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Yamamoto S, Okumura S, Watabe T, Ikeda H, Kanai Y, Toshito T, Komori M, Ogata Y, Kato K, Hatazawa J. Development of a prototype Open-close positron emission tomography system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:084301. [PMID: 26329212 DOI: 10.1063/1.4929329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We developed a prototype positron emission tomography (PET) system based on a new concept called Open-close PET, which has two modes: open and close-modes. In the open-mode, the detector ring is separated into two halved rings and subject is imaged with the open space and projection image is formed. In the close-mode, the detector ring is closed to be a regular circular ring, and the subject can be imaged without an open space, and so reconstructed images can be made without artifacts. The block detector of the Open-close PET system consists of two scintillator blocks that use two types of gadolinium orthosilicate (GSO) scintillators with different decay times, angled optical fiber-based image guides, and a flat panel photomultiplier tube. The GSO pixel size was 1.6 × 2.4 × 7 mm and 8 mm for fast (35 ns) and slow (60 ns) GSOs, respectively. These GSOs were arranged into an 11 × 15 matrix and optically coupled in the depth direction to form a depth-of-interaction detector. The angled optical fiber-based image guides were used to arrange the two scintillator blocks at 22.5° so that they can be arranged in a hexadecagonal shape with eight block detectors to simplify the reconstruction algorithm. The detector ring was divided into two halves to realize the open-mode and set on a mechanical stand with which the distance between the two parts can be manually changed. The spatial resolution in the close-mode was 2.4-mm FWHM, and the sensitivity was 1.7% at the center of the field-of-view. In both the close- and open-modes, we made sagittal (y-z plane) projection images between the two halved detector rings. We obtained reconstructed and projection images of (18)F-NaF rat studies and proton-irradiated phantom images. These results indicate that our developed Open-close PET is useful for some applications such as proton therapy as well as other applications such as molecular imaging.
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Onishi H, Hatazawa J, Nakagawara J, Ito K, Ha-Kawa SK, Masuda Y, Sugibayashi K, Takahashi M, Kikuchi K, Katsuta N. Impact of injected dose and acquisition time on a normal database by use of 3D-SSP in SPECT images: quantitative simulation studies. Radiol Phys Technol 2015; 8:224-31. [DOI: 10.1007/s12194-015-0311-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 10/23/2022]
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Isohashi K, Tatsumi M, Kato H, Fukushima K, Maeda T, Watabe T, Shimosegawa E, Kanakura Y, Hatazawa J. Prognostic Value of FDG-PET, Based on the Revised Response Criteria, in Patients with Malignant Lymphoma: A Comparison with CT/MRI Evaluations, Based on the International Working Group/Cotswolds Meeting Criteria. ASIA OCEANIA JOURNAL OF NUCLEAR MEDICINE & BIOLOGY 2015; 3:91-8. [PMID: 27408888 PMCID: PMC4937646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Post-treatment evaluations by CT/MRI (based on the International Working Group/Cotswolds meeting guidelines) and PET (based on Revised Response Criteria), were examined in terms of progression-free survival (PFS) in patients with malignant lymphoma (ML). METHODS 79 patients, undergoing CT/MRI for the examination of suspected lesions and whole-body PET/CT before and after therapy, were included in the study during April 2007-January 2013. The relationship between post-treatment evaluations (CT/MRI and PET) and PFS during the follow-up period was examined, using Kaplan-Meier survival analysis. The patients were grouped according to the histological type into Hodgkin's lymphoma (HL), diffuse large B-cell lymphoma (DLBCL), and other histological types. The association between post-treatment evaluations (PET or PET combined with CT/MRI) and PFS was examined separately. Moreover, the relationship between disease recurrence and serum soluble interleukin-2 receptor, lactic dehydrogenase, and C-reactive protein levels was evaluated before and after the treatment. RESULTS Patients with incomplete remission on both CT/MRI and PET had a significantly shorter PFS, compared to patients with complete remission on both CT/MRI and PET and those exhibiting incomplete remission on CT/MRI and complete remission on PET (P<0.001). Post-treatment PET evaluations were strongly correlated with patient outcomes in cases with HL or DLBCL (P<0.01) and other histological types (P<0.001). In patients with HL or DLBCL, incomplete remission on both CT/MRI and PET was associated with a significantly shorter PFS, compared to patients with complete remission on both CT/MRI and PET (P<0.05) and those showing incomplete remission on CT/MRI and complete remission on PET (P<0.01). In patients with other histological types, incomplete remission on both CT/MRI and PET was associated with a significantly shorter PFS, compared to cases with complete remission on both CT/MRI and PET (P<0.001). None of the serum parameters differed significantly between recurrent and non-recurrent cases. CONCLUSION Post-treatment PET evaluations were well correlated with the outcomes of patients with ML, exhibiting FDG uptake. Among patients with HL or DLBCL, a post-treatment complete remission on PET was predictive of a relatively long PFS. For predicting the prognosis of patients with other histological types, a combination of CT/MRI and PET, rather than PET alone, is recommended.
