AJNR. American journal of neuroradiology最新文献

Background and purpose: Prolonged venous transit (PVT+) is a marker of venous outflow; it is defined as the presence or absence of time-to-maximum ≥10 seconds timing in either the superior sagittal sinus or torcula. This novel perfusion imaging-based metric has been associated with higher odds of mortality and lower odds of functional recovery. This study aims to assess the relationship between PVT on admission perfusion imaging and length of hospital stay in large vessel occlusion strokes successfully reperfused with mechanical thrombectomy.

Materials and methods: Acute ischemic stroke patients with large vessel occlusions in the anterior circulation successfully treated with thrombectomy between 01/2017 and 09/2022 were retrospectively reviewed. The primary outcome was length of stay in the hospital due to the acute stroke event. Univariable and forward stepwise multivariable linear regressions were performed for the primary outcome.

Results: Of 109 patients meeting inclusion, median age was 71 (interquartile range [IQR] 62-80) years. Median hospital length of stay was significantly greater in PVT+ patients (9 [IQR 6-18] days) compared to PVT-patients (6 [IQR 4-12] days, p=0.03). In multivariable regression, PVT+ was significantly associated with length of stay, and PVT+ was associated with approximately two additional days of hospital stay compared to PVT-(p=0.03).

Conclusions: In successfully reperfused large vessel occlusion strokes, PVT+ was associated with an additional two days of hospital stay on average compared to PVT-patients, when adjusting for other clinical covariables. This simple, novel imaging metric is robust in correlating with a range of short and long term clinical outcomes.

Abbreviations: VO = venous outflow; Tmax = time-to-maximum; PVT = prolonged venous transit; AIS-LVO = large vessel occlusion ischemic stroke; SSS = superior sagittal sinus; rCBF = relative cerebral blood flow; IQR = interquartile range; VIF = variance inflation factor.

Background and purpose: Rescue stent (RS) is an accepted rescue option after failed mechanical thrombectomy (MT) for acute ischemic stroke due to intracranial atherosclerotic stenosis (ICAS)-related large vessel occlusion (LVO). However, the long-term outcomes (≥ 12 months) of RS have not yet been elucidated.

Materials and methods: We retrospectively analyzed the data of 154 patients with RS for ICAS-related LVO, which were identified from prospectively maintained multicenter database of RS after MT failure, to assess good outcome (mRS 0-2), mortality, stroke recurrence, symptomatic intracranial hemorrhage (SICH) and stent patency.

Results: Among 154 patients, successful recanalization was achieved in 132 (85.7%) after RS. Clinical follow-up was available in 148 patients at 3 months, of whom 126 were followed longer than 12 months. Good outcome was observed in 53.4% (79/148) at 3 months and 53.2% (67/126) at the final assessment among survivors (median [interquartile range (IQR)] months, 33 [13-91]). The overall incidence of mortality was 16.2% (24/148) Mortality occurred in 8.8% (13/148) of patients at 3 months and 8.7% (11/126) thereafter, respectively. Stroke recurrence was 0.7% (1/148) within 3 months and 3.2% (4/126) thereafter. The overall incidence of SICH was 9.5% (14/148). SICH occurred in 8.8% (13/148) within the first 3 months, and in 0.8% (1/126) thereafter. The stented vessel was patent in 81.1% (99/122) at the first follow-up (median [IQR] days, 3 [1-125]) and 96.7% (89/92) at the final follow-up (median [IQR] months, 18 [13-68]).

Conclusions: Patients with RS for ICAS-LVO showed a low stroke recurrence rate in the long term. The long-term patency of rescue stent appears to remain durable, particularly when it remains patent during the initial follow-upABBREVIATIONS: ICAS = intracranial atherosclerotic stenosis; LVO = large vessel occlusion; AIS = acute ischemic stroke; MT = mechanical thrombectomy; RS = rescue stenting; CT = computed tomography; MR = magnetic resonance; MMD = moyamoya disease; Intra-arterial = IA; Intravenous = IV; DAPT = dual antiplatelet therapy.

