Neuroradiology

Malik, Prateek; Shroff, Manohar

doi: 10.1007/s00234-022-03100-xpmid: 36534135

The central nervous system (CNS) undergoes constant immune surveillance enabled via regionally specialized mechanisms. These include selectively permissive barriers and modifications to interlinked innate and adaptive immune systems that detect and remove an inciting trigger. The end-points of brain injury and edema from these triggers are varied but often follow recognizable patterns due to shared underlying immune drivers. Imaging provides insights to understanding these patterns that often arise from unique interplays of infection, inflammation and genetics. We review the current updates in our understanding of these intersections and through examples of cases from our practice, highlight that infection and inflammation follow diverse yet convergent mechanisms that can challenge the CNS in children.

Tritanon, Oranan; Mataeng, Suphanika; Apirakkan, Mungkorn; Panyaping, Theeraphol

doi: 10.1007/s00234-022-03093-7pmid: 36456894

PurposeDifferentiating between atherosclerosis, vasculitis, and dissection is a diagnostic challenge because of inconclusive findings on conventional imaging and some overlap in the vessel wall patterns. The aim of this study was to determine whether vessel wall MRI patterns can differentiate between these vasculopathies.MethodsWe retrospectively reviewed 3T high-resolution vessel wall imaging studies of patients diagnosed with atherosclerotic plaques, vasculitis, and dissection. The patterns of involvement, wall enhancement, and T1 and T2 signals, as well as the specific patterns, were assessed and compared between the three diseases.ResultsFifty-nine patients with atherosclerosis (n = 33), vasculitis (n = 13), and dissection (n = 13) were enrolled. There were significant differences in the pattern of involvement between the three groups (P < 0.001), with concentric wall thickening in vasculitis patients (84.6%) and eccentric wall thickening in atherosclerosis (97%) and dissection (92.3%) patients. There was also a significant difference in the specific pattern (P < 0.001), with intimal flap (76.9%) and intramural hematoma (23.1%) in dissection patients and intraplaque hemorrhage (18.2%) in atherosclerosis patients. Furthermore, subgroup analysis showed a significant difference in the wall enhancement pattern between atherosclerosis and vasculitis patients (P < 0.05). Finally, there was a significant difference in the location of involvement between the three groups (P < 0.001).ConclusionBy using the pattern of involvement, wall enhancement, and specific patterns, vessel wall MRI can help differentiate between atherosclerosis, vasculitis, and dissection.

Togao, Osamu; Obara, Makoto; Yamashita, Koji; Kikuchi, Kazufumi; Arimura, Koichi; Nishimura, Ataru; Nakamizo, Akira; Wada, Tatsuhiro; Tokunaga, Chiaki; Mikayama, Ryoji; Yamashita, Yasuo; Hamano, Hiroshi; Van Cauteren, Marc; Ishigami, Kousei;

Zerweck, Leonie; Hauser, Till-Karsten; Roder, Constantin; Blazhenets, Ganna; Khan, Nadia; Ernemann, Ulrike; Meyer, Philipp T.; Klose, Uwe

doi: 10.1007/s00234-022-03088-4pmid: 36434312

PurposePatients with Moyamoya Angiopathy (MMA) require hemodynamic assessment to evaluate the risk of stroke. Hemodynamic evaluation by use of breath-hold-triggered fMRI (bh-fMRI) was proposed as a readily available alternative to the diagnostic standard [15O]water PET. Recent studies suggest voxel-wise hemodynamic delay correction in hypercapnia-triggered fMRI. The aim of this study was to evaluate the effect of delay correction of bh-fMRI in patients with MMA and to compare the results with [15O]water PET.Methodsbh-fMRI data sets of 22 patients with MMA were evaluated without and with voxel-wise delay correction within different shift ranges and compared to the corresponding [15O]water PET data sets. The effects were evaluated combined and in subgroups of data sets with most severely impaired CVR (apparent steal phenomenon), data sets with territorial time delay, and data sets with neither steal phenomenon nor delay between vascular territories.ResultsThe study revealed a high mean cross-correlation (r = 0.79, p < 0.001) between bh-fMRI and [15O]water PET. The correlation was strongly dependent on the choice of the shift range. Overall, no shift range revealed a significantly improved correlation between bh-fMRI and [15O]water PET compared to the correlation without delay correction. Delay correction within shift ranges with positive high high cutoff revealed a lower agreement between bh-fMRI and PET overall and in all subgroups.ConclusionVoxel-wise delay correction, in particular with shift ranges with high cutoff, should be used critically as it can lead to false-negative results in regions with impaired CVR and a lower correlation to the diagnostic standard [15O]water PET.