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Hanaoka K, Watabe T, Naka S, Kanai Y, Ikeda H, Horitsugi G, Kato H, Isohashi K, Shimosegawa E, Hatazawa J. FBPA PET in boron neutron capture therapy for cancer: prediction of (10)B concentration in the tumor and normal tissue in a rat xenograft model. EJNMMI Res 2014; 4:70. [PMID: 25621196 PMCID: PMC4293470 DOI: 10.1186/s13550-014-0070-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 11/27/2014] [Indexed: 11/10/2022] Open
Abstract
Background Boron neutron capture therapy (BNCT) is a molecular radiation treatment based on the 10B (n, α) 7Li nuclear reaction in cancer cells, in which delivery of 10B by 4-borono-phenylalanine conjugated with fructose (BPA-fr) to the cancer cells is of critical importance. The PET tracer 4-borono-2-18 F-fluoro-phenylalanine (FBPA) has been used to predict the accumulation of BPA-fr before BNCT. However, because of the difference in chemical structure between BPA-fr and FBPA and the difference in the dose administered between BPA-fr (therapeutic dose) and FBPA (tracer dose), the predictive value of FBPA PET for BPA-fr accumulation in the tumor and normal tissues is not yet clearly proven. We conducted this study to validate FBPA PET as a useful test to predict the accumulation of BPA-fr in the tumor and normal tissues before BNCT. Methods RGC-6 rat glioma cells (1.9 × 107) were implanted subcutaneously in seven male F344 rats. On day 20 after the tumor implantation, dynamic PET scan was performed on four rats after injection of FBPA for 1 h. Whole-body PET/CT was performed 1 h after intravenous injection of the FBPA solution (30.5 ± 0.7 MBq, 1.69 ± 1.21 mg/kg). PET accumulation of FBPA in the tumor tissue and various normal tissues was estimated as a percentage of the injected dose per gram (%ID/g). One hour after the PET/CT scan, BPA-fructose (167.32 ± 18.65 mg/kg) was injected intravenously, and the rats were dissected 1 h after the BPA-fr injection. The absolute concentration of 10B in the autopsied tissues and blood was measured by inductively coupled plasma optical emission spectrometry (ICP-OES). Results The highest absolute concentration of 10B determined by ICP-OES was found in the kidney (4.34 ± 0.84 %ID/g), followed by the pancreas (2.73 ± 0.63 %ID/g), and the tumor (1.44 ± 0.44 %ID/g). A significant positive correlation was found between the accumulation levels of BPA-fr and FBPA (r = 0.91, p < 0.05). Conclusions FBPA PET can reliably predict accumulation of BPA-fr in the tumor as well as normal tissues. Electronic supplementary material The online version of this article (doi:10.1186/s13550-014-0070-2) contains supplementary material, which is available to authorized users.
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Yamauchi M, Imabayashi E, Matsuda H, Nakagawara J, Takahashi M, Shimosegawa E, Hatazawa J, Suzuki M, Iwanaga H, Fukuda K, Iihara K, Iida H. Quantitative assessment of rest and acetazolamide CBF using quantitative SPECT reconstruction and sequential administration of (123)I-iodoamphetamine: comparison among data acquired at three institutions. Ann Nucl Med 2014; 28:836-50. [PMID: 25001261 PMCID: PMC4244544 DOI: 10.1007/s12149-014-0879-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 06/29/2014] [Indexed: 10/27/2022]
Abstract
PURPOSE A recently developed technique which reconstructs quantitative images from original projection data acquired using existing single-photon emission computed tomography (SPECT) devices enabled quantitative assessment of cerebral blood flow (CBF) at rest and after acetazolamide challenge. This study was intended to generate a normal database and to investigate its inter-institutional consistency. METHODS The three institutions carried out a series of SPECT scanning on 32 healthy volunteers, following a recently proposed method that involved dual administration of (123)I-iodoamphetamine during a single SPECT scan. Intra-institute and inter-institutional variations of regional CBF values were evaluated both at rest and after acetazolamide challenge. Functional images were pooled for both rest and acetazolamide CBF, and inter-institutional difference was evaluated among these images using two independent software programs. RESULTS Quantitative assessment of CBF images at rest and after acetazolamide was successfully achieved with the given protocol in all institutions. Intra-institutional variation of CBF values at rest and after acetazolamide was consistent with previously reported values. Quantitative CBF values showed no significant difference among institutions in all regions, except for a posterior cerebral artery region after acetazolamide challenge in one institution which employed SPECT device with lowest spatial resolution. Pooled CBF images at rest and after acetazolamide generated using two software programs showed no institutional differences after equalization of the spatial resolution. CONCLUSIONS SPECT can provide reproducible images from projection data acquired using different SPECT devices. A common database acquired at different institutions may be shared among institutions, if images are reconstructed using a quantitative reconstruction program, and acquired by following a standardized protocol.