Erdheim-Chester Disease (ECD) is a rare, multisystem histiocytic disorder characterized by its variable clinical presentations. Central Nervous System (CNS) involvement is observed in approximately half of ECD patients (up to 76% in some series), and often carries a poorer prognosis. While CNS involvement may remain asymptomatic, others may experience a range of neurological symptoms, including cognitive decline, neuropsychiatric disturbances, motor deficits, cranial or peripheral neuropathies, and endocrine abnormalities.Neuroimaging findings in CNS-ECD are diverse, including neurodegeneration manifesting as cerebral or cerebellar volume loss, solitary or multifocal variably enhancing intraparenchymal lesions along the neuroaxis, meningeal infiltration, involvement of the Hypothalamo-pituitary axis, perivascular sheathing or basal ganglia lesions. Other well documented sites of involvement include the craniofacial region, orbits and spine. Awareness of these findings is relevant, not only because of the non-specific nature of these findings, but also given the high proportion of CNS involvement in ECD as well as the higher mortality associated with CNS involvement.This review provides an in-depth overview of the various manifestations of CNS involvement in ECD and their imaging features, along with a brief overview of the differential considerations which include other histiocytic and non-histiocytic processes.ABBREVIATIONS: ECD＝Erdheim-Chester Disease; RDD＝Rosai-Dorfman Disease; LCH= Langerhans cell histiocytosis.

Background: Intracranial aneurysms (IAs) are the major cause of subarachnoid hemorrhage. Stent-assisted coiling, especially with the Neuroform Atlas stent (NAS), has proven more effective than coiling alone for treating these aneurysms.

Purpose: To perform a systematic review and meta-analysis to investigate the efficacy and safety of NAS in treating IAs.

Data sources: A comprehensive literature search was conducted on PubMed, Embase, Cochrane CENTRAL library, and clinicaltrials.gov from inception till June 2024.

Study selection: We included studies on ruptured and unruptured IAs treated with the NAS, covering experimental, observational, and case series across all age groups. The aneurysm occlusion rate was assessed using the Raymond-Roy classification (RROC). The modified Rankin Scale (mRS) and adverse events related to stent use were also recorded.

Data analysis: The statistical analysis was conducted on R version 4.3.2 using the packages "meta" and "metasens". We reported our results as proportions with their corresponding confidence intervals (CIs). Meta-regression, leave-one-out and sensitivity analyses were conducted to confirm the robustness of our results.

Data synthesis: A total of 42 studies including 2434 participants with a mean age of 51 to 73 years were included. Among angiographic outcomes, the final RROC 1/RROC 2 was achieved in 95% of the patients, final RROC 1 in 82%, RROC 2 in 12%, and RROC 3 in 5% of the patients. Additionally, 93% of the patients showed mRS grade 0, 5% showed mRS grade 1, 3% showed mRS grade 2, 2% showed mRS grade 3, 0% showed mRS grade 4, 0% showed mRS grade 5, and 1% showed mRS grade 6. All adverse events had a ≤ 5% rate.

Limitations: Due to limited cause-specific data, we were unable to analyse mortality specific to the stent placement and complications. Despite the large number of studies included, comparative studies were still observed to be scarce.

Conclusions: Although the generalizability of our findings is limited, this study demonstrates that NAS is highly effective for treating IAs, with high occlusion rates and a low incidence of adverse events. The stent's performance, supported by comprehensive analysis, highlights its safety and efficacy in managing both ruptured and unruptured aneurysms.

Abbreviations: NAS = Neuroform Atlas stent; IA = Intracranial aneurysm; SAC = stent-assisted coiling.

Background and purpose: To develop a new machine-learning algorithm for fully automatic identification of cerebral arteries and intracranial aneurysms (IAs) based on a manually segmented magnetic resonance imaging with time-of-flight sequences (MRITOF) dataset.

Materials and methods: In this retrospective single-center study, 62 MRI-TOF scans of a total of 73 untreated unruptured IAs were manually color-labelled in 21 classes. A nnUNet architecture was trained on MRI-TOF images. The performance of the automatic segmentation was compared with the manual segmentation using Dice Similarity Coefficient (DSC), Centerline Dice (ClDice) and 95th percentile Hausdorff Distance (HD95). Sensitivity was computed for aneurysm detection.

Results: Across all 21 classes, the median DSC was 0.86 [95CI: 0.81, 0.89], the median ClDice 0.91 [0.85, 0.94] and the median HD95 was 2.9 [1.0, 14.9] mm. Sensitivity of the model for aneurysms detection was 0.8. For this class specifically, a median DSC of 0.88 [0.13, 0.92], median ClDice of 0.89 [0.06, 1.0] and median HD95 of 1.8 [0.58, 81] mm was achieved. The volume of the labelled anatomical structure was the most relevant determinant of accuracy in this model. Median time to predict was 130.6 [60.9, 284.1] seconds.

Conclusions: The nnUNet MRI-TOF based algorithm provided a fast and adequate automatic extraction of unruptured intracranial aneurysms, their parent vessels and the most relevant cerebral arteries. Future steps involve the expansion of the training set with the inclusion of more MRI-TOF studies with and without IAs and its incorporation in 3D imaging viewers and treatment prediction.

