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Objective: This study aimed to quantitatively evaluate the effects of age, mammographic density, menopausal status, and menstrual cycle on background parenchymal uptake (BPU) using ring-shaped dedicated breast positron emission tomography (dbPET). Methods: This study included 186 adult women who underwent mammography and dbPET on the same day and had no abnormalities classified as Breast Imaging Reporting and Data System (BI-RADS) category 1 on both examinations. The volume of interest (VOI) was placed in the glandular tissue of both breasts, and the maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), and metabolic breast volume (MBV) were measured as indicators of BPU. We analyzed the correlation between BPU and age, mammographic density, menopausal status, and menstrual cycle. Results: The SUVmax and SUVmean for normal breast tissue were inversely correlated with age (both p

Aims Coronary microvascular dysfunction (CMD) is related to the pathophysiology, mortality, and morbidity of heart failure with preserved ejection fraction (HFpEF). A novel single-photon emission computed tomography (SPECT) camera with cadmium zinc telluride (CZT) detectors allows for the quantification of absolute myocardial blood flow and myocardial flow reserve (MFR) in patients with coronary artery disease. However, the potential of CZT-SPECT assessing for CMD has never been evaluated in patients with HFpEF. Methods and results The clinical records of 127 consecutive patients who underwent dynamic CZT-SPECT were retrospectively reviewed. Rest and stress scanning were started simultaneously with 3 and 9 MBq/kg of 99mTc-sestamibi administration, respectively. Dynamic CZT-SPECT imaging data were analysed using a net-retention model with commercially available software. Transthoracic echocardiography was performed in all patients. The MFR value was significantly lower in the HFpEF group (mean ± SEM = 2.00 ± 0.097) than that in the non-HFpEF group (mean ± SEM = 2.74 ± 0.14, P = 0.0004). A receiver operating characteristic analysis indicated that if a cut-off value of 2.525 was applied, MFR could efficiently distinguish HFpEF from non-HFpEF. Heart failure with preserved ejection fraction had a consistently low MFR, regardless of the diastolic dysfunction score. Heart failure with preserved ejection fraction patients with MFR values lower than 2.075 had a significantly higher incidence of heart failure exacerbation. Conclusion Myocardial flow reserve assessed by CZT-SPECT was significantly reduced in patients with HFpEF. A lower MFR was associated with a higher hospitalization rate in these patients. Myocardial flow reserve assessed by CZT-SPECT has the potential to predict future adverse events and stratify the severity of disease in patients with HFpEF.

Individuals with prodromal symptoms of Lewy body disease (LBD), such as rapid eye movement sleep behavior disorder (RBD), often showed imaging defects similar to patients. We examined dopamine transporter (DaT) single-photon-emission computed tomography (SPECT) and metaiodobenzylguanidine (MIBG) scintigraphy in 69 high-risk subjects with ≥ 2 prodromal symptoms (dysautonomia, hyposmia, and RBD) and 32 low-risk subjects without prodromal symptoms, whom were identified through a questionnaire survey of health checkup examinees. The high-risk subjects had significantly worse scores on Stroop test, line orientation test, and the Odor Stick Identification Test for Japanese than the low-risk subjects. The prevalence of abnormalities on DaT-SPECT was higher in the high-risk group than in the low-risk group (24.6% vs. 6.3%, p = 0.030). A decreased uptake on DaT-SPECT was associated with motor impairment, and MIBG scintigraphy defects were associated with hyposmia. The simultaneous evaluation of DaT-SPECT and MIBG scintigraphy may capture a wide range of individuals with prodromal LBD.

This study aimed to analyze whether the development of donor vessels after combined revascularization surgery for moyamoya disease (MMD) was related to cerebral blood flow (CBF) changes. We retrospectively reviewed the charts of 11 adult (12 hemispheres) and 13 pediatric (19 hemispheres) patients who underwent combined revascularization in our department. The total vessel cross-sectional area (TVA) was the sum of the cross-sectional areas of the superficial temporal, middle meningeal, and deep temporal arteries imaged using time-of-flight magnetic resonance angiography. The ipsilateral relative CBF (RCBF) on the brain surface in the craniotomy area was calculated by single-photon emission computed tomography. The preoperative and postoperative ratios of the TVA and RCBF were defined as ΔTVA and ΔRCBF, respectively. Finally, we investigated the correlation between ΔTVA and ΔRCBF in adults and children. The TVA and RCBF showed a significant increase after surgery regardless of the age group. However, there was no significant correlation between ΔTVA and ΔRCBF in either the adult or pediatric groups. The adult group had significantly higher ΔRCBF values than the pediatric group (p

Accurate tracer accumulation evaluation is difficult owing to the partial volume effect (PVE). We proposed a novel semi-quantitative approach for measuring the accumulation amount by examining the approximate image. Using a striatal phantom, we verified the validity of a newly proposed method to accurately evaluate the tracer accumulations in the caudate and putamen separately. Moreover, we compared the proposed method with the conventional methods.The left and right caudate/putamen regions and the whole brain region as background were identified in computed tomography (CT) images obtained by single-photon emission computed tomography (SPECT)/CT and acquired the positional information of each region. SPECT-like images were generated by assigning assumed accumulation amounts to each region. The SPECT-like image, approximated to the actual measured SPECT image, was examined by changing the assumed accumulation amounts assigned to each region. When the generated SPECT-like image most approximated the actual measured SPECT image, the accumulation amounts assumed were determined as the accumulation amounts in each region. We evaluated the correlation between the count density calculated by the proposed method and the actual count density of theThe correlation coefficients between the actual count density and the SPECT count densities were 0.997, 0.973, 0.951, 0.950, and 0.996 for the proposed method, CT-guide method, GTM method, RBV method, and Southampton method, respectively. The correlation of the proposed method was significantly higher than those of the other methods.The proposed method could calculate accurate accumulation amounts in the caudate and putamen separately, considering the PVE.

BACKGROUND Symptomatic hyperperfusion after cerebral revascularization for pediatric moyamoya disease (MMD) is a rare phenomenon. The authors report a series of patients with this condition. OBSERVATIONS In all three patients in this case series, the combined revascularization was on the left side, the patency of bypass grafts was confirmed after surgery, and focal hyperemia around the anastomotic site was observed on single photon emission computed tomography (SPECT). On the first to eighth days after surgery, all of the patients developed neurological manifestations, including motor aphasia, cheiro-oral syndrome, motor weakness of their right upper limbs, and severe headaches. These symptoms disappeared completely approximately 2 weeks after surgery, and all patients were discharged from the hospital. Quantitative SPECT was performed to determine the proportional change in cerebral blood flow (ΔRCBF) (to ipsilateral cerebellar ratio (denoted ΔRCBF) in the region of interest around the anastomoses, and the mean value was 1.34 (range, 1.29–1.41). LESSONS This rare condition, which develops soon after surgery, requires an accurate diagnosis by SPECT. One indicator is that the ΔRCBF has risen to 1.3 or higher. Subsequently, strategic blood pressure treatment and fluid management could prevent the development of hemorrhagic stroke.

