‐Yao Lin
- Department of Nuclear MedicineNational Taiwan University Cancer CenterTaipeiTaiwan
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Pollard AC, de la Cerda J, Schuler FW, Kingsley CV, Gammon ST, Pagel MD. Evaluations of the performances of PET and MRI in a simultaneous PET/MRI instrument for pre-clinical imaging. EJNMMI Phys 2022; 9:70. [PMID: 36209262 PMCID: PMC9547760 DOI: 10.1186/s40658-022-00483-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/08/2022] [Indexed: 11/15/2022] Open
Abstract
Background PET/MRI is an attractive imaging modality due to the complementary nature of MRI and PET. Obtaining high quality small animal PET/MRI results is key for the translation of novel PET/MRI agents and techniques to the radiology clinic. To obtain high quality imaging results, a hybrid PET/MRI system requires additional considerations beyond the standard issues with separate PET and MRI systems. In particular, researchers must understand how their PET system affects the MR acquisitions and vice versa. Depending on the application, some of these effects may substantially influence image quality. Therefore, the goal of this report is to provide guidance, recommendations, and practical experiments for implementing and using a small animal PET/MRI instrument. Results Various PET and MR image quality parameters were tested with their respective modality alone and in the presence of both systems to determine how the combination of PET/MRI affects image quality. Corrections and calibrations were developed for many of these effects. While not all image characteristics were affected, some characteristics such as PET quantification, PET SNR, PET spatial resolution, PET partial volume effects, and MRI SNR were altered by the presence of both systems. Conclusions A full exploration of a new PET/MRI system before performing small animal PET/MRI studies is beneficial and necessary to ensure that the new instrument can produce highly accurate and precise PET/MR images. Supplementary Information The online version contains supplementary material available at 10.1186/s40658-022-00483-x.
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Affiliation(s)
- Alyssa C Pollard
- Department of Chemistry, Rice University, Houston, TX, USA.,Department of Cancer Systems Imaging, MD Anderson Cancer Center, Houston, TX, USA
| | - Jorge de la Cerda
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, Houston, TX, USA
| | - F William Schuler
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, Houston, TX, USA
| | - Charles V Kingsley
- Department of Imaging Physics, MD Anderson Cancer Center, Houston, TX, USA
| | - Seth T Gammon
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, Houston, TX, USA
| | - Mark D Pagel
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, Houston, TX, USA.
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Lin PY, Jhan KJ, Ko KY, Yang CC. Investigating the lesion detectability of Tc-99m planar scintigraphy acquired with LEHRS collimator for patients with different body sizes: A phantom study. J Appl Clin Med Phys 2022; 23:e13744. [PMID: 35946828 PMCID: PMC9588265 DOI: 10.1002/acm2.13744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 11/25/2022] Open
Abstract
Purpose The aim of this work was to investigate the lesion detectability of Tc‐99m planar scintigraphy acquired with a low‐energy high‐resolution and sensitivity (LEHRS) collimator and processed by Clarity 2D for patients with different body sizes through phantom study. Methods A NEMA IEC body phantom set was covered by two layers of 25‐mm‐thick bolus to construct phantom in three different sizes. All image data were performed on a Discovery NM/CT 870 DR with an LEHRS collimator and processed by Clarity 2D with blend ratio a of 0%, 20%, 40%, 60%, 80%, and 100%. The lesion detectability in gamma scintigraphy was evaluated by calculating the contrast‐to‐noise ratio (CNR). Multiple linear regression methods were used to analyze the impact of body size, target size, and Clarity 2D blending weight on the lesion detectability of Tc‐99m planar scintigraphy. Results It was found that changing the blend ratio could improve CNR, and this phenomenon was more significant in anterior view than in posterior view. Our results also suggested that the blend ratio should be selected according to patient body size in order to maintain consistent CNR. Hence, when a blend ratio of 60% was used for a patient before cancer treatment, a lower blend ratio should be used for the same patient experiencing treatment‐related weight loss to achieve consistent lesion detectability in Tc‐99m planar scintigraphy acquired with LEHRS and processed by Clarity 2D. Conclusion The magnitude of photon attenuation and scattering is higher in patients with larger body size, so Tc‐99m planar scintigraphy usually has lower lesion detectability in obese patients. Although photon attenuation and scattering are inevitable during image formation, their impacts on image quality can be eased by employing appropriate image protocol parameters.
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Affiliation(s)
- Pei-Yao Lin
- Department of Nuclear Medicine, National Taiwan University Cancer Center, Taipei, Taiwan, ROC
| | - Kai-Jie Jhan
- Department of Nuclear Medicine, National Yang-Ming University Hospital, Yilan, Taiwan, ROC
| | - Kuan-Yin Ko
- Department of Nuclear Medicine, National Taiwan University Cancer Center, Taipei, Taiwan, ROC.,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan. ROC
| | - Ching-Ching Yang
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC.,Department of Medical Research, Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung, Taiwan, ROC
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McArdle N, Cournane S, McCavana J, Lucey J, León Vintró L. Development of a scatter correction technique for planar 99mTc-MAA imaging to improve accuracy in lung shunt fraction estimation. Phys Med 2022; 99:94-101. [PMID: 35665625 DOI: 10.1016/j.ejmp.2022.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/26/2022] [Accepted: 05/27/2022] [Indexed: 10/18/2022] Open
Abstract
PURPOSE Prior to 90Y selective internal radiation therapy (SIRT) treatment, 99mTc-MAA scintigraphy imaging is used in the estimation of the lung shunt fraction (LSF). Planar imaging is recommended for determining a LSF ratio. However, the estimate may be affected by scatter contributions, attenuation and respiratory motion. The objective of this study was to correct for the effects of scatter in the LSF, towards the determination of a more accurate estimation method of LSF derived from planar scintigraphy imaging, which is recommended by international guidelines. METHODS The open access SIMIND Monte Carlo modelling software was used to estimate an optimum scatter window (SW) for scatter correction. The uncertainties associated with scatter and scatter contributions from the liver on the LSF were evaluated using an anthropomorphic thorax phantom and a virtual Vox-Man phantom. A brief retrospective examination of patient scans and tumour location investigated the impact that the inclusion of the simulated scatter corrections had on the LSF estimation. RESULTS The percentage overestimation of the manufacturer recommended method of LSF estimation was 192%. SW corrections improved the uncertainty to within 19% for the range of known LSFs. Similar findings were observed for our patient and tumour location studies. CONCLUSION The incorporated scatter corrections can significantly improve the accuracy of the LSF estimation, thereby providing a robust gamma camera, patient and tumour depth specific correction which is easily implementable. This is supported by Monte Carlo, phantom and preliminary patient studies.
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Affiliation(s)
- Niamh McArdle
- St. Vincent's University Hospital, Ireland; University College Dublin, Ireland.
| | - Seán Cournane
- St. Vincent's University Hospital, Ireland; University College Dublin, Ireland
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Park J, Oh D, Paeng JC, Lee M, Chung JW, Kim HC. Radioembolization for Hepatocellular Carcinoma: The Effects of Arterioportal Shunts on Nontargeted Liver Hypertrophy. J Vasc Interv Radiol 2022; 33:787-796.e4. [PMID: 35346860 DOI: 10.1016/j.jvir.2022.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 03/03/2022] [Accepted: 03/15/2022] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To determine whether arterioportal shunting to the contralateral lobe attenuates the liver function and the hypertrophy of the nontargeted liver after radioembolization in patients with hepatocellular carcinoma (HCC) MATERIALS AND METHODS: This retrospective study included 46 patients who received radioembolization for HCC contained within the right lobe between 2012 and 2020. The patients were divided into the following groups based on the presence and extent of arterioportal shunt : patients with retrograde arterioportal shunting to the left lobe (contralateral group) and patients with arterioportal shunt limited to the right lobe or no arterioportal shunt (control group). Safety profiles including adverse events, tumor response and overall survival were compared. With the volume of left lateral segment used as a surrogate marker for nontarget liver, degree of hypertrophy was compared between two groups at 3 and 6 months. RESULTS Liver function significantly deteriorated in contralateral group in a month (p=<0.05). Tumor response and overall survival did not significantly differ between two groups. Degree of hypertrophy was significantly higher in the control group compared with the contralateral group at 3 months [10.6% vs 3.5% (p = 0.008)] and at 6 months [20.7% vs 2.4% (p < 0.001)]. CONCLUSION In patients with arterioportal shunting to the contralateral lobe, hypertrophy of the nontarget liver may not occur and the liver function may be worsened.
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Affiliation(s)
- Juil Park
- Departments of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Dongkyu Oh
- Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Chul Paeng
- Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Myungsu Lee
- Departments of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Wook Chung
- Departments of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Hyo-Cheol Kim
- Departments of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
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Assessment of mouse-specific pharmacokinetics in kidneys based on 131I activity measurements using micro-SPECT. EJNMMI Phys 2022; 9:13. [PMID: 35195790 PMCID: PMC8866625 DOI: 10.1186/s40658-022-00443-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 02/10/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In order to acquire accurate drug pharmacokinetic information, which is required for tissue dosimetry, micro-SPECT must be quantitative to allow for an accurate assessment of radioligand activity in the relevant tissue. This study investigates the feasibility of deriving accurate mouse-specific time-integrated drug pharmacokinetic data in mouse kidneys from activity measurements using micro-SPECT. METHODS An animal experiment was carried out to evaluate the accuracy of 131I activity quantification in mouse kidneys (mean tissue volume of 0.140 mL) using a micro-SPECT system against conventional ex vivo gamma counting (GC) in a NaI(Tl) detector. The imaging setting investigated was that of the mouse biodistribution of a 131I-labelled single-domain antibody fragment (sdAb), currently being investigated for targeted radionuclide therapy of HER2-expressing cancer. SPECT imaging of 131I 365-keV photons was done with a VECTor/CT system (MILabs, Netherlands) using a high-energy mouse collimator with 1.6-mm-diameter pinholes. For both activity quantification techniques, the pharmacokinetic profile of the radioligand from approximately 1-73 h p.i. was derived and the time-integrated activity coefficient per gram of tissue (ã/M) was estimated. Additionally, SPECT activity recovery coefficients were determined in a phantom setting. RESULTS SPECT activities underestimate the reference activities by an amount that is dependent on the 131I activity concentration in the kidney, and thus on the time point of the pharmacokinetic profile. This underestimation is around - 12% at 1.5 h (2.89 MBq mL-1 mean reference activity concentration), - 13% at 6.6 h (149 kBq mL-1), - 40% at 24 h (17.6 kBq mL-1) and - 46% at 73 h (5.2 kBq mL-1) p.i. The ã/M value estimated from SPECT activities is, nevertheless, within - 14% from the reference (GC) ã/M value. Furthermore, better quantitative accuracy (within 2% from GC) in the SPECT ã/M value is achieved when SPECT activities are compensated for partial recovery with a phantom-based recovery coefficient of 0.85. CONCLUSION The SPECT imaging system used, together with a robust activity quantification methodology, allows an accurate estimation of time-integrated pharmacokinetic information of the 131I-labelled sdAb in mouse kidneys. This opens the possibility to perform mouse-specific kidney-tissue dosimetry based on pharmacokinetic data acquired in vivo on the same mice used in nephrotoxicity studies.
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Bin Said M, Abdul Razak H, Musarudin M. Does Single Computed Tomography Attenuation Correction able to Surrogate Serial Computed Tomography Attenuation Correction in Single-Photon Emission Computed Therapy Imaging for Peptide Receptor Radionuclide Therapy Dosimetry Result? J Med Phys 2022; 47:189-193. [PMID: 36212205 PMCID: PMC9543000 DOI: 10.4103/jmp.jmp_82_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 02/05/2022] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Peptide Receptor Radionuclide Therapy (PRRT) is the administration of a radionuclide, such as the Lu-177 label, along with a pharmaceutical agent to destroy the lesion cell. The first cycle of Lu-177 DOTA-TATE is an excellent way to estimate radionuclide uptake for organs at risk. To estimate the absorbed dose for a kidney, serial SPECT-CT imaging with up to five sets is required. In general, serial CT on patients would result in additional external exposure and extra time consuming, especially for low dose CT such as cone beam CT technology. However, by introducing a new method, such as optimized single CT (24 h) to perform with serial SPECT attenuation correction, additional external exposure from serial CT exposure could be reduced.
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Capala J, Graves SA, Scott A, Sgouros G, James SS, Zanzonico P, Zimmerman BE. Dosimetry for Radiopharmaceutical Therapy: Current Practices and Commercial Resources. J Nucl Med 2021; 62:3S-11S. [PMID: 34857621 DOI: 10.2967/jnumed.121.262749] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/22/2021] [Indexed: 11/16/2022] Open
Abstract
With the ongoing dramatic growth of radiopharmaceutical therapy, research and development in internal radiation dosimetry continue to advance both at academic medical centers and in industry. The basic paradigm for patient-specific dosimetry includes administration of a pretreatment tracer activity of the therapeutic radiopharmaceutical; measurement of its time-dependent biodistribution; definition of the pertinent anatomy; integration of the measured time-activity data to derive source-region time-integrated activities; calculation of the tumor, organ-at-risk, and/or whole-body absorbed doses; and prescription of the therapeutic administered activity. This paper provides an overview of the state of the art of patient-specific dosimetry for radiopharmaceutical therapy, including current methods and commercially available software and other resources.
