Hideyuki Wakamatsu

Technetium-99m tetrofosmin for parathyroid scintigraphy: a direct comparison with 99mTc-MIBI, 201Tl, MRI and US

The aim of this study was to evaluate the efficacy and role of technetium-99m tetrofosmin for the detection of abnormal parathyroid glands to be referred for surgical treatment. Twenty-eight consecutive patients, including 25 primary and 3 secondary cases of hyperparathyroidism, were evaluated. 99mTc-tetrofosmin/99mTc-pertechnetate subtraction scintigraphy (TF/Tc) was performed on all patients, and the results were directly compared with those of 99mTc-methoxyisobutylisonitrile (MIBI)/99mTc-pertechnetate subtraction scintigraphy (MIBI/Tc), 201Tl/99mTc-pertechnetate subtraction scintigraphy (Tl/Tc), magnetic resonance imaging (MRI) and ultrasonography (US). In cases of single-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 63.2%, 68.4%, 57.9%, 55.6% and 63.2%, respectively. In cases of multi-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 41.7%, 41.7%, 37.5%, 58.3% and 54.2%, respectively. In cases of parathyroid adenoma, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 68.8%, 75.0%, 68.8%, 62.5% and 75.0%, respectively. In cases of parathyroid hyperplasia, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 40.7%, 40.7%, 33.3%, 53.8% and 48.1%, respectively. It is concluded that, for the detection of abnormal parathyroid glands, 99mTc-tetrofosmin is as useful as 99mTc-MIBI and is more useful than 201Tl.

Usefulness of rCBF analysis in diagnosing Parkinson’s disease: supplemental role with MIBG myocardial scintigraphy

Abstract123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy is a useful tool for differentiating idiopathic Parkinson’s disease (PD) from parkinsonism (PS) caused by other disorders. However, cardiac MIBG uptake is affected by various causes. Alternatively, hypoperfusion in the occipital lobe of PD is reported recently.ObjectiveThe objective is to clarify the correlation between regional cerebral blood flow (rCBF) alteration and cardiac MIBG uptake in PD. In addition, we examined whether additional brain perfusion analysis improved the differential diagnostic ability for PD from PS when compared with MIBG scintigraphy alone.MethodsForty-nine patients with PD (27 mild groups: Hoehn and Yahr stages I, II; 22 severe groups: Hoehn and Yahr stages III, IV) and 28 patients with PS participated. We compared absolute rCBF values between PD and PS. In addition, we determined correlation between MIBG parameters and each rCBF value. Finally, we compared the diagnostic ability for the differentiation of PD from PS between two diagnostic criteria, each MIBG index abnormality alone [heart-to-mediastinum ratio, H/M (E) < 1.9, H/E (D) < 1.7, washout rate > 40%] and each MIBG index abnormality or occipital lobe hypoperfusion (<36 ml/100 g per min).ResultsAbsolute rCBF value of occipital lobe was significantly lower in severe PD as compared with PS or mild PD. In the correlation analysis, rCBF of occipital lobe correlated positively with MIBG parameters (H/M). Regarding the diagnostic ability, sensitivity improved by accounting for occipital hypoperfusion as compared with MIBG indices alone. In contrast, neither specificity nor accuracy improved by adding occipital lobe analysis.ConclusionsMIBG parameters (H/M) correlated positively with occipital hypoperfusion in PD. In the differential diagnosis between PD and PS, although its usefulness might be limited, analysis of rCBF in the occipital lobe added to 123I-MIBG myocardial imaging can be recommended.

Role of gastric distention with additional water in differentiating locally advanced gastric carcinomas from physiological uptake in the stomach on 18f-fluoro-2-deoxy-d-glucose Pet

PurposeIn this study, we investigated the role of gastric distention with additional water to determine whether it is beneficial for the differentiation of locally advanced gastric carcinomas from physiological 18F-fluoro-2-deoxy-D-glucose (FDG) uptake in the stomach and to characterize the FDG uptake of gastric carcinomas by relating it to the histopathological properties of the tumours. MethodsSixteen patients with locally advanced gastric carcinomas and 20 control patients were studied by FDG-PET. After whole-body PET imaging, the patients drank 400 ml of water and then spot imaging with additional water of the stomach was performed. The final diagnosis was determined from the results of surgery. The gastric areas were divided into the upper, middle, and lower parts. The degree of FDG uptake in the stomach was qualitatively evaluated by visual grading into three degrees. For quantitative analysis, the regional tumour uptake was measured by mean standardized uptake values using a region of interest technique. ResultsIn visual analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET without additional water ingestion were 100, 50, 62, 100 and 72%, respectively, and those of PET with additional water ingestion were 88, 100, 100, 91 and 94%, respectively. Using spot imaging under the condition with additional water ingestion, four gastric carcinomas were depicted more clearly. ConclusionGastric distention as a result of patients drinking a glass of water is a simple and noninvasive method for improving the diagnostic accuracy of FDG-PET in patients with locally advanced gastric carcinoma.