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Kinoshita M, Arita H, Kagawa N, Watanabe Y, Hatazawa J, Hashimoto N, Yoshimine T. NI-48 * COMPARISON OF DTI AND 11C-METHIONINE PET FOCUSING ON THEIR PREDICTIVE VALUES OF TUMOR CELL DENSITY IN GLIOMAS. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou264.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Watabe T, Naka S, Ikeda H, Horitsugi G, Kanai Y, Isohashi K, Ishibashi M, Kato H, Shimosegawa E, Watabe H, Hatazawa J. Distribution of intravenously administered acetylcholinesterase inhibitor and acetylcholinesterase activity in the adrenal gland: 11C-donepezil PET study in the normal rat. PLoS One 2014; 9:e107427. [PMID: 25225806 PMCID: PMC4166663 DOI: 10.1371/journal.pone.0107427] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/10/2014] [Indexed: 12/30/2022] Open
Abstract
Purpose Acetylcholinesterase (AChE) inhibitors have been used for patients with Alzheimer's disease. However, its pharmacokinetics in non-target organs other than the brain has not been clarified yet. The purpose of this study was to evaluate the relationship between the whole-body distribution of intravenously administered 11C-Donepezil (DNP) and the AChE activity in the normal rat, with special focus on the adrenal glands. Methods The distribution of 11C-DNP was investigated by PET/CT in 6 normal male Wistar rats (8 weeks old, body weight = 220±8.9 g). A 30-min dynamic scan was started simultaneously with an intravenous bolus injection of 11C-DNP (45.0±10.7 MBq). The whole-body distribution of the 11C-DNP PET was evaluated based on the Vt (total distribution volume) by Logan-plot analysis. A fluorometric assay was performed to quantify the AChE activity in homogenized tissue solutions of the major organs. Results The PET analysis using Vt showed that the adrenal glands had the 2nd highest level of 11C-DNP in the body (following the liver) (13.33±1.08 and 19.43±1.29 ml/cm3, respectively), indicating that the distribution of 11C-DNP was the highest in the adrenal glands, except for that in the excretory organs. The AChE activity was the third highest in the adrenal glands (following the small intestine and the stomach) (24.9±1.6, 83.1±3.0, and 38.5±8.1 mU/mg, respectively), indicating high activity of AChE in the adrenal glands. Conclusions We demonstrated the whole-body distribution of 11C-DNP by PET and the AChE activity in the major organs by fluorometric assay in the normal rat. High accumulation of 11C-DNP was observed in the adrenal glands, which suggested the risk of enhanced cholinergic synaptic transmission by the use of AChE inhibitors.