Background This study examined the variation in the thyroid volume determined by the ellipsoid approximation method due to differences in the measured length or area of the cross-sectional plane of CT images. Methods Forty-five patients with Graves' diseasewere included in this retrospective study. We designated the three-dimensional thyroid volumes extracted manually (VCT) as the reference data and calculated five approximate volumes for comparison: (1) the mean volume of 8100 different thyroid volumes depending on the diameter of the cross-sectional plane at the midpoint of the major axis, (Vellipsoid,mean); (2) the volume using the maximum diameter and its orthogonal diameter, (Vellipsoid,maxlength); (3) the maximum (Vellipsoid,maxvolume) and (4) minimum (Vellipsoid,minvolume) of the 8100 thyroid volumes; and (5) the volume determined with an equivalent circle diameter, (Vellipsoid,Heywood). Results Thyroid volumes obtained via the ellipsoid approximation method varied depending on the diameter of the cross-sectional plane and included a mean error of approximately 20%, while the concordance correlation coefficient (CCC) differed for each approximate volume. Among these volumes, Vellipsoid,meanand Vellipsoid,Heywoodwere in good agreement with VCT, according to single regression analyses and the resultant CCC values, with mean errors of 7.0% and 2.5%, respectively. Conclusion WhileVellipsoid,Heywoodapproximated thyroid volumes with vastly reduced errors, we recommend utilizing three-dimensional thyroid volumetry if measurement accuracy is required.

Breast positron emission tomography (PET) has had insurance coverage when performed with conventional whole-body PET in Japan since 2013. Together with whole-body PET, accurate examination of breast cancer and diagnosis of metastatic disease are possible, and are expected to contribute significantly to its treatment planning. To facilitate a safer, smoother, and more appropriate examination, the Japanese Society of Nuclear Medicine published the first edition of practice guidelines for high-resolution breast PET in 2013. Subsequently, new types of breast PET have been developed and their clinical usefulness clarified. Therefore, the guidelines for breast PET were revised in 2019. This article updates readers as to what is new in the second edition. This edition supports two different types of breast PET depending on the placement of the detector: the opposite-type (positron emission mammography; PEM) and the ring-shaped type (dedicated breast PET; dbPET), providing an overview of these scanners and appropriate imaging methods, their clinical applications, and future prospects. The name “dedicated breast PET” from the first edition is widely used to refer to ring-shaped type breast PET. In this edition, “breast PET” has been defined as a term that refers to both opposite- and ring-shaped devices. Up-to-date breast PET practice guidelines would help provide useful information for evidence-based breast imaging.

Purpose To establish an objective method of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) that can assist in the diagnosis of glucose transporter 1 deficiency syndrome (GLUT1-DS). Methods FDG-PET was performed in 8 patients with a mean age of 12.5 years (range, 2–22 years) with GLUT1-DS. Their PET findings were compared with those of 45 controls with a mean age of 11.2 years (range, 2–21 years) by statistical parametric mapping (SPM12, Welcome Neurological Institute). The controls had epilepsy of unknown etiology and normal MRI findings. The age-adjusted ratios of mean radioactivities in regions of interest (ROIs) of bilateral lenticular nuclei, thalami, and the whole cerebral cortex were also measured. The sensitivities and specificities of the ratios for the differential diagnosis of GLUT1-DS were also determined. Results SPM showed significantly decreased uptake in bilateral thalami and increased uptake in bilateral lenticular nuclei in patients with GLUT1-DS. There were no areas in the cerebral cortex with significant differences between patients and controls. On ROI analysis, by setting the cut-off value of the age-adjusted lenticular nuclei/thalami radioactivity ratio to 1.54, patients with GLUT1-DS were differentiated from controls with sensitivity of 1.00 and specificity of 0.98. Conclusion The age-adjusted lenticular nuclei/thalami radioactivity ratio on PET can distinguish patients with GLUT1-DS from patients with epilepsy of unknown etiology with high sensitivity and specificity. It is important to pay attention to the metabolism of the lenticular nuclei and thalami on PET for the diagnosis of GLUT1-DS.

Objective The objective of this study was to assess the correlation between dual-energy computed tomography quantitative parameters and hemodynamics in patients with chronic thromboembolic pulmonary hypertension. Methods Dual-energy computed tomography of 52 chronic thromboembolic pulmonary hypertension patients were evaluated retrospectively. The mean lung perfused blood volume (lung PBV) and the mean pulmonary artery (PA) enhancement measured at pulmonary parenchymal phase were compared with the hemodynamics by Spearman rank correlation coefficient (rs) and receiver operating characteristic analysis. Results Lung PBV was correlated with mean pulmonary arterial pressure (rs = 0.47, P < 0.001). Pulmonary artery enhancement was correlated with cardiac index (rs = −0.49, P < 0.001) and pulmonary vascular resistance (rs = 0.48, P < 0.001). The areas under the curves were 0.86 for lung PBV to predict mean pulmonary arterial pressure of >50 mm Hg and 0.86 for PA enhancement to predict pulmonary vascular resistance of >1000 dyne·s/cm5. Conclusions Lung PBV and PA enhancement could be indicators of hemodynamics.

The purpose of this study was to examine the effects of combined revascularization for ischaemic-onset moyamoya disease (MMD) on cerebral haemodynamics by comparing cerebral blood flow (CBF) during the postoperative chronic phase with preoperative CBF. A retrospective cohort of 24 MMD patients (representing 31 surgeries) who received single photon emission computed tomography (SPECT) before and more than 6 months after surgery was investigated. The CBF value of each vascular territory was extracted from SPECT data, and the value relative to the ipsilateral cerebellar value (relative CBF, or RCBF) was calculated. The correlation between the revascularization effect and the proportional change in RCBF before and after surgery (calculated as post-RCBF/pre-RCBF ("post/pre-RCBF")) was analysed. Furthermore, the relationships between changes in neurological symptoms and post/pre-RCBF were investigated. Preoperative and postoperative mean RCBF values were 0.92 ± 0.15 and 0.96 ± 0.13 (p = 0.619) in the anterior cerebral artery territory, 0.99 ± 0.17 and 1.01 ± 0.17 (p = 0.598) in the middle cerebral artery territory and 1.15 ± 0.22 and 1.14 ± 0.19 (p = 0.062) in the posterior cerebral artery territory, respectively. No significant correlation was found between the revascularization score and post/pre-RCBF. The revascularization score and post/pre-RCBF were not significant predictors of worsening neurological symptoms postoperatively. No significant change in RCBF was observed in any vascular territory in the chronic phase after revascularization. Combined revascularization may assist in the redirection of blood flow from the internal to the external carotid system and contribute to CBF maintenance.

