1
|
Jia H, Xue M, Li X, Zhuang M, Xie T. Patient-specific radiation dose for Chinese pediatric patients undergoing whole-body PET/CT examinations. Phys Med Biol 2024; 69:125019. [PMID: 38776955 DOI: 10.1088/1361-6560/ad4f46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 05/22/2024] [Indexed: 05/25/2024]
Abstract
Objective.To assess potential variations in the absorbed dose between Chinese and Caucasian children exposed to18F-FDG PET scan and to investigate the factors contributing to dose differences, this work employed patient-specific phantoms and our compartment model for calculating the patient-specific absorbed dose in Chinese children.Approach.Data of 29 Chinese pediatric patients undergoing whole-body18F-FDG PET/CT studies were retrospectively collected, including PET images for activity distributions and corresponding CT images for organ segmentation and phantom construction. A biokinetic compartment model was implemented to obtain cumulated activities. Absorbed radiation dose for both CT and PET component were calculated using Monte Carlo simulations. Regression models were fitted to time integrated activity coefficient (TIAC) and organ absorbed dose for each patient.Main results.TIACs of all the organs in our compartment model and the organ dose for 12 organs were correlated with patients' weight. Young children have significantly large uptake in brain compared to adults. The distinctions of anatomical and biological characteristics between Chinese and Caucasian children contribute to variations in the absorbed dose of18F-FDG PET scans. PET contributed more in organ dose than CT did in most organs, especially in brain and bladder. The average effective dose (± SD) was 4.5 mSv (± 1.12 mSv), 7.8 mSv (± 3.2 mSv) and 12.3 mSv (± 3.5 mSv) from CT, PET and their sum respectively. PET contributed 1.7 times higher than CT.Significance.To the best of our knowledge, this work represents the first attempt to estimate patient-specific radiation doses from PET/CT for Chinese pediatric patients. TIACs derived from our methodology in both age groups exhibited significant differences from the that reported in ICRP 128. Substantial differences in absorbed and effective doses were observed between Chinese and Caucasian children across all age groups. These disparities are attributed to markedly distinct anatomical and pharmacokinetic characteristics among adults and pediatric patients, and different racial groups. The application of data derived from adults to pediatric patients introduces considerable uncertainty. Our methodology offers a valuable approach not only for estimating pharmacokinetic characteristics and patient-specific radiation doses in pediatric patients undergoing18F-FDG studies but also for other cohorts with similar characteristics.
Collapse
Affiliation(s)
- Haoran Jia
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai 200032, People's Republic of China
| | - Mengjia Xue
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai 200032, People's Republic of China
| | - Xianru Li
- Department of Nuclear Medicine, Meizhou People's Hospital, Meizhou, People's Republic of China
| | - Mingzan Zhuang
- Department of Nuclear Medicine, Meizhou People's Hospital, Meizhou, People's Republic of China
| | - Tianwu Xie
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai 200032, People's Republic of China
| |
Collapse
|
2
|
Ferreira CV, Mendes BM, Paixão L, Lima TV, Santos-Oliveira R, Fonseca TC. Calculation of absorbed dose in paediatric phantoms using Monte Carlo techniques for 18F-FDG and 99mTc-DMSA and the new TIAC. Appl Radiat Isot 2022; 191:110526. [DOI: 10.1016/j.apradiso.2022.110526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 09/27/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022]
|
3
|
Plyku D, Ghaly M, Li Y, Brown JL, O'Reilly S, Khamwan K, Goodkind AB, Sexton-Stallone B, Cao X, Zurakowski D, Fahey FH, Treves ST, Bolch WE, Frey EC, Sgouros G. Renal 99mTc-DMSA pharmacokinetics in pediatric patients. EJNMMI Phys 2021; 8:53. [PMID: 34283316 PMCID: PMC8292521 DOI: 10.1186/s40658-021-00401-7] [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: 10/05/2020] [Accepted: 07/05/2021] [Indexed: 11/10/2022] Open
Abstract
Abstract 99mTc-DMSA is one of the most commonly used pediatric nuclear medicine imaging agents. Nevertheless, there are no pharmacokinetic (PK) models for 99mTc-DMSA in children, and currently available pediatric dose estimates for 99mTc-DMSA use pediatric S values with PK data derived from adults. Furthermore, the adult PK data were collected in the mid-70’s using quantification techniques and instrumentation available at the time. Using pediatric imaging data for DMSA, we have obtained kinetic parameters for DMSA that differ from those applicable to adults. Methods We obtained patient data from a retrospective re-evaluation of clinically collected pediatric SPECT images of 99mTc-DMSA in 54 pediatric patients from Boston’s Children Hospital (BCH), ranging in age from 1 to 16 years old. These were supplemented by prospective data from twenty-three pediatric patients (age range: 4 months to 6 years old). Results In pediatric patients, the plateau phase in fractional kidney uptake occurs at a fractional uptake value closer to 0.3 than the value of 0.5 reported by the International Commission on Radiological Protection (ICRP) for adult patients. This leads to a 27% lower time-integrated activity coefficient in pediatric patients than in adults. Over the age range examined, no age dependency in uptake fraction at the clinical imaging time was observed. Female pediatric patients had a 17% higher fractional kidney uptake at the clinical imaging time than males (P < 0.001). Conclusions Pediatric 99mTc-DMSA kinetics differ from those reported for adults and should be considered in pediatric patient dosimetry. Alternatively, the differences obtained in this study could reflect improved quantification methods and the need to re-examine DMSA kinetics in adults. Supplementary Information The online version contains supplementary material available at 10.1186/s40658-021-00401-7.