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Yamamoto S, Hamamura F, Watabe T, Ikeda H, Kanai Y, Watabe H, Kato K, Ogata Y, Hatazawa J. Development of a PET/Cerenkov-light hybrid imaging system. Med Phys 2014; 41:092504. [DOI: 10.1118/1.4893535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Watabe T, Shimosegawa E, Kato H, Isohashi K, Ishibashi M, Tatsumi M, Kitagawa K, Fujinaka T, Yoshimine T, Hatazawa J. Paradoxical reduction of cerebral blood flow after acetazolamide loading: a hemodynamic and metabolic study with (15)O PET. Neurosci Bull 2014; 30:845-56. [PMID: 25096497 DOI: 10.1007/s12264-013-1459-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/23/2014] [Indexed: 10/25/2022] Open
Abstract
Paradoxical reduction of cerebral blood flow (CBF) after administration of the vasodilator acetazolamide is the most severe stage of cerebrovascular reactivity failure and is often associated with an increased oxygen extraction fraction (OEF). In this study, we aimed to reveal the mechanism underlying this phenomenon by focusing on the ratio of CBF to cerebral blood volume (CBV) as a marker of regional cerebral perfusion pressure (CPP). In 37 patients with unilateral internal carotid or middle cerebral arterial (MCA) steno-occlusive disease and 8 normal controls, the baseline CBF (CBF(b)), CBV, OEF, cerebral oxygen metabolic rate (CMRO2), and CBF after acetazolamide loading in the anterior and posterior MCA territories were measured by (15)O positron emission tomography. Paradoxical CBF reduction was found in 28 of 74 regions (18 of 37 patients) in the ipsilateral hemisphere. High CBF(b) (> 47.6 mL/100 mL/min, n = 7) was associated with normal CBF(b)/CBV, increased CBV, decreased OEF, and normal CMRO2. Low CBF(b) (< 31.8 mL/100 mL/min, n = 9) was associated with decreased CBF(b)/CBV, increased CBV, increased OEF, and decreased CMRO2. These findings demonstrated that paradoxical CBF reduction is not always associated with reduction of CPP, but partly includes high-CBF(b) regions with normal CPP, which has not been described in previous studies.
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Hanamoto A, Tatsumi M, Takenaka Y, Hamasaki T, Yasui T, Nakahara S, Yamamoto Y, Seo Y, Isohashi F, Ogawa K, Hatazawa J, Inohara H. Volumetric PET/CT parameters predict local response of head and neck squamous cell carcinoma to chemoradiotherapy. Cancer Med 2014; 3:1368-76. [PMID: 25045041 PMCID: PMC4302687 DOI: 10.1002/cam4.295] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/09/2014] [Accepted: 06/09/2014] [Indexed: 11/25/2022] Open
Abstract
It is not well established whether pretreatment 18F-FDG PET/CT can predict local response of head and neck squamous cell carcinoma (HNSCC) to chemoradiotherapy (CRT). We examined 118 patients: 11 with nasopharyngeal cancer (NPC), 30 with oropharyngeal cancer (OPC), and 77 with laryngohypopharyngeal cancer (LHC) who had completed CRT. PET/CT parameters of primary tumor, including metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum and mean standardized uptake value (SUVmax and SUVmean), were correlated with local response, according to primary site and human papillomavirus (HPV) status. Receiver-operating characteristic analyses were made to access predictive values of the PET/CT parameters, while logistic regression analyses were used to identify independent predictors. Area under the curve (AUC) of the PET/CT parameters ranged from 0.53 to 0.63 in NPC and from 0.50 to 0.54 in OPC. HPV-negative OPC showed AUC ranging from 0.51 to 0.58, while all of HPV-positive OPCs showed complete response. In contrast, AUC ranged from 0.71 to 0.90 in LHC. Moreover, AUCs of MTV and TLG were significantly higher than those of SUVmax and SUVmean (P < 0.01). After multivariate analysis, high MTV >25.0 mL and high TLG >144.8 g remained as independent, significant predictors of incomplete response compared with low MTV (odds ratio [OR], 13.4; 95% confidence interval [CI], 2.5–72.9; P = 0.003) and low TLG (OR, 12.8; 95% CI, 2.4–67.9; P = 0.003), respectively. In conclusion, predictive efficacy of pretreatment 18F-FDG PET/CT varies with different primary sites and chosen parameters. Local response of LHC is highly predictable by volume-based PET/CT parameters.