Internal radiation therapy using 3-iodobenzylguanidine (

Internal radiation therapy using lutetium-177(

PURPOSE This paper aims to explore the role of a metabolic parameter on F-FDG-PET/CT for clinical T-classification in early-stage adenocarcinoma. PATIENTS AND METHODS One hundred six surgically resected pathological TNM stage (p-stage) 0/I lung adenocarcinomas were retrospectively reviewed. The solid size (SS) measured on thin-section CT and the pathological invasive size (IS) of tumors were recorded. The SUVmax and metabolic tumor volume with SUV ≥1.0 (MTV1.0) derived from PET/CT data were measured on a workstation, and the metabolic tumor diameter with SUV ≥1.0 (MTD1.0) was calculated automatically from MTV1.0. For the correlations between the IS and the SS, MTD1.0, or SUVmax, Pearson's correlation coefficients were compared using the Meng-Rosenthal-Rubin method. Additionally, the reproducibility between the clinical TNM stage (c-stage), based on the SS or MTD1.0, and the p-stage was analyzed using the kappa coefficient (k). RESULTS For the correlations between the IS and the other parameters, Pearson correlation coefficient was 0.630 for the SS, 0.600 for the SUVmax, and 0.725 for MTD1.0. MTD1.0 correlated significantly and more strongly with the IS than the SS and the SUVmax did (P = 0.040, and P = 0.008, respectively). The reproducibility between p-stage and c-stage based on the SS was moderate (k = 0.529, P < 0.001), whereas that between p-stage and c-stage based on MTD1.0 was substantial (k = 0.676, P < 0.001). CONCLUSIONS MTD1.0 on FDG-PET/CT was correlated significantly and more strongly with the pathological IS in lung adenocarcinomas than with the SS on thin-section CT. FDG-PET/CT could classify more precisely early-stage lung adenocarcinoma than the presently used T-classification based on thin-section CT findings.

BackgroundSemi-quantitative analysis is used to evaluate the degree of tracer binding to the striatum in dopamine transporter (DaT) single-photon emission computed tomography (SPECT). In DaT SPECT, it is difficult to evaluate the accurate tracer accumulation due to the partial volume effect (PVE). In this study, we propose a novel semi-quantitative approach for measuring the amount of accumulation by examining the approximate image. Using the striatal phantom, we verified the validity of a newly proposed method that can accurately evaluate the tracer accumulations in the caudate and putamen, separately.MethodsThe left and right caudate/putamen regions, and the whole brain region as the background (BG) region were identified in computed tomography (CT) images obtained by SPECT/CT imaging, and the positional information of each region was obtained. The SPECT-like images were generated by assigning assumed accumulation amounts to the left and right caudate/putamen and BG regions based on the positional information. By changing the assumed accumulation amounts assigned to each region, the SPECT-like image, which was approximated to the image obtained by the SPECT imaging, was examined. The accumulation amounts assumed, when the generated SPECT-like image approximated the most to the image actually obtained by the SPECT imaging, were determined as the accumulation amounts in each region. We evaluated the correlation between the count density calculated by the proposed method and the actual count density of 123I solution filled into the striatal phantom, and verified the validity of the proposed method. In addition, the specific binding ratio (SBR) and caudate-putamen ratio (CPR) computed by the proposed method were compared with the theoretical SBR and CPR calculated by the count density of the 123I solution filled into the striatal phantom.ResultsThe count density calculated by the proposed method and the count density of 123I solution filled in the striatal phantom had an extremely strong positive correlation (r=0.997, p < 0.001). The SBRs computed by the proposed method were overestimated. However, the obtained CPRs were very similar to the theoretical CPRs.ConclusionsThe proposed method was able to compute the accurate accumulation amounts in the caudate and putamen, considering the PVE.

Background The heritability of Type 2 diabetes mellitus (T2DM) has been estimated to be 50% to 60%. Although genome-wide association studies identified >120 loci that confer susceptibility to T2DM, these studies were commonly conducted in a cross-sectional manner. Purpose The purpose of the study was to identify genetic variants that confer susceptibility to T2DM in Japanese. We have now performed longitudinal exome-wide association studies (EWASs) to identify novel loci for T2DM by examining temporal changes in fasting plasma glucose (FPG) level, blood hemoglobin A1c (HbA1c) content, and the prevalence of T2DM. Methods Longitudinal EWASs (mean follow-up period, 5 years) were performed with Illumina Human Exome-12 v1.2 DNA Analysis BeadChip or Infinium Exome-24 v1.0 BeadChip arrays and with 6,022 Japanese (755 subjects with T2DM, 5267 controls). The relation of genotypes of 24,579 SNPs that passed quality control to FPG level, blood HbA1c content, or the prevalence of T2DM was examined with the generalized estimating equation (GEE). To compensate for multiple comparisons of genotypes with each of the three parameters, we applied Bonferroni's correction for statistical significance of association. Results Longitudinal EWASs (GEE with adjustment for age, sex, body mass index, and smoking) revealed that rs6414624 of EVC (P Conclusion We have newly identified EVC and GGA3 as susceptibility loci for T2DM in Japanese. Determination of genotypes for these SNPs at these loci may prove informative for assessment of the genetic risk for T2DM in Japanese. Funding Acknowledgement Type of funding source: None

Written by associate editors of the Annals of Nuclear Medicine, this invited review article is intended to offer our readers a condensed global view on the high-quality research work that has been published in Europe last year. We have divided this article into five sections. The first three sections from the oncology category include “[18F]fluorodeoxyglucose (FDG) positron-emission tomography (PET) for therapy monitoring in malignant lymphoma”, “[18F]fluoromisonidazole (FMISO) PET for hypoxia”, and “lymphoscintigraphy update”. It is followed by a section on “amyloid PET for Alzheimer’s disease” using [11C]Pittsburgh Compound B (PiB) and [18F]florbetapir from the neurology category. The final section reviews three original articles in the field of “basic and translational molecular imaging” regardless of the category, which investigated new PET tracers such as L-4-borono-2-[18F]fluoro-phenylalanine (FBPA), O-(2-[18F]fluoroethyl)-L-tyrosine (FET) and 64Cu-NOTA-pertuzumab in small animals. We hope that this review article will arouse greater interest in our readers in recent European research trends in the field of nuclear medicine.

Background The circulating concentrations of triglycerides, high density lipoprotein (HDL)–cholesterol, and low density lipoprotein (LDL)–cholesterol have a substantial genetic component, and the heritability of early-onset dyslipidemia is expected to be higher than that of late-onset forms of this condition. Purpose To identify genetic variants that confer susceptibility to early-onset hypertriglyceridemia, hypo–HDL-cholesterolemia, and hyper–LDL-cholesterolemia in Japanese. We have now performed exome-wide association studies (EWASs) for early-onset forms of these conditions. Methods A total of 8073 individuals aged ≤65 years was enrolled in the study. The EWASs for hypertriglyceridemia (2664 cases, 5294 controls), hypo–HDL-cholesterolemia (974 cases, 7085 controls), and hyper–LDL-cholesterolemia (2911 cases, 5111 controls) were performed with Illumina Human Exome-12 v1.2 DNA Analysis BeadChip or Infinium Exome-24 v1.0 BeadChip arrays. The relation of allele frequencies for 31,198, 31,133, or 31,175 single nucleotide polymorphisms (SNPs) that passed quality control to hypertriglyceridemia, hypo–HDL-cholesterolemia, or hyper–LDL-cholesterolemia, respectively, was examined with Fisher's exact test. To compensate for multiple comparisons of genotypes with each of the three conditions, we applied Bonferroni's correction for statistical significance of association. Results The EWASs of allele frequencies revealed that 25, 28, or 65 SNPs were significantly associated with hypertriglyceridemia (P Conclusion We have thus identified 12 novel loci that confer susceptibility to early-onset dyslipidemia. Determination of genotypes for the SNPs at these loci may prove informative for assessment of the genetic risk for hypertriglyceridemia, hypo–HDL-cholesterolemia, or hyper–LDL-cholesterolemia in Japanese.