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Affiliation(s)
| | | | - Aaron Scott
- Johns Hopkins University, Baltimore, Maryland
| | | | | | - Pat Zanzonico
- Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Brian E Zimmerman
- National Institute of Standards and Technology, Gaithersburg, Maryland
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Analysis of absorbed dose in radioimmunotherapy with 177Lu-trastuzumab using two different imaging scenarios: a pilot study. Nucl Med Commun 2021; 42:1382-1395. [PMID: 34406146 DOI: 10.1097/mnm.0000000000001472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Internal organ dosimetry is an important procedure to demonstrate the reliable application of 177Lu-trastuzumab radioimmunotherapy for human epidermal growth factor receptor-positive metastatic breast cancers. We are reporting the first human dosimetry study for 177Lu-trastuzumab. Another objective of our study was to calculate and compare the absorbed doses for normal organs and tumor lesions in patients before radioimmunotherapy with 177Lu-trastuzumab using two different imaging scenarios. METHODS Eleven patients (48.27 ± 8.95 years) with a history of metastatic breast cancer were included in the study. Postadministration of 177Lu-trastuzumab (351.09 ± 23.89 MBq/2 mg), acquisition was performed using planar and hybrid imaging scenarios at 4, 24, 72 and 168 h. Single-photon emission computed tomography/computed tomography imaging was performed at 72 h postinjection. Acquired images were processed using Dosimetry Toolkit software for the estimation of normalized cumulated activity in organs and tumor lesions. OLINDA/EXM 2.0 software was used for absorbed dose calculation in both scenarios. RESULTS Significant difference in normalized cumulated activity and the absorbed dose is noted between two imaging scenarios for the organs and tumor lesions (P < 0.05). Mean absorbed dose (mGy/MBq) estimated from heart, lungs, liver, spleen, kidney, adrenal, pancreas and colon using planar and hybrid scenarios were 0.81 ± 0.19 and 0.63 ± 0.17; 0.75 ± 0.13 and 0.32 ± 0.06; 1.26 ± 0.25 and 1.01 ± 0.17; 0.68 ± 0.22 and 0.53 ± 0.16; 0.91 ± 0.3 and 0.69 ± 0.24; 0.18 ± 0.04 and 0.11 ± 0.02; 0.25 ± 0.22 and 0.09 ± 0.02 and 0.75 ± 0.61 and 0.44 ± 0.28, respectively. CONCLUSIONS On the basis of our dosimetric evaluation, we concluded that radioimmunotherapy with 177Lu-trastuzumab is well tolerated to be implemented in routine clinical practice against HER2 positive metastatic breast cancer. Liver is the main critical organ at risk. Hybrid scenario demonstrated significantly lower absorbed doses in organs and tumors compared to the multiplanar method.
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Stolniceanu CR, Moscalu M, Azoicai D, Tamba B, Volovat C, Grierosu I, Ionescu T, Jalloul W, Ghizdovat V, Gherasim R, Volovat S, Wang F, Fu J, Moscalu R, Matovic M, Stefanescu C. Improved Personalised Neuroendocrine Tumours' Diagnosis Predictive Power by New Receptor Somatostatin Image Processing Quantification. J Pers Med 2021; 11:jpm11101042. [PMID: 34683183 PMCID: PMC8539645 DOI: 10.3390/jpm11101042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/28/2021] [Accepted: 10/13/2021] [Indexed: 11/24/2022] Open
Abstract
Although neuroendocrine tumours (NETs) are intensively studied, their diagnosis and consequently personalised therapy management is still puzzling due to their tumoral heterogeneity. In their theragnosis algorithm, receptor somatostatin scintigraphy takes the central place, the diagnosis receptor somatostatin analogue (RSA) choice depending on laboratory experience and accessibility. However, in all cases, the results depend decisively on correct radiotracer tumoral uptake quantification, where unfortunately there are still unrevealed clues and lack of standardization. We propose an improved method to quantify the biodistribution of gamma-emitting RSA, using tissular corrected uptake indices. We conducted a bi-centric retrospective study on 101 patients with different types of NETs. Three uptake indices obtained after applying new corrections to areas of interest drawn for the tumour and for three reference organs (liver, spleen and lung) were statistically analysed. For the corrected pathological uptake indices, the results showed a significant decrease in the error of estimating the occurrence of errors and an increase in the diagnostic predictive power for NETs, especially in the case of lung-referring corrected index. In conclusion, these results support the importance of corrected uptake indices use in the analysis of 99mTcRSA biodistribution for a better personalised diagnostic accuracy of NETs patients.
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Affiliation(s)
- Cati Raluca Stolniceanu
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Mihaela Moscalu
- Department of Preventive Medicine and Interdisciplinarity, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania
- Correspondence:
| | - Doina Azoicai
- Department of Epidemiology, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania;
| | - Bogdan Tamba
- Advanced Center for Research and Development in Experimental Medicine (CEMEX), “Grigore T. Popa” University of Medicine and Pharmacy, 700454 Iasi, Romania;
| | - Constantin Volovat
- Department of Medicine III—Medical Oncology-Radiotherapy, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.V.); (S.V.)
| | - Irena Grierosu
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Teodor Ionescu
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Wael Jalloul
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Vlad Ghizdovat
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Roxana Gherasim
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
| | - Simona Volovat
- Department of Medicine III—Medical Oncology-Radiotherapy, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.V.); (S.V.)
| | - Feng Wang
- Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China; (F.W.); (J.F.)
| | - Jingjing Fu
- Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China; (F.W.); (J.F.)
| | - Roxana Moscalu
- Manchester Academic Health Science Centre, School of Medical Sciences Manchester, The University of Manchester, Manchester M139PT, UK;
| | - Milovan Matovic
- Clinical Center Kragujevac, Center for Nuclear Medicine, Faculty of Medical Sciences, University of Kragujevac, 34000 Kragujevac, Serbia;
| | - Cipriana Stefanescu
- Department of Biophysics and Medical Physics-Nuclear Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (C.R.S.); (I.G.); (T.I.); (W.J.); (V.G.); (R.G.); (C.S.)
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Kiraga Ł, Kucharzewska P, Paisey S, Cheda Ł, Domańska A, Rogulski Z, Rygiel TP, Boffi A, Król M. Nuclear imaging for immune cell tracking in vivo – Comparison of various cell labeling methods and their application. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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13
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Morphis M, van Staden JA, du Raan H, Ljungberg M. Evaluation of Iodine-123 and Iodine-131 SPECT activity quantification: a Monte Carlo study. EJNMMI Phys 2021; 8:61. [PMID: 34410539 PMCID: PMC8377107 DOI: 10.1186/s40658-021-00407-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 08/10/2021] [Indexed: 01/18/2023] Open
Abstract
Purpose The quantitative accuracy of Nuclear Medicine images, acquired for both planar and SPECT studies, is influenced by the isotope-collimator combination as well as image corrections incorporated in the iterative reconstruction process. These factors can be investigated and optimised using Monte Carlo simulations. This study aimed to evaluate SPECT quantification accuracy for 123I with both the low-energy high resolution (LEHR) and medium-energy (ME) collimators and 131I with the high-energy (HE) collimator. Methods Simulated SPECT projection images were reconstructed using the OS-EM iterative algorithm, which was optimised for the number of updates, with appropriate corrections for scatter, attenuation and collimator detector response (CDR), including septal scatter and penetration compensation. An appropriate calibration factor (CF) was determined from four different source geometries (activity-filled: water-filled cylindrical phantom, sphere in water-filled (cold) cylindrical phantom, sphere in air and point-like source), investigated with different volume of interest (VOI) diameters. Recovery curves were constructed from recovery coefficients to correct for partial volume effects (PVEs). The quantitative method was evaluated for spheres in voxel-based digital cylindrical and patient phantoms. Results The optimal number of OS-EM updates was 60 for all isotope-collimator combinations. The CFpoint with a VOI diameter equal to the physical size plus a 3.0-cm margin was selected, for all isotope-collimator geometries. The spheres’ quantification errors in the voxel-based digital cylindrical and patient phantoms were less than 3.2% and 5.4%, respectively, for all isotope-collimator combinations. Conclusion The study showed that quantification errors of less than 6.0% could be attained, for all isotope-collimator combinations, if corrections for; scatter, attenuation, CDR (including septal scatter and penetration) and PVEs are performed. 123I LEHR and 123I ME quantification accuracies compared well when appropriate corrections for septal scatter and penetration were applied. This can be useful in departments that perform 123I studies and may not have access to ME collimators.
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Affiliation(s)
- Michaella Morphis
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa.
| | - Johan A van Staden
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
| | - Hanlie du Raan
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
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14
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van de Burgt A, Dibbets-Schneider P, Slump CH, Scholte AJHA, Atsma DE, de Geus-Oei LF, van Velden FHP. Experimental validation of absolute SPECT/CT quantification for response monitoring in patients with coronary artery disease. EJNMMI Phys 2021; 8:48. [PMID: 34132918 PMCID: PMC8208344 DOI: 10.1186/s40658-021-00393-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 06/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Quantitative SPECT enables absolute quantification of uptake in perfusion defects. The aim of this experimental study is to assess quantitative accuracy and precision of a novel iterative reconstruction technique (Evolution; GE Healthcare) for the potential application of response monitoring using 99mTc-tetrofosmin SPECT/CT in patients with coronary artery disease (CAD). METHODS Acquisitions of an anthropomorphic torso phantom with cardiac insert containing defects (with varying sizes), filled with 99mTc-pertechnetate, were performed on a SPECT/CT (Discovery 670 Pro, GE Healthcare). Subsequently, volumes of interest of the defects were manually drawn on CT to assess the recovery coefficient (RC). Bull's eye plots were composed to evaluate the uptake per segment. Finally, 99mTc-tetrofosmin SPECT/CT scans of 10 CAD patients were used to illustrate clinical application. RESULTS The phantom study indicated that Evolution showed convergence after 7 iterations and 10 subsets. The average repeatability deviation of all configurations was 2.91% and 3.15% (%SD mean) for filtered (Butterworth) and unfiltered data, respectively. The accuracy after post-filtering was lower compared to the unfiltered data with a mean (SD) RC of 0.63 (0.05) and 0.70 (0.07), respectively (p < 0.05). More artificial defects were found on Bull's eye plots created with the unfiltered data compared to filtered data. Eight out of ten patients showed significant changes in uptake before and after treatment (p < 0.05). CONCLUSION Quantification of 99mTc-tetrofosmin SPECT/CT seems feasible for CAD patients when 7 iterations (10 subsets), Butterworth post-filtering (cut off frequency 0.52 in cycles/cm, order of 5) and manual CT-delineation are applied. However, future prospective patient studies are required for clinical application.
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Affiliation(s)
- Alina van de Burgt
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands.
| | - Petra Dibbets-Schneider
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | - Cornelis H Slump
- Technical Medical Center, University of Twente, Enschede, The Netherlands
| | - Arthur J H A Scholte
- Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Douwe E Atsma
- Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Lioe-Fee de Geus-Oei
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands.,Biomedical Photonic Imaging Group, University of Twente, Enschede, The Netherlands
| | - Floris H P van Velden
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
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15
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Mincke J, Courtyn J, Vanhove C, Vandenberghe S, Steppe K. Guide to Plant-PET Imaging Using 11CO 2. FRONTIERS IN PLANT SCIENCE 2021; 12:602550. [PMID: 34149742 PMCID: PMC8206809 DOI: 10.3389/fpls.2021.602550] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 05/03/2021] [Indexed: 05/12/2023]
Abstract
Due to its high sensitivity and specificity for tumor detection, positron emission tomography (PET) has become a standard and widely used molecular imaging technique. Given the popularity of PET, both clinically and preclinically, its use has been extended to study plants. However, only a limited number of research groups worldwide report PET-based studies, while we believe that this technique has much more potential and could contribute extensively to plant science. The limited application of PET may be related to the complexity of putting together methodological developments from multiple disciplines, such as radio-pharmacology, physics, mathematics and engineering, which may form an obstacle for some research groups. By means of this manuscript, we want to encourage researchers to study plants using PET. The main goal is to provide a clear description on how to design and execute PET scans, process the resulting data and fully explore its potential by quantification via compartmental modeling. The different steps that need to be taken will be discussed as well as the related challenges. Hereby, the main focus will be on, although not limited to, tracing 11CO2 to study plant carbon dynamics.
