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We evaluated the vascularity of retained products of conception (RPOC) using arterial spin-labeling magnetic resonance imaging (ASL-MRI) to clarify the clinical feasibility of this approach. A pulsed-continuous ASL sequence with echo-planar imaging (EPI) acquisitions was used. Ten consecutive patients with RPOC were enrolled. All ASL images were evaluated visually and semiquantitatively and compared with the findings of Doppler ultrasound (US) and dynamic contrast-enhanced MRI (DCE-MRI). The technical success rate was 93.7% (15/16 scans). One failed case was excluded from the analysis. Six patients showed quite high signals over RPOC, while three patients showed no abnormal signals. Doppler US alone failed to detect the hypervascular area in two cases, and ASL-MRI alone failed in three. A significant linear correlation was found between semiquantitative values of ASL-MRI and DCE-MRI. All six patients showing high signals on ASL-MRI underwent follow-up MRI after therapy. High signals in five patients decreased visually and semiquantitatively, while one patient showed signal increases. Evaluation of RPOC using ASL-MRI was clinically feasible and response to therapy could be evaluated. However, the clinical advantages over conventional imaging remain unclear and need to be evaluated.

The use of computed tomography (CT) has increased dramatically over the past several decades and has resulted in a concurrent increase in medical exposure to ionizing radiation. Several recent studies have examined the link between medical radiation and the risk of cancer, especially in children. The cancer risk associated medical exposure has not been definitively confirmed. However, we have to reduce unwarranted medical radiation exposure in pediatric patients. Justification and optimization are of great importance in order to minimize these risks, and the standardization of CT usage is essential. However, in Japan no clinical guidelines for the use of CT have been commonly agreed upon, especially in children. Furthermore, the CT-associated radiation exposure in Japan varies widely among the different facilities. Further studies based on a nationwide survey in Japan will be required in order to establish simple and useful clinical guidelines., Journal of Radiation Research, 59(suppl 2), pp.ii130-ii136; 2018

PURPOSE To assess the segmental difference of liver fibrosis during the progression of chronic liver disease (CLD) using hepatic extracellular volume fractions (fECVs) obtained by dual-energy CT. METHODS A total of 218 patients (92 men and 126 women; mean age, 67.8 ± 11.7 years) with CLD and 85 patients (44 men and 41 women; mean age, 62.8 ± 13.7 years) without CLD as a control underwent dual-energy computed tomography (CT) of the liver (5-min equilibrium phase images). The iodine densities of the lateral, medial, anterior, and posterior segments and the aorta were measured, and fECVs were calculated. Comparisons of the fECV of each segment and for each albumin-bilirubin (ALBI) grade were then statistically analyzed. RESULTS In the control group and ALBI grades 1 and 3, no significant difference in fECV was found between each segment, whereas in ALBI grade 2, the fECVs were significantly larger in the medial and anterior than in the other segments (p

The aim of this study was to retrospectively evaluate the clinical significance of 18F-FDG PET/CT textural features for discriminating uterine sarcoma from leiomyoma. Fifty-five patients with suspected uterine sarcoma based on ultrasound and MRI findings who underwent pretreatment 18F-FDG PET/CT were included. Fifteen patients were histopathologically proven to have uterine sarcoma, 14 patients by surgical operation and one by biopsy, and 40 patients were diagnosed with leiomyoma by surgical operation or in a follow-up for at least 2 years. A texture analysis was performed on PET/CT images from which second- and higher order textural features were extracted in addition to standardized uptake values (SUVs) and other first-order features. The accuracy of PET features for differentiating between uterine sarcoma and leiomyoma was evaluated using a receiver-operating-characteristic (ROC) analysis. The intratumor distribution of 18F-FDG was more heterogeneous in uterine sarcoma than in leiomyoma. Entropy, correlation, and uniformity calculated from normalized gray-level co-occurrence matrices and SUV standard deviation derived from histogram statistics showed greater area under the ROC curves (AUCs) than did maximum SUV for differentiating between sarcoma and leiomyoma. Entropy, as a single feature, yielded the greatest AUC of 0.974 and the optimal cut-off value of 2.85 for entropy provided 93% sensitivity, 90% specificity, and 92% accuracy. When combining conventional features with textural ones, maximum SUV (cutoff: 6.0) combined with entropy (2.85) and correlation (0.73) provided the best diagnostic performance (100% sensitivity, 94% specificity, and 95% accuracy). In combination with the conventional histogram statistics and/or volumetric parameters, 18F-FDG PET/CT textural features reflecting intratumor metabolic heterogeneity are useful for differentiating between uterine sarcoma and leiomyoma.

The American Association of Physicists in Medicine (AAPM) Working Group on TG‐51 published an Addendum to the AAPM's TG‐51 protocol (Addendum to TG‐51) in 2014, and the Japan Society of Medical Physics (JSMP) published a new dosimetry protocol JSMP 12 in 2012. In this study, we compared the absorbed dose to water determined at the reference depth for high‐energy photon beams following the recommendations given in AAPM TG‐51 and the Addendum to TG‐51, IAEA TRS‐398, and JSMP 12. This study was performed using measurements with flattened photon beams with nominal energies of 6 and 10 MV. Three widely used ionization chambers with different compositions, Exradin A12, PTW 30013, and IBA FC65‐P, were employed. Fully corrected charge readings obtained for the three chambers according to AAPM TG‐51 and the Addendum to TG‐51, which included the correction for the radiation beam profile (P rp), showed variations of 0.2% and 0.3% at 6 and 10 MV, respectively, from the readings corresponding to IAEA TRS‐398 and JSMP 12. The values for the beam quality conversion factor k Q obtained according to the three protocols agreed within 0.5%; the only exception was a 0.6% difference between the results obtained at 10 MV for Exradin A12 according to IAEA TRS‐398 and AAPM TG‐51 and the Addendum to TG‐51. Consequently, the values for the absorbed dose to water obtained for the three protocols agreed within 0.4%; the only exception was a 0.6% difference between the values obtained at 10 MV for PTW 30013 according to AAPM TG‐51 and the Addendum to TG‐51, and JSMP 12. While the difference in the absorbed dose to water determined by the three protocols depends on the kQ and P rp values, the absorbed dose to water obtained according to the three protocols agrees within the relative uncertainties for the three protocols.

Complete obliteration of treated arteriovenous malformations (AVMs) can be diagnosed only by confirming the disappearance of arterio-venous (A-V) shunts with invasive catheter angiography. The authors evaluated whether non-invasive arterial spin labeling (ASL) magnetic resonance (MR) imaging can be used to diagnose the obliteration of AVMs facilitate the diagnosis of AVM obliteration after treatment with stereotactic radiosurgery (SRS).Seven patients with a cerebral AVM treated by SRS were followed up with ASL images taken with a 3T-MR unit, and received digital subtraction angiography (DSA) after the AVM had disappeared on ASL images. Three patients among the seven received DSA also after the postradiosurgical AVM had disappeared on conventional MR images but A-V shunt was residual on ASL images. Four patients among the seven received contrast-enhanced (CE) MR imaging around the same period as DSA.ASL images could visualize postradiosurgical residual A-V shunts clearly. In all seven patients, DSA after the disappearance of A-V shunts on ASL images demonstrated no evidence of A-V shunts. In all three patients, DSA after the AVM had disappeared on conventional MR images but not on ASL images demonstrated residual A-V shunt. CE MR findings of AVMs treated by SRS did not correspond with DSA findings in three out of four patients.Findings of radiosurgically treated AVMs on ASL images corresponded with those on DSA. The results of this study suggest that ASL imaging can be utilized to follow up AVMs after SRS and to decide their obliteration facilitate to decide the precise timing of catheter angiography for the final diagnosis of AVM obliteration after SRS.