Background Given that early-onset type 2 diabetes mellitus (T2DM), metabolic syndrome, and hyperuricemia have been shown to have strong genetic components, statistical power of a genetic association study may be increased by focusing on early-onset subjects with these conditions. Although genome-wide association studies have identified various genes and loci significantly associated with T2DM, metabolic syndrome, and hyperuricemia, genetic variants that contribute to predisposition to these conditions in Japanese individuals remain to be identified definitively. Purpose The purpose of the study was to identify genetic variants that confer susceptibility to early-onset T2DM, metabolic syndrome, or hyperuricemia in Japanese. We have now performed exome-wide association studies (EWASs) for early-onset subjects with T2DM, metabolic syndrome, or hyperuricemia and corresponding controls. Methods A total of 8102 individuals aged ≤65 years was enrolled in the study. The EWAS for T2DM was performed with 7407 subjects (1696 cases, 5711 controls), that for metabolic syndrome with 4215 subjects (2296 cases, 1919 controls), and that for hyperuricemia with 7919 subjects (1365 cases, 6554 controls). Single nucleotide polymorphisms (SNPs) were genotyped with Illumina Human Exome-12 DNA Analysis BeadChip or Infinium Exome-24 BeadChip arrays. The relation of allele frequencies for 31,210, 31,521, or 31,142 SNPs that passed quality control to T2DM, metabolic syndrome, or hyperuricemia, respectively, was examined with Fisher's exact test. To compensate for multiple comparisons of genotypes with T2DM, metabolic syndrome, or hyperuricemia, we applied Bonferroni's correction for statistical significance of association. Results The EWAS of allele frequencies revealed that four, six, or nine SNPs were significantly associated with T2DM (P Conclusion Given that OR4F6 was significantly associated with both T2DM and metabolic syndrome, we thus newly identified four genes (ZNF860, OR4F6, OR52E4, HERPUD2) that confer susceptibility to early-onset T2DM, metabolic syndrome, or hyperuricemia. Determination of genotypes for the SNPs in these genes may prove informative for assessment of the genetic risk for T2DM, metabolic syndrome, or hyperuricemia in Japanese.

Background Before radioiodine therapy for Graves’ disease, the estimated thyroid-absorbed dose is calculated based on various clinical parameters. However, the actual accumulation of iodine in the thyroid during radioiodine therapy is not determined. We validated the feasibility of post-therapeutic image-based thyroid dosimetry through quantitative single-photon emission computed tomography (SPECT) imaging and thyroid biokinetics and expanding the Medical Internal Radiation Dose Committee’s (MIRD) voxel dosimetry guidelines. Methods Forty-three patients with Graves’ disease who underwent radioiodine therapy were chosen as subjects for this retrospective analysis. We acquired patients’ SPECT images 24 h after oral administration. SPECT images were quantified using system volume sensitivity to calculate time-integrated activity coefficients on a voxel basis. Absorbed dose was obtained by convolving MIRD guideline voxel S values with time-integrated activity coefficients. To determine accuracy, we compared the results obtained using the post-therapeutic image-based absorbed-dose method (D̅image,PVC) with absorbed doses calculated using the method described by the European Association of Nuclear Medicine (pre-therapeutic method; DEANM). Results Using image-based dosimetry as post-therapeutic dosimetry, we visualized the local accumulation and absorbed dose distribution of iodine in the thyroid. Furthermore, we determined a strong correlation (Pearson’s correlation coefficient = 0.89) between both dosimetries, using the regression equation: D̅image,PVC = 0.94 × DEANM + 1.35. Conclusion Post-therapeutic image-based doses absorbed in the thyroid resembled those of pre-therapeutic EANM method-based absorbed doses. Additionally, the post-therapeutic image-based method had the advantage of visualizing thyroid iodine distribution, thus determining local dose distributions at the time of treatment. From these points, we propose that post-therapeutic image-based dosimetry could provide an alternative to standard pre-therapeutic dosimetry to evaluate dose response.

Background Given that substantial genetic components have been shown in ischemic stroke, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH), a heritability may be higher in early-onset than late-onset individuals with these conditions. Although genome-wide association studies have identified various genes and loci significantly associated with ischemic stroke, ICH, or intracranial aneurysm mainly in European ancestry populations, genetic variants that contribute to susceptibility to these disorders in Japanese individuals remain to be identified definitively. Purpose The purpose of the study was to identify genetic variants that confer susceptibility to ischemic stroke, ICH, or SAH in Japanese. We have now performed exome-wide association studies (EWASs) in early-onset subjects with these conditions and corresponding controls. Methods A total of 6649 individuals aged ≤65 years were examined. For the EWAS of ischemic or hemorrhagic stroke, 6224 individuals (450 subjects with ischemic stroke, 5774 controls) or 6179 individuals (261 subjects with ICH, 176 subjects with SAH, 5742 controls), respectively, were examined. EWASs were performed with the use of Illumina Human Exome-12 v1.2 DNA Analysis BeadChip or Infinium Exome-24 v1.0 BeadChip. To compensate for multiple comparisons of allele frequencies with ischemic stroke, ICH, or SAH, we applied a false discovery rate (FDR) of Results The relation of allele frequencies of 31,245 single nucleotide polymorphisms (SNPs) that passed quality control to ischemic stroke was examined with Fisher's exact test, and 31 SNPs were significantly (FDR Conclusion We have thus newly identified nine genes that confer susceptibility to early-onset ischemic stroke, ICH, or SAH. Determination of genotypes for the SNPs in these genes may prove informative for assessment of the genetic risk for ischemic stroke, ICH, or SAH in Japanese.

Background Early-onset coronary artery disease (CAD) has a strong genetic component. Although genome-wide association studies have identified various genes and loci significantly associated with CAD mainly in European ancestry populations, genetic variants that contribute to susceptibility to this condition in Japanese individuals remain to be identified definitively. Purpose The purpose of the study was to identify genetic variants that confer susceptibility to early-onset CAD in Japanese. We have now performed exome-wide association studies (EWASs) in subjects with early-onset CAD and controls. Methods A total of 7256 individuals aged ≤65 years was enrolled in the study. The EWAS was conducted with 1482 subjects with CAD and 5774 controls. Genotyping of single nucleotide polymorphisms (SNPs) was performed with Illumina Human Exome-12 DNA Analysis BeadChip or Infinium Exome-24 BeadChip arrays. The relation of allele frequencies for 31,465 SNPs that passed quality control to CAD was examined with Fisher's exact test. To compensate for multiple comparisons of allele frequencies with CAD, we applied a false discovery rate (FDR) of Results The relation of allele frequencies for 31,465 SNPs to CAD with the use of Fisher's exact test showed that 170 SNPs were significantly (FDR Conclusion We have newly identified 26 loci that confer susceptibility to CAD. Determination of genotypes for the SNPs at these loci may prove informative for assessment of the genetic risk for CAD in Japanese.