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Affiliation(s)
- Jens Mincke
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
- MEDISIP - INFINITY - IBiTech, Department of Electronics and Information Systems, Faculty of Engineering and Architecture, Ghent University, Ghent, Belgium
| | - Jan Courtyn
- Medical Molecular Imaging and Therapy, Department of Radiology and Nuclear Medicine, Ghent University Hospital, Ghent, Belgium
| | - Christian Vanhove
- MEDISIP - INFINITY - IBiTech, Department of Electronics and Information Systems, Faculty of Engineering and Architecture, Ghent University, Ghent, Belgium
| | - Stefaan Vandenberghe
- MEDISIP - INFINITY - IBiTech, Department of Electronics and Information Systems, Faculty of Engineering and Architecture, Ghent University, Ghent, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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Hooijman EL, Chalashkan Y, Ling SW, Kahyargil FF, Segbers M, Bruchertseifer F, Morgenstern A, Seimbille Y, Koolen SLW, Brabander T, de Blois E. Development of [ 225Ac]Ac-PSMA-I&T for Targeted Alpha Therapy According to GMP Guidelines for Treatment of mCRPC. Pharmaceutics 2021; 13:pharmaceutics13050715. [PMID: 34068206 PMCID: PMC8153125 DOI: 10.3390/pharmaceutics13050715] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/03/2021] [Accepted: 05/06/2021] [Indexed: 12/22/2022] Open
Abstract
Recently, promising results of the antitumor effects were observed in patients with metastatic castration-resistant prostate cancer treated with 177Lu-labeled PSMA-ligands. Radionuclide therapy efficacy may even be improved by using the alpha emitter Ac-225. Higher efficacy is claimed due to high linear energy transfer specifically towards PSMA positive cells, causing more double-strand breaks. This study aims to manufacture [225Ac]Ac-PSMA-I&T according to good manufacturing practice guidelines for the translation of [225Ac]Ac-PSMA-I&T into a clinical phase 1 dose escalation study. Quencher addition during labeling was investigated. Quality control of [225Ac]Ac-PSMA-I&T was based on measurement of Fr-221 (218 keV), in equilibrium with Ac-225 in approximately six half-lives of Fr-221 (T½ = 4.8 min). Radio-(i)TLC methods were utilized for identification of the different radiochemical forms, gamma counter for concentration determination, and HPGe-detector for the detection of the radiochemical yield. Radiochemical purity was determined by HPLC. The final patient dose was prepared and diluted with an optimized concentration of quenchers as during labeling, with an activity of 8–12 MBq (±5%), pH > 5.5, 100 ± 20 μg/dose, PSMA-I&T, radiochemical yield >95%, radiochemical purity >90% (up to 3 h), endotoxin levels of <5 EU/mL, osmolarity of 2100 mOsmol, and is produced according to current guidelines. The start of the phase I dose escalation study is planned in the near future.
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Affiliation(s)
- Eline L. Hooijman
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
- Erasmus Medical Centre, Department of Pharmacy, 3015 CN Rotterdam, The Netherlands
| | - Yozlem Chalashkan
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
| | - Sui Wai Ling
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
| | - Figen F. Kahyargil
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
- Erasmus Medical Centre, Department of Pharmacy, 3015 CN Rotterdam, The Netherlands
| | - Marcel Segbers
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
| | - Frank Bruchertseifer
- Joint Research Centre, European Commission, 76344 Karlsruhe, Germany; (F.B.); (A.M.)
| | - Alfred Morgenstern
- Joint Research Centre, European Commission, 76344 Karlsruhe, Germany; (F.B.); (A.M.)
| | - Yann Seimbille
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
- Division of Life Sciences, TRIUMF, Vancouver, BC V6T 2A3, Canada
| | - Stijn L. W. Koolen
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
- Erasmus Medical Centre, Department of Pharmacy, 3015 CN Rotterdam, The Netherlands
- Department of Medical Oncology, Erasmus MC Cancer Institute, 3015 CN Rotterdam, The Netherlands
| | - Tessa Brabander
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
| | - Erik de Blois
- Erasmus Medical Centre, Department of Radiology and Nuclear Medicine, 3015 CN Rotterdam, The Netherlands; (E.L.H.); (Y.C.); (S.W.L.); (F.F.K.); (M.S.); (Y.S.); (S.L.W.K.); (T.B.)
- Correspondence: ; Tel.: +31-107035317
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Ramonaheng K, van Staden JA, du Raan H. The effect of calibration factors and recovery coefficients on 177Lu SPECT activity quantification accuracy: a Monte Carlo study. EJNMMI Phys 2021; 8:27. [PMID: 33738605 PMCID: PMC7973313 DOI: 10.1186/s40658-021-00365-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 02/08/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Different gamma camera calibration factor (CF) geometries have been proposed to convert SPECT data into units of activity concentration. However, no consensus has been reached on a standardised geometry. The CF is dependent on the selected geometry and is further affected by partial volume effects. This study investigated the effect of two CF geometries and their corresponding recovery coefficients (RCs) on the quantification accuracy of 177Lu SPECT images using Monte Carlo simulations. METHODS The CF geometries investigated were (i) a radioactive-sphere surrounded by non-radioactive water (sphere-CF) and (ii) a cylindrical phantom uniformly filled with radioactive water (cylinder-CF). Recovery coefficients were obtained using the sphere-CF and cylinder-CF, yielding the sphere-RC and cylinder-RC values, respectively, for partial volume correction (PVC). The quantification accuracy was evaluated using four different-sized spheres (15.6-65.4 ml) and a kidney model with known activity concentrations inside a cylindrical, torso and patient phantom. Images were reconstructed with the 3D OS-EM algorithm incorporating attenuation, scatter and detector-response corrections. Segmentation was performed using the physical size and a small cylindrical volume inside the cylinder for the sphere-CF and cylinder-CF, respectively. RESULTS The sphere quantification error (without PVC) was better for the sphere-CF (≤ - 5.54%) compared to the cylinder-CF (≤ - 20.90%), attributed to the similar geometry of the quantified and CF spheres. Partial volume correction yielded comparable results for the sphere-CF-RC (≤ 3.47%) and cylinder-CF-RC (≤ 3.53%). The accuracy of the kidney quantification was poorer (≤ 22.34%) for the sphere-CF without PVC compared to the cylinder-CF (≤ 2.44%). With PVC, the kidney quantification results improved and compared well for the sphere-CF-RC (≤ 3.50%) and the cylinder-CF-RC (≤ 3.45%). CONCLUSION The study demonstrated that upon careful selection of CF-RC combinations, comparable quantification errors (≤ 3.53%) were obtained between the sphere-CF-RC and cylinder-CF-RC, when all corrections were applied.
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Affiliation(s)
- Keamogetswe Ramonaheng
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa.
| | - Johannes A van Staden
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
| | - Hanlie du Raan
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
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Halim F, Yahya H, Jaafar KN, Mansor S. Accuracy Assessment of SUV Measurements in SPECT/CT: A Phantom Study. J Nucl Med Technol 2021; 49:250-255. [PMID: 33722927 DOI: 10.2967/jnmt.120.259168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
Advances in iterative image reconstruction enable absolute quantification of SPECT/CT studies by incorporating compensations for collimator-detector response, attenuation, and scatter. This study aimed to assess the quantitative accuracy of SPECT/CT based on different levels of 99mTc activity (low/high) using different SUV metrics (SUVmean, SUVmax, SUV0.6 max, and SUV0.75 max [the average values that include pixels greater than 60% and 75% of the SUVmax in the volume of interest, respectively]). Methods: A Jaszczak phantom equipped with 6 fillable spheres was set up with low and high activity ratios of 1:4 and 1:10 (background-to-sphere) on background activities of 10 and 60 kBq/mL, respectively. The fixed-size volume of interest based on the diameter of each sphere was drawn on SPECT images using various metrics for SUV quantification purposes. Results: The convergence of activity concentration was dependent on the number of iterations and application of postfiltering. For the background-to-sphere ratio of 1:10 with a low background activity concentration, the SUVmean metric showed an underestimation of about 38% from the actual SUV, and SUVmax exhibited an overestimation of about 24% for the largest sphere diameter. Meanwhile, bias reductions of as much as -6% and -7% for SUV0.6 max and SUV0.75 max, respectively, were observed. SUVmax gave a more accurate reading than the others, although points that exceeded the actual value were detected. At 1:4 and 1:10 background activity of 10 kBq/mL, a low activity concentration attained a value close to the actual ratio. Use of 2 iterations and 10 subsets without postfiltering gave the most accurate values for reconstruction and the best image overall. Conclusion: SUVmax is the best metric in a high- or low-contrast-ratio phantom with at least 2 iterations, 10 subsets, and no postfiltering.
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Affiliation(s)
- Fatin Halim
- Oncological and Radiological Science Cluster, Advanced Medical and Dental Institute, SAINS@BERTAM, Universiti Sains Malaysia, Penang, Malaysia.,Department of Nuclear Medicine, Penang Hospital, Penang, Malaysia; and
| | - Hizwan Yahya
- Oncological and Radiological Science Cluster, Advanced Medical and Dental Institute, SAINS@BERTAM, Universiti Sains Malaysia, Penang, Malaysia.,Department of Nuclear Medicine, Penang Hospital, Penang, Malaysia; and
| | - Khairul Nizam Jaafar
- Nuclear Medicine Unit, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
| | - Syahir Mansor
- Oncological and Radiological Science Cluster, Advanced Medical and Dental Institute, SAINS@BERTAM, Universiti Sains Malaysia, Penang, Malaysia; .,Nuclear Medicine Unit, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Penang, Malaysia
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Tumor-to-Normal Ratio Relationship between Planning Technetium-99 Macroaggregated Albumin and Posttherapy Yttrium-90 Bremsstrahlung SPECT/CT. J Vasc Interv Radiol 2021; 32:752-760. [PMID: 33642158 DOI: 10.1016/j.jvir.2020.12.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/25/2020] [Accepted: 12/27/2020] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To quantify the relationship of the tumor-to-normal ratio (TNR) attained from the technetium-99m macroaggregated albumin (MAA) and posttreatment yttrium-90 bremsstrahlung (Y90-Brem) single-photon emission computerized tomography (SPECT)/computer tomography (CT) studies in patients with hepatocellular carcinoma (HCC) treated with glass microspheres. MATERIALS AND METHODS Retrospectively, a total of 190 consecutive patients with HCC who underwent 204 MAA and Y90-Brem SPECT/CT for glass microsphere Y90 radiation segmentectomy (Y90-RS) or lobar treatment (Y90-RLT) between 2013 and 2018 were included. Semi-automated regions-of-interests were drawn around the targeted tumor and nontumoral liver tissue on the SPECT/CT studies. TNR values from MAA and Y90-Brem SPECT/CT were compared using paired t-tests, Pearson correlation, and median with interquartile ranges (IQR). RESULTS The mean TNR for MAA and Y90-Brem SPECT/CT was 2.96 ± 1.86 (median, 2.64; IQR, 2.50) and 2.29 ± 1.10 (median, 2.06; IQR, 1.05), respectively (P < .0001). The mean Y90-RLT TNR was 2.88 ± 1.67 (median, 2.59; IQR, 0.83) and 2.17 ± 0.89 (median, 1.98; IQR, 0.81) for MAA and Y90-Brem SPECT/CT, respectively (P < .0001). The mean Y90-RS TNR was 3.02 ± 2.01 (median, 2.87; IQR, 3.01) and 2.39 ± 1.25 (median, 2.11; IQR, 1.28) for MAA and Y90-Brem SPECT/CT, respectively (P = .0003). TNR attained from MAA and Y90 SPECT/CT studies showed a moderate correlation in a positive linear fashion for the overall (r = 0.54; P < .001), Y90-RLT (r = 0.66, P < .001), and Y90-RS cohorts (r = 0.48, P < .001). CONCLUSIONS The TNR attained from Y90-Brem SPECT/CT is often underestimated, positively correlated, and less variable than that attained from MAA SPECT/CT.
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Abstract
Positron emission tomography (PET) is a non-invasive imaging technology employed to describe metabolic, physiological, and biochemical processes in vivo. These include receptor availability, metabolic changes, neurotransmitter release, and alterations of gene expression in the brain. Since the introduction of dedicated small-animal PET systems along with the development of many novel PET imaging probes, the number of PET studies using rats and mice in basic biomedical research tremendously increased over the last decade. This article reviews challenges and advances of quantitative rodent brain imaging to make the readers aware of its physical limitations, as well as to inspire them for its potential applications in preclinical research. In the first section, we briefly discuss the limitations of small-animal PET systems in terms of spatial resolution and sensitivity and point to possible improvements in detector development. In addition, different acquisition and post-processing methods used in rodent PET studies are summarized. We further discuss factors influencing the test-retest variability in small-animal PET studies, e.g., different receptor quantification methodologies which have been mainly translated from human to rodent receptor studies to determine the binding potential and changes of receptor availability and radioligand affinity. We further review different kinetic modeling approaches to obtain quantitative binding data in rodents and PET studies focusing on the quantification of endogenous neurotransmitter release using pharmacological interventions. While several studies have focused on the dopamine system due to the availability of several PET tracers which are sensitive to dopamine release, other neurotransmitter systems have become more and more into focus and are described in this review, as well. We further provide an overview of latest genome engineering technologies, including the CRISPR/Cas9 and DREADD systems that may advance our understanding of brain disorders and function and how imaging has been successfully applied to animal models of human brain disorders. Finally, we review the strengths and opportunities of simultaneous PET/magnetic resonance imaging systems to study drug-receptor interactions and challenges for the translation of PET results from bench to bedside.