Objectives The aims of our study were to find the textural features on 18F-FDG PET/CT which reflect the different histological architectures between cervical cancer subtypes and to make a visual assessment of the association between 18F-FDG PET textural features in cervical cancer.

This study was performed primarily to clarify whether pathological analysis of cadavers for anatomical dissection is possible using postmortem imaging (PMI), and whether this is worthwhile. A total of 33 cadavers that underwent systematic anatomical dissection at our medical school also underwent PMI. Fixative solution was injected into the corpus 3-4 days after death. PMI was then performed using an 8-slice multi-detector CT scanner 3 months before dissection. Before dissection, a conference was held to discuss the findings of the PMI. First, two radiologists read the postmortem images without any medical information and deduced the immediate cause of death. Then, the anatomy instructor revealed the medical information available. Based on this information, the radiologist, anatomy instructor, and pathologists suggested candidate sampling sites for pathological examination. On the last day of the dissection period, the pathologists resected the sample tissues and processed them for pathological examination. In 12 of 33 cases, the presumed causes of death could be determined based on PMI alone, and revision of the cause of death described in the death certificate was considered in five (15.2%) cases, based on PMI and pathological analysis. This article presents a novel method of pathological analysis of cadavers for anatomical dissection using PMI without disturbing the anatomy education of medical students.

To optimize the delays alternating with nutation for tailored excitation (DANTE) pulse as a vascular crushing gradient to eliminate macro-and micro-vascular signals and to generate a macrovascular space-related map by applying DANTE with multiple conditions. Numerical simulation was performed to estimate the optimal flip angle (FA) of the DANTE. A phantom study was conducted to evaluate the impact of the FA and gradient area (GA) of the DANTE with three flow velocities and various parameters of the DANTE. Finally, an in vivo study was performed to assess the optimal DANTE parameters and to map the estimated macrovascular signal of the arterial spin labeling (ASL) signal. Numerical simulation revealed that the decrease of magnetization plateaued at 12.5° of FA. The phantom study showed that the setting of larger FA or GA decreased the ASL signals. The decrease of the ASL signal depended on the flow velocity, and the dependence increased with decreasing GA. The in vivo study revealed that larger FA and GA decreased the perfusion signal. An optimized DANTE makes it possible to efficiently suppress the macro-and-micro vascular signals depending on the flow velocity. Moreover, macrovascular signal mapping may be useful to assess altered hemodynamic states.

Background The signal intensity obtained by arterial spin labeling (ASL) depends not only on perfusion signal, but also on arterial transit time (ATT). Although ATT has a more significant effect on accurate regional cerebral blood flow (CBF) calculations, the multiple post-labeling delay (PLD) approach is difficult to use in routine examinations. Purpose To optimize imaging parameters for labeling duration (LD) and PLD and to confirm their validity in long-labeled pseudo-continuous ASL. Material and Methods The perfusion signal was simulated in four LDs and theoretical signal-to-noise ratio efficiency (SNReff) was calculated. In vivo studies were performed on a 3.0 T magnetic resonance imaging (MRI) scanner and 15 volunteers were categorized into either the young or elderly adult groups. We compared the differences in CBF values with or without ATT correction. Results Regarding signal simulation, perfusion signal increased with the length of LD. SNReff also improved with LD, but SNReff plateaued at an LD of 3.0 s. As for the in vivo study, SNR linearly increased along with the LD. The CBF differences with the correction of ATT were larger in the elderly adult group. This trend was most prominent in the longer ATT area in the occipital cortical region. Conclusion A combination of imaging settings of LD = 3.5 s and PLD = 2.0 s were suggested as optimal imaging parameters for allowing acceptable CBF quantification and sufficient SNR in both young and elderly individuals.

Despite 75 to 90 % physician accuracy in determining the underlying cause of death, precision of determination of the immediate cause of death is approximately 40 %. In contrast, two thirds of immediate causes of death in hospitalized patients are correctly diagnosed by postmortem computed tomography (CT). Postmortem CT might provide an alternative approach to verifying the immediate cause of death. To evaluate the effectiveness of postmortem CT as an alternative method to determine the immediate cause of death in hospitalized patients, an autopsy-based prospective study was performed. Of 563 deaths from September 2011 to August 2013, 50 consecutive cadavers undergoing hospital autopsies with consent for additional postmortem CT at the University of Fukui were enrolled. The accuracy of determination of the immediate cause of death by postmortem CT was evaluated in these patients. Diagnostic discrepancy was also compared between radiologists and attending physicians. The immediate cause of death was correctly diagnosed in 37 of 50 subjects using postmortem CT (74 %), concerning 29 cases of respiratory failure, 4 of hemorrhage, 3 of liver failure and 1 of septic shock. Six cases of organ failure involving 13 patients were not identified as the cause of death by postmortem CT. Regarding the immediate cause of death, accuracy of clinical diagnosis was significantly lower than that of postmortem CT (46 vs 74 %, P

Background: The purpose of this study was to explore the relation between muscle MRI findings and weakness of the upper extremity muscles in patients with myotonic dystrophy type 1 (DM1). Methods: Nineteen DM1 patients from 15 families were enrolled in this study. Muscle weakness was evaluated using the modified Medical Research Council scale. Subjects also underwent a genetic study and muscle MRI of the upper extremities. Results: In patients with DM1, the flexor digitorum profundus (FDP), flexor pollicis longus, flexor digitorum superficialis (FDS), extensor pollicis, abductor pollicis longus (APL), lateral head of triceps brachii and infraspinatus (INF) muscles were frequently and severely affected. Muscle strength was significantly correlated with the severity of muscle MRI findings in the FDP, short head of biceps brachii (SBB), and medial head of triceps brachii muscles. Disease duration was correlated significantly with MRI findings in the FDP, FDS, long head of biceps brachii, INF, APL, and SBB muscles. Unexpectedly, the degree of trinucleotide expansion of myotonin protein kinase was not correlated with muscle MRI findings. Conclusion: Muscle MRI of the upper extremity is useful to detect affected muscles in DM1 patients.