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Tamura M, Matsui H, Hirohara S, Kakiuchi K, Tanihara M, Takahashi N, Nakai K, Kanai Y, Watabe H, Hatazawa J. Rapid Synthesis of 62Zn-Labeled S-Glycosylated Porphyrin as Positron Emission Tomography Tracers for In Vivo PET Imaging. CHEM LETT 2014. [DOI: 10.1246/cl.140056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Tamura M, Matsui H, Hirohara S, Kakiuchi K, Tanihara M, Takahashi N, Nakai K, Kanai Y, Watabe H, Hatazawa J. Selective accumulation of [62Zn]-labeled glycoconjugated porphyrins as multi-functional positron emission tomography tracers in cancer cells. Bioorg Med Chem 2014; 22:2563-70. [DOI: 10.1016/j.bmc.2014.02.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 02/14/2014] [Accepted: 02/14/2014] [Indexed: 02/05/2023]
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Miyata H, Yamasaki M, Takahashi T, Murakami K, Tanaka K, Yukinori K, Nakajima K, Takiguchi S, Morii E, Hatazawa J, Mori M, Doki Y. Determinants of response to neoadjuvant chemotherapy for esophageal cancer using 18F-fluorodeoxiglucose positron emission tomography (18F-FDG-PET). Ann Surg Oncol 2013; 21:575-82. [PMID: 24201746 DOI: 10.1245/s10434-013-3343-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Indexed: 12/25/2022]
Abstract
BACKGROUND (18)F-FDG-PET is potentially useful for evaluating response to neoadjuvant therapy for esophageal cancer. However, the optimal (18)F-FDG-PET parameter for evaluating the response to therapy and survival has not been established. This study aimed to select the best of the two parameters of fluorodeoxyglucose ((18)F-FDG)-positron emission tomography (PET): decreased ratio of maximal standardized uptake (SUVmax-DR) or absolute value of posttreatment SUVmax (post-SUVmax), in predicting response and survival of patients with esophageal cancer who underwent neoadjuvant chemotherapy. METHODS The study subjects were 211 consecutive patients with esophageal cancer who received neoadjuvant chemotherapy followed by surgery. (18)F-FDG-PET was performed before and 2-3 weeks after completion of neoadjuvant chemotherapy in assessment with pretreatment SUVmax (pre-SUVmax), post-SUVmax and SUVmax-DR. RESULTS The mean SUVmax decreased during neoadjuvant chemotherapy from 11.4 to 5.8, and the mean SUVmax-DR was 49.4%. Both post-SUVmax and SUVmax-DR correlated significantly with pathological response, although neither post-SUVmax nor SUVmax-DR could distinguish pathological complete response from pathological good response. The 5-year survival rate was significantly higher in patients with SUVmax-DR of >50% than those with <50% (56.5 vs. 39.6 %, p = 0.0137), and also significantly higher in patients with post-SUVmax of <3.5 than those with >3.5 (62.2 vs. 35.1%, p < 0.0001). Multivariate analysis identified post-SUVmax value, but not SUVmax-DR, as an independent prognostic factor in patients who underwent neoadjuvant chemotherapy. CONCLUSIONS Post-SUVmax is more useful for predicting survival of patients with esophageal cancer who undergo neoadjuvant therapy followed by surgery, although both SUVmax-DR and post-SUVmax equally correlate with pathological response.
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Yamamoto S, Watabe H, Kanai Y, Watabe T, Kato K, Hatazawa J. Development of an ultrahigh resolution Si-PM based PET system for small animals. Phys Med Biol 2013; 58:7875-88. [PMID: 24145308 DOI: 10.1088/0031-9155/58/21/7875] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since a high resolution PET system is needed for small animal imaging, especially for mouse studies, we developed a new small animal PET system that decreased the size of the scintillators to less than 1 mm. Our developed PET system used 0.5 × 0.7 × 5 mm(3) LYSO pixels arranged in an 11 × 13 matrix to form a block with a 0.1 mm BaSO4 reflector between the pixels. Two LYSO blocks were optically coupled to two optical fiber based angled image guides. These LYSO blocks and image guides were coupled to a Si-PM array (Hamamatsu MPPC S11064-050P) to form a block detector. Eight block detectors (16 LYSO blocks) were arranged in a 34 mm inner diameter ring to form a small animal PET system. The block detector showed good separation for the 22 × 13 LYSO pixels in the two-dimensional position histogram. The energy resolution was 20% full-with at half-maximum (FWHM) for 511 keV gamma photons. The transaxial resolution reconstructed by filtered backprojection was 0.71 to 0.75 mm FWHM and the axial resolution was 0.70 mm. The point source sensitivity was 0.24% at the central axial field-of-view. High resolution mouse images were obtained using our PET system. The developed ultrahigh resolution PET system showed attractive images for small animal studies and has a potential to provide new findings in molecular imaging researches.
