Journal of neurosurgery最新文献

Objective: Volumetric hemodynamic analysis has previously demonstrated robustness to surface irregularities and noise; however, quantitative evaluation methods remain limited. The authors introduce a novel approach to assess intradome velocity distributions in intracranial aneurysms by applying radiomics texture and pattern analysis to time-step data derived from transient computational fluid dynamics (CFD) simulations.

Methods: Angiographic volumes from catheter 3D rotational angiography were available for 75 aneurysms (33 ruptured). Transient CFD simulations were performed on aneurysm models over an entire cardiac cycle. Intradome volumetric velocity distributions were exported for consecutive time points, followed by maximum intensity projection (MIP) to 2D images and logarithmic transformation to enhance discrimination analysis at the intensity extrema. Two-dimensional images representing consecutive time points were used as input to radiomics as 3D DICOM volumes. Univariate and multivariate analyses assessed rupture status discrimination accuracy of 93 histogram, texture, and pattern radiomics features.

Results: Radiomics analysis of MIP velocity texture and pattern revealed that, compared with unruptured aneurysms, ruptured aneurysms have lower intensity patterns (higher energy and total energy of logarithmic values), reflecting dominant low-velocity regions. These regions exhibit consistent intensity textures (higher correlation and inverse difference, with lower cluster shade and difference entropy) with recurrent patterns of similar intensities (higher maximum probability and long-run emphasis). Localized high-velocity runs are also present (higher high gray-level run emphasis) in ruptured aneurysms, suggesting a heterogeneous flow profile. Stepwise regression multivariate analysis achieved rupture status discrimination with an area under the curve of 0.88 (sensitivity 0.91, specificity 0.74).

Conclusions: The automatic analysis of transient velocity using radiomics, incorporating pattern and texture analysis, demonstrated strong discriminating performance for rupture status. This innovative application of radiomics expands its utility beyond tumor and aneurysm shape analysis, enabling evaluation of velocity changes throughout the entire cardiac cycle. It provides valuable insights into rupture characteristics and paves the way for exploring future research possibilities.

Objective: Vertebrobasilar dolichoectatic aneurysms are a rare type of intracranial aneurysm and are generally associated with a poor prognosis due to high rates of morbidity and mortality secondary to ischemic stroke, mass effect, and intracerebral hemorrhage (ICH) or subarachnoid hemorrhage from rupture. When symptomatic, these lesions often mandate treatment. The aim of this study was to explore the most cost-effective management strategy for dolichoectatic aneurysms.

Methods: A decision algorithm was built with a Markov model to compare immediate treatment versus regular follow-up at different intervals (6-month and 1- and 2-year intervals) for dolichoectatic aneurysms. Input data for the model were extracted from the current literature. Costs, effects, incremental cost-effectiveness ratios, and net monetary benefits (NMBs) were analyzed. Deterministic sensitivity analysis and probabilistic sensitivity analysis with Monte Carlo simulation were performed to evaluate the robustness of the model.

Results: On base case analysis, early treatment for dolichoectatic aneurysms, either through open surgery or endovascular procedure, is the most cost-effective strategy (cost $388,946.24, effectiveness 11.0 quality-adjusted life years), showing the highest NMB. The conclusion remains robust in deterministic sensitivity analysis as well as in Monte Carlo simulation with near 97% cost-effectiveness acceptability. When annual risks of stroke, ICH, growth, and rupture are all very low, a strategy of follow-up every 6 months or annually can be considered.

Conclusions: The cost-effectiveness of MR angiography (MRA) surveillance is only observed in scenarios with an annual ischemic risk < 3.3%, with 6-month follow-up MRA being more cost-effective than that at 1- or 2-year intervals. In contrast, preventive treatment consistently offers a higher NMB when risk increases. The risk of treatment based on patient and aneurysm specific factors should also be considered in the decision to treat.

Objective: Brainstem cavernous malformations (BSCMs) are rare neurovascular lesions, and they are especially rare during pregnancy. Pregnancy was not considered in the international consensus on patient-related factors that influence surgical treatment decisions for BSCMs. Therefore, the authors sought to analyze the association between pregnancy and surgical outcomes of BSCMs.