Although folate deficiency was reported to be associated with hyperhomocysteinemia, influence of folate supplementation on cognition remains controversial. Therefore, we explored the effects of folate supplementation on the cognition and Homocysteine (Hcy) level in relatively short periods in patients with folate deficiency and cognitive impairment. Enrolled 45 patients (mean age of 79.7 &plusmn, 7.9 years old) with folate deficiency (&lt, 3.6 ng/mL) with cognitive impairment underwent Mini-Mental State Examination (MMSE), and laboratory examinations, including folate, vitamin B12, and Hcy. The degree of hippocampal atrophy in MRI was estimated using a voxel-based specific regional analysis system for Alzheimer&rsquo, s disease (VSRAD). Patients were administrated folate (5 mg/day), then Hcy, and MMSE score were re-examined after 28 to 63 days. Mean Hcy significantly decreased from 25.0 &plusmn, 18.0 to 11.0 &plusmn, 4.3 nmol/mL (p &lt, 0.001). Average MMSE scores also significantly changed from 20.1 &plusmn, 4.7 to 22.2 &plusmn, 4.3 (p &lt, 0.001). The degree of change in the MMSE score and basic Hcy or Hcy change was significantly positively correlated, while degree of hippocampal atrophy in MRI did not. Although several factors should be taken into account, folate supplementation ameliorated cognitive impairment, at least for a short period, in patients with folate deficiency.

Purpose Hashimoto encephalopathy (HE) is an autoimmune-mediated encephalopathy associated with anti-thyroid antibodies. We previously discovered serum autoantibodies against the NH2-terminal of α-enolase (NAE), which serve as a specific diagnostic biomarker for HE and may be involved in the autoimmune pathophysiology of HE, including vasculitis. Although the common findings of brain magnetic resonance imaging (MRI) in HE have been recognized as normal or non-specific white matter lesions, serial MRI changes have been less well studied. The aim of this study was to clarify detailed and longitudinal MRI changes in HE associated with anti-NAE antibodies. Methods We investigated serial brain MR images in 12 Japanese patients with HE who had serum anti-NAE antibodies. Results Brain MRI showed diffuse white matter abnormalities and/or multiple small subcortical lesions in 10 patients. These lesions were apparently non-specific; however, in 7 of these patients we observed expanding and diminishing white matter lesions, emerging subcortical high-intensity spots on diffusion-weighted images, or reversible limbic lesions, which worsened at relapse and improved after recovery following immunotherapies. Conclusion MRI lesions that fluctuate according to the disease condition were frequently observed in HE patients with anti-NAE antibodies, which suggests that these fluctuation may be associated with the autoimmune pathophysiology of HE.

Synthetic magnetic resonance imaging (MRI) allows the production of images with any contrast from a single scan after quantification. The combined T

Background Uncertainty in the calibration of high-energy radiation sources is dependent on user and equipment type. Aim We evaluated the uncertainty in the positioning of a cylindrical chamber at a reference depth for reference dosimetry of high-energy photon beams and the resulting uncertainty in the chamber readings for 6- and 10-MV photon beams. The aim was to investigate major contributions to the positioning uncertainty to reduce the uncertainty in calibration for external photon beam radiotherapy. Materials and methods The following phantoms were used: DoseView 1D, WP1D, 1D SCANNER, and QWP-07 as one-dimensional (1D) phantoms for a vertical-beam geometry; GRI-7632 as a phantom for a fixed waterproofing sleeve; and PTW type 41023 and QWP-04 as 1D phantoms for a horizontal-beam geometry. The uncertainties were analyzed as per the Guide to the Expression of Uncertainty in Measurement. Results The positioning and resultant uncertainties in chamber readings ranged from 0.22 to 0.35 mm and 0.12–0.25%, respectively, among the phantoms (using a coverage factor k = 1 in both cases). The major contributions to positioning uncertainty are: definition of the origin for phantoms among users for the 1D phantoms for a vertical-beam geometry, water level adjustment among users for the phantom for a fixed waterproofing sleeve, phantom window deformation, and non-water material of the window for the 1D phantoms for a horizontal-beam geometry. Conclusion The positioning and resultant uncertainties in chamber readings exhibited minor differences among the seven phantoms. The major components of these uncertainties differed among the phantom types investigated.

// Tetsuya Tsujikawa 1 , Hideaki Tsuyoshi 2 , Masafumi Kanno 3 , Shizuka Yamada 2 , Masato Kobayashi 4 , Norihiko Narita 3 , Hirohiko Kimura 5 , Shigeharu Fujieda 3 , Yoshio Yoshida 2 and Hidehiko Okazawa 1 1 Biomedical Imaging Research Center, University of Fukui, Fukui, Japan 2 Department of Obstetrics and Gynecology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 3 Department of Otolaryngology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 4 Wellness Promotion Science Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 5 Department of Radiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan Correspondence to: Tetsuya Tsujikawa, email: awaji@u-fukui.ac.jp Keywords: PET radiomic features; PET/CT; PET/MR Received: November 27, 2017 Accepted: March 24, 2018 Published: April 17, 2018 ABSTRACT Purpose: We investigated whether PET radiomic features are affected by differences in the scanner, scan protocol, and lesion location using 18 F-FDG PET/CT and PET/MR scans. Results: SUV, TMR, skewness, kurtosis, entropy, and homogeneity strongly correlated between PET/CT and PET/MR images. SUVs were significantly higher on PET/MR 0-2 min and PET/MR 0-10 min than on PET/CT in gynecological cancer ( p = 0.008 and 0.008, respectively), whereas no significant difference was observed between PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min images in oral cavity/oropharyngeal cancer. TMRs on PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min increased in this order in gynecological cancer and oral cavity/oropharyngeal cancer. In contrast to conventional and histogram indices, 4 textural features (entropy, homogeneity, SRE, and LRE) were not significantly different between PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min images. Conclusions: 18 F-FDG PET radiomic features strongly correlated between PET/CT and PET/MR images. Dixon-based attenuation correction on PET/MR images underestimated tumor tracer uptake more significantly in oral cavity/oropharyngeal cancer than in gynecological cancer. 18 F-FDG PET textural features were affected less by differences in the scanner and scan protocol than conventional and histogram features, possibly due to the resampling process using a medium bin width. Methods: Eight patients with gynecological cancer and 7 with oral cavity/oropharyngeal cancer underwent a whole-body 18 F-FDG PET/CT scan and regional PET/MR scan in one day. PET/MR scans were performed for 10 minutes in the list mode, and PET/CT and 0–2 min and 0–10 min PET/MR images were reconstructed. The standardized uptake value (SUV), tumor-to-muscle SUV ratio (TMR), skewness, kurtosis, entropy, homogeneity, short-run emphasis (SRE), and long-run emphasis (LRE) were compared between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images.

PURPOSE The aim of this study was to investigate the potential of PET imaging with a hypoxia-selective tracer ⁶²Cu-diacetyl-bis(N⁴-methylthiosemicarbazone) (⁶²Cu-ATSM) for evaluating the prognosis of patients with head and neck cancer (HNC). METHODS Twenty-five patients with HNC including stage II to IV underwent both ⁶²Cu-ATSM and ¹⁸F-FDG PET before the initiation of treatment. Volumes of interest were placed on the tumor and sternocleidomastoid muscles to obtain SUVmax and to calculate the tumor-to-muscle activity ratio (TMR). The PET results were correlated with clinical follow-up, and the receiver operating characteristic analysis was used to determine the optimal cutoff values. Progression-free survival (PFS) and cause-specific survival (CSS) were statistically analyzed. RESULTS Patients were followed up for periods ranging from 4 to 32 months. Twelve patients died from local recurrence or metastasis of a primary cancer, and 2 had recurrence of the 13 remaining patients. Mean (SD) periods of PFS and CSS were 15.5 (12.5) and 18.6 (11.0) months, respectively. Optimal cutoff values for each PET index were as follows: SUVs of ⁶²Cu-ATSM (SUVATSM) and FDG were 3.6 and 7.9; TMRs of ATSM (TMRATSM) and FDG were 3.2 and 5.6. When the cutoff for TMRATSM was set at 3.2, patients with a greater TMRATSM had significantly worse PFS (P = 0.014) and CSS (P = 0.031). Two-year PFS and CSS rates were 73% and 80% for patients with a lower TMRATSM (≤3.2); however, they were 20% and 33% for those with hypoxic tumors (TMRATSM, >3.2), respectively. F-FDG-related indices did not show any significant difference in either PFS or CSS. CONCLUSIONS Pretreatment ⁶²Cu-ATSM PET is useful for predicting the prognosis of patients with HNC.

