The cortical high-flow sign in oligodendroglioma, IDH-mutant and 1p/19q-codeleted is correlated with histological cortical vascular densityYamashita, Koji; Murayama, Ryo; Itoyama, Masahiro; Kikuchi, Kazufumi; Kusunoki, Masaoki; Kuga, Daisuke; Hatae, Ryusuke; Fujioka, Yutaka; Otsuji, Ryosuke; Fujita, Nobuhiro; Yoshimoto, Koji; Ishigami, Kousei; Togao, Osamu
doi: 10.1007/s00234-024-03538-1pmid: 39831960
Background and purposeThe cortical high-flow sign has been more commonly reported in oligodendroglioma, IDH-mutant and 1p/19q-codeleted (ODG IDHm-codel) compared to diffuse glioma with IDH-wildtype or astrocytoma, IDH-mutant. Besides tumor types, higher grades of glioma might also contribute to the cortical high flow. Therefore, we investigated whether the histological cortical vascular density or CNS WHO grade was associated with the cortical high-flow sign in patients with ODG IDHm-codel.Materials and methodsThis retrospective study consisted of pathologically confirmed 25 adult patients with ODG IDHm-codel. We implemented pseudo-continuous arterial spin labeling technique with background suppression. Subtraction images were generated from paired control and label images. Tumor-affecting cortices without intense contrast enhancement on conventional MR imaging were targeted for the determination of the cortical high-flow sign. Immunohistochemical staining of CD31 antibody was performed for the identification of vascular endothelial cells. A microscopic field of the most intense vascularization was captured in each specimen. The vessel number and the relative vascular density (%Vessel) were compared between the positive cortical high-flow sign (CHFS+) and the negative cortical high-flow sign (CHFS−) groups using the Mann–Whitney U test. Second, Fisher’s exact test was used to compare the difference between the presence or absence of cortical high-flow sign and CNS WHO grades. Finally, the vessel number and %Vessel were compared between the CNS WHO grade 2 and grade 3 using the Mann–Whitney U test.ResultsThe vessel number and %Vessel were higher in patients with the CHFS+ group than in patients with CHFS− group (p = 0.016 and p = 0.005, respectively). We observed no significant differences (p = 1.00) in the frequency of cortical high-flow sign between the CNS WHO grade 2 and grade 3. In addition, no significant differences are found in the vessel number and %Vessel between the CNS WHO grade 2 and grade 3 (p = 0.121 and p = 0.475, respectively).ConclusionThe cortical high-flow sign on ASL, which is more commonly found in ODG IDHm-codel than in diffuse glioma with IDH-wildtype or astrocytoma, is associated with the histological cortical vascular density in patients with ODG IDHm-codel.
Visualization of cortical neoangiogenesis after combined revascularization surgery in moyamoya disease using silent MRASuzuki, Tomoaki; Hasegawa, Hitoshi; Fujiwara, Hidemoto; Shibuya, Kohei; Okamoto, Kouichirou; Oishi, Makoto
doi: 10.1007/s00234-024-03486-wpmid: 39441413
PurposeTo investigate postsurgical indirect cortical neoangiogenesis in patients with moyamoya disease (MMD) using silent magnetic resonance angiography (MRA).MethodsWe studied 44 patients with MMD (63 hemispheres) who were previously revascularized with combined bypass surgery (23 and 40 hemispheres in pediatric and adult patients, respectively). They underwent follow-up for postoperative bypass patency using time-of-flight (TOF)-MRA and silent MRA between January 2022 and December 2023. The mean duration from surgery to MRA was 8.5 years (range, 1.2–22.3 years). Two observers independently rated the revascularization as follows: 0 (near-complete signal loss or no signal); 1, poor (slightly visible donor arteries); 2, good (acceptable revascularization around the brain surface); and 3, excellent (good quality of revascularization with perfusion from the cortical surface into the middle cerebral artery).ResultsSilent MRA visualized indirect bypass significantly better than TOF-MRA (2.6 ± 0.7 and 1.4 ± 0.8) (P < 0.01). In silent MRA, the mean score of indirect bypass was significantly higher than that of direct bypass (2.6 ± 0.7 and 1.7 ± 1.0; P < 0.01) and indicated good indirect bypass development in both children and adults (91.3% and 85.0%; score ≥ 2). Children exhibited a higher rate of excellent indirect bypass patency than adults (73.9% and 55.0%; score 3). Poor bypass development in indirect bypass (8 hemispheres, mean age: 35.5 ± 17.5 years, mean follow-up period: 11.3 years) was significantly observed in male patients (P < 0.01).ConclusionSilent MRA enables better precision in postsurgical visualization of indirect cortical neoangiogenesis during long-term follow-up and reveals indirect bypass development even in adult patients.