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21
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Marquis H, Deidda D, Gillman A, Willowson KP, Gholami Y, Hioki T, Eslick E, Thielemans K, Bailey DL. Theranostic SPECT reconstruction for improved resolution: application to radionuclide therapy dosimetry. EJNMMI Phys 2021; 8:16. [PMID: 33598750 PMCID: PMC7889770 DOI: 10.1186/s40658-021-00362-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 02/02/2021] [Indexed: 12/20/2022] Open
Abstract
Background SPECT-derived dose estimates in tissues of diameter less than 3× system resolution are subject to significant losses due to the limited spatial resolution of the gamma camera. Incorporating resolution modelling (RM) into the SPECT reconstruction has been proposed as a possible solution; however, the images produced are prone to noise amplification and Gibbs artefacts. We propose a novel approach to SPECT reconstruction in a theranostic setting, which we term SPECTRE (single photon emission computed theranostic reconstruction); using a diagnostic PET image, with its superior resolution, to guide the SPECT reconstruction of the therapeutic equivalent. This report demonstrates a proof in principle of this approach. Methods We have employed the hybrid kernelised expectation maximisation (HKEM) algorithm implemented in STIR, with the aim of producing SPECT images with PET-equivalent resolution. We demonstrate its application in both a dual 68Ga/177Lu IEC phantom study and a clinical example using 64Cu/67Cu. Results SPECTRE is shown to produce images comparable in accuracy and recovery to PET with minimal introduction of artefacts and amplification of noise. Conclusion The SPECTRE approach to image reconstruction shows improved quantitative accuracy with a reduction in noise amplification. SPECTRE shows great promise as a method of improving SPECT radioactivity concentrations, directly leading to more accurate dosimetry estimates in small structures and target lesions. Further investigation and optimisation of the algorithm parameters is needed before this reconstruction method can be utilised in a clinical setting.
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Affiliation(s)
- H Marquis
- Sydney Vital Translational Cancer Research Centre, Sydney, Australia.,Institute of Medical Physics, University of Sydney, Sydney, Australia
| | - D Deidda
- National Physical Laboratory, Teddington, UK
| | - A Gillman
- Australian e-Health Research Centre, CSIRO, Brisbane, Australia
| | - K P Willowson
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
| | - Y Gholami
- Sydney Vital Translational Cancer Research Centre, Sydney, Australia.,Institute of Medical Physics, University of Sydney, Sydney, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - T Hioki
- Institute of Medical Physics, University of Sydney, Sydney, Australia
| | - E Eslick
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
| | - K Thielemans
- Institute of Nuclear Medicine, University College London, London, UK
| | - D L Bailey
- Sydney Vital Translational Cancer Research Centre, Sydney, Australia. .,Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia. .,Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
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22
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Markiewicz PJ, Matthews JC, Ashburner J, Cash DM, Thomas DL, De Vita E, Barnes A, Cardoso MJ, Modat M, Brown R, Thielemans K, da Costa-Luis C, Lopes Alves I, Gispert JD, Schmidt ME, Marsden P, Hammers A, Ourselin S, Barkhof F. Uncertainty analysis of MR-PET image registration for precision neuro-PET imaging. Neuroimage 2021; 232:117821. [PMID: 33588030 PMCID: PMC8204268 DOI: 10.1016/j.neuroimage.2021.117821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/25/2020] [Accepted: 01/21/2021] [Indexed: 10/29/2022] Open
Abstract
Accurate regional brain quantitative PET measurements, particularly when using partial volume correction, rely on robust image registration between PET and MR images. We argue here that the precision, and hence the uncertainty, of MR-PET image registration is mainly driven by the registration implementation and the quality of PET images due to their lower resolution and higher noise compared to the structural MR images. We propose a dedicated uncertainty analysis for quantifying the precision of MR-PET registration, centred around the bootstrap resampling of PET list-mode events to generate multiple PET image realisations with different noise (count) levels. The effects of PET image reconstruction parameters, such as the use of attenuation and scatter corrections and different number of iterations, on the precision and accuracy of MR-PET registration were investigated. In addition, the performance of four software packages with their default settings for rigid inter-modality image registration were considered: NiftyReg, Vinci, FSL and SPM. Four distinct PET image distributions made of two early time frames (similar to cortical FDG) and two late frames using two amyloid PET dynamic acquisitions of one amyloid positive and one amyloid negative participants were investigated. For the investigated four PET frames, the biggest impact on the uncertainty was observed between registration software packages (up to 10-fold difference in precision) followed by the reconstruction parameters. On average, the lowest uncertainty for different PET frames and brain regions was observed with SPM and two iterations of fully quantitative image reconstruction. The observed uncertainty for the varying PET count-level (from 5% to 60%) was slightly lower than for the reconstruction parameters. We also observed that the registration uncertainty in quantitative PET analysis depends on amyloid status of the considered PET frames, with increased uncertainty (up to three times) when using post-reconstruction partial volume correction. This analysis is applicable for PET data obtained from either PET/MR or PET/CT scanners.
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Affiliation(s)
- Pawel J Markiewicz
- Centre for Medical Image Computing; Department of Medical Physics and Biomedical Engineering, University College London Gower Street WC1E 6BT, London, UK; School of Biomedical Engineering and Imaging Sciences, King's College London, UK. http://www.nmi.cs.ucl.ac.uk
| | - Julian C Matthews
- Division of Neuroscience & Experimental Psychology, University of Manchester, UK
| | - John Ashburner
- Wellcome Centre for Human Neuroimaging, Queen Square Institute of Neurology, University College London, UK
| | - David M Cash
- Dementia Research Centre, Queen Square Institute of Neurology, University College London, UK
| | - David L Thomas
- Wellcome Centre for Human Neuroimaging, Queen Square Institute of Neurology, University College London, UK; Dementia Research Centre, Queen Square Institute of Neurology, University College London, UK
| | - Enrico De Vita
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Anna Barnes
- Institute of Nuclear Medicine, University College London, London, UK
| | - M Jorge Cardoso
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Marc Modat
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Richard Brown
- Institute of Nuclear Medicine, University College London, London, UK
| | - Kris Thielemans
- Institute of Nuclear Medicine, University College London, London, UK
| | - Casper da Costa-Luis
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Centre for Medical Image Computing; Department of Medical Physics and Biomedical Engineering, University College London Gower Street WC1E 6BT, London, UK
| | - Isadora Lopes Alves
- Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Radiology and Nuclear Medicine, Amsterdam, Netherlands
| | - Juan Domingo Gispert
- Barcelonaßeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | | | - Paul Marsden
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Alexander Hammers
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Sebastien Ourselin
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Frederik Barkhof
- Centre for Medical Image Computing; Department of Medical Physics and Biomedical Engineering, University College London Gower Street WC1E 6BT, London, UK; Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Radiology and Nuclear Medicine, Amsterdam, Netherlands
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Morphis M, van Staden JA, du Raan H, Ljungberg M. Modelling of energy-dependent spectral resolution for SPECT Monte Carlo simulations using SIMIND. Heliyon 2021; 7:e06097. [PMID: 33659726 PMCID: PMC7892923 DOI: 10.1016/j.heliyon.2021.e06097] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/22/2020] [Accepted: 01/21/2021] [Indexed: 12/29/2022] Open
Abstract
PURPOSE Monte Carlo (MC) modelling techniques have been used extensively in Nuclear Medicine (NM). The theoretical energy resolution relationship ( ∝ 1 / E ), does not accurately predict the gamma camera detector response across all energies. This study aimed to validate the accuracy of an energy resolution model for the SIMIND MC simulation code emulating the Siemens Symbia T16 dual-head gamma camera. METHODS Measured intrinsic energy resolution data (full width half maximum (FWHM) values), for Ba-133, Lu-177, Am-241, Ga-67, Tc-99m, I-123, I-131 and F-18 sources in air, were used to create a fitted model of the energy response of the gamma camera. Both the fitted and theoretical models were used to simulate intrinsic and extrinsic energy spectra using three different scenarios (source in air; source in simple scatter phantom and a clinical voxel-based digital patient phantom). RESULTS The results showed the theoretical model underestimated the FWHM values at energies above 160.0 keV up to 23.5 keV. In contrast, the fitted model better predicted the measured FWHM values with differences less than 3.3 keV. The I-131 in-scatter energy spectrum simulated with the fitted model better matched the measured energy spectrum. Higher energy photopeaks, (I-123: 528.9 keV and I-131: 636.9 keV) simulated with the fitted model, more accurately resembled the measured photopeaks. The voxel-based digital patient phantom energy spectra, simulated with the fitted and theoretical models, showed the potential impact of an incorrect energy resolution model when simulating isotopes with multiple photopeaks. CONCLUSION Modelling of energy resolution with the proposed fitted model enables the SIMIND user to accurately simulate NM images. A great improvement was seen for high-energy photon emitting isotopes (e.g. I-131), as well as isotopes with multiple photopeaks (e.g. Lu-177, I-131 and Ga-67) in comparison to the theoretical model. This will result in accurate evaluation of radioactivity quantification, which is vital for dosimetric purposes.
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Affiliation(s)
- Michaella Morphis
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Johan A. van Staden
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Hanlie du Raan
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Michael Ljungberg
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
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24
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Poulie CBM, Jørgensen JT, Shalgunov V, Kougioumtzoglou G, Jeppesen TE, Kjaer A, Herth MM. Evaluation of [ 64Cu]Cu-NOTA-PEG 7-H-Tz for Pretargeted Imaging in LS174T Xenografts-Comparison to [ 111In]In-DOTA-PEG 11-BisPy-Tz. Molecules 2021; 26:544. [PMID: 33494416 PMCID: PMC7865927 DOI: 10.3390/molecules26030544] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 02/07/2023] Open
Abstract
Pretargeted nuclear imaging for the diagnosis of various cancers is an emerging and fast developing field. The tetrazine ligation is currently considered the most promising reaction in this respect. Monoclonal antibodies are often the preferred choice as pretargeting vector due to their outstanding targeting properties. In this work, we evaluated the performance of [64Cu]Cu-NOTA-PEG7-H-Tz using a setup we previously used for [111In]In-DOTA-PEG11-BisPy-Tz, thereby allowing for comparison of the performance of these two promising pretargeting imaging agents. The evaluation included a comparison of the physicochemical properties of the compounds and their performance in an ex vivo blocking assay. Finally, [64Cu]Cu-NOTA-PEG7-H-Tz was evaluated in a pretargeted imaging study and compared to [111In]In-DOTA-PEG11-BisPy-Tz. Despite minor differences, this study indicated that both evaluated tetrazines are equally suited for pretargeted imaging.
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Affiliation(s)
- Christian B. M. Poulie
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; (C.B.M.P.); (V.S.); (G.K.)
| | - Jesper T. Jørgensen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; (J.T.J.); (T.E.J.)
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Vladimir Shalgunov
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; (C.B.M.P.); (V.S.); (G.K.)
| | - Georgios Kougioumtzoglou
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; (C.B.M.P.); (V.S.); (G.K.)
| | - Troels Elmer Jeppesen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; (J.T.J.); (T.E.J.)
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; (J.T.J.); (T.E.J.)
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Matthias M. Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; (C.B.M.P.); (V.S.); (G.K.)
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; (J.T.J.); (T.E.J.)