Background FDG-PET/CT is a robust tool for staging of lung cancer, but the differences in FDG uptake between primary and metastatic lesions have not yet been well described. Purpose To define the potential range of standardized uptake value (SUV) differences between primary and metastatic lesions in lung cancer patients and to identify the factors responsible for these differences. Material and Methods FDG-PET/CT images of 75 lung cancers with 296 metastases were analyzed retrospectively. Histological types, primary locations, and metastatic sites were recorded. The average and maximum SUV (SUVavg, SUVmax) of each primary tumor and metastasis were measured, and the ratio of metastatic SUVs to primary SUVs (M/Pavg, M/Pmax), its difference from 100% (diff-M/Pavg, diff-M/Pmax), the ratio of ROI area of metastatic to primary lesions (ROI-M/P), and its difference from 100% (diff-ROI-M/P) were calculated. Results M/Pavg was in the range of 35.9–224.6% (mean ± SD: 97.9% ± 35.9%), while M/Pmax was in the range of 24.8–286.7% (98.1% ± 45.3%). Furthermore, values were in the range of 50–200% for M/Pavg in 280/296 lesions (94.6%) and for M/Pmax in 255/296 lesions (86.1%). M/Pavg and M/Pmax showed significant linear correlations with ROI-M/P (r = 0.62, 0.64, respectively). Multivariate analysis showed that diff-ROI-M/P had the greatest effect on diff-M/Pavg and diff-M/Pmax. Conclusion The SUVs of most metastatic lesions ranged from half to double those of primaries in lung cancer patients. When the SUV of a suspected metastasis is beyond the range of half to double that of the primary lung cancer, other non-metastatic lesions should be considered, while taking ROI size into account.

We evaluated bleb fluid images taken after Baerveldt glaucoma implantation. T2-weighted images of bleb fluid were scanned with 3 Tesla magnetic resonance imaging in 52 patients who had undergone tube-shunt surgery using the 350-mm2 endplate Baerveldt glaucoma implant; three-dimensional images were constructed from these images. Bleb fluid images were classified into either a layer of bleb fluid on either side of the endplate (double bleb layer group; n = 24) or one layer outside the endplate (single bleb layer group; n = 28). Despite there being no correlation between the bleb volume and the postoperative IOP (r = −0.080; P = 0.57), the double bleb layer group had significantly lower postoperative IOPs than the single bleb layer group (12.3 ± 3.8 mmHg vs. 14.7 ± 4.1 mmHg, respectively; P = 0.033). The single bleb layer was significantly related to higher numbers of prior intraocular surgeries (relative risk = 2.85; P = 0.0014). Formation of a layer of bleb fluid on either side of the endplate may have resulted in the lower postoperative IOPs after Baerveldt glaucoma implantation. Repeated intraocular surgery adversely affects formation of the double bleb layer.

We investigated the correlation between tumor blood flow (TBF) and histopathologic features of Warthin tumors (WTs) and pleomorphic adenomas (PAs) to determine the TBF in the differential diagnosis of these tumors and evaluated how well pCASL-MRI can differentiate PAs from WTs compared to conventional MRI.The ADC, time intensity curve (TIC) pattern of dynamic contrast enhancement, and pCASL (visual assessment and TBF of the MR images of 10 WTs and 13 PAs) were reviewed. We compared the pCASL and ADC or TIC patterns in WT and PA images. Tissue sections were stained with CD34 to evaluate microvessel density (MVD). The TBF and MVD results were compared. The Mann-Whitney U test was used to compare the TBFs, ADCs, and MVDs of these tumors. The diagnostic accuracy was determined by analyzing the receiver operating characteristic curve.On visual assessment, the signal intensity was higher in all but three cases of WT. The TBF and MVD of the WTs were significantly higher (both, p 0.01) than the PAs, and the ADC was significantly lower (p 0.01). Many WTs had early enhancement of the TIC pattern and high washout; many PAs had gradual enhancement. The diagnostic accuracies of visual analysis, TBF, and ADC for differentiation between WTs and PAs were 91.3, 95.7, and 87.0%, respectively.The TBF were significantly higher in WTs than in PAs, and there was a positive correlation between TBF and MVD. Moreover, pCASL-MRI provides more accurate imaging than conventional MRI to differentiate WTs and PAs.

On arterial spin-labeled (ASL) images, areas of bright intravascular signal will appear when the post labeling delay time is shorter than arterial transit time. Vascular suppression (VS) schemes reduce artefactual bright signal by dephasing intravascular labeled spins. However, existing VS methods, such as Motion-Sensitized Driven-Equilibrium (MSDE), decrease the uniformity of the signal intensity distribution and extend the echo time. The purpose of this study is to compare VS using a Delays Alternating with Nutation for Tailored Excitation (DANTE) preparation pulse, with MSDE for ASL imaging on a flow phantom and volunteer data. In the phantom study, the signal decay pattern of moving water was similar for both methods. In the volunteer study, the bright intravascular signal artifact was decreased by both methods. However right-left differences in signal intensity were smaller using DANTE-prepared ASL. The proposed DANTE-prepared ASL sequence has a vessel suppression effect while maintaining a uniform signal intensity distribution. This study indicates that DANTE is a potentially useful method for vessel suppression in ASL imaging.

Background To examine the utility of diffusion-weighted MRI (DW-MRI) for staging and early response to chemotherapy assessment in lymphoma patients as compared with fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT). Methods Twenty-eight patients with histologically confirmed malignant lymphoma underwent both MRI and FDG-PET/CT before (pretreatment) and after two courses of chemotherapy (mid-treatment). Staging with MRI (DW-MRI alone and with T2-weighted images) and FDG-PET was compared visually, and the concordance rate (kappa value, κ) was calculated. To evaluate early response to chemotherapy, patients were divided into two groups, lesion-positive (LP) and lesion-negative (LN), based on a proposed original criterion. Progression-free survival (PFS) was compared between the groups using the Kaplan-Meier method. Results The stage diagnosed with DW-MRI alone and with FDG-PET/CT was concordant in 22 patients (κ = 0.71; P

Several incidents involving magnetic resonance imaging (MRI) examinations of patients with unchecked MR-unsafe metallic products have been reported. To improve patient safety, we developed a new MRI safety management system for metallic biomedical products and evaluated its efficiency in clinical practice. Our system was integrated into the picture archiving and communication system (PACS) and comprised an MR compatibility database and inquiry-based patient records of internal metallic biomedical products, enabling hospital staff to check MR compatibility by product name. A total of 6,637 biomedical implants and devices were listed in this system, including product names and their MR compatibilities. Furthermore, MRI histories for each patient at our hospital were also recorded. Using this system, it was possible to confirm the MR compatibility of the patients' metallic biomedical products effectively and to reduce the number of unchecked internal products through systematic patient inquiry. In conclusion, our new system enhanced metallic biomedical product checking procedures, and improved patient safety during clinical MRI examinations.

