Neurosurgery最新文献

Background and objectives: Improved imaging modalities have led to an increased detection of intracranial aneurysms, many of which are small. There is uncertainty in the appropriate management of tiny aneurysms. The objective of this study was to use a large, multi-institutional NeuroVascular Quality Initiative-Quality Outcomes Database (NVQI-QOD) to assess the frequency, safety, and efficacy of treatment of tiny, unruptured middle cerebral artery (MCA) aneurysms.

Methods: The NeuroVascular Quality Initiative-Quality Outcomes Database registry was queried for patients with tiny unruptured MCA aneurysms who underwent treatment. Tiny size was defined as an aneurysm with a maximum dimension of ≤3 mm. Demographics, aneurysm characteristics, and treatment safety were queried. Outcomes included modified Rankin Score (mRS) at discharge and the last follow-up as well as aneurysm occlusion status at discharge.

Results: Of 674 treated, unruptured MCA aneurysms, 57 (8.5%) were tiny. The mean aneurysm width was 2.2 mm, and the mean patient age was 55.9 years. Most aneurysms were treated with microsurgery (61.4%, 35/57). The overall intraoperative complication rate was 5.3% (3/57), and the postoperative complication rate was 10.5% (6/57). 10.5% (6/57) of patients were discharged to rehabilitation. At discharge, 42 (87.5%) of the treated aneurysms had complete occlusion. In the subgroup of patients with recorded follow-up data, 48.3% (14/29) had a mRS of 0 at discharge and 46.9% (15/32) had an mRS of 0 at the last follow-up (median follow-up 166 days).

Conclusion: Treatment of tiny, unruptured MCA aneurysms is efficacious but may have a high rate of complications. Physicians should be cautious when deciding to treat tiny, unruptured MCA aneurysms.

Recent advancements in neuroimaging and machine learning have significantly improved our ability to diagnose and categorize isocitrate dehydrogenase (IDH)-wildtype glioblastoma, a disease characterized by notable tumoral heterogeneity, which is crucial for effective treatment. Neuroimaging techniques, such as diffusion tensor imaging and magnetic resonance radiomics, provide noninvasive insights into tumor infiltration patterns and metabolic profiles, aiding in accurate diagnosis and prognostication. Machine learning algorithms further enhance glioblastoma characterization by identifying distinct imaging patterns and features, facilitating precise diagnoses and treatment planning. Integration of these technologies allows for the development of image-based biomarkers, potentially reducing the need for invasive biopsy procedures and enabling personalized therapy targeting specific pro-tumoral signaling pathways and resistance mechanisms. Although significant progress has been made, ongoing innovation is essential to address remaining challenges and further improve these methodologies. Future directions should focus on refining machine learning models, integrating emerging imaging techniques, and elucidating the complex interplay between imaging features and underlying molecular processes. This review highlights the pivotal role of neuroimaging and machine learning in glioblastoma research, offering invaluable noninvasive tools for diagnosis, prognosis prediction, and treatment planning, ultimately improving patient outcomes. These advances in the field promise to usher in a new era in the understanding and classification of IDH-wildtype glioblastoma.

Background and objectives: Over the course of their career, 66% of neurosurgeons will witness someone accidentally dropping a bone flap on the floor during a craniotomy procedure. Although this event is rare, it can have significant consequences for the patient, and little literature is available to guide management of this complication. Our objective was to compare 5 bone flap decontamination protocols for efficacy in reducing bacterial load, with the goal of safely reimplanting the dropped flap.

Methods: Cadaveric human bone flaps were contaminated with common operating room (OR) contaminant bacteria. The bone flaps were then subject to 1 of 5 decontamination protocols: washing in saline, mechanical debridement, washing in antibiotics, washing in alcoholic chlorhexidine antiseptic, and flash decontamination in autoclave. Inoculum from the flaps was then used to grow bacteria in petri dishes, and bacterial load after decontamination was assessed. Some flaps were physically dropped on an OR floor to simulate and evaluate a real-life contamination.

Results: The observed contamination from a flap dropped on an OR floor can be significant (up to 1070 colony-forming units cultured per flap). All protocols tested decreased bacterial load of the bone flaps to different degrees: saline by 95.7%, mechanical debridement by 97.5%, antibiotic bath by 99.5%, alcoholic chlorhexidine by 99.9%, and flash sterilization by 100.0%. Flash sterilization led to significant alterations in the flap's physical appearance.

Conclusion: In the event of the accidental fall of a bone flap, decontamination by rinsing in an alcohol-chlorhexidine solution followed by 3 successive washes in saline seemed to provide the best balance between effectiveness, safety, and complexity of the method.

Background and objectives: The optimal management strategy for pediatric patients with symptomatic moyamoya disease (MMD) is not well established. This systematic review and meta-analysis compares surgical vs conservative management and direct/combined bypass (DB/CB) vs indirect bypass (IB) for pediatric patients with symptomatic MMD.