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Toita R, Kanai Y, Watabe H, Nakao K, Yamamoto S, Hatazawa J, Akashi M. Biodistribution of 125I-labeled polymeric vaccine carriers after subcutaneous injection. Bioorg Med Chem 2013; 21:5310-5. [DOI: 10.1016/j.bmc.2013.06.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 06/06/2013] [Accepted: 06/07/2013] [Indexed: 11/29/2022]
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Hanamoto A, Takenaka Y, Shimosegawa E, Ymamamoto Y, Yoshii T, Nakahara S, Hatazawa J, Inohara H. Limitation of 2-deoxy-2-[F-18]fluoro-d-glucose positron emission tomography (FDG-PET) to detect early synchronous primary cancers in patients with untreated head and neck squamous cell cancer. Ann Nucl Med 2013; 27:880-5. [DOI: 10.1007/s12149-013-0765-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 08/14/2013] [Indexed: 12/22/2022]
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Hayashi T, Suzuki A, Hatazawa J, Hadeishi H, Shirane R, Tominaga T, Yasui N. Post-operative changes of cerebral circulation and metabolism in the acute stage of low-grade aneurysmal subarachnoid hemorrhage. Neurol Res 2013; 30:678-83. [DOI: 10.1179/174313208x291676] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Shimosegawa E, Fujino K, Kato H, Hatazawa J. Quantitative CBF measurement using an integrated SPECT/CT system: validation of three-dimensional ordered-subset expectation maximization and CT-based attenuation correction by comparing with O-15 water PET. Ann Nucl Med 2013; 27:822-33. [PMID: 23824783 DOI: 10.1007/s12149-013-0752-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 06/20/2013] [Indexed: 11/30/2022]
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Isohashi K, Shimosegawa E, Kato H, Kanai Y, Naka S, Fujino K, Watabe H, Hatazawa J. Optimization of [11C]methionine PET study: appropriate scan timing and effect of plasma amino acid concentrations on the SUV. EJNMMI Res 2013; 3:27. [PMID: 23587060 PMCID: PMC3637362 DOI: 10.1186/2191-219x-3-27] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 03/24/2013] [Indexed: 11/18/2022] Open
Abstract
Background [11C]methionine (MET) has been used to monitor amino acid metabolism in tumors, the pancreas, liver, and myocardium. The aim of the present study was to standardize [11C]MET positron emission tomography (PET) by optimizing the timing of initiation of the scan and applying correction to the plasma concentrations of neutral amino acids (NAAs), where necessary. Methods Sequential whole-body MET PET/computed tomography (CT) was performed in 11 normal adults after they had fasted for at least 4 h. After whole-body CT for attenuation correction and intravenous bolus injection of MET, the subjects were scanned from the parietal to the groin. The scanning was repeated six to seven times. Decay of radioactivity during the PET scan was corrected to the time of initiation of the first scan. The standardized uptake values (SUVs) were evaluated in various organs by setting regions of interest on the tomographic images. Plasma concentrations of NAAs were examined in relation to the SUV values. Results The SUVs in the pancreas reached their plateau from 6.5 to 11 min after the MET injection, and in the brain, lung, and myocardium, they reached their plateau from 19.6 to 24.1 min. The MET uptake in the spleen and kidney peaked early after the injection and steadily decreased thereafter. The SUVs in the liver and stomach wall rapidly increased during the first 0 to 4.5 min and gradually elevated thereafter during the scan period. Urinary radioactivity in the bladder reached its plateau from 26.1 to 30.6 min after the MET injection. There were no correlations between the plasma concentrations of NAAs and the maximal SUV in any organs. Conclusions The present study revealed the times taken to reach the plateau of MET uptake in various important organs, and little effects of the plasma neutral amino acid concentrations on the SUVs in PET studies conducted after the patients had fasted for at least 4 h. In the MET PET study, 4 h fasting period before MET administration and the scan initiation 20 min after MET administration provide the SUV values independent of scan initiation time and the plasma neutral amino acid concentrations.