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Piron L, Deshayes E, Cassinotto C, Quenet F, Panaro F, Hermida M, Allimant C, Assenat E, Pageaux GP, Molinari N, Guiu B. Deportalization, Venous Congestion, Venous Deprivation: Serial Measurements of Volumes and Functions on Morphofunctional 99mTc-Mebrofenin SPECT-CT. Diagnostics (Basel) 2020; 11:diagnostics11010012. [PMID: 33374810 PMCID: PMC7823835 DOI: 10.3390/diagnostics11010012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/13/2020] [Accepted: 12/21/2020] [Indexed: 02/08/2023] Open
Abstract
The objective was to assess the changes in regional volumes and functions under venous-impaired vascular conditions following liver preparation. Twelve patients underwent right portal vein embolization (PVE) (n = 5) or extended liver venous deprivation (eLVD, i.e., portal and right and middle hepatic veins embolization) (n = 7). Volume and function measurements of deportalized liver, venous-deprived liver and congestive liver were performed before and after PVE/eLVD at days 7, 14 and 21 using 99mTc-mebrofenin hepatobiliary scintigraphy with single-photon emission computed tomography and computed tomography (99mTc-mebrofenin SPECT-CT). Volume and function progressed independently in the deportalized liver (p = 0.47) with an early decrease in function (median −18.2% (IQR, −19.4–−14.5) at day 7) followed by a decrease in volume (−19.3% (−22.6–−14.4) at day 21). Volume and function progressed independently in the venous deprived liver (p = 0.80) with a marked and early decrease in function (−41.1% (−52.0–−12.9) at day 7) but minimal changes in volume (−4.7% (−10.4–+3.9) at day 21). Volume and function progressed independently in the congestive liver (p = 0.21) with a gradual increase in volume (+43.2% (+38.3–+51.2) at day 21) that preceded a late and moderate increase in function at day 21 (+34.8% (−8.3–+46.6)), concomitantly to the disappearance of hypoattenuated congestive areas in segment IV (S4) on CT, initially observed in 6/7 patients after eLVD and represented 35.3% (22.2–46.4) of whole S4 volume. Liver volume and function progress independently whatever the vascular condition. Hepatic congestion from outflow obstruction drives volume increase but results in early impaired function.
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Affiliation(s)
- Lauranne Piron
- Department of Radiology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France; (C.C.); (M.H.); (C.A.); (B.G.)
- Correspondence:
| | - Emmanuel Deshayes
- Department of Nuclear Medicine, Cancer Institute of Montpellier (ICM), 34090 Montpellier, France;
- Institute of Research Cancer of Montpellier (IRCM), INSERM U1194, Montpellier University, Cancer Institute of Montpellier (ICM), 34090 Montpellier, France
| | - Christophe Cassinotto
- Department of Radiology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France; (C.C.); (M.H.); (C.A.); (B.G.)
| | - François Quenet
- Department of Surgical Oncology, Cancer Institute of Montpellier (ICM), 34090 Montpellier, France;
| | - Fabrizio Panaro
- Division of HBP Surgery and Transplantation, Department of Surgery, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France;
| | - Margaux Hermida
- Department of Radiology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France; (C.C.); (M.H.); (C.A.); (B.G.)
| | - Carole Allimant
- Department of Radiology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France; (C.C.); (M.H.); (C.A.); (B.G.)
| | - Eric Assenat
- Department of Oncology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France;
| | - Georges-Philippe Pageaux
- Department of Hepatology and Liver Transplantation, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France;
| | - Nicolas Molinari
- IMAG, CNRS, University of Montpellier, Montpellier University Hospital, 34090 Montpellier, France;
| | - Boris Guiu
- Department of Radiology, St. Eloi Hospital, Montpellier University Hospital, 34090 Montpellier, France; (C.C.); (M.H.); (C.A.); (B.G.)
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Finocchiaro D, Gear JI, Fioroni F, Flux GD, Murray I, Castellani G, Versari A, Iori M, Grassi E. Uncertainty analysis of tumour absorbed dose calculations in molecular radiotherapy. EJNMMI Phys 2020; 7:63. [PMID: 33044651 PMCID: PMC7550507 DOI: 10.1186/s40658-020-00328-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 09/16/2020] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Internal dosimetry evaluation consists of a multi-step process ranging from imaging acquisition to absorbed dose calculations. Assessment of uncertainty is complicated and, for that reason, it is commonly ignored in clinical routine. However, it is essential for adequate interpretation of the results. Recently, the EANM published a practical guidance on uncertainty analysis for molecular radiotherapy based on the application of the law of propagation of uncertainty. In this study, we investigated the overall uncertainty on a sample of a patient following the EANM guidelines. The aim of this study was to provide an indication of the typical uncertainties that may be expected from performing dosimetry, to determine parameters that have the greatest effect on the accuracy of calculations and to consider the potential improvements that could be made if these effects were reduced. RESULTS Absorbed doses and the relative uncertainties were calculated for a sample of 49 patients and a total of 154 tumours. A wide range of relative absorbed dose uncertainty values was observed (14-102%). Uncertainties associated with each quantity along the absorbed dose calculation chain (i.e. volume, recovery coefficient, calibration factor, activity, time-activity curve fitting, time-integrated activity and absorbed dose) were estimated. An equation was derived to describe the relationship between the uncertainty in the absorbed dose and the volume. The largest source of error was the VOI delineation. By postulating different values of FWHM, the impact of the imaging system spatial resolution on the uncertainties was investigated. DISCUSSION To the best of our knowledge, this is the first analysis of uncertainty in molecular radiotherapy based on a cohort of clinical cases. Wide inter-lesion variability of absorbed dose uncertainty was observed. Hence, a proper assessment of the uncertainties associated with the calculations should be considered as a basic scientific standard. A model for a quick estimate of uncertainty without implementing the entire error propagation schema, which may be useful in clinical practice, was presented. Ameliorating spatial resolution may be in future the key factor for accurate absorbed dose assessment.
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Affiliation(s)
- Domenico Finocchiaro
- Medical Physics Unit, Azienda Unità Sanitaria Locale di Reggio Emilia - IRCCS, Reggio Emilia, Italy.,Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Jonathan I Gear
- The Royal Marsden NHS Foundation Trust & Institute of Cancer Research, Downs Road, Sutton, SM2 5PT, UK
| | - Federica Fioroni
- Medical Physics Unit, Azienda Unità Sanitaria Locale di Reggio Emilia - IRCCS, Reggio Emilia, Italy.
| | - Glenn D Flux
- The Royal Marsden NHS Foundation Trust & Institute of Cancer Research, Downs Road, Sutton, SM2 5PT, UK
| | - Iain Murray
- The Royal Marsden NHS Foundation Trust & Institute of Cancer Research, Downs Road, Sutton, SM2 5PT, UK
| | - Gastone Castellani
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Annibale Versari
- Nuclear Medicine Unit, Azienda Unità Sanitaria Locale di Reggio Emilia - IRCCS, Reggio Emilia, Italy
| | - Mauro Iori
- Medical Physics Unit, Azienda Unità Sanitaria Locale di Reggio Emilia - IRCCS, Reggio Emilia, Italy
| | - Elisa Grassi
- Medical Physics Unit, Azienda Unità Sanitaria Locale di Reggio Emilia - IRCCS, Reggio Emilia, Italy
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Sudo H, Tsuji AB, Sugyo A, Kurosawa G, Kurosawa Y, Alexander D, Tsuda H, Saga T, Higashi T. Radiolabeled Human Monoclonal Antibody 067-213 has the Potential for Noninvasive Quantification of CD73 Expression. Int J Mol Sci 2020; 21:E2304. [PMID: 32225110 PMCID: PMC7177856 DOI: 10.3390/ijms21072304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/19/2020] [Accepted: 03/19/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND CD73 is an ectonucleotidase regulating extracellular adenosine concentration and plays an important role in adenosine-mediated immunosuppressive pathways. The efficacy of CD73-targeted therapy depends on the expression levels of CD73; therefore, monitoring CD73 status in cancer patients would provide helpful information for selection of patients who would benefit from CD73-targeted therapy. Here, we evaluated the ability of 111In-labeled antibody 067-213, which has high affinity for human CD73, to act as a noninvasive imaging probe. METHODS Cell binding and competitive inhibition assays for 111In-labeled 067-213 were conducted using MIAPaCa-2 (high CD73 expression) and A431 (low CD73 expression) cells. For in vivo assessments, biodistribution and SPECT/CT studies were conducted in MIAPaCa-2 and A431 tumor-bearing mice. To estimate the absorbed dose in humans, biodistribution and SPECT/CT studies were conducted in healthy rats. RESULTS 111In-labeled 067-213 bound to MIAPaCa-2 and A431 cells in a CD73-dependent manner and the affinity loss after 111In-labeling was limited. Biodistribution and SPECT/CT studies with 111In-labeled 067-213 in mice showed high uptake in MIAPaCa-2 tumors and lower uptake in A431 tumors. In rats, the probe did not show high uptake in normal organs, including endogenously CD73-expressing organs. The estimated absorbed doses in humans were reasonably low. CONCLUSIONS 111In-labeled 067-213 showed CD73-expression-dependent tumor uptake and low uptake in normal organs and tissues. Radiolabeled 067-213 holds promise as an imaging probe for noninvasive evaluation of CD73 expression levels in patients. Our data encourage further clinical studies to clarify a role for CD73 monitoring in patients receiving CD73-targeted immune therapy.
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Affiliation(s)
- Hitomi Sudo
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology (QST-NIRS), Inage, Chiba 263-8555, Japan; (H.S.); (A.S.)
| | - Atsushi B. Tsuji
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology (QST-NIRS), Inage, Chiba 263-8555, Japan; (H.S.); (A.S.)
| | - Aya Sugyo
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology (QST-NIRS), Inage, Chiba 263-8555, Japan; (H.S.); (A.S.)
| | - Gene Kurosawa
- International Center for Cell and Gene Therapy, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan;
| | - Yoshikazu Kurosawa
- Department of Innovation Center for Advanced Medicine, Research Promotion Support Center, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan;
| | - David Alexander
- Nanotoxicology Project, Nagoya City University, 3-1 Tanabe-dohri, Mizuho-ku, Nagoya 466-8603, Japan; (D.A.); (H.T.)
| | - Hiroyuki Tsuda
- Nanotoxicology Project, Nagoya City University, 3-1 Tanabe-dohri, Mizuho-ku, Nagoya 466-8603, Japan; (D.A.); (H.T.)
| | - Tsuneo Saga
- Department of Advanced Medical Imaging Research, Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan;
| | - Tatsuya Higashi
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology (QST-NIRS), Inage, Chiba 263-8555, Japan; (H.S.); (A.S.)
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Ismail FS, Mansor S. Impact of Resolution Recovery in Quantitative 99mTc SPECT/CT Cardiac Phantom Studies. J Med Imaging Radiat Sci 2019; 50:449-453. [PMID: 31320272 DOI: 10.1016/j.jmir.2019.05.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 04/08/2019] [Accepted: 05/27/2019] [Indexed: 11/18/2022]
Abstract
BACKGROUND The aim of this study was to validate the quantitative accuracy of single photon emission computed tomography with computed tomography (SPECT/CT) images in cardiac phantom studies. The study was performed by assessing the effect of resolution recovery (RR) when using half-time of imaging acquisition in cardiac phantom. METHODS The SPECT/CT images of the anthropomorphic phantom with a cardiac insert, liver, lung, and spine were acquired using the GE Discovery (NM/CT 670) SPECT/CT system. Different concentration activity ratios for different organ (10:10:1:0, cardiac:liver:background:lung) regions were acquired by using full- and half-time protocols for 643 and 1283 voxel sizes that were reconstructed using filtered back projection (FBP) method and 3D ordered subset expectation maximization (3D-OSEM). Attenuation correction and scatter correction were applied to both reconstructions, whereas the RR only can be applied for 3D-OSEM. The data were analyzed and reported in terms of absolute recovery coefficient percentage between the cardiac insert and background activity concentration. Another parameter used to assess the quantitative accuracy for defect region was the relative error percentage. RESULTS The result of recovery coefficient percentage shows that the 3D-OSEM reconstruction with the RR gives the highest percentage estimation accuracy of 70% of activity recovery in the cardiac phantom wall compared with FBP (10.6%). The relative error percentage for reconstructed SPECT/CT images using 3D-OSEM reconstruction with RR shows the least error compared with FBP (21% vs. 45.1%) both in the full-and half-time acquisition of images with a larger number of matrix size used. CONCLUSIONS 3D-OSEM reconstruction with the RR is beneficial in giving better quantitative evaluation with a good resolution myocardial perfusion image. To accomplish this, a larger matrix size is required for 3D-OSEM reconstruction with the RR and it demonstrated an improvement in image resolution and increased quantitative accuracy of the final reconstructed SPECT/CT images.
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Affiliation(s)
- Faizatul Shahira Ismail
- Oncological and Radiological Science Cluster, Advanced Medical and Dental Institute SAINS@BERTAM, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia
| | - Syahir Mansor
- Oncological and Radiological Science Cluster, Advanced Medical and Dental Institute SAINS@BERTAM, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia.