Methods: The authors retrospectively identified women who were pregnant and underwent microsurgical treatment for a BSCM during a period of 37 years. Pregnant women who underwent surgery antepartum were compared with those who underwent surgery postpartum. Demographics, clinical presentation, BSCM characteristics, gestational age, mode of delivery, neurological outcomes, and obstetric and fetal complications were assessed. Primary maternal outcomes were classified as favorable (modified Rankin Scale [mRS] score ≤ 2) or unfavorable (mRS score > 2) and stable, improved, or worse relative to baseline. A systematic review of the literature was also performed to identify all pregnant women with BSCMs who underwent surgical treatment.

Results: The study identified 11 pregnant women with BSCMs. BSCMs were low grade (Lawton grade 0-II) in 7 of 9 (78%) pregnant women and intermediate grade (III-V) in 2 of 9 (22%). Seven of 11 (64%) pregnant women had ≥ 2 bleeds, and 4 of 11 (36%) had 1 bleed. Seven (64%) patients underwent surgery antepartum and 4 (36%) postpartum; all had favorable final and stable or improved outcomes (p > 0.05). Twelve additional pregnant women with BSCMs who underwent surgical treatment were identified in the literature.

Conclusions: Based on these findings, the authors argue that pregnancy poses no additional risk for poor neurological outcome after surgical treatment of BSCM. Surgical treatment decisions for women with BSCMs should include Lawton BSCM grade, number of symptomatic hemorrhages, and presence of severe or progressive neurological deficits rather than pregnancy status.

Objective: Stereotactic radiosurgery (SRS) is a well-established treatment for brain arteriovenous malformations (bAVMs). However, data on radiation-induced neoplasms (RINs) following SRS in patients with bAVMs remain limited. In this study, authors aimed to evaluate the incidence of newly developed intracranial RINs following SRS for bAVMs.

Methods: The authors retrospectively analyzed anonymized data for patients who underwent SRS for bAVMs between 1990 and 2019 at 18 Gamma Knife centers in Japan. Patients with fewer than 3 years of radiological follow-up, prior radiotherapy, or genetic tumor predisposition were excluded. Newly developed tumors were classified as in field (within the 2-Gy isodose line) or out of field. Annual incidence rates were calculated based on total patient-years of follow-up.

Results: During a median radiological follow-up of 100 months, new intracranial tumors developed in 12 (0.27%) of the 4376 patients included in the study. In-field malignant tumors occurred in 5 patients (0.11%), with a median latency of 13.3 years. Out-of-field tumors were observed in 7 patients (0.16%), including malignant (n = 3) and benign (n = 4) neoplasms, with a median latency of 17.4 years. The cumulative incidence of in-field tumors at 10, 15, and 20 years was 0.08%, 0.16%, and 0.16%, respectively. The corresponding incidence of out-of-field tumors was 0.11%, 0.11%, and 0.58%, respectively. In terms of tumor histology, the cumulative incidence of new intracranial brain tumors at 10, 15, and 20 years was 0.15%, 0.24%, and 0.40% for malignant tumors and 0.03%, 0.03%, and 0.34% for nonmalignant tumors, respectively. Across 43,950.3 patient-years of radiological follow-up, the overall annual incidence was 0.027%, increasing from 0.005% within 5 years to 0.046% after 5 years. The annual incidence of in-field tumors was 0.011% (0% within and 0.021% after 5 years) and 0.016% for out-of-field tumors (0.005% within and 0.025% after 5 years). Malignant tumors had an annual incidence of 0.018% (0.005% within and 0.030% after 5 years), whereas benign tumors occurred only out of field with an annual incidence of 0.009% (0% within and 0.017% after 5 years).

Conclusions: The incidence of radiation-induced malignancies after SRS for bAVMs is extremely low but potentially fatal. Although the current risk is acceptable compared to the mortality associated with microsurgical resection, the possibility of late-onset malignancies, especially in younger patients, warrants caution. As more patients are treated and follow-up periods become extended, this risk may increase. Therefore, long-term surveillance is essential for accurately assessing and managing the potential for RINs over time.

Objective: Endovascular therapy (EVT) has proven to be beneficial in patients with acute large-vessel occlusion (LVO) and a large infarct. The authors aimed to investigate the outcomes of EVT across different thrombus burdens indicated by the clot burden score (CBS).

Methods: This is a post hoc analysis of the Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core (ANGEL-ASPECT) trial, which, between October 2, 2020, and May 18, 2022, enrolled patients with acute LVO within 24 hours of symptom onset who had an Alberta Stroke Programme Early Computed Tomography Score (ASPECTS) of 3-5 or 0-2 and an infarct-core volume of 70-100 mL. Patients were divided into 2 groups according to the CBS: 0-6 versus 7-9. The primary outcome was the 90-day modified Rankin Scale score ordinal distribution. Safety outcomes were symptomatic intracranial hemorrhage and 90-day mortality.