Collapse
Affiliation(s)
- Donika Plyku
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Michael Ghaly
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Ye Li
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Justin L Brown
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Shannon O'Reilly
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Kitiwat Khamwan
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.,Department of Radiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
| | - Alison B Goodkind
- Division of Nuclear Medicine and Molecular Imaging, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Briana Sexton-Stallone
- Division of Nuclear Medicine and Molecular Imaging, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Xinhua Cao
- Division of Nuclear Medicine and Molecular Imaging, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - David Zurakowski
- Departments of Anesthesiology and Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Frederic H Fahey
- Division of Nuclear Medicine and Molecular Imaging, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - S Ted Treves
- Division of Nuclear Medicine and Molecular imaging, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Wesley E Bolch
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Eric C Frey
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - George Sgouros
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
4
|
Schmall JP, Surti S, Otero HJ, Servaes S, Karp JS, States LJ. Investigating Low-Dose Image Quality in Whole-Body Pediatric 18F-FDG Scans Using Time-of-Flight PET/MRI. J Nucl Med 2020; 62:123-130. [DOI: 10.2967/jnumed.119.240127] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 05/07/2020] [Indexed: 12/20/2022] Open
|
5
|
Abstract
In this review, we discuss molecular brain imaging studies using positron emission tomography (PET) with 2-deoxy-2(18F)fluoro-d-glucose (FDG) in human newborns and infants, and illustrate how this technology can be applied to probe the neuropathophysiology of neonatal neurologic disorders. PET studies have been difficult to perform in sick babies because of patient transportation issues and suboptimal spatial resolution. With approval from the FDA and the institutional review board, we modified and installed the Focus 220 animal microPET scanner (Concorde Microsystems, Knoxville, TN) directly in our neonatal intensive care unit in Children's Hospital of Michigan and verified the high spatial resolution (<2 mm full-width-at-half-maximum) of this microPET. The neonatal pattern of glucose metabolism is very consistent, with the highest degree of activity in primary sensory and motor cortex, medial temporal region, thalamus, brain stem, and cerebellar vermis. Prior studies have shown that increases of glucose utilization are seen by 2 to 3 months in the parietal, temporal, cingulate, and primary visual cortex; basal ganglia; and cerebellar hemispheres. Between 6 and 8 months, lateral and inferior frontal cortex becomes more functionally active and, eventually, between 8 and 12 months, the dorsal and medial frontal regions also show a maturational increase. These findings are consistent with the physical, behavioral, and cognitive maturation of the infant. At birth, metabolic rates of glucose utilization in cortex are about 30% lower than in adults but rapidly rise such that, by 3 years, the cerebral cortical rates exceed adult rates by more than 2-fold. At around puberty, the rates for cerebral cortex begin to decline and gradually reach adult values by 16-18 years. These nonlinear changes of glucose utilization indirectly reflect programed periods of synaptic proliferation and pruning in the brain. Positron emission tomographic (PET) imaging of GABAA receptors (using 11C-flumazenil) in newborns also show a pattern very different from adults, with high binding in amygdala-hippocampus, sensory-motor cortex, thalamus, brain stem, and basal ganglia, in that order. We speculate that the early development of amygdala/hippocampus prepares the baby for bonding, attachment, and memory, and the deprivation of such experiences during a sensitive period results in malfunction of these networks and psychopathology, as has been shown in studies on severely socioemotionally deprived children. Recently developed hybrid PET/magnetic resonance (MR) scanners allow the simultaneous acquisition of PET and MR data sets with advanced applications. These devices are particularly advantageous for scanning babies and infants because of the high spatial resolution, automated coregistration of anatomical and functional images and, in the case of need for sedation, maximal data acquired in 1 session.