Alteration of regional cerebral blood flow in patients with chronic pain--evaluation before and after epidural spinal cord stimulation.

BackgroundChronic pain is defined as intractable pain caused by abnormal pain transmission or impairment of the pain control system per se. Alteration of regional cerebral blood flow (rCBF) is known to occur under the presence of pain stimulation. Epidural spinal cord stimulation (SCS) is occasionally effective in relieving the symptom.ObjectiveThe aim of the current study is to investigate the alteration of rCBF in baseline condition and to find the association between the rCBF change and the efficacy of SCS in chronic pain.MethodsA total of 18 patients underwent Tc-99m-HMPAO SPECT before and after SCS. Analysis with three-dimensional stereo-tactic surface projections (3D-SSP) with stereo-tactic extraction estimation (SEE) software was adopted to evaluate the rCBF. We assessed the extent score of the abnormal region in each segment (rate of the coordinates with a Z-value that exceeds three kinds of threshold value 2.0, 2.5 and 3.0 in all coordinates within a segment). According to the therapeutic response defined by visual analogue scale, we categorized patients into two groups, the good responder (GR) group (n = 12) and poor responder (PR) group (n = 6). In the analysis, we compared the extent score in the following two conditions. (1)Comparison between the PR group and normal control group under both baseline condition and after SCS. (2)Comparison between the GR group and normal control group under both baseline condition and after SCS.Results(1)In the PR group, increased rCBF was observed in left thalamus, bilateral precuneus and bilateral cerebellum under the baseline condition. After SCS, the range of these increased rCBF areas localized but remained. Decrease of rCBF was noted in bilateral subcallosal gyrus, superior temporal gyrus (STG) and bilateral anterior cingulate gyrus (ACG). They localized after SCS, but remained. (2)In the GR group, increased rCBF areas were noted in bilateral precuneus and bilateral cerebellum under the baseline condition. After SCS, they localized in bilateral precuneus but those of bilateral cerebellum remained. Decreased rCBF area was noted in bilateral subcallosal gyrus, STG and bilateral ACG under the baseline. After SCS, they localized in bilateral subcallosal gyrus and bilateral STG. In contrast, they enlarged in bilateral ACG.ConclusionChronic pain patients demonstrated abnormal rCBF distribution on both baseline and post SCS conditions. Increased rCBF of thalamus and precuneus under both conditions in the PR group and decreased rCBF of ACG under post SCS conditions in the GR group were characteristic patterns. Tc-99m-HMPAO SPECT with 3D-SSP and SEE analysis is likely objective and effective in monitoring and evaluating therapeutic outcome by SCS in chronic pain. In addition, it provides information that is useful in the selection of SCS candidates.

Usefulness of a deep-inspiration breath-hold 18F-FDG PET/CT technique in diagnosing liver, bile duct, and pancreas tumors.

BackgroundThe deep-inspiration breath-hold 18F-fluorodeoxyglucose PET/computed tomography (DIBH 18F-FDG PET/CT) technique improves the limitations of diagnosing a lesion located in an area influenced by respiratory motion that brings about spatial misregistration caused by respiration between PET and CT. However, its clinical effectiveness with regard to abdominal lesions has not been elucidated. The influence of respiratory motion for calculating the maximal standardized uptake value (SUVmax) and metabolic volume (MV) in DIBH 18F-FDG PET/CT has not been investigated either. ObjectiveThe purpose of this study was to investigate the usefulness of the DIBH 18F-FDG PET/CT technique in diagnosing liver tumors, bile duct cancers, and pancreas tumors. In addition, we compared the values of SUVmax and MV between DIBH and nonbreath-hold (NBH). MethodsForty patients with various abdominal malignancies including liver tumors, bile duct cancers, and pancreas tumors were enrolled. In total, the patients had 47 abdominal lesions. All patients showed a misregistered image in the early whole-body image taken 50 min after intravenous 18F-FDG infusions. We added the delayed images 40 min after the first image. On the delayed image, we carried out both conventional techniques with normal respiration (NBH) and the DIBH technique. Finally, we compared two kinds of images in each patient. At the same time, we compared both SUVmax and MV of cancer obtained by the two kinds of imaging methods. ResultsIn 14 lesions (29.8%), we corrected the anatomical tumor location, from the incorrect to the correct organ, by the DIBH technique. In 22 lesions (46.8%), we corrected the tumor location within the organ. Consequently, tumor staging also changed in 11 patients (23.4%) after correction by the DIBH technique. Regarding the SUVmax value by DIBH, it showed an increase of approximately 15.0–58.6% compared with that measured by NBH. In contrast, the value of MV by DIBH showed a decrease of 20% compared with that measured by NBH. ConclusionThe DIBH 18F-FDG PET/CT technique is feasible for accurate localization when diagnosing of liver tumors, bile duct cancers, and pancreas cancers. The DIBH technique also improves the inaccurate quantification of both SUVmax and MV.