Objective Recent many studies have shown that whole body “diffusion-weighted imaging with background body signal suppression” (DWIBS) seems a beneficial tool having higher tumor detection sensitivity without ionizing radiation exposure for pediatric tumors. In this study, we evaluated the diagnostic performance of whole body DWIBS and 18F-FDG PET/CT for detecting lymph node and bone metastases in pediatric patients with neuroblastoma. Methods Subjects in this retrospective study comprised 13 consecutive pediatric patients with neuroblastoma (7 males, 6 females; mean age, 2.9 ± 2.0 years old) who underwent both 18F-FDG PET/CT and whole-body DWIBS. All patients were diagnosed as neuroblastoma on the basis of pathological findings. Eight regions of lymph nodes and 17 segments of skeletons in all patients were evaluated. The images of 123I-MIBG scintigraphy/SPECT-CT, bone scintigraphy/SPECT, and CT were used to confirm the presence of lymph node and bone metastases. Two radiologists trained in nuclear medicine evaluated independently the uptake of lesions in 18F-FDG PET/CT and the signal-intensity of lesions in whole-body DWIBS visually. Interobserver difference was overcome through discussion to reach a consensus. The sensitivities, specificities, and overall accuracies of 18F-FDG PET/CT and whole-body DWIBS were compared using McNemer’s test. Positive predictive values (PPVs) and negative predictive values (NPVs) of both modalities were compared using Fisher’s exact test. Results The total numbers of lymph node regions and bone segments which were confirmed to have metastasis in the total 13 patients were 19 and 75, respectively. The sensitivity, specificity, overall accuracy, PPV, and NPV of 18F-FDG PET/CT for detecting lymph node metastasis from pediatric neuroblastoma were 100, 98.7, 98.9, 95.0, and 100%, respectively, and those for detecting bone metastasis were 90.7, 73.1, 80.3, 70.1, and 91.9%, respectively. In contrast, the sensitivity, specificity, overall accuracy, PPV, and NPV of whole-body DWIBS for detecting bone metastasis from pediatric neuroblastoma were 94.7, 24.0, 53.0, 46.4 and 86.7%, respectively, whereas those for detecting lymph node metastasis were 94.7, 85.3, 87.2, 62.1, and 98.5%, respectively. The low specificity, overall accuracy, and PPV of whole-body DWIBS for detecting bone metastasis were due to a high incidence of false-positive findings (82/108, 75.9%). The specificity, overall accuracy, and PPV of whole-body DWIBS for detecting lymph node metastasis were also significantly lower than those of 18F-FDG PET/CT for detecting lymph node metastasis, although the difference between these 2 modalities was less than that for detecting bone metastasis. Conclusion The specificity, overall accuracy, and PPV of whole-body DWIBS are significantly lower than those of 18F-FDG PET/CT because of a high incidence of false-positive findings particularly for detecting bone metastasis, whereas whole-body DWIBS shows a similar level of sensitivities for detecting lymph node and bone metastases to those of 18F-FDG PET/CT. DWIBS should be carefully used for cancer staging in children because of its high incidence of false-positive findings in skeletons.

In clinical situations, various breast-dedicated positron emission tomography (PET) systems have been used. However, clinical breast-dedicated PET systems have polygonal detector ring. Polygonal detector ring sometimes causes image artifact, so complicated reconstruction algorithm is needed to reduce artifact. Consequently, we developed a circular detector ring for breast-dedicated PET to obtain images without artifact using a simple reconstruction algorithm. We used Lu 1.9 Gd 0.1 SiO5 (LGSO) scintillator block which was made of 1.5 x 1.9 x 15 mm pixels that were arranged in an 8 x 24 matrix. As photodetectors , we used silicon photomultiplier (Si-PM) arrays whose channel size was 3 x 3 mm. A detector unit was composed of four scintillator blocks, 16 Si-PM arrays and a light guide. The developed detector unit had angled configuration since the light guide was bending. A detector unit had three gaps with an angle of 5.625° between scintillator blocks. With these configurations, we could arrange 64 scintillator blocks in nearly circular shape (regular 64-sided polygon) using 16 detector units. The use of the smaller number of detector units could reduce the size of the front–end electronics circuits. The inner diameter of the developed detector ring was 260 mm. This size was similar to those of brain PET systems, so our breast-dedicated PET detector ring can measure not only breast but also brain. Measured radial, tangential and axial spatial resolution of the detector ring reconstructed by the filtered back-projection (FBP) algorithm were 2.1 mm FWHM, 2.0 mm FWHM and 1.7 mm FWHM at center of field of view (FOV), respectively. The sensitivity was 2.0% at center of the axial FOV. With the developed detector ring, we could obtain high resolution image of the breast phantom and the brain phantom. We conclude that our developed Si-PM-based detector ring is promising for a high resolution breast-dedicated PET system that can also be used for brain PET system.

Ra-223 has recently been introduced in alpha-targeting radionuclide therapy. According to the decay scheme of Ra-223, beta particles with higher energy than the Cerenkov-light threshold are emitted. In addition, there are reports that the alpha particles themselves emit luminescence in water and air. However, measured optical imaging results from Ra-223 have not yet been reported. Therefore, we conducted optical imaging of an Ra-223 solution and compared it with that of an F-18 solution. Ra-223 and F-18 solutions contained in transparent glass vials were imaged using a high-sensitivity CCD camera. We could obtain an image of the Ra-223 solution with radioactivity of 0.72 MBq in an acquisition time of less than 10 s. At the same level of radioactivity, the intensity of the optical signal in the solution part of the vial of Ra-223 was 21 times higher than that of F-18. Furthermore, in the air part of the vials, Ra-223 had higher luminescence than that of F-18. The light spectra for Ra-223 and F-18 solutions were similar, but those in the vials' air parts were different. The optical signals in the solution part of both Ra-223 and F-18 are attributed to Cerenkov light, while that in the air part of Ra-223 is attributed to the scintillation of N 2 gas in air. No obvious luminescence of water by the alpha particles was observed. We concluded that optical imaging of the Ra-223 solution was possible, and this solution's light intensity was much higher than that of the F-18 solution and thus easier to detect. Therefore, Ra-223 is a promising radionuclide for optical imaging in distribution measurements.