Dual-energy CT angiography in detecting underlying causes of intracerebral hemorrhage: an observational cohort studyPeeters, Michaël T. J.; Postma, Alida A.; van Oostenbrugge, Robert J.; Henneman, Wouter J.P.; Staals, Julie
doi: 10.1007/s00234-024-03473-1pmid: 39453445
BackgroundCT angiography (CTA) is often used to detect underlying causes of acute intracerebral hemorrhage (ICH). Dual-energy CT (DECT) is able to distinguish materials with similar attenuation but different compositions, such as hemorrhage and contrast. We aimed to evaluate the diagnostic yield of DECT angiography (DECTA), compared to conventional CTA in detecting underlying ICH causes.MethodsAll non-traumatic ICH patients who underwent DECTA (both arterial as well as delayed venous phase) at our center between January 2014 and February 2020 were analyzed. Conventional CTA acquisitions were reconstructed (‘merged’) from DECTA data. Structural ICH causes were assessed on both reconstructed conventional CTA and DECTA. The final diagnosis was based on all available diagnostic and clinical findings during one-year follow up.ResultsOf 206 included ICH patients, 30 (14.6%) had an underlying cause as final diagnosis. Conventional CTA showed a cause in 24 patients (11.7%), DECTA in 32 (15.5%). Both false positive and false negative findings occurred more frequently on conventional CTA. DECTA detected neoplastic ICH in all seven patients with a definite neoplastic ICH diagnosis, whereas conventional CTA only detected four of these cases. Both developmental venous anomalies (DVA) and cerebral venous sinus thrombosis (CVST) were more frequently seen on DECTA. Arteriovenous malformations and aneurysms were detected equally on both imaging modalities.ConclusionsPerforming DECTA at clinical presentation of ICH may be of additional diagnostic value in the early detection of underlying causes, especially neoplasms, CVST and DVAs.
Artificial intelligence-assisted volume isotropic simultaneous interleaved bright- and black-blood examination for brain metastasesKikuchi, Kazufumi; Togao, Osamu; Kikuchi, Yoshitomo; Yamashita, Koji; Momosaka, Daichi; Fukasawa, Kazunori; Nishimura, Shunsuke; Toyoda, Hiroyuki; Obara, Makoto; Hiwatashi, Akio; Ishigami, Kousei
doi: 10.1007/s00234-024-03454-4pmid: 39172167
PurposeTo verify the effectiveness of artificial intelligence-assisted volume isotropic simultaneous interleaved bright-/black-blood examination (AI-VISIBLE) for detecting brain metastases.MethodsThis retrospective study was approved by our institutional review board and the requirement for written informed consent was waived. Forty patients were included: 20 patients with and without brain metastases each. Seven independent observers (three radiology residents and four neuroradiologists) participated in two reading sessions: in the first, brain metastases were detected using VISIBLE only; in the second, the results of the first session were comprehensively evaluated by adding AI-VISIBLE information. Sensitivity, diagnostic performance, and false positives/case were evaluated. Diagnostic performance was assessed using a figure-of-merit (FOM). Sensitivity and false positives/case were evaluated using McNemar and paired t-tests, respectively.ResultsThe McNemar test revealed a significant difference between VISIBLE with/without AI information (P < 0.0001). Significantly higher sensitivity (94.9 ± 1.7% vs. 88.3 ± 5.1%, P = 0.0028) and FOM (0.983 ± 0.009 vs. 0.972 ± 0.013, P = 0.0063) were achieved using VISIBLE with AI information vs. without. No significant difference was observed in false positives/case with and without AI information (0.23 ± 0.19 vs. 0.18 ± 0.15, P = 0.250). AI-assisted results of radiology residents became comparable to results of neuroradiologists (sensitivity, FOM: 85.9 ± 3.4% vs. 90.0 ± 5.9%, 0.969 ± 0.016 vs. 0.974 ± 0.012 without AI information; 94.8 ± 1.3% vs. 95.0 ± 2.1%, 0.977 ± 0.010 vs. 0.988 ± 0.005 with AI information, respectively).ConclusionAI-VISIBLE improved the sensitivity and performance for diagnosing brain metastases.