In stroke-like episodes (SEs) of patients with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), the detection of preclinically latent lesions is a challenge. We report regional cerebral hyperperfusion observed on arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) in the preclinical phase more than 3 months before the clinical onset of SEs in 3 MELAS patients. These hyperperfused areas were not detected by conventional MRI in the preclinical phase and developed into acute lesions at the clinical onset of SEs, suggesting that ASL imaging has the potential for predicting the emergence of SEs.

Purpose To evaluate the feasibility of diffusion-weighted magnetic resonance imaging (DW-MRI) for assessment of the early response to chemotherapy and outcome in patients with advanced lung cancer through comparison with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT). Materials and Methods Twenty-eight lung cancer patients underwent DW-MRI, FDG-PET, and CT before and after one course of chemotherapy. Changes in the apparent diffusion coefficient (ΔADC), the mean standardized uptake value (ΔSUV), and the maximum diameter (ΔMD) were measured and compared. According to the response evaluation criteria, patients were divided into two groups, responders and nonresponders, and progression-free survival (PFS) and overall survival (OS) were estimated. Results The relationship between ΔADC and ΔSUV had the highest correlation coefficient. A cutoff value of ΔADC between responders and nonresponders was estimated as 21.5%. PFS and OS between responders and nonresponders were significantly different on DW-MRI (PFS, P = 0.012; OS, P = 0.006) and on FDG-PET (PFS, P = 0.017; OS, P = 0.036), but not on CT (PFS, P = 0.105; OS, P = 0.051). Conclusion DW-MRI can be used to predict prognosis in patients with advanced lung cancer. J. Magn. Reson. Imaging 2013;38:80–88. © 2012 Wiley Periodicals, Inc.

This study aimed to investigate whether the predictive values of intensity- and volume-based PET parameters are different between histological subtypes in patients with cervical cancer. Ninety patients, 65 with squamous cell carcinoma (SCC) and 25 with non-SCC (NSCC), who underwent pretreatment 18F-FDG PET/CT and pelvic MRI, were studied retrospectively. In addition to SUVmax and SUVmean, metabolic-tumor-volume (MTV) was determined by thresholding of 40% SUVmax and total-lesion-glycolysis (TLG) was calculated. Clinical factors and PET metabolic indices were compared between SCC and NSCC. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method with cut-offs determined by ROC analyses to stratify SCC and NSCC patients separately. Factors associated with survival were assessed with univariate and multivariate analyses using the Cox regression model. No significant differences were observed in clinical factors other than tumor size or 18F-FDG PET metabolic indices between SCC and NSCC. The Kaplan–Meier estimates of 2-year PFS and OS rates were 60% and 70% for SCC and 40% and 76% for NSCC, respectively. Multivariate analyses showed that MTV and TLG were the independent prognostic factors for PFS and OS in SCC; in contrast, SUVmax was the independent prognostic factor for PFS and OS in NSCC. Metabolic burden (MTV and TLG) could be beneficial for the prognostic prediction of cervical SCC patients; in contrast, metabolic intensity (SUVmax) could be beneficial for the prognostic prediction of NSCC patients. The different prognostic implications might be based on the differences of tissue integrity and histological heterogeneity between SCC and NSCC.

Arterial transit time (ATT) is most crucial for measuring absolute cerebral blood flow (CBF) by arterial spin labeling (ASL), a noninvasive magnetic resonance (MR) perfusion assessment technique, in patients with chronic occlusive cerebrovascular disease. We validated ASL-CBF and ASL-ATT maps calculated by pulsed continuous ASL (pCASL) with multiple post-label delay acquisitions in patients with occlusive cerebrovascular disease. Fifteen patients underwent MR scans, including pCASL, and positron emission tomography (PET) scans with 15O-water to obtain PET-CBF. MR acquisitions with different post-label delays (1.0, 1.5, 2.0, 2.5 and 3.0 sec) were also obtained for ATT correction. The theoretical framework of 2-compartmental model (2CM) was also used for the delay compensation. ASL-CBF and ASL-ATT were calculated based on the proposed 2CM, and the effect on the CBF values and the ATT correction characteristics were discussed. Linear regression analyses were performed both on pixel-by-pixel and region-of-interest bases in the middle cerebral artery (MCA) territory. There were significant correlations between ASL-CBF and PET-CBF both for voxel values (r = 0.74 ± 0.08, slope: 0.87 ± 0.22, intercept: 6.1 ± 4.9) and for the MCA territorial comparison in both affected (R2 = 0.67, y = 0.83x + 6.3) and contralateral sides (R2 = 0.66, y = 0.74x + 6.3). ASL-ATTs in the affected side were significantly longer than those in the contralateral side (1.51 ± 0.41 sec and 1.12 ± 0.30 sec, respectively, p

Purpose 18F-FDG PET is used to investigate the metabolic activity of neural tissue. MRI is used to visualize morphological changes, but the relationship between intramedullary signal changes and clinical outcome remains controversial. The present study was designed to evaluate the use of 3-D MRI/18F-FDG PET fusion imaging for defining intramedullary signal changes onMRI scans and local glucose metabolic rate measured on 18F-FDG PET scans in relation to clinical outcome and prognosis. Methods We studied 24 patients undergoing decompressive surgery for cervical compressive myelopathy. All patients underwent 3-D MRI and 18F-FDG PET before surgery. Quantitative analysis of intramedullary signal changes on MRI scans included calculation of the signal intensity ratio (SIR) as the ratio between the increased lesional signal intensity and the signal intensity at the level of the C7/T1 disc. Using an Advantage workstation, the same slices of cervical 3-D MRI and 18F-FDG PET images were fused. On the fused images, the maximal count of the lesion was adopted as the standardized uptake value (SUV max). In a similar manner to SIR, the SUV ratio (SUVR) was also calculated. Neurological assessment was conducted using the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. Results The SIR on T1-weighted (T1-W) images, but not SIR on T2-W images, was significantly correlated with preoperative JOA score and postoperative neurological improvement. Lesion SUVmax was significantly correlated with SIR on T1-W images, but not with SIR on T2-W images, and also with postoperative neurological outcome. The SUVR correlated better than SIR on T1-W images and lesion SUVmax with neurological improvement. Longer symptom duration was correlated negatively with SIR on T1-W images, positively with SIR on T2-W images, and negatively with SUVmax. Conclusion Our results suggest that low-intensity signal on T1-W images, but not on T2-W images, is correlated with a poor postoperative neurological outcome. SUVmax of lesions showing increased signal intensity and SUVR measured on fusion MRI/PET scans are more sensitive parameters for predicting clinical outcome than signal intensity on the MRI scan., European Journal of Nuclear Medicine and Molecular Imaging, 39(10), pp.1528-1537; 2012

A series of N-(trifluoromethyl-2-pyridinyl)alkane- and arenesulfonamides 2-5 have been synthesized by the substitution reaction of 2-chloro(trifluoromethyl)pyridines 6 with alkane- and arenesulfonamides 7. Their inhibitory activities against secretory phospholipase A₂ of porcine pancreas were examined and the analog N-[4,5-bis(trifluoromethyl)-2-pyridinyl]-4-trifluoromethylbenzenesulfonamide 4i was shown to have the highest inhibitory activity, with an IC(50) value of 0.58 mM.