Abbreviations: IA = Intracranial Aneurysm; MRI-TOF＝ Magnetic Resonance Imaging - Time of Flight; DSC = Dice-Sørenson Coefficient; ClDice = Centerline Dice; HD95 = 95^th Percentile Hausdorff Distance.

Background and purpose: Patterns of the cerebral microcirculatory response with changes in the blood brain barrier and perfusion in patients with stroke and a large vessel occlusion are still unclear. We combined dynamic contrast enhancement (DCE) permeability and DSC perfusion MRI to detect such patterns beyond the borders of the diffusion-restricted infarct core after successful recanalization.

Materials and methods: Combined DCE permeability and DSC perfusion MRI were performed prospectively in patients within 24h after successful mechanical recanalization of acute middle cerebral artery occlusion. Perfusion alterations were visually assessed on CBF and CBV maps, blood-brain-barrier disruptions (BBBD) on ktrans-maps and quantitatively evaluated with an ipsi-to contralateral ratio. Additionally, logistic regression analysis was performed for favorable early clinical outcome (NIHSS ≤2 at discharge).

Results: N=38 patients were included in the study. Subtle hyperperfusion beyond the DWI-lesion was present in 13/38 patients (34%) on CBF-maps and elevated CBV in 15/38 patients (39%). In these patients, the ratios between ipsi-and contralateral white matter CBF (p=0.01) and CBV (p<0.01) were elevated compared to patients with normal readings. Subtle, but visually and quantitatively elevated ktrans-values outside the DWI-lesion were observed in 7/38 patients (18%). None of these perfusion alterations were related to clinical outcome.

Conclusions: Combined DCE-permeability and DSC-perfusion imaging is feasible in patients 24 hours after successful thrombectomy and reveals subtle hyperperfusion and BBBD occuring frequently beyond the diffusion restricted infarct core.

Abbreviations: DCE = Dynamic Contrast Enhancement, BBBD = blood brain barrier disruption, MT = Mechanical thrombectomy.

Background and purpose: Enhancement of the facial nerve can be seen on magnetic resonance imaging (MRI) due to its rich arteriovenous plexus. Classically, enhancement of the facial nerve beyond the geniculate ganglion has been described as a normal finding, while enhancement of the canalicular and labyrinthine segments is considered abnormal. We hypothesize facial nerve enhancement of the canalicular and labyrinthine segments is a normal finding on the post-contrast T-weighted, fat-saturated VIBE (volumetric interpolated breath-hold examination) sequence on both 1.5T and 3T scanners.

Materials and methods: Fifty patients without facial nerve symptoms undergoing MRI using the internal auditory canal (IAC) protocol were identified at our institution, 25 cases on a 1.5T scanner and 25 cases on a 3T scanner; a total of 100 facial nerves. Presence or absence of enhancement of the facial nerve segments on the postcontrast T1-weighted, fat-saturated VIBE sequence were independently analyzed by two neuroradiologists.

Results: On 1.5T, out of 50 facial nerves evaluated, percentage of nerves with enhancement at each segment was as follows: 80% canalicular, 92% labyrinthine, 100% tympanic, 100% mastoid, and 80% intraparotid. On 3T, out of 50 facial nerves evaluated, percentage of nerves with enhancement at each segment was as follows: 60% canalicular, 84% labyrinthine, 98% tympanic, 100% mastoid, and 93% intraparotid.

Conclusions: Enhancement of the canalicular and labyrinthine segments of the facial nerve is a normal finding on the postcontrast, T1-weighted fat-saturated VIBE sequence. Careful attention to clinical history and asymmetry should be considered before calling abnormality of the facial nerve.

Abbreviations: IAC, Internal auditory canal; VIBE, Volumetric interpolated breath-hold examination.

Physician-industry financial relationships can drive research and innovation, improving patient care and outcomes, but potentially raise ethical concerns if not disclosed appropriately. This study shows high rates of non-disclosures by authors/presenters at the ASNR 2024 annual meeting, despite strict requirements. 86.4% of presenters/authors with records in OPD failed to disclose any financial relationship, and 89.9% of total industry payment value was not disclosed. Greater awareness should help improve disclosures and transparency, reducing the risk and perception of bias.ABBREVIATIONS: OPD＝ open payments database; ASNR＝ American Society of Neuroradiology.