Methods: MEDLINE and PubMed were searched from inception to March 17, 2024. For analysis of surgical vs conservative treatment, the primary and secondary outcomes were follow-up ischemic stroke and intracranial hemorrhagic events, respectively. For analysis of DB/CB vs IB, the primary outcome was follow-up ischemic stroke, and secondary outcomes included follow-up transient ischemic attack, new or worsened seizures, symptomatic improvement, modified Rankin Scale score ≤2, and Matsushima grade A at the last follow-up.

Results: Twenty-two included studies yielded 1091 patients, with a median follow-up duration of 35.7 months. Regarding surgical vs conservative management, 428 patients were analyzed. Surgical treatment was associated with lower odds of ischemic stroke (odds ratios [OR] = 0.33 [95% CI, 0.11-0.97], P = .04), and intracranial hemorrhagic events tended to be lower with surgery (OR = 0.25 [0.06-1.03], P = .05). Regarding DB/CB techniques vs IB, 875 patients were analyzed. The groups had similar rates of ischemic stroke (OR = 0.79 [0.31-1.97], P = .61), transient ischemic attack (OR = 1.27[0.46-3.55], P = .64), new or worsened seizures (OR = 1.05[0.3-3.65], P = .93), symptomatic improvement (OR = 2.45[0.71-8.45], P = .16), and follow-up modified Rankin Scale ≤2 (OR = 1.21 [0.16-8.85], P = .85). CB was associated with higher Matsushima grade A relative to IB (OR = 3.44 [1.32-9.97], P = .01).

Conclusion: Surgical revascularization yielded more favorable clinical outcomes than conservative management in this meta-analysis. Clinical outcomes were similar between DB/CB vs IB techniques. Surgical flow augmentation, either by DB/CB or IB, seems to benefit pediatric patients with symptomatic MMD.

Background and objectives: Scholarship has been critical to neurosurgery. As grades and board examinations become pass-fail, finding metrics to distinguish applicants coupled with an emphasis on research has led to growth of reported academic output among neurosurgery applicants. We aimed to evaluate applicant factors that associate with an academically productive neurosurgery resident.

Methods: Applicant characteristics were extracted from Electronic Residency Application Service archives from 2 geographically distinct neurosurgical programs for the 2014 to 2015 match cycle. Publications during residency were quantified, and residency careers were examined. Factors associated with residency publications were examined using univariate and multivariate regressions.

Results: A total of 228 United States (US) applicants to neurosurgery were assessed (89% of US neurosurgery applicants), with 173 matching across 93 programs. The average publication number of matched applicants was higher at 6.6 (median: 4, range: 0-43) that of than unmatched applicants (mean: 2.9, median: 1, range: 0-51). A total of 93.1% of publications were substantiated on PubMed review. Matched candidates published 19.3 manuscripts (median: 13, range: 0-120) on average during residency. On univariate analysis, factors associated with higher residency publications included taking a non-degree-granting extra year for research in medical school, consistently high clerkship grades, depth of preresidency research involvement, number of coresidents, program R25 status, and academic output of neurosurgery department leadership. After multivariate correction, the training environment played an outsized role in predicting resident academic output, with program R25 status significantly associated with resident academic output (odds ratio: 1.25, P = .012). Taking an extra research year in medical school approached but was not significant (odds ratio: 1.19, P = .099). Twelve matched international medical school graduates (IMGs) were also assessed (75% of matched IMG neurosurgery applicants). IMGs exhibited higher total publications and conference abstracts than US matched applicants and also published more during residency.

Conclusion: Cultivating an environment that promotes research endeavors is critical for neurosurgical resident academic growth. Preresidency publication number does not predict publication potential during residency.

Background and objectives: Bacterial brain abscesses may have long-term clinical consequences, eg, mental fatigue or epilepsy, but long-term structural consequences to the brain remain underexplored. We asked if brain abscesses damage brain activity long term, if the extent of such damage depends on the size of the abscess, and if the abscess capsule, which is often left in place during neurosurgery, remains a site of inflammation, which could explain long-lasting symptoms in patients with brain abscess.

Methods: 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT), electroencephalography, and MRI were performed 2 days to 9 years after neurosurgery for bacterial brain abscess.

Results: FDG-PET/CT revealed hypometabolism in the neocortex or cerebellum overlying the previous bacterial abscess in 38 of 40 patients. The larger the abscess, the greater was the extent of the subsequent hypometabolism (r = 0.63; p = 3 × 10-5). In 9 patients, the extent of subsequent hypometabolism seemed to coincide with the extent of peri-abscess edema in the acute phase. Follow-up MRI after ≥1 year in 9 patients showed focal tissue loss and gliosis. In 13 patients with abnormal electroencephalography recordings, abnormalities extended beyond the cerebral lobe affected by the abscess, indicating damage to wider brain networks. The abscess capsule had an FDG signal indicating inflammation only during the first week after neurosurgical pus drainage.

Conclusion: The bigger a brain abscess is allowed to grow, the more extensive is the long-term focal reduction in brain activity. This finding emphasizes the need for rapid neurosurgical intervention. The abscess capsule does not display long-lasting inflammation and probably does not explain long-term symptoms after brain abscess.