Our aim in this study was to determine an optimal delay time of hepatic arterial phase (HAP) imaging of hypervascular hepatocellular carcinomas (HCCs) in dynamic contrast-enhanced MDCT (DCE-CT) by use of the bolus-tracking method. The time-enhancement curves (TECs) of the aorta and the contrast of the hepatic arterial and portal system (APC) in the pharmacokinetic analysis were calculated. The clinical study included 41 patients with known or suspected HCC who underwent DCE-CT. The TECs of the aorta and the tumor-liver contrast (TLC) in the clinical study were calculated. On pharmacokinetic analysis, the peak aortic enhancement and the peak APC simulated under conditions of an injection duration of 30 s and an iodine load of 500 mg I/kg body weight were observed 18.5 and 22.5 s, respectively, after the trigger threshold (increased CT value 100 Hounsfield units), respectively. In the clinical study, the peak aortic enhancement and the peak TLC were observed 17.2 and 24.8 s after the trigger threshold, respectively. The optimal delay times until peak aortic enhancement and peak HAP were 15-17 and 19-21 s after the trigger threshold, respectively, under the following conditions: injection dose, 500 mg I/kg body weight; injection duration, 30 s; acquisition time, 5 s; and the trigger threshold. In addition, the peak TLC was achieved 4-7 s after the time to peak aortic enhancement.

We recently experienced a case of cerebral infarction incidentally found by whole body bone scintigraphy for the detection of bone metastasis from renal cell carcinoma. Additional bone SPECT and brain MR fusion images clearly demonstrated the wedge-shaped uptake of tracer corresponded to the abnormal intensity reflecting subacute cerebral infarction. Follow-up bone scan and fused images with MRI showed complete resolution of the abnormal uptake in chronic phase. A breakdown in the normal blood-brain barrier results in abnormal ionic calcium flux into the cells following altered cell membrane integrity leading to precipitation of calcium salts which eventually binds to bone imaging tracer such as (99m)Tc-methylene diphosphonate. That is, increased accumulation of bone seeking agents represents lethal cell death. The recent development of software and hardware has enabled the fusion of functional and anatomic images. Image fusion between SPECT with various tracers and MRI is expected to provide clues as to the underlying cause of diseases and to decide our treatment planning in the near future.

Multifractal analysis provides a precise quantitative description of the structural complexity of white matter (WM) on magnetic resonance imaging (MRI). To test this new technique as an aid to elucidating the pathology of schizophrenia, we examined a multifractal dimension (i.e. Deltaalpha) of WM in schizophrenia patients and their relations to clinical variables. We examined 16 patients with schizophrenia and 16 controls matched for age, sex and handedness. Delta alpha value of WM in the prefrontal and frontoparietal lobes and the corpus callosum (genu and splenium) on T2-weighted MRI was calculated. Delta alpha was not significantly different between groups in either region of interest. However, group-by-side interaction for Deltaalpha was found in the frontoparietal WM; post-hoc analysis revealed normal left dominant asymmetry in Deltaalpha for frontoparietal WM in control subjects, which was absent in schizophrenia patients. Furthermore, the patients with schizophrenia had a lower asymmetry coefficient ([R-L]/[R+L]) for Deltaalpha in frontoparietal WM. Relations to clinical symptoms from the Positive and Negative Syndrome Scale, Deltaalpha in corpus callosum, and the asymmetry coefficient in prefrontal WM were correlated with negative and general psychopathology symptom scores. Our results support the left-sided dysfunction hypothesis of schizophrenia and its relation to schizophrenic symptoms. Multifractal analysis reveals abnormal patterns of WM structures in schizophrenia that could be implicated in the disorder's etiology.

Background and Purpose Our intent was to clarify the usefulness of proton magnetic resonance spectroscopy (MRS) and perfusion-weighted magnetic resonance imaging (PW-MRI) in the grading of glioma. Methods Twenty-three consecutive patients with gliomas were investigated by both proton MRS and PW-MRI. For quantitative analysis, the metabolite data of the gliomas were estimated using the LCModel software. Receiver operating characteristic (ROC) curve analyses were also performed to assess which metabolite parameter was optimal for discrimination of glioma grade. From the PW-MRI data, the value of blood volume was measured on the parametric map corresponding to the location of MRS analysis. We then compared tumor blood volume with the amount of choline (Cho). Results The mean Cho/creatine (Cre) ratio was useful to discriminate between Grades II and III, and the mean lactate (Lac)/Cre ratio was found to be significantly different between Grades III and IV. ROC curve analysis showed that measurements involving Cho were superior indices for grading glioma compared with blood volume information. Furthermore, the correlation between tumor blood volume and the amount of choline was statistically significant. Conclusion MRS may provide valuable information for glioma grading.

The purpose of our study was to determine whether (18)F-FDG PET can be used to differentiate among common enhancing brain tumors such as lymphoma, high-grade glioma, and metastatic brain tumor.We evaluated 34 patients with an enhancing brain tumor on MRI, including seven lymphomas, nine high-grade gliomas, and 18 metastatic tumors. All patients also underwent FDG PET. For PET image analysis, regions of interest were placed over the tumor (T), contralateral cortex (C), and white matter (WM). Average and maximum pixel values were determined at each site. On the basis of these measurements, average and maximum standard uptake values (SUV(avg) and SUV(max)) were calculated, along with activity ratios (T/C(avg), T/WM(avg), T/WM(max), and T/C(max)), and comparisons among lesions were then made.All parameters were significantly higher for lymphoma than for other tumors (p0.01). High-grade gliomas showed significantly higher SUV(avg) and SUV(max) than metastatic tumors (p0.05). Other parameters did not differ between lesion types. SUV(max) was the most accurate parameter for distinguishing lymphomas. Using an SUV(max) of 15.0 as a cutoff for diagnosing CNS lymphoma, only one high-grade glioma was found as a false-positive (SUV(max), 18.8).FDG PET may be useful for differentiating common enhancing malignant brain tumors, particularly lymphoma versus high-grade glioma and metastatic tumor. FDG PET can provide useful information for distinguishing between lymphoma and other malignant enhancing brain tumors and is recommended when differential diagnoses are difficult to narrow using MRI alone.