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Hosomi K, Kishima H, Oshino S, Hirata M, Tani N, Maruo T, Khoo HM, Shimosegawa E, Hatazawa J, Kato A, Yoshimine T. Altered extrafocal iomazenil activity in mesial temporal lobe epilepsy. Epilepsy Res 2013; 103:195-204. [DOI: 10.1016/j.eplepsyres.2012.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 06/06/2012] [Accepted: 07/03/2012] [Indexed: 11/28/2022]
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Watabe T, Shimosegawa E, Watabe H, Kanai Y, Hanaoka K, Ueguchi T, Isohashi K, Kato H, Tatsumi M, Hatazawa J. Quantitative evaluation of cerebral blood flow and oxygen metabolism in normal anesthetized rats: 15O-labeled gas inhalation PET with MRI Fusion. J Nucl Med 2013; 54:283-90. [PMID: 23287575 DOI: 10.2967/jnumed.112.109751] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED PET with (15)O gas has been used for the quantitative measurement of cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO(2)), oxygen extraction fraction (OEF), and cerebral blood volume (CBV) in humans. However, several technical difficulties limit its use in experiments on small animals. Herein, we describe the application of the (15)O gas steady-state inhalation method for normal anesthetized rats. METHODS Eight normal male Sprague-Dawley rats (mean body weight ± SD, 268 ± 14 g) under anesthesia were investigated by (15)O-labeled gas PET. After tracheotomy, an airway tube was placed in the trachea, and the animals were connected to a ventilator (tidal volume, 3 cm(3); frequency, 60/min). The CBF and OEF were measured according to the original steady-state inhalation technique under artificial ventilation with (15)O-CO(2) and (15)O-O(2) gases delivered through the radioactive gas stabilizer. CBV was measured by (15)O-CO gas inhalation and corrected for the intravascular hemoglobin-bound (15)O-O(2). Arterial blood sampling was performed during each study to measure the radioactivity of the whole blood and plasma. MR image was performed with the same acrylic animal holder immediately after the PET. Regions of interest were placed on the whole brain of the PET images with reference to the semiautomatically coregistered PET/MR fused images. RESULTS The data acquisition time for the whole PET experiment in each rat was 73.3 ± 5.8 (range, 68-85) min. In both the (15)O-CO(2) and the (15)O-O(2) studies, the radioactivity count of the brain reached a steady state by approximately 10 min after the start of continuous inhalation of the gas. The quantitative PET data of the whole brain were as follows: CBF, 32.3 ± 4.5 mL/100 mL/min; CMRO(2), 3.23 ± 0.42 mL/100 mL/min; OEF, 64.6% ± 9.1%; and CBV, 5.05 ± 0.45 mL/100 mL. CONCLUSION Although further technical improvements may be needed, this study demonstrated the feasibility of quantitative PET measurement of CBF, OEF, and CMRO(2) using the original steady-state inhalation method of (15)O-CO(2) and (15)O-O(2) gases and measurement of CBV using the (15)O-CO gas inhalation method in the brain of normal anesthetized rats.
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Yamamoto S, Watabe H, Kato K, Hatazawa J. Performance comparison of high quantum efficiency and normal quantum efficiency photomultiplier tubes and position sensitive photomultiplier tubes for high resolution PET and SPECT detectors. Med Phys 2012; 39:6900-7. [DOI: 10.1118/1.4760991] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Yamada S, Ueguchi T, Ukai I, Nagai Y, Yamakawa M, Shimosegawa E, Shimazu T, Hatazawa J. [The potential of dual-energy virtual monochromatic imaging in reducing renal cyst pseudoenhancement: a phantom study]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2012; 68:1379-84. [PMID: 23089841 DOI: 10.6009/jjrt.2012_jsrt_68.10.1379] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Renal cyst pseudoenhancement, an artifactual increase of computed tomography (CT) attenuation for cysts with increased iodine concentrations in the renal parenchyma, complicates the classification of cysts and may thus lead to the mischaracterization of a benign non-enhancing lesion as an enhancing mass. The purpose of this study was to use a phantom model to assess the ability of dual-energy virtual monochromatic imaging to reduce renal pseudoenhancement. A water-filled cylindrical cyst model suspended in varying concentrations of iodine solution, to simulate varying levels of parenchymal enhancement, was scanned with a dual-energy CT scanner using the following three scanning protocols with different combinations of tube voltage: 80 and 140 kV; 80 and 140 kV with tin filter; and 100 and 140 kV with tin filter. Virtual monochromatic images were then synthesized for each dual-energy scan. Single-energy scan with a tube voltage of 120 kV was also performed to obtain polychromatic images as controls. Mean attenuation values (in Hounsfield units) of cyst proxies were measured on both polychromatic and virtual monochromatic images. Pseudoenhancement was considered to be present when the cyst attenuation level increased by more than 10 HU as the background iodine concentration increased from 0.0% to 0.4%, 1.5%, or 2.5%. Our results revealed that pseudoenhancement was not observed on any of the monochromatic images, but appeared on polychromatic images at a background iodine concentration of 2.5%. We thus conclude that dual-energy virtual monochromatic images have a potential to reduce renal pseudoenhancement.
