Grading Meningioma : A Comparative Study of Thallium-SPECT and FDG-PET

The purpose was to compare capability of fluorine-18 fluorodeoxyglucose (FDG)-PET and thallium-201 (Tl)-SPECT for grading meningioma. This retrospective study was conducted as a case-control study under approval by the institutional review board. In the hospital information system, 67 patients (22 men and 45 women) who had both FDG-PET and Tl-SPECT preoperative examinations were found with histopathologic diagnosis of meningioma. The maximum FDG uptake values of the tumors were measured, and they were standardized to the whole body (SUVmax) and normalized as gray matter ratio (SUVRmax). Mean and maximum Tl uptake ratios (TURmean and TURmax, respectively) of the tumors were measured and normalized as ratios to those of the contralateral normal brain. Receiver-operating characteristic curve analyses of the 4 indexes were conducted for differentiation between low- and high-grade meningiomas, and areas under the curves (AUCs) were compared. Correlation coefficients were calculated between these indexes and Ki-67. Fifty-six meningiomas were classified as grade I (low grade), and 11 were grade II or III (high grade). In all 4 indexes, a significant difference was observed between low- and high-grade meningiomas (P<0.05). AUCs were 0.817 (SUVmax), 0.781 (SUVRmax), 0.810 (TURmean), and 0.831 (TURmax), and no significant difference was observed among the indexes. Their sensitivity and specificity were 72.7% to 90.9% and 71.4% to 87.5%, respectively. Correlation of the 4 indexes to Ki-67 was statistically significant, but coefficients were relatively low (0.273-0.355). Tl-SPECT, which can be used at hospitals without a cyclotron or an FDG distribution network, has high diagnostic capability of meningioma grades comparable to FDG-PET

Hot cross bun" sign in multiple system atrophy with predominant cerebellar ataxia: a comparison between proton density-weighted imaging and T2-weighted imaging.

[Objective]: To investigate whether proton density-weighted imaging can detect the "hot cross bun" sign in the pons in multiple system atrophy with predominant cerebellar ataxia significantly better than T2-weighted imaging at 3T. [Methods]: Sixteen consecutive patients with multiple system atrophy with predominant cerebellar ataxia according to the Consensus Criteria were reviewed. Axial unenhanced proton density-weighted imaging and T2-weighted imaging were obtained using a dual-echo fast spin-echo sequence at 3T. Two neuroradiologists independently evaluated visualisation of the abnormal pontine signal using a 4-point visual grade from Grade 0 (no "hot cross bun" sign) to Grade 3 (prominent "hot cross bun" sign on two or more sequential slices). Differences in grade between proton density-weighted imaging and T2-weighted imaging were statistically analysed using the Wilcoxon signed-rank test. [Results]: In 11 patients (69%), a higher grade was given for proton density-weighted imaging than T2-weighted imaging. In 1 patient (6%), grades were the same (Grade 3) on both images. In the remaining 4 patients (25%), signal abnormalities were not detected on either image (Grade 0). The "hot cross bun" sign was thus observed significantly better on proton density-weighted imaging than on T2-weighted imaging (P = 0.001). [Conclusions]: The "hot cross bun" sign considered diagnostic for multiple system atrophy with predominant cerebellar ataxia is significantly better visualised on proton density-weighted imaging than on T2-weighted imaging at 3T

シンケイ カスイタイ ハイガシュ ノ MRI オヨビ CT ショケン ノ ケントウ

京都大学0048新制・課程博士博士(医学)甲第10692号医博第2676号新制||医||851(附属図書館)UT51-2004-G539京都大学大学院医学研究科内科系専攻(主査)教授 福山 秀直, 教授 林 拓二, 教授 平岡 眞寛学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDA

Timing dependence of peripheral pulse-wave-triggered pulsed arterial spin labeling.