Comparison of diagnostic and prognostic capabilities of 18F-FDG-PET/CT, 131I-scintigraphy, and diffusion-weighted magnetic resonance imaging for postoperative thyroid cancer

PurposeThe first aim of this study was to compare the detectability of metastasis of postoperative differentiated thyroid cancer (DTC) among 131I whole body scintigraphy (IWBS), fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), and diffusion-weighted magnetic resonance imaging (DWI). The second aim was to clarify the association between the image pattern and prognosis.Materials and methodsWe evaluated 70 postoperative DTC patients on both a patient basis and an organ basis (lymph nodes, lung, bone), and we analyzed the correlation between the image pattern and the prognosis.ResultsFor the patient-basis analysis, the detectability by IWBS, PET/CT, and DWI was 67.1%, 84.2%, and 57.6%, respectively. IWBS provided complementary information to that provided by PET/CT in 11 of 70 (15.7%) cases. For the organ-basis analysis, IWBS was the best detector for lymph node metastasis (72.4%). PET/CT was superior to IWBS for detecting metastasis of bone (85.7% vs. 71.4%) and lung (94.1% vs. 62.7%). For the correlation analysis, PET and DWI positivity were the factors predicting a poor prognosis.ConclusionPET/CT was the best modality for detecting metastases in postoperative DTC patients, although IWBS provided complementary information. Because PET/CT and DWI gave similar information (e.g., positivity) suggesting poor prognoses, the combination of IWBS and DWI might be the method of choice for monitoring postoperative DTC.

Assessment of diastolic function using 16-frame 201Tl gated myocardial perfusion SPECT: a comparative study of QGS2 and pFAST2

ObjectiveThe objective of the present study is to investigate the correlations across various types of interface software for 201Tl gated myocardial perfusion SPECT (MPS) in calculating two common diastolic function parameters (DFx), peak-filling rates (PFR), and time-to-peak filling (TTPF).MethodsA total of 109 patients (66 men and 43 women; age 35–78 years) were studied. All patients were classi-fied into three groups (i.e., ND, no-defect group; SD, small-defect group; LD, large-defect group) to clarify the influence of perfusion defects possibly affecting the analysis. Two kinds of available software, namely, quantitative gated SPECT (QGS2) and perfusion and functional analysis for gated SPECT (pFAST2) with cardioGRAF were used to obtain PFR and TTPF. Finally, we analyzed the correlation between DFx obtained with the two different kinds of software.ResultsThe values of LVEF, PFR, and TTPF were assessed in all patients. In both the ND (correlation coefficients were 0.92, 0.79, and 0.99, respectively) and SD groups (correlation coefficients were 0.74, 0.88, and 0.98, respectively), a strong correlation was observed. In contrast, PFR did not show a significant correlation in the LD group.ConclusionsWith the two different kinds of software, QGS2 and pFAST2, the calculated PFR was almost equal and showed good correlations in both ND and SD groups. In contrast, the numerical value varied between the two methods, and its correlation was poor in the LD group. However, TTPF showed a good correlation regardless of the presence of perfusion defects, and the values were equal. TTPF was confirmed to be a stable diastolic index across the two kinds of software, QGS2 and pFAST2, in 201Tl gated MPS.

Effect of percutaneous endoscopic gastrostomy on gastrointestinal motility: evaluation by gastric-emptying scintigraphy.

PurposeFirstly, to assess the effect of percutaneous endoscopic gastrostomy (PEG) tube placement on gastric emptying, gastrointestinal (GI) tract motility and the rate of gastroesophageal reflux (GER). Secondly, to confirm whether correlations exist between drug absorption behaviour and GI tract motility using the combination method of absorption function analysis with the motility study. MethodsSubjects comprised 11 patients with neurological dysphagia. Gastric-emptying scintigraphy was performed both before PEG via nasogastric tube feeding and after PEG placement. After fasting for more than 8 h, each patient was administered 111 MBq of 99mTc-labelled diethylenetriaminepentaacetic acid (DTPA) with a 100 ml liquid meal via a nutrition tube. Dynamic imaging was performed immediately after administration of a radiolabelled liquid meal for a 1 h period and static imaging was performed after 1, 2, 3 and 6 h. Gastric emptying half-time (T50) was calculated in each patient, and GER ratio and GI transit rate were also evaluated. Simultaneously, we administered 10 mg of famotidine in six of the 11 patients and measured serum concentrations of famotidine at 0, 1, 2, 3 and 6 h. Using the time–concentration curve of famotidine, the maximum concentration of famotidine (Cmax) and area under the curve of famotidine (AUCf) were calculated for each patient. ResultsIn seven of 11 patients, T50 changed after PEG placement, but not significantly. The GER ratio was significantly decreased and complicated pneumonia improved after PEG placement. GI transit rate for each GI segment was unchanged after PEG placement. Significant linear correlations were identified between T50 and both Cmax and AUCf. ConclusionGastric-emptying scintigraphy with 99mTc-DTPA was effective in the evaluation of GI transit before and after PEG, as well as in assessing GER. Motility and famotidine absorption were maintained after PEG placement. Significant linear correlations were found between T50 and both Cmax and AUCf. These findings suggest that drug absorption may have some relationship between T50. The result may be more reliable with a larger population.