Background : Pretreatment CTA-based Cortical Vein Opacification Score (COVES) has been shown to predict good functional outcomes at 90 days in patients with acute ischemic stroke secondary to large vessel occlusion (AIS-LVO). This is thought to be related to its ability to measure collateral status (CS). However, its association with the reference standard test, the DSA-based American Society of Interventional and Therapeutic Neuroradiology (ASITN) collateral score, has yet to be established. Therefore, this study assesses the relationship between COVES and ASITN CS.Methods : In this prospectively collected, retrospectively reviewed analysis, patients with anterior circulation LVO from September 1, 2017, to October 1, 2023, were included. The COVES grading, which ranges from 0 to 6, was independently assessed by two board-certified neuroradiologists. The ASITN CS was independently assessed by a board-certified neuroradiologist and the performing neurointerventionalist. Any discrepancies were resolved through consensus review. Spearman's rank correlation, univariable logistic regression, multivariable logistic regression, and receiver operating characteristic curve analysis were performed. A p-value of ≤0.05 was considered significant.Results : In total, 311 consecutive patients (median, IQR=68 years [59-78 years]; 55.9% female) met our inclusion criteria. There was significant positive correlation between COVES and ASITN CS (ρ=0.41,p<0.001), and higher COVES was significantly and independently associated with good ASITN CS (unadjusted-OR=1.74,p<0.001) and adjusted-OR=1.73, p<0.001). ROC analysis showed AUC of 0.71, p<0.001).Conclusion : In conclusion, by demonstrating the independent association of COVES with the reference standard test for collateral status assessment, the ASITN CS, we further validate the role of COVES in estimating collateral status.ABBREVIATIONS: AIS: Acute ischemic stroke; ASITN: American Society of Interventional and Therapeutic Neuroradiology; CS: Collateral status; COVES: Cortical Vein Opacification Score; HIR: Hypoperfusion Intensity Ratio; IVT: Intravenous thrombolysis; LVO: Large vessel occlusion; mRS: modified Rankin score; MT: mechanical thrombectomy; OR: odds ratio; aOR: adjusted odds ratio; ua: unadjusted odds ratio; rCBF: relative cerebral blood flow; Tmax: Time-to-Maximum.

Background and purpose: Neoadjuvant BRAF-directed therapy and immunotherapy followed by surgery improves survival in patients with BRAF^V600E-mutant anaplastic thyroid carcinoma (ATC), more so in those who have complete ATC pathologic response. This study assesses the ability of FDG-PET to non-invasively detect residual high-risk pathologies including ATC and poorly differentiated thyroid carcinoma (PDTC) in the preoperative setting.

Materials and methods: This retrospective, single-center study included consecutive BRAF^V600E-mutant ATC patients treated with at least 30 days of neoadjuvant BRAF-directed therapy and who underwent FDG-PET/CT within 30 days prior to surgery. The highest pathologic grade observed for every head and neck lesion resected was recorded. Each lesion on pre-operative PET/CT was retrospectively characterized. The primary endpoint was to contrast the standardized uptake normalized by lean body mass (SULmax) for lesions with residual high-risk (ATC, PDTC) versus low-risk pathologies (papillary thyroid carcinoma, negative). An optimal SULmax threshold was then identified using a ROC analysis, and the ability of this threshold to non-invasively and preoperatively risk-stratify patients by overall survival was then evaluated with a Kaplan-Meier plot.

Results: 30 patients (mean age 66.5±9.0; 17 males) were included in this study, with 94 surgically sampled lesions. Of these lesions, 57 (60.6%) were low-risk (39 negative, 18 papillary thyroid carcinoma) and 37 (39.4%) were high-risk (29 ATC, 8 PDTC). FDG uptake was higher for high-risk compared to low-risk pathologies: median SULmax 5.01 [IQR 2.81 - 10.95] versus 1.29 [IQR 1.06 - 3.1] (P<.001, Mann-Whitney U test). The sensitivity, specificity, and accuracy for detecting high-risk pathologies at the optimal threshold of SULmax ≥ 2.75 were 0.784 [95% CI 0.628-0.886], 0.702 [95% CI 0.573-0.805], and 0.734 [95% CI 0.637-0.813], respectively. Patients with at least 1 high-risk lesion identified with the aforementioned cut-off had a worse prognosis compared to patients without high-risk lesions in the head and neck: median OS for the former group was 259 days and was not attained for the latter (P=.038, log-rank test).

Conclusions: Preoperative FDG-PET non-invasively identifies lesions with residual high-risk pathologies following neoadjuvant BRAF-directed targeted therapy and immunotherapy for BRAF-mutated ATC. FDG-PET avidity may serve as an early prognostic marker which correlates with residual high-risk pathology in BRAF-mutated ATC following neoadjuvant therapy.

Abbreviations: ATC = anaplastic thyroid carcinoma; IQR = interquartile range; OS = overall survival; PDTC = poorly differentiated thyroid carcinoma; PTC = papillary thyroid carcinoma; ROC = receiver operating characteristic; SUL= standardized uptake value normalized by lean body mass.