Arterial spin labeling (ASL) has been developed into a useful technique that is capable of quantifying noninvasively local cerebral blood flow (CBF) using the water molecules in arterial blood as diffusible tracers. Pulsed ASL (PASL) is more strongly affected than continuous ASL (CASL) by cardiac pulsation, because the tag bolus is shorter than the cardiac cycle in most cases. No reports have yet clarified the effects of multiple cardiac phases on the quantification of CBF in PASL when triggering is used. Fourteen subjects participated in this study. Peripheral pulse-wave-triggered (PPWT)-ASL was performed at various time points at the carotid artery (delay 0 ms, second point, foot, peak and tail) and compared with nontriggered (NT)-ASL. Regions of interest (ROIs) were applied based on the anterior, middle and posterior cerebral artery (ACA, MCA, PCA) territories, and CBFs were compared among different time points and ROIs. PPWT-ASL strongly affects CBF values compared with NT-ASL in ACA and MCA territories, especially when measured at the foot of the carotid artery flow phase. CBF_NT was assumed to lie approximately between the minimum and maximum CBFs, with clear statistical significance in several ROIs at several time points of PPWT-ASL, and CBF_NT was assumed to resemble 'randomly triggered' PPWT-ASL. In conclusion, PPWT-ASL strongly affects CBF values compared with NT-ASL, particularly at the foot of the carotid artery flow in ACA and MCA territories

3D dynamic pituitary MR imaging with CAIPIRINHA: initial experience and comparison with 2D dynamic MR imaging.

This work was supported by JSPS KAKENHI grant Number 25461815.Available online 2 July 2014[Objectives]To evaluate the validity of 3D dynamic pituitary MR imaging with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA), with special emphasis on demarcation of pituitary posterior lobe and stalk. [Methods]Participants comprised 32 patients who underwent dynamic pituitary MR imaging due to pituitary or parasellar lesions. 3D dynamic MR with CAIPIRINHA was performed at 3 T with 20-s-interval, precontrast, 1st to 5th dynamic images. Normalized values and enhanced ratios (dynamic postcontrast image values divided by precontrast ones) were compared between 3D and 2D dynamic MR imaging for patients with visual identification of posterior lobe and stalk. [Results]In 3D, stalk was identified in 29 patients and unidentified in 3, and posterior lobe was identified in 28 and unidentified in 4. In 2D, stalk was identified in 26 patients and unidentified in 6 patients, and posterior lobe was identified in 15 and unidentified in 17. Normalized values of pituitary posterior lobe and stalk were higher in 3D than 2D (P < 0.001). No significant difference in enhancement ratio was seen between 3D and 2D. [Conclusions]3D dynamic pituitary MR provided better identification and higher normalized values of pituitary posterior lobe and stalk than 2D

Jugular venous reflux on magnetic resonance angiography and radionuclide venography

Background The relationship between the signal from retrograde venous flow on magnetic resonance angiography (MRA) and retrograde upward flow from the left brachiocephalic vein has not been explored. Purpose To reveal the frequency of jugular venous reflux using MRA and nuclear venography in patients being evaluated for cerebral volume and blood flow. Material and Methods A total of 229 patients with cognitive disturbance who had undergone brain magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) on the same day to evaluate cerebral blood flow were evaluated. Jugular venous reflux was measured on MRA and nuclear venography, which was conducted just after injection of N-isopropyl-123I-p-iodoamphetamine for the SPECT study. Results MRA showed jugular reflux in seven patients on the right side, and in 22 on the left. Nuclear venography showed jugular reflux in six patients on the right side, and in 20 on the left. Conclusion Jugular venous reflux was observed mostly on the left side. Retrograde flow was observed on both MRA and nuclear venography in half of the cases, with the rest only on one of the modalities

Possibility of Interstitial Lung Disease as a Phlebosclerotic Colitis Manifestation

Phlebosclerotic colitis presents with ischemic bowels and calcification of the mesenteric veins. Owing to its rarity, we have little information on the complications of this disease. Herein, we report on a 77-year-old woman with phlebosclerotic colitis and interstitial lung disease. She was diagnosed as having phlebosclerotic colitis by CT and colonoscopy. At the same time, chest CT also showed interstitial lung disease. After 4 years, she experienced exacerbation of interstitial lung disease. She recovered without treatment. The occurrence of interstitial lung disease may have been associated with her phlebosclerotic colitis

Primary central nervous system lymphoma: is absence of intratumoral hemorrhage a characteristic finding on MRI?