Park, Jung Hyun; Bae, Yun Jung; Kim, Ji Su; Jung, Woo Sang; Choi, Jin Wook; Roh, Tae Hoon; You, Namkyu; Kim, Se-Hyuk; Han, Miran

doi: 10.1007/s00234-022-03073-xpmid: 36274107

PurposeGlymphatic system dysfunction has been reported in animal models of traumatic brain injury (TBI). This study aimed to evaluate the activity of the human glymphatic system using the non-invasive Diffusion Tensor Image-Analysis aLong the Perivascular Space (DTI-ALPS) method in patients with TBI.MethodsA total of 89 patients with TBI (June 2018 to May 2020) were retrospectively enrolled, and 34 healthy volunteers were included who had no previous medical or neurological disease. Magnetic resonance imaging (MRI) with DTI was performed, and the ALPS index was calculated to evaluate the glymphatic system’s activity. Wilcoxon rank-sum test was used to compare the ALPS index between patients with TBI and healthy controls. ANOVA was done to compare the ALPS index among controls and patients with mild/moderate-to-severe TBI. Multivariate logistic regression analyses were used to identify independent clinical and radiological factors associated with the ALPS index. The correlation between Glasgow Coma Scale (GCS) score and the ALPS index was also assessed.ResultsThe ALPS index was significantly lower in patients with TBI than in healthy controls (median, 1.317 vs. 1.456, P < 0.0001). There were significant differences in the ALPS index between healthy controls and patients with mild/moderate-to-severe TBI (ANOVA, P < 0.001). The presence of subarachnoid hemorrhage (P = 0.004) and diffuse axonal injury (P = 0.001) was correlated with a lower ALPS index in the multivariate analysis. There was a weak positive correlation between the ALPS index and GCS scores (r = 0.242, P = 0.023).ConclusionsThe DTI-ALPS method is useful for evaluating glymphatic system impairment and quantifying its activity in patients with TBI.

Kitazaki, Yuki; Ikawa, Masamichi; Yamaguchi, Tomohisa; Enomoto, Soichi; Shirafuji, Norimichi; Yamamura, Osamu; Tsujikawa, Tetsuya; Okazawa, Hidehiko; Kimura, Hirohiko; Nakamoto, Yasunari; Hamano, Tadanori

doi: 10.1007/s00234-022-03085-7

Chen, Zhengwei; Rong, Liangqun; Xiao, Lijie; Wang, Quan; Liu, Yueji; Lin, Cunxin; Wang, Jianing; Liu, Haiyan; Wei, Xiu-e

doi: 10.1007/s00234-022-03086-6pmid: 36447059

  PurposeTo characterize the altered brain function in patients with vestibular migraine (VM) using resting-state functional magnetic resonance imaging (fMRI).MethodsIn this prospective study, fMRI images as well as clinical characteristics and behavioral scales were collected from 40 VM patients and 40 healthy controls (HC). All patients received neurological, neuro-otological, and conventional MRI examinations to exclude peripheral vestibular lesions, focal lesions, and other neurological diseases. Seed-based (bilateral parietal operculum cortex 2, OP2) functional connectivity (FC) and independent component analysis (ICA)-based functional network connectivity (FNC) were performed to investigate the brain functional changes in patients with VM. Additionally, the correlations between the altered FC/FNC and behavioral results were analyzed.ResultsCompared with HC, patients with VM showed increased FC between the left OP2 and right precuneus and exhibited decreased FC between the left OP2 and left anterior cingulate cortex. We also observed increased FC between the right OP2 and regions of the right middle frontal gyrus and bilateral precuneus, as well as decreased FC between the bilateral OP2. Furthermore, patients with VM showed decreased FNC between visual network (VN) and networks of auditory and default mode, and exhibited increased FNC between VN and executive control network. A correlation analysis found that FC between the left OP2 and right precuneus was positively correlated with scores of dizziness handicap inventory (DHI) in patients with VM.ConclusionThe present study demonstrated altered brain function in patients with VM.