Alteration of dynamical degree centrality in brain functional network and its association with metabolic disorder in minimal hepatic encephalopathyHuang, Hui-Wei; Liu, Rong-Hua; Zeng, Jing-Yi; Li, Dan; Li, Jian-Qi; Chen, Hua-Jun
doi: 10.1007/s00234-024-03470-4pmid: 39352413
PurposeTo investigate dynamical degree centrality (dDC) alteration and its association with metabolic disturbance and cognitive impairment in minimal hepatic encephalopathy (MHE).MethodsFifty-eight cirrhotic patients (22 with MHE, 36 without MHE [NHE]) and 25 healthy controls underwent resting-state functional magnetic resonance imaging, 1H-magnetic resonance spectroscopy, and neurocognitive examination based on the Psychometric Hepatic Encephalopathy Score (PHES). We obtained metabolite ratios in the bilateral posterior cingulate cortex and precuneus, including glutamate and glutamine (Glx)/total creatine (tCr), myo-inositol (mI)/tCr, total choline/tCr, and N-acetyl aspartate/tCr. For each voxel, degree centrality was calculated as the sum of its functional connectivity with other voxels in the brain; and sliding-window correlation was used to calculate dDC per voxel.ResultsWe observed a stepwise increase in Glx/tCr and a decrease in mI/tCr from NHE to MHE. The intergroup dDC differences were observed in the bilateral posterior cingulate cortex and precuneus (region of interest [ROI1]), bilateral superior-medial frontal gyrus and anterior cingulate cortex (ROI2), and left caudate head. The dDC in ROI2 (r = 0.450, P < 0.001) and mI/tCr (r = 0.297, P = 0.024) was correlated with PHES. Significant correlations were found between dDC in ROI1 and Glx/tCr (r = − 0.413, P = 0.001) and mI/tCr (r = 0.554, P < 0.001). The dDC in ROI2, Glx/tCr, and mI/tCr showed potential for distinguishing NHE from MHE (areas under the curve = 0.859, 0.655, and 0.672, respectively).ConclusionOur findings suggested dynamic brain network disorganization in MHE, which was associated with metabolic derangement and neurocognitive impairment.
Reorganization of central auditory pathways in vestibular schwannoma: a diffusion tensor imaging studyPatel, Kautilya R.; Bhagavatula, Indira Devi; Konar, Subhas K.; Kaushal, Shubham; HR, Aravinda
doi: 10.1007/s00234-024-03534-5pmid: 39739033
PurposeObjective information about the central auditory pathways in vestibular schwannoma can guide strategies for hearing rehabilitation and prognostication. This study aims to generate this information using diffusion tensor imaging (DTI).MethodsThis is a prospective observational single center study including 35 patients with vestibular schwannoma and 40 controls. Subjects underwent 64 direction multi-shell DTI which was processed to yield scalar parameters [Fractional Anisotropy (FA) and Apparent Diffusion Coefficient (ADC)] and probabilistic fiber tracking parameters.ResultsFA values were found to be significantly reduced at bilateral medial geniculate bodies and contralateral inferior colliculus (P < 0.001). In contrast, FA values were significantly increased at bilateral Heschl’s gyrus (P < 0.001). This was further validated by a progressive increase in FA values at bilateral Heschl’s gyri with increasing tumor size. Contralateral inferior colliculus showed a marginal increase in FA value (P = 0.006) and a marginal decrease in ADC value (P = 0.045) in patients with nonfunctional hearing as compared to patients with functional hearing. Rest of the DTI parameters were comparable across patient groups based on duration of hearing loss, hearing function, tumor location and tumor size. FA values along the tracts and the tract volumes were reduced significantly on both the sides (P < 0.001).ConclusionVestibular schwannoma induces degenerative changes in subcortical auditory pathways bilaterally; bilateral medial geniculate bodies and contralateral inferior colliculi being the epicenters of these changes. Primary auditory cortex attempts to reorganize and adjust to the loss of these subcortical inputs.