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Grudzinski JJ, Hernandez R, Marsh I, Patel RB, Aluicio-Sarduy E, Engle J, Morris Z, Bednarz B, Weichert J. Preclinical Characterization of 86/90Y-NM600 in a Variety of Murine and Human Cancer Tumor Models. J Nucl Med 2019; 60:1622-1628. [PMID: 30954941 DOI: 10.2967/jnumed.118.224808] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/26/2019] [Indexed: 11/16/2022] Open
Abstract
We characterize the in vivo biodistribution and tumor selectivity of 86Y-NM600, a theranostic alkylphosphocholine radiometal chelate with broad tumor selectivity, in a variety of preclinical cancer models. Methods: Mice bearing flank tumors (representative of lung, pancreatic, prostate, liver, skin, and lymphoid cancers) were injected intravenously with 9.25 MBq of 86Y-NM600 and imaged longitudinally over 4-5 d using small-animal PET/CT. Percentage injected activity per gram (%IA/g) for each volume of interest was measured at each time point for the organs of interest. Mice were euthanized after the final time point, and the tumor and organs of interest were counted with an automatic γ-counter. Absorbed doses delivered by 90Y-NM600 per injected activity (Gy/MBq) were estimated. Mice bearing B78 flank tumors were injected with a prescription of 90Y-NM600 that delivered 2.5 Gy of absorbed tumor dose and was compared with an equivalent absorbed dose delivered via external-beam radiotherapy using tumor volume as a measure of response. Histology and complete blood counts were analyzed in naïve C57BL/6 mice that were injected with 9.25 MBq of 90Y-NM600 at 5, 10, and 28 d after injection. Results: PET imaging showed consistent tumor accumulation and retention across all tumor models investigated, with little off-target retention of NM600 except in the liver, as is characteristic of hepatobiliary metabolism. The tumor uptake was highest in the pancreatic and lymphoid cancer models, reaching peak concentrations of 9.34 ± 2.66 %IA/g (n = 3) and 9.10 ± 0.13 %IA/g (n = 3), respectively, at approximately 40-48 h after injection. These corresponded to tumor dose estimates of 2.72 ± 0.33 Gy/MBq and 2.67 ± 0.32 Gy/MBq, respectively. In the toxicity study, there were no visible signs of acute toxicity by histology, and perturbation of hematologic parameters was transient when observed, returning to pretherapy levels after 28 d. Conclusion: NM600 is a theranostic agent with a unique ability to selectively target a variety of cancer types, presenting a unique opportunity for PET image-guided targeted radionuclide therapy and combination with immunotherapies.
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Affiliation(s)
- Joseph J Grudzinski
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Reinier Hernandez
- Department of Radiology, University of Wisconsin, Madison, Wisconsin
| | - Ian Marsh
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Ravi B Patel
- Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin; and
| | | | - Jon Engle
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Radiology, University of Wisconsin, Madison, Wisconsin
| | - Zachary Morris
- Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Bryan Bednarz
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Radiology, University of Wisconsin, Madison, Wisconsin.,Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Jamey Weichert
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Radiology, University of Wisconsin, Madison, Wisconsin.,University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
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Medical nuclomics. Nucl Med Commun 2019; 40:294-296. [DOI: 10.1097/mnm.0000000000000975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Santoro L, Mora-Ramirez E, Trauchessec D, Chouaf S, Eustache P, Pouget JP, Kotzki PO, Bardiès M, Deshayes E. Implementation of patient dosimetry in the clinical practice after targeted radiotherapy using [ 177Lu-[DOTA0, Tyr3]-octreotate. EJNMMI Res 2018; 8:103. [PMID: 30498938 PMCID: PMC6265360 DOI: 10.1186/s13550-018-0459-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 11/20/2018] [Indexed: 01/01/2023] Open
Abstract
Background This study’s aim was to develop our dosimetric methodology using a commercial workstation for the routine evaluation of the organs at risk during peptide receptor radionuclide therapy (PRRT) with 177Lu. Methods First, planar and SPECT sensitivity factors were determined on phantoms. The reconstruction parameters were optimized by SPECT/CT image acquisition using a NEMA IEC phantom containing a 500 ml bottle of 177Lu, to simulate a kidney. The recovery coefficients were determined on various phantoms. For the red marrow, this was calculated using a NEMA IEC phantom that contained a centrally placed bottle of 80 ml of 177Lu (to model the L2-L4 red marrow) flanked by two 200 ml bottles with 177Lu to simulate the kidneys. Then, SPECT/CT images were acquired at 4, 24, 72, and 192 h after injection in 12 patients with neuroendocrine tumors who underwent PRRT with 177Lu-DOTATATE. SPECT data were reconstructed using the iterative ordered subset expectation maximization (OSEM) method, with six iterations and ten subsets, attenuation, scatter, recovery resolution corrections, and a Gaussian post-filter of 0.11 cm. The liver, spleen, kidneys, and red marrow dose per administered activity (AD/A admin) values were calculated with the Medical Internal Radiation Dose (MIRD) formalism and the residence times (Dosimetry toolkit® application) using standard and CT imaging-based organ masses (OLINDA/EXM® V1.0 software). Results Sensitivity factors of 6.11 ± 0.01 and 5.67 ± 0.08 counts/s/MBq were obtained with planar and SPECT/CT acquisitions, respectively. A recovery coefficient of 0.78 was obtained for the modeled L2–L4 red marrow. The mean AD/A admin values were 0.43 ± 0.13 mGy/MBq [0.27–0.91] for kidneys, 0.54 ± 0.58 mGy/MBq [0.12–2.26] for liver, 0.61 ± 0.13 mGy/MBq [0.42–0.89] for spleen, and 0.04 ± 0.02 mGy/MBq [0.01–0.09] for red marrow. The AD/A admin values varied when calculated using the personalized and standard organ mass, particularly for kidneys (p = 1 × 10−7), spleen (p = 0.0069), and red marrow (p = 0.0027). Intra-patient differences were observed especially in organs close to or including tumor cells or metastases. Conclusions The obtained AD/A admin values were in agreement with the literature data. This study shows the technical feasibility of patient dosimetry in clinical practice and the need to obtain patient-specific information.
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Affiliation(s)
- Lore Santoro
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France.
| | - Erick Mora-Ramirez
- Centre de Recherche en Cancérologie de Toulouse, Toulouse, France.,INSERM, UMR 1037, Toulouse III Paul Sabatier University, Toulouse, France.,University of Costa Rica, Physics School, CICANUM, San Jose, Costa Rica
| | - Dorian Trauchessec
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France
| | - Soufiane Chouaf
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France
| | - Pierre Eustache
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France
| | - Jean-Pierre Pouget
- Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Université de Montpellier, Institut Régional du Cancer de Montpellier (ICM), Montpellier, France
| | - Pierre-Olivier Kotzki
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France.,Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Université de Montpellier, Institut Régional du Cancer de Montpellier (ICM), Montpellier, France
| | - Manuel Bardiès
- Centre de Recherche en Cancérologie de Toulouse, Toulouse, France.,INSERM, UMR 1037, Toulouse III Paul Sabatier University, Toulouse, France
| | - Emmanuel Deshayes
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298, Montpellier Cedex5, France.,Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Université de Montpellier, Institut Régional du Cancer de Montpellier (ICM), Montpellier, France
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Bastiaannet R, Kappadath SC, Kunnen B, Braat AJAT, Lam MGEH, de Jong HWAM. The physics of radioembolization. EJNMMI Phys 2018; 5:22. [PMID: 30386924 PMCID: PMC6212377 DOI: 10.1186/s40658-018-0221-z] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 06/19/2018] [Indexed: 12/11/2022] Open
Abstract
Radioembolization is an established treatment for chemoresistant and unresectable liver cancers. Currently, treatment planning is often based on semi-empirical methods, which yield acceptable toxicity profiles and have enabled the large-scale application in a palliative setting. However, recently, five large randomized controlled trials using resin microspheres failed to demonstrate a significant improvement in either progression-free survival or overall survival in both hepatocellular carcinoma and metastatic colorectal cancer. One reason for this might be that the activity prescription methods used in these studies are suboptimal for many patients.In this review, the current dosimetric methods and their caveats are evaluated. Furthermore, the current state-of-the-art of image-guided dosimetry and advanced radiobiological modeling is reviewed from a physics' perspective. The current literature is explored for the observation of robust dose-response relationships followed by an overview of recent advancements in quantitative image reconstruction in relation to image-guided dosimetry.This review is concluded with a discussion on areas where further research is necessary in order to arrive at a personalized treatment method that provides optimal tumor control and is clinically feasible.
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Affiliation(s)
- Remco Bastiaannet
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E01.132, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
| | - S. Cheenu Kappadath
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, 1155 Pressler St, Unit 1352, Houston, TX 77030 USA
| | - Britt Kunnen
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E01.132, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
| | - Arthur J. A. T. Braat
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E01.132, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
| | - Marnix G. E. H. Lam
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E01.132, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
| | - Hugo W. A. M. de Jong
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Room E01.132, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
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Halty A, Badel JN, Kochebina O, Sarrut D. Image-based SPECT calibration based on the evaluation of the Fraction of Activity in the Field of View. EJNMMI Phys 2018; 5:11. [PMID: 29766354 PMCID: PMC5953912 DOI: 10.1186/s40658-018-0209-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 03/16/2018] [Indexed: 11/27/2022] Open
Abstract
Background SPECT quantification is important for dosimetry in targeted radionuclide therapy (TRT) and the calibration of SPECT images is a crucial stage for image quantification. The current standardized calibration protocol (MIRD 23) uses phantom acquisitions to derive a global calibration factor in specific conditions. It thus requires specific acquisitions for every clinical protocols. We proposed an alternative and complementary image-based calibration method that allows to determine a calibration factor adapted to each patient, radionuclide, and acquisition protocol and that may also be used as an additional independent calibration. Results The proposed method relies on a SPECT/CT acquisition of a given region of interest and an initial whole-body (WB) planar image. First, the conjugate view of WB planar images is computed after scatter and attenuation correction. 3D SPECT images are reconstructed with scatter, attenuation, and collimator-detector response (CDR) corrections and corrected from apparent dead-time. The field of view (FOV) of the SPECT image is then projected on the corrected WB planar image. The fraction of activity located in the area corresponding to the SPECT FOV is then calculated based on the counts on the corrected WB planar image. The Fraction of Activity in Field Of View (FAF) is then proposed to compute the calibration factor as the total number of counts in the SPECT image divided by this activity. Quantification accuracy was compared with the standard calibration method both with phantom experiments and on patient data. Both standard and image-based calibrations give good accuracy on large region of interest on phantom experiments (less than 7% of relative difference compared to ground truth). Apparent dead-time correction allows to reduce the uncertainty associated with standard calibration from 2.5 to 1%. The differences found between both methods were lower than the uncertainty range of the standard calibration (<3%). In patient data, although no ground truth was available, both methods give similar calibration factor (average difference 3.64%). Conclusions A calibration factor may be computed directly from the acquired SPECT image providing that a WB planar image is also available and if both acquisitions are performed before biological elimination. This method does not require to perform phantom acquisition for every different acquisition conditions and may serve to double check the calibration with an independent factor.
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Affiliation(s)
- Adrien Halty
- Univ Lyon, INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, 69008, France. .,Univ Lyon, Centre Léon Bérard, Lyon, 69008, France.
| | | | - Olga Kochebina
- Univ Lyon, INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, 69008, France
| | - David Sarrut
- Univ Lyon, INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, 69008, France.,Univ Lyon, Centre Léon Bérard, Lyon, 69008, France
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Determination of gamma camera calibration factors for quantitation of therapeutic radioisotopes. EJNMMI Phys 2018; 5:8. [PMID: 29717385 PMCID: PMC5930296 DOI: 10.1186/s40658-018-0208-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/23/2018] [Indexed: 01/23/2023] Open
Abstract
Background Camera calibration, which translates reconstructed count map into absolute activity map, is a prerequisite procedure for quantitative SPECT imaging. Both planar and tomographic scans using different phantom geometries have been proposed for the determination of the camera calibration factor (CF). However, there is no consensus on which approach is the best. The aim of this study is to evaluate all these calibration methods, compare their performance, and propose a practical and accurate calibration method for SPECT quantitation of therapeutic radioisotopes. Twenty-one phantom experiments (Siemens Symbia SPECT/CT) and 12 Monte Carlo simulations (GATE v6.1) using three therapy isotopes (131I, 177Lu, and 188Re) have been performed. The following phantom geometries were used: (1) planar scans of point source in air (PS), (2) tomographic scans of insert(s) filled with activity placed in non-radioactive water (HS + CB), (3) tomographic scans of hot insert(s) in radioactive water (HS + WB), and (4) tomographic scans of cylinders uniformly filled with activity (HC). Tomographic data were reconstructed using OSEM with CT-based attenuation correction and triple energy window (TEW) scatter correction, and CF was determined using total counts in the reconstructed image, while for planar scans, the photopeak counts, corrected for scatter and background with TEW, were used. Additionally, for simulated data, CF obtained from primary photons only was analyzed. Results For phantom experiments, CF obtained from PS and HS + WB agreed to within 6% (below 3% if experiments performed on the same day are considered). However, CF from HS + CB exceeded those from PS by 4–12%. Similar trend was found in simulation studies. Analysis of CFs from primary photons helped us to understand this discrepancy. It was due to underestimation of scatter by the TEW method, further enhanced by attenuation correction. This effect becomes less important when the source is distributed over the entire phantom volume (HS + WB and HC). Conclusions Camera CF could be determined using planar scans of a point source, provided that the scatter and background contributions are removed, for example using the clinically available TEW method. This approach is simple and yet provides CF with sufficient accuracy (~ 5%) to be used in clinics for radiotracer quantification.