Da Ros, Valerio; Duggento, Andrea; Cavallo, Armando Ugo; Bellini, Luigi; Pitocchi, Francesca; Toschi, Nicola; Mascolo, Alfredo Paolo; Sallustio, Fabrizio; Di Giuliano, Francesca; Diomedi, Marina; Floris, Roberto; Garaci, Francesco; Zeleňák, Kamil; Maestrini, Ilaria

Xu, Xiangjun; Yang, Ke; Xu, Junfeng; Yang, Qian; Guo, Yapeng; Xu, Youqing; Wang, Hao; Ge, Liang; Zhou, Zhiming; Huang, Xianjun

doi: 10.1007/s00234-022-03078-6pmid: 36333556

PurposeThe purpose of this study was to evaluate differences in endovascular treatment (EVT) outcomes in M1 segment middle cerebral artery occlusion (MCAO) patients with different pathologic subtypes.MethodsPatients with MCAO who received EVT from July 2014 to December 2020 were categorized into three groups: embolism without internal carotid artery steno-occlusion (MCAO-E), in situ atherosclerotic thrombosis (MCAO-AS) and embolism from tandem ICA steno-occlusion (MCAO-T). Baseline characteristics, EVT-related factors and clinical outcomes were compared between groups. Multivariable regression analyses were performed to evaluate the relationship between aetiologic classification and outcomes at 90 days after stroke.ResultsAmong eligible patients (n = 220), MCAO-E (n = 129, 58.6%) was the most common aetiology, followed by MCAO-AS (n = 47, 21.4%) and MCAO-T (n = 44, 20.0%). Patients with MCAO-E were significantly older but had a lower rate of dyslipidaemia and smoking history than those with MCAO-AS. Although patients with MCAO-AS and MCAO-T more often required rescue balloon angioplasty and stenting (p < 0.001), no significant difference in the rate of final recanalization was found. Patients in the MCAO-AS group obtained better functional outcomes (90-day modified Rankin Scale score, 0–2) (p = 0.002) and lower mortality than in the MCAO-E group (p = 0.009). On multivariable logistic regression, we failed to find that stroke subtype was an independent predictor of functional outcomes and mortality.ConclusionsPatients with acute MCA M1 occlusion stroke due to different pathogeneses had comparable successful recanalization rates and functional independence at 90 days. The optimal management for MCAO patients with different aetiologies requires further research.

Liu, Lian; Wang, Meiping; Wang, Yuanyuan; Yu, Zequan; Miao, Zhongrong

doi: 10.1007/s00234-022-03090-wpmid: 36409324

PurposeThe aim of this study is to test the prognostic value of a diffusion-weighted imaging (DWI) score in acute basilar artery occlusion (ABAO) with successful recanalization.MethodsThe DWI-based pons-midbrain and thalamus (PMT) score was developed to assess posterior circulation infarcts. We test its prognostic value and compare it with other two established scales, the DWI-based posterior circulation acute stroke prognosis Early CT score (PC-ASPECTS) and brain stem score (BSS). A retrospective cohort of consecutive ABAO patients with pretreatment magnetic resonance imaging and successful recanalization (defined as modified Thrombolysis in Cerebral Infarction 2b-3) were analyzed. A favorable outcome was defined as a 90-day modified Rankin Scale (mRS) score of 2 or less. The prognostic performance of three scales was estimated by receiver operating characteristic (ROC) curve analyses.ResultsOne hundred and sixteen eligible patients (mean age, 59.1 ± 11.7 [standard deviation]; 96 [82.8%] man) were included and evaluated. Between favorable (mRS ≤ 2) and unfavorable groups, the baseline PMT score (median [interquartile range], 3 [1–4] versus 6 [5–8]; P < 0.001) differs significantly. ROC curve analyses showed the PMT score had the best prognostic value for favorable outcome (area under the curve, PMT versus BSS versus PC-ASPECTS = 0.80 versus 0.72 versus 0.68, P = 0.010). Multivariate logistic regression analyses showed baseline National Institute of Health stroke scale (OR, 0.90 [95%CI, 0.86–0.95], P = 0.004) and PMT score < 5 (OR, 17.83 [95%CI, 3.91–81.19], P < 0.001) were independent prognostic factors of favorable outcome.ConclusionsThe PMT score seems to predict clinical outcome of ABAO patients with successful recanalization.