This study aimed to investigate whether indices of left ventricular (LV) dyssynchrony by gated myocardial perfusion SPECT (GMPS) could be useful to predict prognosis in chronic kidney disease (CKD) patients with normal perfusion defect scores. One hundred and sixty-seven CKD patients with normal perfusion defect scores on adenosine-stress 201Tl GMPS and no previous history of overt heart diseases were enrolled. Phase standard deviation (PSD) and bandwidth (BW) were automatically calculated from GMPS. The major adverse cardiac events (MACEs) for a mean of 560 days were defined as sudden cardiac death, fatal arrhythmias, and acute coronary syndrome requiring urgent coronary revascularization. Patients were divided into two groups according to the presence or absence of MACEs. The MACEs occurred in 12 patients (7.1%). Patients who experienced MACEs showed significantly higher PSD and wider BW than those who did not. In the Kaplan-Meier event-free survival analysis, cardiac event rate was significantly higher in the high-PSD and wide-BW group (n = 81) than in the low-PSD and narrow-BW group (n = 71) (P = .002). The multivariate regression analysis revealed that the PSD was associated with MACEs (odds ratio 1.33, 95% confidence interval 1.05-1.69, P = .01). The LV dyssynchrony indices from GMPS may be novel prognostic predictors in CKD patients with normal perfusion defect scores.

We investigated the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in predicting the effect of induction therapy in patients with thymic epithelial tumors. Fourteen patients with thymic epithelial tumors who underwent PET-CT before and after induction therapy were retrospectively analyzed. The relationship between the change in the maximum standardized uptake value (SUVmax) in PET-CT, the response evaluation criteria in solid tumors and the pathologic response (Ef0, no necrosis of tumor cells; Ef1, some necrosis of tumor cells with more than one-third of viable tumor cells; Ef2, less than one-third of tumor cells were viable; and Ef3, no tumor cells were viable) was analyzed. The study cohort consisted of 5 males and 9 females. Nine of the patients had thymoma, and 5 had thymic carcinoma. The induction therapy included chemotherapy in 9 cases, chemoradiation therapy in 4 cases and radiation therapy in 1 case. Among the 8 patients with a pathologic response of Ef0/1, 5 were clinically evaluated as having stable disease (SD), while 3 were found to have had a partial response (PR). The SUVmax was elevated in 2 cases, unchanged in 1 and decreased in 5. On the other hand, 3 of the 6 patients with a pathologic response of Ef2, 3 were classified as having SD, while the other 3 had a PR. The SUVmax decreased in all of the patients. In comparison with CT, PET-CT seems to be useful for predicting the pathologic response to induction therapy in patients with thymic epithelial tumors.

The prognostic impact and pathophysiology of global left ventricular mechanical dyssynchrony (LVMD), namely mechanical dyssynchrony of whole left ventricle, as assessed by phase analysis of electrocardiographically gated (ECG-gated) myocardial perfusion SPECT has not been clearly elucidated in patients with dilated cardiomyopathy (DCM) and narrow QRS complex (

Ultrahigh resolution small animal PET systems require small pixel size scintillators. We developed an ultrahigh resolution small animal PET system using fine LYSO pixels, which were 0.32 mm×0.5 mm×5.0 mm. The LYSO pixels were combined into a 22×15 matrix with a 0.1 mm thick BaSO 4 reflector between them. The LYSO block was 9.24 mm×9.0 mm×5 mm, and it was optically coupled to a 4×4 through silicon via silicon photomultiplier (TSV Si-PM) array that has smaller gaps between channels with a 1-mm thick light guide. We made eight Si-PM-based block detectors and arranged them octagonally to form a PET detector ring. At the center, the spatial resolution of the developed PET system, which was reconstructed by filtered back projection (FBP), was 0.6-mm FWHM. The sensitivity at the axial center was 0.5%. The peak noise equivalent count rate (NECR) was 12.5 k cps. We obtained high resolution images of phantoms and small animals with the developed PET system. With these results, we conclude that a high resolution PET system is possible with 0.32 mm pixel LYSO scintillators.

We investigated the incidence of cholinergic symptoms related to irinotecan hydrochloride(CPT-11)and examined their association with clinical factors. The subjects were 61 patients with colorectal cancer for whom combination chemotherapy with CPT-11 was indicated between May 2008 and December 2014. The incidence of CPT-11-related cholinergic symptoms was investigated. Cholinergic symptoms were observed in 46 patients(75.4%), of whom 29(47.5%)showed Grade 2 or higher symptoms as follows: nasal discharge(47.5%), lacrimation(39.3%), nausea/vomiting(29.5%), and watery stool (26.2%). The results of the multivariate analysis showed that high-dose CPT-11 administration(150mg/m2)was a significant risk factor for the appearance of cholinergic symptoms and that PS 0 was a significant factor for reducing the onset of symptoms. It is important to adequately manage cholinergic symptoms, considering these clinical factors.

Purpose Positron emission tomography (PET) has high sensitivity for imaging radioactive tracer distributions in subjects. However, it is not possible to image free radical distribution in a subject by PET. Since free radicals are quite reactive, they are related to many diseases, including but not limited to cancer, inflammation, strokes, and heart disease. The Overhauser enhanced magnetic resonance imaging (OMRI) is so far the only method that images free radical distribution in vivo. By combining PET and OMRI, a new hybrid imaging modality might be developed that can simultaneously image the radioactive tracer and free radical distributions. For this purpose, the authors developed a PET/OMRI combined system for small animals. Methods The developed PET/OMRI system used an optical fiber-based PET system combined with a permanent magnet-based OMRI system. The optical fiber-based PET system uses flexible optical fiber bundles. Eight optical fiber-based block detectors were arranged in a 56 mm diameter ring to form a PET system. The LGSO blocks were located inside the field-of-view (FOV) of the OMRI, and the position sensitive photomultiplier tubes were positioned behind the OMRI to minimize the interference between the PET and the OMRI. The OMRI system used a 0.0165 T permanent magnet. The system has an electron spin resonance coil to enhance the MRI signal using the Overhauser effect to image the free radical in the FOV of the PET/OMRI system. Results The spatial resolution and sensitivity of the optical fiber-based PET system were 1.2 mm FWHM and 1.2% at the central FOV, respectively. The OMRI system imaged the distribution of a nitroxyl radical (NXR) solution. The interference between PET and OMRI was small. Simultaneous imaging of the positron radiotracer and the NXR solution was successfully conducted with the developed PET/OMRI system for phantom and small animal studies. Conclusions The authors developed a PET/OMRI combined system with the potential to provide interesting new results in molecular imaging research, such as in vivo molecular and free radical distributions.