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Yamamoto S, Watabe H, Kanai Y, Watabe T, Aoki M, Sugiyama E, Kato K, Hatazawa J. Development of a flexible optical fiber based high resolution integrated PET/MRI system. Med Phys 2012; 39:6660-71. [DOI: 10.1118/1.4757911] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Choi YJ, Gabikian P, Zhu F, Appelbaum DE, Wollmann RL, Lukas RV, Xu LW, Thomas RP, Lober RM, Nagpal S, Li G, Megyesi JF, Macdonald D, Chaudhary N, Berghoff AS, Spanberger T, Magerle M, Dinhof C, Woehrer A, Hackl M, Birner P, Widhalm G, Marosi C, Prayer D, Preusser M, Kamson DO, Juhasz C, Buth A, Kupsky WJ, Muzik O, Robinette NL, Barger GR, Mittal S, Kinoshita M, Hirayama R, Chiba Y, Kagawa N, Nonaka M, Kanemura Y, Kishima H, Nakajima S, Hatazawa J, Hashimoto N, Yoshimine T, Kim EH, Kim SH, Nowosielski M, Hutterer M, Putzer D, Iglseder S, Seiz M, Jacobs AH, Gobel G, Stockhammer G, Hutterer M, Nowosielski M, Putzer D, Iglseder S, Seiz M, Jacobs AH, Gobel G, Stockhammer G, Juhasz C, Buth A, Kamson DO, Kupsky WJ, Barger GR, Mittal S, Zach L, Guez D, Last D, Daniels D, Grober Y, Nissim O, Hoffman C, Nass D, Spiegelmann R, Cohen ZR, Mardor Y, Mittal S, Buth A, Kupsky WJ, Kamson DO, Barger GR, Juhasz C, Perreault S, Lober RM, Zhang GH, Hershon L, Decarie JC, Yeom K, Vogel H, Partap S, Carret AS, Fisher PG, Colen RR, Changlai T, Sathyan P, Gutman D, Zinn P, Colen RR, Kovacs A, Zinn P, Jolesz F, Colen RR, Zinn P, Asthagiri A, Vasquez R, Butman J, Wu T, Morgan K, Brewer C, King K, Zalewski C, Jeffrey Kim H, Lonser R, Akbari H, Da X, Macyszyn L, Verma R, Wolf RL, Bilello M, Melhem ER, O'Rourke DM, Davatzikos C, Liu X, Madhankumar AB, Miller PA, Duck KA, Hafenstein S, Rizk E, Sheehan JM, Connor JR, Yang QX, Fouke SJ, Weinberger K, Kelsey M, Cholleti S, Politte D, Marcus D, Boyd A, Keogh B, Benzinger T, Milchenko M, Kim L, Prior F, Kim LM, Commean P, Boyd A, Milchenko M, Politte D, Chicoine M, Rich K, Benzinger T, Marcus D, Jost S, Fatterpekar G, Raz E, Knopp E, Gruber M, Parker E, Golfinos J, Zagzag D, Parker E, Fatterpekar G, Raz E, Narayana A, Johnson G, Placantonakis D, Zagzag D, Wen Q, Essock-Burns E, Li Y, Chang S, Nelson SJ, Li Y, Larson P, Chen A, Lupo JM, Kelley D, Chang S, Nelson SJ, Li Y, Lupo JM, Parvataneni R, Lamborn K, Cha S, Chang S, Nelson SJ, Jalbert LE, Elkhaled A, Phillips JJ, Williams C, Cha S, Berger MS, Chang SM, Nelson SJ, Damek DM, Ney DE, Borges MT, Colantoni W, Bert R, Huang R, Chen C, Mukundan S, Wen P, Norden A, Andre JB, Schmiedeskamp H, Thomas RP, Feroze A, Nagpal S, Zaharchuk G, Straka M, Recht L, Bammer R, Rockhill J, Mrugala M, Fink J, Rostomily R, Link J, Muzi M, Eary J, Krohn K, Perreault S, Lober RM, Partap S, Carret AS, Fisher FG, Ellingson BM, Pope WB, Boxerman JL, Harris RJ, Lai A, Nghiemphu PL, Jeyapalan S, Safran H, Kruse CA, Liau LM, Cloughesy TF, Harris RJ, Cloughesy TF, Lai A, Nghiemphu PL, Pope WB, Ellingson BM, Elkhaled A, Phillips J, Chang SM, Cha S, Nelson SJ. CLIN-RADIOLOGY. Neuro Oncol 2012; 14:vi120-vi128. [PMCID: PMC3488790 DOI: 10.1093/neuonc/nos236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023] Open
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