Relationship between cancer cell proliferation, tumour angiogenesis and 201Tl uptake in non-small cell lung cancer.

Purpose To investigate whether 201Tl uptake is associated with cell proliferation and angiogenesis in non-small-cell lung carcinoma (NSCLC). Methods Eighty-four patients with scheduled NSCLC underwent 201Tl single photon emission computed tomography (SPECT) imaging: 15 min (early scan) and 240 min (delayed scan) after intravenous injection of 111 MBq of 201Tl chloride. 201Tl indices were calculated on early images (early ratio: ER) and delayed images (delayed ratio: DR). The retention index (RI) was also calculated from these two parameters. Using surgically resected cancer specimens (54 adenocarcinoma, 24 squamous cell carcinoma (SCC), six large-cell carcinoma), immunohistochemical stains for both Ki-67 (MIB-1 index) and CD34 were performed to examine the proliferative activity and the micro-vessel density (MVD), respectively. Results The mean value of 201Tl index was 1.69±0.77 (ER) and 2.31±1.08 (DR). The average RI was 42.6±42.9%, respectively. Both DR and RI positively correlated with MIB-1 index (r=0.68, P<0.05 and r=0.52, P<0.05). When we analyse adenocarcinoma and SCC separately, there was a significant positive correlation (r=0.62, P<0.05) between RI and MIB-1 index in adenocarcinoma but not in SCC (r=0.20, P=NS). The value of ER positively correlated with MVD (r=0.75, P<0.05). It demonstrated strong positive correlation with both histological types (adenocarcinoma: r=0.80, P<0.05, SCC: r=0.66, P<0.05). Conclusion 201Tl SPECT imaging is effective non-invasive method for assessing both the proliferation and the angiogenesis in NSCLC. Both DR and RI are useful indicators for assessing cancer cell proliferation in lung adenocarcinoma. ER is a useful marker for assessing the tumour angiogenesis in NSCLC.

Usefulness of triple-phase thallium-201 SPECT in non-small-cell lung cancer (NSCLC): association with proliferative activity.

ObjectiveThe conventional delayed scan in dual phase of thallium-201 (201Tl) single-photon emission computed tomography (SPECT) is useful for estimating the viability of non-small-cell lung cancer (NSCLC). However, the influence of tumor blood flow cannot be ignored by the scan at 4 h after the tracer injection. For the purpose of improving the diagnostic capability and for clarifying the association between 201Tl uptake and proliferative activity, we investigated the usefulness of super-delayed scan obtained at 24 h in triple-phase 201Tl SPECT.MethodsA total of 122 patients with lung nodule, 106 of NSCLC and 16 of benign nodule, were given 201Tl SPECT before the tumor resection. Early image (15 min), delayed image (4 h), and super-delayed image (24 h) were obtained after intravenous injection of 201Tl chloride (111 MBq). On the each SPECT image, regions of interest (ROIs) were placed over the tumor contour (T) and contra-lateral normal lung tissue (N) area on one transverse view clearly defined lesions, and T/N ratio on the early image (ER), the delayed image (DR), and the super-delayed image (sDR), and retention indexes (RI and sRI) were calculated. All patients underwent subsequent surgical excision, and the specimens were immunostained for Ki-67 and CD34. The proliferative capability was measured as a percentage of positive nuclear area for Ki-67 (MIB-1 index). The angiogenesis was measured density of positive micro-vessels for CD34 (micro-vessel density, MVD). Correlation analysis was performed to evaluate the relationship between the MIB-1 index, MVD, and SPECT parameters.ResultsThe diagnostic accuracy of sDR in the differential of NSCLC was higher than that of DR (83.6% vs. 91.8%). Both DR and sDR were positively correlated with MIB-1 index. The correlation coefficient was higher in sDR (0.53 vs. 0.69). The MIB-1 index of the increasing pattern (RI < sRI) group was significantly higher (P < 0.001) than that of the decreasing pattern (RI > sRI) group.ConclusionsThe super-delayed scan in the triple-phase 201Tl SPECT is more useful than conventional delayed scan for both the diagnostic capability and assessing proliferation of NSCLC.