Although iodine 131 (I-131) is used for radionuclide therapy, high resolution images are difficult to obtain with conventional gamma cameras because of the high energy of I-131 gamma photons (364 keV). Cerenkov-light imaging is a possible method for beta emitting radionuclides, and I-131 (606 MeV maximum beta energy) is a candidate to obtain high resolution images. We developed a high energy gamma camera system for I-131 radionuclide and combined it with a Cerenkov-light imaging system to form a gamma-photon/Cerenkov-light hybrid imaging system to compare the simultaneously measured images of these two modalities. The high energy gamma imaging detector used 0.85-mm×0.85-mm×10-mm thick GAGG scintillator pixels arranged in a 44×44 matrix with a 0.1-mm thick reflector and optical coupled to a Hamamatsu 2 in. square position sensitive photomultiplier tube (PSPMT: H12700 MOD). The gamma imaging detector was encased in a 2 cm thick tungsten shield, and a pinhole collimator was mounted on its top to form a gamma camera system. The Cerenkov-light imaging system was made of a high sensitivity cooled CCD camera. The Cerenkov-light imaging system was combined with the gamma camera using optical mirrors to image the same area of the subject. With this configuration, we simultaneously imaged the gamma photons and the Cerenkov-light from I-131 in the subjects. The spatial resolution and sensitivity of the gamma camera system for I-131 were respectively ~3 mm FWHM and ~10 cps/MBq for the high sensitivity collimator at 10 cm from the collimator surface. The spatial resolution of the Cerenkov-light imaging system was 0.64 mm FWHM at 10 cm from the system surface. Thyroid phantom and rat images were successfully obtained with the developed gamma-photon/Cerenkov-light hybrid imaging system, allowing direct comparison of these two modalities. Our developed gamma-photon/Cerenkov-light hybrid imaging system will be useful to evaluate the advantages and disadvantages of these two modalities.

It is commonly believed that gamma photon irradiation to water does not produce light in water if the gamma photon energy is lower than the Cerenkov-light threshold and imaging of gamma photon is impossible because the produced electrons from gamma photons do not emit light. However, we found that the light is produced in water and the imaging of produced light in water was possible with gamma photon irradiation even at lower energy than the Cerenkov-light threshold. We irradiated gamma photons with lower energy than the Cerenkov-light threshold (260 keV for electrons in water) from 99mTc (gamma photon energy of 140.5 keV) to water phantom, optical imaging was carried out with a charge-coupled device (CCD) camera. Also we conducted imaging of the gamma photons irradiation to acrylic and plastic scintillator blocks. The optical images of water were observed from 3600 s exposure time, and the intensity of the luminescence was linearly increased with time although the intensity was ~0.001% of that with the plastic scintillator block. The optical imaging of water during irradiation of gamma photons lower energy than the Cerenkov-light threshold was possible and it could be a new method for distribution measurements of gamma photons in water.

Ra-223 has recently been introduced to alpha radionuclide therapy. According to the decay scheme of Ra-223, an inert gas, Rn-219 is released from patients during alpha radionuclide therapy and its daughter radionuclides may accumulate around the patient. However, the concentration of these radon daughters during alpha radionuclide therapy was not obvious. Here, we first detected the radon daughters of Rn-219 around patients during alpha radionuclide therapy. While the Ra-223-administered patients were in a room for ~1.5 hours, the radon daughter concentration increased to 4 to 5 times higher than without the patients. When the patients were in the room, the energy spectra of the alpha particles in the air showed the peak of the radon daughter of Rn-219, Bi-211 (6.6 MeV), which was different from that without the patients. We conclude that the daughter radionuclides of Rn-219 are accumulated around the patient, and the concentration was higher than that of the natural radon daughters. However, the increase in levels of alpha emitters, while detectable, is lower than the daily variations and thus is likely not a source of concern for radiation exposure.

BACKGROUND AND PURPOSE: Despite the development of neuroimaging, identification of focal cortical dysplasia remains challenging. The purpose of this study was to show the longitudinal changes of MR imaging and FDG-PET in patients with West syndrome and subtle focal cortical dysplasia. MATERIALS AND METHODS: Among 52 consecutive patients with West syndrome, 4 were diagnosed with subtle focal cortical dysplasia on 3T MR imaging. MR imaging and PET findings were evaluated longitudinally at onset and at 12 and 24 months of age. RESULTS: At the onset of West syndrome, MR imaging demonstrated focal signal abnormalities of the subcortical white matter in 2 patients. In the other 2 patients, focal subcortical high-intensity signals became visible on follow-up T2WI as myelination progressed. PET at onset showed focal cortical hypometabolism in 3 patients, with 1 of these patients also having focal hypermetabolism and 1 having normal findings. On PET at 24 months, hypometabolism persisted in 2 patients and disappeared in 1, and hypermetabolism disappeared in 1. In 1 patient with normal MR imaging and PET findings at onset, focal hyperintensity and hypometabolism first appeared at 24 months of age. The findings on MR imaging and PET in these patients evolved differently with brain maturation and the clinical course. CONCLUSIONS: Subtle focal cortical dysplasia can be undetectable on MR imaging at the onset of West syndrome and is not always accompanied by hypometabolism or hypermetabolism on PET. Longitudinal MR imaging and PET studies may be useful for detecting such lesions. Even in West syndrome with a congenital structural abnormality, PET findings evolve differently with brain maturation and the clinical condition.

To identify prognostic factors associated with a low-iodine diet (LID) and the amount of remnant thyroid tissue in Japanese patients with differentiated thyroid cancer (DTC) who received initial I-131 remnant ablation (RAI) using a fixed low dose of I-131 (1110 MBq). In this prospective study, we enrolled 45 patients. Patients were classified into a self-managed LID group and a strict LID group. We measured the urinary iodine concentration on the day of RAI after patients consumed LID for 2 weeks. Thyroid-stimulating hormone-induced thyroglobulin (Tg) levels and I-131 uptake by the remnant thyroid tissue were also evaluated. A response-evaluation whole-body scan (WBS) was performed 6–8 months after RAI to determine the outcome of the therapy. Post-LID urinary iodine levels of the strict LID group tended to be lower than those of the self-managed LID group. Twenty-five cases (56%) showed absence of uptake, whereas 20 cases (44%) showed residual uptake on the response-evaluation WBS. There were no significant differences between “absence” and “residual” groups in urinary iodine concentrations and Tg levels (p = 0.253 and p = 0.234, respectively). However, significant differences were observed in I-131 uptake by the thyroid bed (p = 0.035). For patients following the current Japanese method of a 2-week LID, the urinary iodine concentration was not a predictive factor for the successful outcome of RAI. In contrast, low I-131 uptake by the thyroid bed, revealed by the scintigram after RAI, may serve as a favorable predictive factor.

Histological chorioamnionitis (CAM) is one form of intrauterine inflammation that is often seen in cases of preterm birth and are usually confirmed based on pathological examination after delivery. Histological CAM is related to significant neonatal morbidity and mortality; however, its etiology is unknown. The objective of this study was to determine the risk factors for histological CAM, using medical background, including fetal heart rate (FHR) patterns in preterm birth cases. The preterm birth cases delivered between 28 and 36 weeks were categorized into two groups according to the presence of histological CAM. Ninety-five preterm infants were included: 48 infants without histological CAM and 47 cases with histological CAM. The odds ratio for histological CAM was adjusted for FHR patterns, gestational age, and delivery mode (vaginal delivery or Caesarean section). Logistic regression analysis showed that vaginal delivery and gestational age were associated with histological CAM (odds Ratio [OR]: 3.1, 95% confidence interval [CI]: 1.0-9.4, p < 0.05, and OR: 0.8, 95% CI: 0.6-0.9, p < 0.05, respectively). However, there were no specific FHR patterns associated with histological CAM. Our study indicates that in preterm birth cases, histological CAM is not related to any specific FHR pattern. However, labor uterine contraction and immature gestational age at the delivery are related to histological CAM. These results may provide better delivery management methods for preterm birth cases.