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Abstract
Transporter systems involved in the permeation of drugs and solutes across biological membranes are recognized as key determinants of pharmacokinetics. Typically, the action of membrane transporters on drug exposure to tissues in living organisms is inferred from invasive procedures, which cannot be applied in humans. In recent years, imaging methods have greatly progressed in terms of instruments, synthesis of novel imaging probes as well as tools for data analysis. Imaging allows pharmacokinetic parameters in different tissues and organs to be obtained in a non-invasive or minimally invasive way. The aim of this overview is to summarize the current status in the field of molecular imaging of drug transporters. The overview is focused on human studies, both for the characterization of transport systems for imaging agents as well as for the determination of drug pharmacokinetics, and makes reference to animal studies where necessary. We conclude that despite certain methodological limitations, imaging has a great potential to study transporters at work in humans and that imaging will become an important tool, not only in drug development but also in medicine. Imaging allows the mechanistic aspects of transport proteins to be studied, as well as elucidating the influence of genetic background, pathophysiological states and drug-drug interactions on the function of transporters involved in the disposition of drugs.
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Affiliation(s)
- Nicolas Tournier
- Imagerie Moléculaire In Vivo, IMIV, CEA, Inserm, CNRS, Univ. Paris-Sud, Université Paris Saclay, CEA-SHFJ, Orsay, France
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Oliver Langer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria; Biomedical Systems, Center for Health & Bioresources, AIT Austrian Institute of Technology GmbH, Seibersdorf, Austria; Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.
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Dual time-point quantitative SPECT-CT parathyroid imaging using a single computed tomography. Nucl Med Commun 2018; 39:3-9. [DOI: 10.1097/mnm.0000000000000761] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Uribe CF, Esquinas PL, Tanguay J, Gonzalez M, Gaudin E, Beauregard JM, Celler A. Accuracy of 177Lu activity quantification in SPECT imaging: a phantom study. EJNMMI Phys 2017; 4:2. [PMID: 28063068 PMCID: PMC5218957 DOI: 10.1186/s40658-016-0170-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 12/20/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The aim of the study is to assess accuracy of activity quantification of 177Lu studies performed according to recommendations provided by the committee on Medical Internal Radiation Dose (MIRD) pamphlets 23 and 26. The performances of two scatter correction and three segmentation methods were compared. Additionally, the accuracy of tomographic and planar methods for determination of the camera normalization factor (CNF) was evaluated. Eight phantoms containing inserts of different sizes and shapes placed in air, water, and radioactive background were scanned using a Siemens SymbiaT SPECT/CT camera. Planar and tomographic scans with 177Lu sources were used to measure CNF. Images were reconstructed with our SPEQToR software using resolution recovery, attenuation, and two scatter correction methods (analytical photon distribution interpolated (APDI) and triple energy window (TEW)). Segmentation was performed using a fixed threshold method for both air and cold water scans. For hot water experiments three segmentation methods were compared as folows: a 40% fixed threshold, segmentation based on CT images, and our iterative adaptive dual thresholding (IADT). Quantification error, defined as the percent difference between experimental and true activities, was evaluated. RESULTS Quantification error for scans in air was better for TEW scatter correction (<6%) than for APDI (<11%). This trend was reversed for scans in water (<10% for APDI and <14% for TEW). For hot water, the best results (<18% for small objects and <5% for objects >100 ml) were obtained when APDI and IADT were used for scatter correction and segmentation, respectively. Additionally, we showed that planar acquisitions with scatter correction and tomographic scans provide similar CNF values. This is an important finding because planar acquisitions are easier to perform than tomographic scans. TEW and APDI resulted in similar quantification errors with APDI showing a small advantage for objects placed in medium with non-uniform density. CONCLUSIONS Following the MIRD recommendations for data acquisition and reconstruction resulted in accurate activity quantification (errors <5% for large objects). However, techniques for better organ/tumor segmentation must still be developed.
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Affiliation(s)
- Carlos F Uribe
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, Vancouver, British Colombia, Canada.
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Colombia, Canada.
- Department of Molecular Oncology, BC Cancer Research Centre, Vancouver, British Colombia, Canada.
| | - Pedro L Esquinas
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, Vancouver, British Colombia, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Colombia, Canada
| | - Jesse Tanguay
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, Vancouver, British Colombia, Canada
| | - Marjorie Gonzalez
- Vancouver Coastal Health Authority, Vancouver, British Colombia, Canada
| | - Emilie Gaudin
- Department of Physics, Engineering Physics and Optics, Université Laval, Quebec City, Quebec, Canada
| | - Jean-Mathieu Beauregard
- Department of Medical Imaging, CHU de Quebec-Université Laval, Quebec City, Quebec, Canada
- Department of Radiology and Nuclear Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Anna Celler
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, Vancouver, British Colombia, Canada
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Uncertainty Analysis in the Calibration of an Emission Tomography System for Quantitative Imaging. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2017; 2017:9830386. [PMID: 29312467 PMCID: PMC5660760 DOI: 10.1155/2017/9830386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 08/15/2017] [Indexed: 11/25/2022]
Abstract
It is generally acknowledged that calibration of the imaging system (be it a SPECT or a PET scanner) is one of the critical components associated with in vivo activity quantification in nuclear medicine. The system calibration is generally performed through the acquisition of a source with a known amount of radioactivity. The decay-corrected calibration factor is the “output” quantity in a measurement model for the process. This quantity is a function of a number of “input” variables, including total counts in the volume of interest (VOI), radionuclide activity concentration, source volume, acquisition duration, radionuclide half-life, and calibration time of the radionuclide. Uncertainties in the input variables propagate through the calculation to the “combined” uncertainty in the output quantity. In the present study, using the general formula given in the GUM (Guide to the Expression of Uncertainty in Measurement) for aggregating uncertainty components, we derive a practical relation to assess the combined standard uncertainty for the calibration factor of an emission tomography system. At a time of increasing need for accuracy in quantification studies, the proposed approach has the potential to be easily implemented in clinical practice.
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Pacilio M, Ferrari M, Chiesa C, Lorenzon L, Mira M, Botta F, Becci D, Torres LA, Coca Perez M, Vergara Gil A, Basile C, Ljungberg M, Pani R, Cremonesi M. Impact of SPECT corrections on 3D-dosimetry for liver transarterial radioembolization using the patient relative calibration methodology. Med Phys 2017; 43:4053. [PMID: 27370124 DOI: 10.1118/1.4953203] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
PURPOSE Many centers aim to plan liver transarterial radioembolization (TARE) with dosimetry, even without CT-based attenuation correction (AC), or with unoptimized scatter correction (SC) methods. This work investigates the impact of presence vs absence of such corrections, and limited spatial resolution, on 3D dosimetry for TARE. METHODS Three voxelized phantoms were derived from CT images of real patients with different body sizes. Simulations of (99m)Tc-SPECT projections were performed with the SIMIND code, assuming three activity distributions in the liver: uniform, inside a "liver's segment," or distributing multiple uptaking nodules ("nonuniform liver"), with a tumoral liver/healthy parenchyma ratio of 5:1. Projection data were reconstructed by a commercial workstation, with OSEM protocol not specifically optimized for dosimetry (spatial resolution of 12.6 mm), with/without SC (optimized, or with parameters predefined by the manufacturer; dual energy window), and with/without AC. Activity in voxels was calculated by a relative calibration, assuming identical microspheres and (99m)Tc-SPECT counts spatial distribution. 3D dose distributions were calculated by convolution with (90)Y voxel S-values, assuming permanent trapping of microspheres. Cumulative dose-volume histograms in lesions and healthy parenchyma from different reconstructions were compared with those obtained from the reference biodistribution (the "gold standard," GS), assessing differences for D95%, D70%, and D50% (i.e., minimum value of the absorbed dose to a percentage of the irradiated volume). γ tool analysis with tolerance of 3%/13 mm was used to evaluate the agreement between GS and simulated cases. The influence of deep-breathing was studied, blurring the reference biodistributions with a 3D anisotropic gaussian kernel, and performing the simulations once again. RESULTS Differences of the dosimetric indicators were noticeable in some cases, always negative for lesions and distributed around zero for parenchyma. Application of AC and SC reduced systematically the differences for lesions by 5%-14% for a liver segment, and by 7%-12% for a nonuniform liver. For parenchyma, the data trend was less clear, but the overall range of variability passed from -10%/40% for a liver segment, and -10%/20% for a nonuniform liver, to -13%/6% in both cases. Applying AC, SC with preset parameters gave similar results to optimized SC, as confirmed by γ tool analysis. Moreover, γ analysis confirmed that solely AC and SC are not sufficient to obtain accurate 3D dose distribution. With breathing, the accuracy worsened severely for all dosimetric indicators, above all for lesions: with AC and optimized SC, -38%/-13% in liver's segment, -61%/-40% in the nonuniform liver. For parenchyma, D50% resulted always less sensitive to breathing and sub-optimal correction methods (difference overall range: -7%/13%). CONCLUSIONS Reconstruction protocol optimization, AC, SC, PVE and respiratory motion corrections should be implemented to obtain the best possible dosimetric accuracy. On the other side, thanks to the relative calibration, D50% inaccuracy for the healthy parenchyma from absence of AC was less than expected, while the optimization of SC was scarcely influent. The relative calibration therefore allows to perform TARE planning, basing on D50% for the healthy parenchyma, even without AC or with suboptimal corrections, rather than rely on nondosimetric methods.
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Affiliation(s)
- Massimiliano Pacilio
- Department of Medical Physics, Azienda Ospedaliera San Camillo Forlanini, Rome 00152, Italy
| | - Mahila Ferrari
- Department of Medical Physics, Istituto Europeo di Oncologia, Milan 20141, Italy
| | - Carlo Chiesa
- Department of Nuclear Medicine, Istituto Nazionale Tumori IRCCS Foundation, Milan 20133, Italy
| | - Leda Lorenzon
- Postgraduate School of Medical Physics, "Sapienza" University of Rome, Rome 00185, Italy
| | - Marta Mira
- Post graduate Health Physics School, University of Milan, Milan 20122, Italy
| | - Francesca Botta
- Department of Medical Physics, Istituto Europeo di Oncologia, Milan 20141, Italy
| | - Domenico Becci
- Postgraduate School of Medical Physics, "Sapienza" University of Rome, Rome 00185, Italy
| | - Leonel Alberto Torres
- Department of Nuclear Medicine, Clinical Research Division of the Center of Isotopes (DIC-CENTIS), Havana 11100, Cuba
| | - Marco Coca Perez
- Department of PET-CT and Nuclear Medicine, Imaging Center Medscan-Concepciòn, Concepciòn 4070061, Chile
| | - Alex Vergara Gil
- Department of Nuclear Medicine, Clinical Research Division of the Center of Isotopes (DIC-CENTIS), Havana 11100, Cuba
| | - Chiara Basile
- Department of Medical Physics, Azienda Ospedaliera San Camillo Forlanini, Rome 00152, Italy
| | - Michael Ljungberg
- Department of Medical Radiation Physics, University of Lund, Lund 22100, Sweden
| | - Roberto Pani
- Department of Medico-surgical Sciences and Biotecnologies, "Sapienza" University of Rome, Rome 00185, Italy
| | - Marta Cremonesi
- Department of Medical Physics, Istituto Europeo di Oncologia, Milan 20141, Italy
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Geometrical parameters and scattered radiation effects on the extrinsic sensitivity and counting efficiency of a rectangular gamma camera. Appl Radiat Isot 2016; 118:131-135. [PMID: 27640173 DOI: 10.1016/j.apradiso.2016.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 09/06/2016] [Accepted: 09/06/2016] [Indexed: 11/21/2022]
Abstract
A point source is used to investigate the effect of water phantom thickness and source-to-detector distance (SDD) on the sensitivity and counting efficiency of a rectangular detector gamma camera. The increase in water thickness resulted in an increase in scatter fraction, a decrease in sensitivity, and counting efficiency. The increase in SDD resulted in a decrease in sensitivity and an increase in counting efficiency. An SDD of 0.79±0.02m is found to provide a good compromise for acceptable sensitivity and reasonable counting efficiency.
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McDougald WA, Miyaoka RS, Alessio AM, Harrison RL, Lewellen TK. A study of SPECT/CT camera stability for quantitative imaging. EJNMMI Phys 2016; 3:14. [PMID: 27473290 PMCID: PMC4967048 DOI: 10.1186/s40658-016-0150-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 06/28/2016] [Indexed: 12/02/2022] Open
Abstract
Background The purpose of this study was twofold: to evaluate the quantitative stability of a SPECT/CT gamma camera over time and to determine if daily flood acquisitions can reliably serve as calibration factors for quantitative SPECT. Using a cylindrical water phantom filled with measured amounts of 99mTc, factors were calculated to convert counts/cc to activity/cps. Measurements were made over an 18-month period. System sensitivity data calculated from 57Co daily quality assurance (DQA) flood acquisitions were then compared to the 99mTc calibration factors to determine the relationship of the factors. Results The coefficient of variation is 2.7 % for the 99mTc cylinder conversion factors and 2.6 % for the 57Co DQA flood data. The greatest difference between the cylinder conversion factors and the flood data is less than 3 %. Conclusions Based on the results, the camera was stable within 3 % over an 18-month time period. The daily flood source acquisitions can be a reliable source for tracking camera stability and may provide information on updating the calibration factor for quantitative imaging.