Purpose To clarify the components primarily responsible for diffusion abnormalities in pancreatic cancerous tissue. Materials and Methods Subjects comprised 10 patients with surgically confirmed pancreatic cancer. Diffusion-weighted (DW) echo-planar imaging (b value = 0, 500 s/mm2) was employed to calculate the apparent diffusion coefficient (ADC). ADC values of cancer and noncancerous tissue were calculated. Furthermore, ADC values of the cancer were compared with histopathological results. Results The mean (±standard deviation) ADC value was significantly lower for tumor (1.27 ± 0.52 × 10−3 mm2/s) than for noncancerous tissue (1.90 ± 0.41 × 10−3 mm2/s, P < 0.05). Histopathological examination showed similar proportions of fibrotic area, cellular component, necrosis, and mucin in each case. Regarding the density of fibrosis in cancer, three cases were classified in the loose fibrosis group and the remaining seven cases were classified in the dense fibrosis group. The mean ADC value was significantly higher in the loose fibrosis group (1.88 ± 0.39 × 10−3 mm2/s) than in the dense fibrosis group (1.01 ± 0.29 × 10−3 mm2/s, P < 0.05). In quantitative analysis, ADC correlated well with the proportion of collagenous fibers (r = −0.87, P < 0.05). Conclusion Collagenous fibers may be responsible for diffusion abnormalities in pancreatic cancer. J. Magn. Reson. Imaging 2008;27:1302–1308. © 2008 Wiley-Liss, Inc.

Hematuria is a commonly encountered symptom of a wide spectrum of diseases, including calculi, tumors, and vascular abnormalities. In rare cases, hematuria is caused by life-threatening vascular diseases. When hematuria is encountered, physicians sometimes fail to include vascular diseases in the differential diagnosis because of their rare association with hematuria. Likewise, radiologists often fail to do so because of the low frequency of occurrence of these diseases. Multidetector computed tomography performed with the bolus injection technique should be the first-line diagnostic test when vascular disease is suspected. Radiologists should be familiar with the various imaging findings of hematuria caused by vascular disease. They should also be familiar with the management options (including endovascular techniques) for hematuria caused by vascular disease, since in some cases affected patients can be treated with interventional procedures.

The purpose of this study was to suppress CSF flow artifacts in the fast FLAIR sequence at 3.0T MRI. We investigated the influence of thickness of the inversion pulse in the sequence on the high-intensity CSF flow artifacts based on the flow phantom and in-vivo studies at 1.5T and 3.0T. Results demonstrated that CSF flow artifacts at 3.0T were clearly stronger than at as 1.5T. Moreover, 3.0T was influenced by the crosstalk between each inversion pulse compared with 1.5T. The optimal setting of inversion pulse for two interleaving acquisitions for fast FLAIR imaging at 3.0T was approximately 1.5 fold on the basis of sum of slice thickness and slice gap. The appropriate setting of thickness of inversion pulse in fast FLAIR imaging reduces the incidence of CSF flow artifacts at 3.0T.

Purpose: To propose a simple and useful method for correcting nonuniformity of high-field (3 Tesla) T1-weighted spin-echo (SE) images based on a B1 field map estimated from gradient recalled echo (GRE) signals. Methods: To estimate B1 inhomogeneity, spoiled gradient recalled echo (SPGR) images were collected using a fixed repetition time of 70 ms, flip angles of 45 and 90 degrees, and echo times of 4.8 and 10.4 ms. Selection of flip angles was based on the observation that the relative intensity changes in SPGR signals were very similar among different tissues at larger flip angles than the Ernst angle. Accordingly, spatial irregularity that was observed on a signal ratio map of the SPGR images acquired with these 2 flip angles was ascribed to inhomogeneity of the B1 field. Dual echo time was used to eliminate T2* effects. The ratio map that was acquired was scaled to provide an intensity correction map for SE images. Both phantom and volunteer studies were performed using a 3T magnetic resonance scanner to validate the method. Results: In the phantom study, the uniformity of the T1-weighted SE image improved by 23%. Images of human heads also showed practically sufficient improvement in the image uniformity. Conclusion: The present method improves the image uniformity of high-field T1-weighted SE images.

Small cell glioblastoma (SCGBM) is a variant of glioblastomas characterized by a predominant population of small and monomorphic glial cells. The aim of the present study was to investigate clinical, neuroimaging, pathologic, and genetic features of SCGBM. The clinicopathologic and genetic features were evaluated in 14 patients with SCGBM. All cases were divided into multifocal and solitary type by MRI, and extent of microvascular proliferation, intratumoral necrosis, and perivascular lymphocytic accumulation were investigated. IDH1 mutations by immunohistochemistry (IDH1 R132H) and 1p 19q codeletion by fluorescence in situ hybridization were detected. Patients ranged from 23 to 92 years of age (median: 71 years), with three females and eleven males. The overall survival time of the patients ranged from 7 to 23 months (mean: 11 months). Nine patients (64%) were the multifocal type. Pathologic study revealed that the microvascular proliferation, necrosis, and lymphocytic infiltration were limited in SCGBM. Immunohistochemically, tumor cells were negative for IDH1 R132H in all patients. FISH analysis demonstrated that no SCGBM had 1p/19q codeletion in informative patients. Our investigation suggested that an elderly onset and multifocal lesions were characteristics of SCGBM associated with degradation of the immune response, infiltrative feature of tumor cells, and an unfavorable prognosis.

A 55-year-old woman was referred for a suspicion of mediastinal tumor through plain X-ray photography (X-P). Magnetic resonance imaging (MRI) revealed a 3 cm diameter tumor which seemed to connect to the thyroid and projected into the mediastinum. A fine needle aspiration biopsy was tried but could not reach a conclusive diagnosis. Thereby, fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) was performed and a high accumulation was revealed with standardized uptake value (SUV) of 3.8. Thus, the right lobe excision procedure was enforced. The obtained tumor was continuous to the right lobe as expected. Microscopically, the encapsulated tumor consisted of atypical large-sized follicles without malignant characteristics. Thus, histological diagnosis was follicular thyroid adenoma. Thus, follicular adenoma of thyroid could present negative iodine-123-radioisotope (123I-RI) uptake and positive 18F-FDG-PET accumulation.

Background Metastasis to the pituitary gland is extremely rare and is often detected incidentally by symptoms associated with endocrine dysfunction. Breast and lung cancer are the most common primary metastasizing to pituitary gland. Metastasis from hepatocellular carcinoma to the pituitary gland is extremely rare, with only 10 cases having been previously reported. We present here the first case of pituitary metastasis of hepatocellular carcinoma presenting with panhypopituitarism diagnosed by magnetic resonance imaging. Case presentation We report the case of an 80-year-old Japanese woman who presented with the sudden onset of hypotension and bradycardia after having previously been diagnosed with hepatocellular carcinoma. Based on low levels of pituitary hormones, she was diagnosed with panhypopituitarism caused by metastasis of the hepatocellular carcinoma to the pituitary gland. Magnetic resonance imaging with arterial spin-labeling was effective in the differential diagnosis of the intrasellar tumor. The patient died despite hormone replacement therapy because of hypovolemic shock. Conclusion Metastasis to the pituitary gland causes various non-specific symptoms, so it is difficult to diagnose. The present case emphasizes the importance of diagnostic imaging in identifying these metastases. Clinicians should consider the possibility of pituitary metastasis in patients with malignant tumors who demonstrate hypopituitarism.