Statistical image analysis of brain SPECT images has improved diagnostic accuracy for brain disorders. However, the results of statistical analysis vary depending on the institution even when they use a common normal database (NDB), due to different intrinsic spatial resolutions or correction methods. The present study aimed to evaluate the correction of spatial resolution differences between equipment and examine the differences in skull bone attenuation to construct a common NDB for use in multicenter settings. The proposed acquisition and processing protocols were those routinely used at each participating center with additional triple energy window (TEW) scatter correction (SC) and computed tomography (CT) based attenuation correction (CTAC). A multicenter phantom study was conducted on six imaging systems in five centers, with either single photon emission computed tomography (SPECT) or SPECT/CT, and two brain phantoms. The gray/white matter I-123 activity ratio in the brain phantoms was 4, and they were enclosed in either an artificial adult male skull, 1300 Hounsfield units (HU), a female skull, 850 HU, or an acrylic cover. The cut-off frequency of the Butterworth filters was adjusted so that the spatial resolution was unified to a 17.9 mm full width at half maximum (FWHM), that of the lowest resolution system. The gray-to-white matter count ratios were measured from SPECT images and compared with the actual activity ratio. In addition, mean, standard deviation and coefficient of variation images were calculated after normalization and anatomical standardization to evaluate the variability of the NDB. The gray-to-white matter count ratio error without SC and attenuation correction (AC) was significantly larger for higher bone densities (p

Aim We sought to identify the relationship between regional cerebral blood flow (rCBF) and error types on the Clock Drawing Test (CDT) in patients with Alzheimer's disease (AD). Method The CDT was administered to 142 patients with AD. We used the Mendez scoring method. Their rCBF values were measured by single-photon emission computed tomography. The correlation between the CDT total score and rCBF was examined on a voxel-by-voxel basis. After we excluded 37 patients whose drawings were inappropriate for assessing the CDT error types, we examined the relationships between each error type on the CDT and rCBF. Results Total score on the CDT was positively correlated with rCBF in the left posterior middle temporal lobe. We also found relationships between the error “non-existence of number 2, or not pointing toward number 2” and the left frontal lobe; the error “uneven number spacing” and the bilateral frontal lobe; “deviation of the clock center” and the left frontal lobe; “missing numbers” and the right parietal lobe; “uneven number distance from edge” and the right parietal and the temporal lobes; “same length hands” and the bilateral temporal lobe; and “unclosed circle” and the left temporal lobe. Conclusions Each error type on the CDT appears to relate to a different brain region. These findings will be useful in the understanding of CDT performances and the underlying neuropsychological pathology. Geriatr Gerontol Int 2016; 16: 777–784.

Accurate preoperative evaluation of lymph nodes can provide optimal treatment for patients. However, in patients with clinical N1 disease (cN1) non-small cell lung cancer (NSCLC), no suitable predictor has been identified for hilar/intrapulmonary lymph node metastasis (pathological N1 disease; pN1). The purpose of this study was to identify pN1 in cN1 NSCLC patients. We retrospectively reviewed the clinicoradiological features of 109 patients with a discrete type of cN1 NSCLC who had undergone complete resection at our institution from 2004 to 2015. The association between clinicoradiological variables and nodal status was analyzed to identify predictors for pN1. The cohort consisted of 77 males and 32 females, ranging in age from 39 to 84 years. The breakdown by pathological N category was 40 (37%) pN0, 41 (38%) pN1, and 28 (25%) pN2 patients. Maximum lymph node diameter was identified as a significant predictor for pN1, with an odds ratio of 1.25 (P = 0.010). When limited to 63 patients who underwent positron emission tomography (FDG-PET) at our institution, the maximum standardized uptake value (SUVmax) of the lymph node was an independent predictor, with an odds ratio of 1.91 with logistic regression analysis (P = 0.004). The size of lymph node and the SUVmax were significant factors for pN1, with optimal cut-off values of 13 mm and 4.28, respectively. Among the patients with cN1, maximum lymph node size and SUVmax of the FDG-PET were significant predictors for pN1.

Purpose To compare dual-phase dual-energy CT (DE-CT) with FDG-PET/CT for predicting histopathological locoregional invasiveness of non-small cell lung cancers (NSCLCs). Materials and methods We selected 63 consecutive patients with NSCLC lesions (37 males, 26 females; age range, 44–85 years; mean age, 69 years) who were evaluated preoperatively by both DE-CT and PET/CT at our institution. Postoperative microscopic invasiveness (lymphatic permeation, vascular invasion, and/or pleural involvement) was reviewed, and we defined locoregionally invasive tumors as those that had at least one positive finding of microscopic invasiveness. DE-CT scanning in the arterial and delayed phases was performed after injection of iodinated contrast media using 140-kVp and 80-kVp tube voltages. Three-dimensional iodine-related attenuation of primary tumors in the arterial and delayed phases was quantified automatically using “syngo Dual Energy Lung Nodules” application software, and the ratio of arterial phase to delayed phase enhancement (A/D ratio) was calculated. The A/D ratio and SUVmax on PET/CT were evaluated with respect to postoperative invasiveness by univariate logistic regression analysis. Results The A/D ratio was significantly correlated with lymphatic permeation, vascular invasion, and pleural involvement (p = 0.011, p = 0.021, and p = 0.010, respectively). In contrast, the SUVmax was significantly correlated with pleural involvement (p = 0.020) but not with lymphatic permeation or vascular invasion (p = 0.088 and p = 0.100, respectively). In the subgroup of patients with lesion diameters ≤2 cm, the A/D ratio was significantly correlated with locoregional invasiveness (p = 0.040), while the SUVmax was not (p = 0.121). Conclusion For the prediction of microscopic invasiveness of NSCLCs, the diagnostic performance of dual-phase DE-CT may be comparable to that of FDG-PET/CT.

We investigated the role ofFourteen patients with thymic epithelial tumors who underwent PET-CT before and after induction therapy were retrospectively analyzed. The relationship between the change in the maximum standardized uptake value (SUVThe study cohort consisted of 5 males and 9 females. Nine of the patients had thymoma, and 5 had thymic carcinoma. The induction therapy included chemotherapy in 9 cases, chemoradiation therapy in 4 cases and radiation therapy in 1 case. Among the 8 patients with a pathologic response of Ef0/1, 5 were clinically evaluated as having stable disease (SD), while 3 were found to have had a partial response (PR). The SUVIn comparison with CT, PET-CT seems to be useful for predicting the pathologic response to induction therapy in patients with thymic epithelial tumors.