Results: This study included 429 patients. Among them, 354 (82.5%) patients had a CBS of 0-6, and 75 (17.5%) had a CBS of 7-9. Compared with medical management, EVT was associated with a significant shift toward a better functional outcome at 90 days in the CBS 0-6 subgroup (generalized OR 1.394, 95% CI 1.120-1.736, p = 0.003). However, no significant treatment effect of EVT was observed in the CBS 7-9 subgroup (common OR 1.155, 95% CI 0.517-2.580, p = 0.725). No interaction effect was found between the 2 CBS subgroups (p for interaction = 0.307).

Conclusions: In patients with LVOs and large infarcts, EVT improves functional outcomes in those with a higher thrombus burden but not in those with a lower burden. The CBS has a potential role in selecting candidates for EVT.

Objective: Skull base tumors are difficult to approach because of their deep location and their entrapment by cranial nerves (CNs), arteries, and veins. CN trajectories can be challenging to describe by conventional MRI when they are deformed by skull base tumors. High-resolution (HR) T2-weighted MRI (T2) has been able to depict normal CN cisternal paths; however, tractography has demonstrated value in CN reconstruction when the nerves are displaced by skull base tumors. In the present study, the authors aimed to compare HR T2 to tractography in the detection of CNs displaced by skull base tumors.

Methods: From a case series of various complex skull base tumors managed between July 2015 and December 2023 in a single department, HR T2 scans were acquired, as were diffusion images with dedicated postprocessing, including distortion correction, region of interest design, probabilistic fiber tracking, and three-plane visualization. The positions of CNs displaced by skull base tumors were then compared between HR T2 and tractography.

Results: A total of 132 patients were included in the study. They presented with various skull base tumors: vestibular schwannomas (n = 47), cerebellopontine angle (CPA) meningiomas (n = 46), CPA epidermoid cysts (n = 12), cavernous sinus schwannomas (n = 8), cavernous sinus meningiomas (n = 3), and 16 less frequent histological types. A total of 442 CNs were identified as being displaced by skull base tumors. Of these nerves, 236 (53.4%) were identifiable using HR T2, and 358 (81.0%) were successfully reconstructed using tractography (p < 0.001, McNemar test), although not significantly for the abducens nerve, lower nerves, and hypoglossal nerve. Interestingly, the identification rate of the abducens nerve was higher on HR T2 than tractography (43.5% vs 34.8%).

Conclusions: The present study revealed that tractography is more effective in predicting the position of most nerves displaced by skull base tumors, whereas HR T2 can identify the smallest CNs such as the abducens nerve.

Objective: Tentorial dural arteriovenous fistulas (TDAVFs) are uncommon, high-risk intracranial vascular malformations characterized by severe clinical courses. Transarterial embolization (TAE) has been widely recognized as the primary treatment modality. Nevertheless, limited data exist regarding the safety and efficacy of transvenous embolization (TVE). The current study reports a comparative analysis of TAE and TVE in a consecutive TDAVF cohort, providing detailed insights into both clinical and angiographic outcomes.

Methods: A retrospective cohort analysis was conducted on 53 patients with TDAVFs treated at the authors' institution between January 2016 and March 2024. Patients were categorized into TAE and TVE groups based on the specific procedure performed on each individual.

Results: A total of 53 patients who underwent 59 procedures were included in this study. Onyx served as the exclusive liquid embolic agent in all procedures. TVE demonstrated superior immediate complete occlusion rates compared to TAE (92.3% vs 56.8%, p = 0.04), with sustained long-term occlusion at follow-up (100% vs 65.7%, p = 0.04). Complication rates were comparable (15.4% for TVE vs 6.8% for TAE, p = 0.69), with no permanent neurological deficits. Multivariate analysis identified TVE (adjusted OR 0.096, p = 0.048) and fewer feeding arteries (adjusted OR 0.688, p = 0.009) as independent predictors of immediate occlusion.

Conclusions: In TDAVFs characterized by accessible venous routes, TVE exhibits superior angiographic outcomes compared to TAE, while maintaining comparable complication profiles. The wire-loop technique and dual-microcatheter strategy are essential for achieving reliable venous access. Although TAE remains effective for the majority of TDAVFs, TVE may be a promising initial strategy for lesions with favorable venous accessibility.