Background. Previous studies have shown that intratumoral hemorrhage is a common finding in glioblastoma multiforme, but is rarely observed in primary central nervous system lymphoma. Our aim was to reevaluate whether intratumoral hemorrhage observed on T2-weighted imaging (T2WI) as gross intratumoral hemorrhage and on susceptibilityweighted imaging as intratumoral susceptibility signal can differentiate primary central nervous system lymphoma from glioblastoma multiforme. Patients and methods. A retrospective cohort of brain tumors from August 2008 to March 2013 was searched, and 58 patients (19 with primary central nervous system lymphoma, 39 with glioblastoma multiforme) satisfied the inclusion criteria. Absence of gross intratumoral hemorrhage was examined on T2WI, and an intratumoral susceptibility signal was graded using a 3-point scale on susceptibility-weighted imaging. Results were compared between primary central nervous system lymphoma and glioblastoma multiforme, and values of P < 0.05 were considered significant. Results. Gross intratumoral hemorrhage on T2WI was absent in 15 patients (79%) with primary central nervous system lymphoma and 23 patients (59%) with glioblastoma multiforme. Absence of gross intratumoral hemorrhage could not differentiate between the two disorders (P = 0.20). However, intratumoral susceptibility signal grade 1 or 2 was diagnostic of primary central nervous system lymphoma with 78.9% sensitivity and 66.7% specificity (P < 0.001), irrespective of gross intratumoral hemorrhage. Conclusions. Low intratumoral susceptibility signal grades can differentiate primary central nervous system lymphoma from glioblastoma multiforme. However, specificity in this study was relatively low, and primary central nervous system lymphoma cannot be excluded based solely on the presence of an intratumoral susceptibility signal

Comparison of 3.0- and 1.5-T Three-dimensional Time-of-Flight MR Angiography in Moyamoya Disease: Preliminary Experience

Purpose: To prospectively compare 3.0- and 1.5-T three-dimensional (3D) time-of-flight (TOF) magnetic resonance (MR) angiography in patients with moyamoya disease, with special emphasis on the visualization of abnormal netlike vessels (moyamoya vessels). Materials and Methods: Study protocols were approved by the local ethics committee; written informed consent was obtained from all patients. The study included 24 consecutive patients with moyamoya disease (four male and 20 female patients). Patients ranged in age from 17 to 66 years (mean age, 41 years). Moyamoya disease had been diagnosed in all patients before they were entered into the study. All patients underwent 3D TOF MR angiography at both 3.0 and 1.5 T; imaging examinations were performed within 14 days of each other. Maximum intensity projections (MIPs) obtained with MR angiography performed at both 3.0 and 1.5 T were evaluated by two neuroradiologists; the visualization of moyamoya vessels was graded according to a 4-point scale. For both 3.0- and 1.5-T imaging, the number of high-signal-intensity areas and the summation of cross-sectional areas of high signal intensity on source images obtained at the same level of MR angiography were compared quantitatively by using the Wilcoxon matched-pair signed-rank test. Results: Moyamoya vessels were better visualized on MIPs obtained with 3.0-T imaging than on MIPs obtained with 1.5-T imaging (P < .001). At the identical level of the source image, 3.0-T imaging depicted more high-signal-intensity areas than did 1.5-T imaging. Wider cross-sectional areas of moyamoya vessels were visualized with 3.0-T imaging than with 1.5-T imaging (P < .001). Conclusion: Moyamoya vessels are better depicted with MR angiography at 3.0 T than at 1.5 T