Purpose Tumor redox is an important factor for cancer progression, resistance to treatments, and a poor prognosis. The aim of the present study was to define tumor redox (over-reduction) using 62Cu-diacetyl-bis(N4-methylthiosemicarbazone) (62Cu-ATSM) PET and compare its prognostic potential in head and neck cancer (HNC) with that of 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG). Methods Thirty HNC patients (stage II–IV) underwent pretreatment 62Cu-ATSM and 18F-FDG PET scans. Maximum standardized uptake values (SUVATSM and SUVFDG) and tumor-to-muscle activity concentration ratios (TMRATSM and TMRFDG) were measured. Reductive-tumor-volume (RTV) was then determined at four thresholds (40%, 50%, 60%, and 70% SUVATSM), and total-lesion-reduction (TLR) was calculated as the product of the mean SUV and RTV for 62Cu-ATSM. In 18F-FDG, metabolic-tumor-volume (MTV) and total-lesion-glycolysis (TLG) were obtained at a threshold of 40%. A ROC analysis was performed to determine % thresholds for RTV and TLR showing the best predictive performance, and these were then used to determine the optimal cut-off values to stratify patients for each parameter. Progression-free-survival (PFS) and cause-specific-survival (CSS) were evaluated by the Kaplan-Meier method. Results The means ± standard deviations of PFS and CSS periods were 16.4±13.4 and 19.2±12.4 months, respectively. A ROC analysis determined that the 70% SUVATSM threshold for RTV and TLR was the best for predicting disease progression and cancer death. Optimal cut-offs for each index were SUVATSM = 3.6, SUVFDG = 7.9, TMRATSM = 3.2, TMRFDG = 5.6, RTV = 2.9, MTV = 8.1, TLR = 14.0, and TLG = 36.5. When the cut-offs for TMRATSM and TLR were set as described above in 62Cu-ATSM PET, patients with higher TMRATSM (p = 0.03) and greater TLR (p = 0.02) showed significantly worse PFS, while patients with greater TLR had significantly worse CSS (p = 0.02). Only MTV in 18F-FDG PET predicted differences in PSF and CSS (p = 0.03 and p = 0.03, respectively). Conclusion Tumor redox parameters measured by 62Cu-ATSM PET may be determinants of HNC patient outcomes and help define optimal patient-specific treatments.

Iliac artery-ureteral fistula (IAUF) is a rare entity that has a potential risk of life-threatening hemorrhage. It is difficult to diagnose and treat appropriately. Conventional treatment for the disease consists of surgical ligation and vascular reconstruction or coil embolization. Surgical treatment is usually difficult for patients with several risk factors. In recent years, endovascular stent-graft treatment for iliac artery pseudoaneurysm has been reported. The present report describes two cases in which endovascular covered stent-graft treatment was successfully applied to treat IAUF, with good clinical outcomes.

PURPOSE: To prospectively assess the usefulness of magnetic resonance (MR) spectroscopy data acquired before the initiation of medical therapy in predicting prognosis in patients with depressive psychosis. MATERIALS AND METHODS: All subjects gave written informed consent to an institutional committee for clinical research-approved study protocol. The clinical course after medication in 52 patients with depressive psychosis (age range, 52-78 years; 21 men, 31 women) was investigated. In all patients, MR spectroscopy was performed with a 1.5-T MR imaging unit before the initiation of medical therapy. Cerebrovascular lesions (CVLs), which appear as high-signal-intensity areas on T2-weighted MR images, were evaluated by using the Fazekas rating scale. Patients were classified into two groups on the basis of the ratio of N-acetylaspartate (NAA) to creatine and phosphocreatine (Cr): Patients in group A had an NAA/Cr ratio greater than 1.91, and patients in group B had an NAA/Cr ratio of 1.91 or less. To assess the response of the patients to medication, standard psychiatric tests--the Verbal Associative Fluency Test (VAFT), the Digit Symbol Test (DST), the Mini-Mental State Examination (MMSE), and the Hamilton Depression Rating Scale (HAM-D)--were administered before and after medical therapy was initiated. Mean test scores before and after medication were compared with paired t testing. P < .05 was considered to indicate a significant difference. RESULTS: There were 25 patients in group A and 27 in group B. In group A, the mean VAFT and DST scores increased and the mean HAM-D score decreased after medication. There was no significant difference in mean MMSE scores before and after medication (P = .945 for group A and P = .934 for group B). In group B, there were no significant differences in any of the psychiatric test scores before and after medication. The high-signal-intensity area score in group B was significantly higher than that in group A (P = .004). CONCLUSION: MR spectroscopy data obtained before the initiation of medical therapy were useful in predicting prognosis in patients with depressive psychosis; this suggests that the combined burden of all CVLs may affect the response to antidepressant medication.

A 3 years old female patient underwent resection and chemotherapy for a yolk sac tumor of the retroperitoneum. Two years later, fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) showed high uptake in the right ischiopubic synchondrosis (IPS), which had a radiolucent structure on CT. The structure showed contrast enhancement on magnetic resonance imaging (MRI), which was a non-specific finding. Six weeks later, a follow-up (18)F-FDG PET/CT scan was performed which showed no abnormal uptake in the IPS. The disappearance of (18)F-FDG uptake preceded that of contrast enhancement on MRI, which was seen 7 months after the initial (18)F-FDG PET/CT scan.This is the first report showing serial changes of (18)F-FDG uptake in IPS, in comparison to MRI findings.

For improvement of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) image quality in the neck, fat-subtracted MRA by use of the two-point Dixon technique was compared with conventional fat-suppressed MRA techniques. Three different types of neck 3D-TOF-MRA were obtained [minimum echo time (TE) (1.9 ms), opposed-phase TE (3.4 ms), and chemical shift selective fat suppression (CHESS) (TE = 1.9 ms)] on five volunteers at 3.0 T. MRA was obtained with subtraction of fat-only images (produced by a two-point Dixon sequence) from minimum-TE MRA images, and compared with other fat-suppressed MRA images. Fat-subtracted MRA demonstrated uniform fat suppression compared with other techniques. The mean vessel-to-fat contrast in fat-subtracted MRA was significantly higher (p

The development of arterial spin labeling (ASL) techniques has provided a useful strategy for quantitative measurement of cerebral blood flow (CBF). However, quantification of transit time has historically been difficult to achieve without prolonged scan times, since ASL has suffered from low signal-to-noise ratio (SNR). Continuous ASL (CASL) has recently been implemented on the 3T magnetic resonance (MR) system, which can provide a more favorable perfusion signal SNR because of the higher Lamor frequency and prolonged T1 times. Therefore, the goal of the present study was to determine whether CASL perfusion imaging on the 3T MR system could evaluate transit time within a reasonable scan time. This study describes a theoretical framework for measuring arterial transit time using a two-compartment model, followed by application of the model to CASL perfusion data obtained from six normal subjects. CBF and arterial arrival time maps were successfully created using a two-parameter fitting procedure, and the transit time obtained with this model was consistent with those obtained from previous reports. However, the CBF values calculated with the present model were lower than those reported when using 1.5T. Possible reasons for this discrepancy, including transit time, CBV, label efficiency and MT effect, are discussed.