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Affiliation(s)
- Wendy A McDougald
- Imaging Research Laboratory, Department of Radiology, University of Washington, 222 Portage Bay Building, Box 357987, Seattle, WA, 98195-7987, USA.
| | - Robert S Miyaoka
- Imaging Research Laboratory, Department of Radiology, University of Washington, 222 Portage Bay Building, Box 357987, Seattle, WA, 98195-7987, USA
| | - Adam M Alessio
- Imaging Research Laboratory, Department of Radiology, University of Washington, 222 Portage Bay Building, Box 357987, Seattle, WA, 98195-7987, USA
| | - Robert L Harrison
- Imaging Research Laboratory, Department of Radiology, University of Washington, 222 Portage Bay Building, Box 357987, Seattle, WA, 98195-7987, USA
| | - Thomas K Lewellen
- Imaging Research Laboratory, Department of Radiology, University of Washington, 222 Portage Bay Building, Box 357987, Seattle, WA, 98195-7987, USA
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Gamma camera calibration and validation for quantitative SPECT imaging with 177Lu. Appl Radiat Isot 2016; 112:156-64. [DOI: 10.1016/j.apradiso.2016.03.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/09/2016] [Accepted: 03/07/2016] [Indexed: 11/21/2022]
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Pak K, Kim SJ. What Do We Measure in Oncology PET? Nucl Med Mol Imaging 2016; 51:212-216. [PMID: 28878846 DOI: 10.1007/s13139-016-0416-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 03/08/2016] [Accepted: 04/01/2016] [Indexed: 12/13/2022] Open
Abstract
Positron emission tomography (PET) has come to the practice of oncology. It is known that 18F-fluorodeoxyglucose (FDG) PET is more sensitive for the assessment of treatment response than conventional imaging. In addition, PET has an advantage in the use of quantitative analysis of the study. Nowadays, various PET parameters are adopted in clinical settings. In addition, a wide range of factors has been known to be associated with FDG uptake. Therefore, there has been a need for standardization and harmonization of protocols and PET parameters. We will introduce PET parameters and discuss major issues in this review.
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Affiliation(s)
- Kyoungjune Pak
- Department of Nuclear Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan, Korea
| | - Seong-Jang Kim
- Department of Nuclear Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.,Department of Nuclear Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Pusan National University, Yangsan, Korea
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Sullivan DC, Obuchowski NA, Kessler LG, Raunig DL, Gatsonis C, Huang EP, Kondratovich M, McShane LM, Reeves AP, Barboriak DP, Guimaraes AR, Wahl RL. Metrology Standards for Quantitative Imaging Biomarkers. Radiology 2015; 277:813-25. [PMID: 26267831 PMCID: PMC4666097 DOI: 10.1148/radiol.2015142202] [Citation(s) in RCA: 289] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Although investigators in the imaging community have been active in developing and evaluating quantitative imaging biomarkers (QIBs), the development and implementation of QIBs have been hampered by the inconsistent or incorrect use of terminology or methods for technical performance and statistical concepts. Technical performance is an assessment of how a test performs in reference objects or subjects under controlled conditions. In this article, some of the relevant statistical concepts are reviewed, methods that can be used for evaluating and comparing QIBs are described, and some of the technical performance issues related to imaging biomarkers are discussed. More consistent and correct use of terminology and study design principles will improve clinical research, advance regulatory science, and foster better care for patients who undergo imaging studies.
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Affiliation(s)
- Daniel C. Sullivan
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Nancy A. Obuchowski
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Larry G. Kessler
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - David L. Raunig
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Constantine Gatsonis
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Erich P. Huang
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Marina Kondratovich
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Lisa M. McShane
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Anthony P. Reeves
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Daniel P. Barboriak
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Alexander R. Guimaraes
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
| | - Richard L. Wahl
- From the Department of Radiology, Duke University Medical Center, Box 2715, Durham, NC 27710 (D.C.S., D.P.B.); Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (N.A.O.); Department of Public Health, University of Washington, Seattle, Wash (L.G.K.); Department of Informatics, ICON Medical, Washington, Pa (D.L.R.); Center for Statistical Sciences, Brown University, Providence, RI (C.G.); National Cancer Institute, Bethesda, Md (E.P.H., L.M.M.); Center for Devices and Radiological Health, U.S. Food and Drug Administration, White Oak, Md (M.K.); Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY (A.P.R.); Department of Radiology, Oregon Health & Science University, Portland, Ore (A.R.G.); and Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (R.L.W.)
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Vanhove C, Bankstahl JP, Krämer SD, Visser E, Belcari N, Vandenberghe S. Accurate molecular imaging of small animals taking into account animal models, handling, anaesthesia, quality control and imaging system performance. EJNMMI Phys 2015; 2:31. [PMID: 26560138 PMCID: PMC4642455 DOI: 10.1186/s40658-015-0135-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 11/05/2015] [Indexed: 11/22/2022] Open
Abstract
Small-animal imaging has become an important technique for the development of new radiotracers, drugs and therapies. Many laboratories have now a combination of different small-animal imaging systems, which are being used by biologists, pharmacists, medical doctors and physicists. The aim of this paper is to give an overview of the important factors in the design of a small animal, nuclear medicine and imaging experiment. Different experts summarize one specific aspect important for a good design of a small-animal experiment.
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Affiliation(s)
- Christian Vanhove
- Department of Electronics and Information Systems, MEDISIP, Ghent University-iMinds Medical IT-IBiTech, De Pintelaan 185 block B, B-9000, Ghent, Belgium.
| | - Jens P Bankstahl
- Department of Nuclear Medicine, Preclinical Molecular Imaging, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Stefanie D Krämer
- Radiopharmaceutical Sciences/Biopharmacy, ETH Zurich, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| | - Eric Visser
- Department of Radiology and Nuclear Medicine, Radboudumc, 6525 GA Nijmegen, the Netherlands
| | - Nicola Belcari
- Department of Physics, University of Pisa and INFN sezione di Pisa, 56127 Pisa, Italy
| | - Stefaan Vandenberghe
- Department of Electronics and Information Systems, MEDISIP, Ghent University-iMinds Medical IT-IBiTech, De Pintelaan 185 block B, B-9000, Ghent, Belgium
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Anizan N, Wang H, Zhou XC, Hobbs RF, Wahl RL, Frey EC. Factors affecting the stability and repeatability of gamma camera calibration for quantitative imaging applications based on a retrospective review of clinical data. EJNMMI Res 2014; 4:67. [PMID: 26116127 PMCID: PMC4452683 DOI: 10.1186/s13550-014-0067-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 11/21/2014] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Absolute quantitative single-photon emission computed tomography (SPECT) has several important applications including monitoring tumor response after treatment and dose estimation for targeted radionuclide therapy treatment planning. Obtaining quantitative SPECT images in absolute activity units requires the use of a calibration factor, and the repeatability of this directly affects the repeatability of image quantification. This study focused on evaluating the factors affecting the repeatability of a calibration factor measured using a planar image of an in-air calibration source. METHODS The calibration factors calculated as part of (131)I-tositumomab patient dosimetry scans used in treatment planning performed over a 4-year period were retrospectively analyzed. Raw data included total counts in whole-body images of a radioactive calibration source, the activity of the source measured in a radionuclide activity meter (often referred to as a dose calibrator), and the background count rate obtained at three time points for each patient. The count rate from extrinsic flood source acquisitions and radionuclide activity meter constancy obtained on the same day as each image were also used. The data were analyzed statistically using a mixed-effects model to determine the factors affecting variations in the measured calibration factors. RESULTS The global variability in the calibration factor was equal to 2.3% and was decreased by 20% to 1.8%, when the decay-corrected measurements of calibration source activity were averaged over the three time points for each patient. Camera sensitivity variation measured using a (57)Co sheet source was small and had a weak relationship to calibration factor variations. When the averaged source activity was used, the main source of variance was related to preparation and measurement of the source (77%). Radionuclide activity meter constancy had a smaller but statistically significant impact on the calibration factor. CONCLUSIONS This study indicates that calibration factors based on planar measurements have good reproducibility. The findings of this study indicate (1) the importance of accurate and precise preparation and measurement of the calibration source activity, (2) the need to carefully control background activity during calibration factor assessment and patient data acquisition, and (3) that the calibration factor and camera sensitivity were stable over time, indicating that careful but less frequent calibration is needed.
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Affiliation(s)
- Nadège Anizan
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, 601 North Caroline Street/JHOC 4263, Baltimore, Maryland, 21287, USA,
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Roé-Vellvé N, Pino F, Falcon C, Cot A, Gispert JD, Marin C, Pavía J, Ros D. Quantification of rat brain SPECT with (123)I-ioflupane: evaluation of different reconstruction methods and image degradation compensations using Monte Carlo simulation. Phys Med Biol 2014; 59:4567-82. [PMID: 25069105 DOI: 10.1088/0031-9155/59/16/4567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
SPECT studies with (123)I-ioflupane facilitate the diagnosis of Parkinson's disease (PD). The effect on quantification of image degradations has been extensively evaluated in human studies but their impact on studies of experimental PD models is still unclear. The aim of this work was to assess the effect of compensating for the degrading phenomena on the quantification of small animal SPECT studies using (123)I-ioflupane. This assessment enabled us to evaluate the feasibility of quantitatively detecting small pathological changes using different reconstruction methods and levels of compensation for the image degrading phenomena. Monte Carlo simulated studies of a rat phantom were reconstructed and quantified. Compensations for point spread function (PSF), scattering, attenuation and partial volume effect were progressively included in the quantification protocol. A linear relationship was found between calculated and simulated specific uptake ratio (SUR) in all cases. In order to significantly distinguish disease stages, noise-reduction during the reconstruction process was the most relevant factor, followed by PSF compensation. The smallest detectable SUR interval was determined by biological variability rather than by image degradations or coregistration errors. The quantification methods that gave the best results allowed us to distinguish PD stages with SUR values that are as close as 0.5 using groups of six rats to represent each stage.
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Affiliation(s)
- N Roé-Vellvé
- Unitat de Biofísica i Bioenginyeria, Universitat de Barcelona, Casanova 143, 08036 Barcelona, Spain. Unidad de Imagen, CIMES, Fundación General de la Universidad de Málaga, Marqués de Beccaria 3, 29010, Málaga, Spain
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Shcherbinin S, Grimes J, Bator A, Cwikla JB, Celler A. Three-dimensional personalized dosimetry for 188Re liver selective internal radiation therapy based on quantitative post-treatment SPECT studies. Phys Med Biol 2013; 59:119-134. [PMID: 24334821 DOI: 10.1088/0031-9155/59/1/119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We demonstrate that accurate patient-specific distributions of microspheres labeled with 188Re and resulting absorbed doses can be obtained from single-photon emission computed tomography (SPECT) studies performed after 188Re selective internal radiation therapy when accurate correction methods are employed in image reconstruction. Our quantitative image reconstruction algorithm includes corrections for attenuation, resolution degradations and scatter as well as a window-based compensation for contamination. The procedure has been validated using four phantom experiments containing an 18 ml cylindrical source (82-93 MBq of 188Re activity) simulating a liver tumor. In addition, we applied our approach to post-therapy SPECT studies of ten patients with progressive primary or metastatic liver carcinomas. Our quantitative algorithm accurately (within 9%) recovered 188Re activity from four phantom experiments. In addition, for two patients that received three scans, deviations remained consistent between the measured and the reconstructed activities that were determined from studies with differing severity of the dead-time effect. The analysis of absorbed doses for patient studies allowed us to hypothesize that D90 (the minimum dose received by 90% of the tumor volume) may be a reliable metric relating therapy outcomes to the calculated doses. Among several considered metrics, only D90 showed statistically significant correlation with the overall survival.
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Affiliation(s)
- S Shcherbinin
- Medical Imaging Research Group, University of British Columbia, 366-828 West 10th Avenue, Vancouver BC, V5Z 1M9, Canada
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Traino AC, Marcatili S, Avigo C, Sollini M, Erba PA, Mariani G. Dosimetry for nonuniform activity distributions: A method for the calculation of 3D absorbed-dose distribution without the use of voxelS-values, point kernels, or Monte Carlo simulations. Med Phys 2013; 40:042505. [DOI: 10.1118/1.4794473] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Mínguez P, Genolla J, Celeiro JJ, Fombellida JC. Dosimetry in differentiated thyroid carcinoma. Med Phys 2012; 40:012502. [DOI: 10.1118/1.4769426] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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