Collapse
Affiliation(s)
- Harry T Chugani
- 1 Pediatric Neurology, Nemours Neuroscience Center, Alfred I. duPont Hospital for Children, Wilmington, DE, USA.,2 Pediatrics and Neurology, Sidney Kimmel College of Medicine at Thomas Jefferson University, Philadelphia, PA, USA
| |
Collapse
|
6
|
Khamwan K, O'Reilly SE, Plyku D, Goodkind A, Josefsson A, Cao X, Fahey FH, Treves ST, Bolch WE, Sgouros G. Re-evaluation of pediatric 18F-FDG dosimetry: Cristy-Eckerman versus UF/NCI hybrid computational phantoms. Phys Med Biol 2018; 63:165012. [PMID: 30022768 DOI: 10.1088/1361-6560/aad47a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Because of the concerns associated with radiation exposure at a young age, there is an increased interest in pediatric absorbed dose estimates for imaging agents. Almost all reported pediatric absorbed dose estimates, however, have been determined using adult pharmacokinetic data with radionuclide S values that take into account the anatomical differences between adults and children based upon the older Cristy-Eckerman (C-E) stylized phantoms. In this work, we use pediatric model-derived pharmacokinetics to compare absorbed dose and effective dose estimates for 18F-FDG in pediatric patients using S values generated from two different geometries of computational phantoms. Time-integrated activity coefficients of 18F-FDG in brain, lungs, heart wall, kidneys and liver, retrospectively, calculated from 35 pediatric patients at the Boston's Children Hospital were used. The absorbed dose calculation was performed in accordance with the Medical Internal Radiation Dose method using S values generated from the University of Florida/National Cancer Institute (UF/NCI) hybrid phantoms, as well as those from C-E stylized computational phantoms. The effective dose was computed using tissue-weighting factors from ICRP Publication 60 and ICRP Publication 103 for the C-E and UF/NCI, respectively. Substantial differences in the absorbed dose estimates between UF/NCI hybrid pediatric phantoms and the C-E stylized phantoms were found for the lungs, ovaries, red bone marrow and urinary bladder wall. Large discrepancies in the calculated dose values were observed in the bone marrow; ranging between -26% to +199%. The effective doses computed by the UF/NCI hybrid phantom S values were slightly different than those seen using the C-E stylized phantoms with percent differences of -0.7%, 2.9% and 2.5% for a newborn, 1 year old and 5 year old, respectively. Differences in anatomical modeling features among computational phantoms used to perform Monte Carlo-based photon and electron transport simulations for 18F, and very likely for other radionuclides, impact internal organ dosimetry computations for pediatric nuclear medicine studies.
Collapse
Affiliation(s)
- Kitiwat Khamwan
- The Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, United States of America. Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. Chulalongkorn University Biomedical Imaging Group, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Fahey FH, Goodkind AB, Plyku D, Khamwan K, O'Reilly SE, Cao X, Frey EC, Li Y, Bolch WE, Sgouros G, Treves ST. Dose Estimation in Pediatric Nuclear Medicine. Semin Nucl Med 2017; 47:118-125. [PMID: 28237000 PMCID: PMC5777684 DOI: 10.1053/j.semnuclmed.2016.10.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The practice of nuclear medicine in children is well established for imaging practically all physiologic systems but particularly in the fields of oncology, neurology, urology, and orthopedics. Pediatric nuclear medicine yields images of physiologic and molecular processes that can provide essential diagnostic information to the clinician. However, nuclear medicine involves the administration of radiopharmaceuticals that expose the patient to ionizing radiation and children are thought to be at a higher risk for adverse effects from radiation exposure than adults. Therefore it may be considered prudent to take extra care to optimize the radiation dose associated with pediatric nuclear medicine. This requires a solid understanding of the dosimetry associated with the administration of radiopharmaceuticals in children. Models for estimating the internal radiation dose from radiopharmaceuticals have been developed by the Medical Internal Radiation Dosimetry Committee of the Society of Nuclear Medicine and Molecular Imaging and other groups. But to use these models accurately in children, better pharmacokinetic data for the radiopharmaceuticals and anatomical models specifically for children need to be developed. The use of CT in the context of hybrid imaging has also increased significantly in the past 15 years, and thus CT dosimetry as it applies to children needs to be better understood. The concept of effective dose has been used to compare different practices involving radiation on a dosimetric level, but this approach may not be appropriate when applied to a population of children of different ages as the radiosensitivity weights utilized in the calculation of effective dose are not specific to children and may vary as a function of age on an organ-by-organ bias. As these gaps in knowledge of dosimetry and radiation risk as they apply to children are filled, more accurate models can be developed that allow for better approaches to dose optimization. In turn, this will lead to an overall improvement in the practice of pediatric nuclear medicine by providing excellent diagnostic image quality at the lowest radiation dose possible.
Collapse
Affiliation(s)
- Frederic H Fahey
- Department of Radiology, Boston Children's Hospital, Boston, MA; Department of Radiology, Harvard Medical School, Boston, MA.
| | | | - Donika Plyku
- The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD
| | - Kitiwat Khamwan
- The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD; Department of Radiology, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
| | - Shannon E O'Reilly
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL
| | - Xinhua Cao
- Department of Radiology, Boston Children's Hospital, Boston, MA
| | - Eric C Frey
- The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD
| | - Ye Li
- The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD
| | - Wesley E Bolch
- Advanced Laboratory for Radiation Dosimetry Studies (ALRADS), J. Crayton, Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL
| | - George Sgouros
- The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD
| | - S Ted Treves
- Department of Radiology, Brigham and Women's Hospital, Boston, MA; The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, School of Medicine, Baltimore, MD
| |
Collapse
|