Background and objectives: The management of World Health Organization (WHO) grade 2 meningiomas is complicated by their diverse clinical behaviors. Stereotactic radiosurgery (SRS) can be an effective management option. Literature on SRS dose selection is limited but suggests that a higher dose is better for tumor control. We characterize the predictors of post-SRS outcomes that can help guide planning and management.

Methods: We reviewed a cohort of consecutive patients with pathologically-proven WHO grade 2 meningiomas who underwent SRS at a single institution between 2011 and 2023.

Results: Ninety-nine patients (median age 62 years) underwent SRS, 11 of whom received hypofractionated SRS in 5 fractions. Twenty-two patients had received previous irradiation. The median follow-up was 49 months. The median overall survival was 119 months (95% CI 92-NA) with estimated 5- and 10-year survival of 83% and 27%, respectively. The median progression-free survival (PFS) was 40 months (95% CI 32-62), with 3- and 5-year rates at 54% and 35%, respectively. The median locomarginal PFS was 63 months (95% CI 51.8-NA) with 3- and 5-year rates at 65% and 52%. Nine (9%) patients experienced adverse events, 2 Common Terminology Criteria for Adverse Events grade 3 and 7 grade 2, consisting of worsening neurologic deficit from edema. In the single-session cohort, Ki-67 significantly predicted both overall survival and intracranial PFS. Tumors with Ki-67 >10% had 2.17 times the risk of locomarginal progression compared with Ki-67 ≤10% (P = .018) adjusting for covariates. Sex, prescription dose, tumor volume, and location also predicted tumor control. In tumors with Ki-67 >10%, margin dose ≥14 Gy was associated with significantly better tumor control but not for tumors with Ki-67 ≤10%.

Conclusion: The management of WHO grade 2 meningiomas requires a multimodality approach. This study demonstrates the value of a targeted SRS approach in patients with limited disease and further establishes predictive biomarkers that can guide planning through a personalized approach.

Background and objectives: Accredited neurosurgery fellowship training is available in 10 subspecialties and can sometimes be completed during the postgraduate year (PGY)-7 residency year. However, it is not clear whether there are sufficient residency graduates to fill the number of positions available, and residency curriculum structure to support enfolded training is evolving.

Methods: Detailed information about the 117 accredited neurosurgery residency programs and the 282 accredited neurosurgery fellowships was obtained from the Accreditation Council for Graduate Medical Education and Committee on Advanced Subspecialty Training, respectively. Information about residency chief year structure (PGY-6 vs PGY-7) was obtained electronically from each program. An analysis was performed to correlate residency and fellowship training characteristics at each program.

Results: The total number of neurosurgery fellowship positions available per year (352) is much higher than the total number of residency positions (237). Eighty-eight (75%) institutions with a neurosurgery residency offer at least 1 fellowship, and 51 of these have more fellowships than graduating residents. The resident complement at each program correlates with the number of fellowships offered (r2 = .56, P < .05), and the average institutional resident complement where fellowships are offered is greater than 2 per year. Thirty-eight residencies (32%) use a PGY-6 chief model (allowing for enfolded fellowships), and these programs offer significantly more fellowship programs on average than those using a traditional PGY-7 chief model (3.0 vs 2.1, P < .05). For most subspecialties, a minority of fellowships are offered in programs with a PGY-6 chief model.

Conclusion: The number of accredited neurosurgery subspecialty fellowship slots in the United States far exceeds the number of graduating neurosurgery residents. There is no standard for residency curriculum or enfolded fellowships, but smaller programs offer fewer opportunities for subspecialty training. There may be advantages to a uniform approach that standardizes subspecialty training across programs and matches fellowship availability to demand.

Background and objectives: Intracranial hypertension (IH) is associated with an unfavorable outcome in traumatic brain injury (TBI), and management strategies guided by intracranial pressure monitoring improve prognosis. Owing to the limitations of using invasive devices, measurement of optic nerve sheath diameter (ONSD) by ultrasonography is an alternative noninvasive method. However, its accuracy has not been validated in patients with TBI, so we aim to determine the diagnostic accuracy of measuring ONSD by ultrasonography in patients with TBI to estimate IH, compared with invasive monitoring.

Methods: Systematic review of electronic databases and manual literature review from inception to June 2023. The analysis included diagnostic accuracy studies of ultrasonographic measurement of ONSD compared with invasive monitoring published in any language and with patients of any age. A qualitative synthesis was performed describing the clinical and methodological characteristics, strengths, limitations, and quality of evidence. In addition, a bivariate random effects model meta-analysis and a hierarchical summary receiver operating characteristics model were performed for the pediatric and adult population separately.

Results: Five hundred and forty eight patients of 688 in 16 eligible studies were adults and 120 were children. Pooled sensitivity and specificity of ONSD measurement by ultrasonography were 84% (95% CI, 76%-89%) and 83% (95% CI, 73%-90%), respectively. During the sensitivity analysis, these parameters exhibited consistent values. Pooled area under the curve was 0.91 for adults and 0.76 for children. Optimal threshold for estimating IH was 5.76 mm for adults and 5.78 mm for children.

Conclusion: Measurement of ONSD by ultrasonography is a reliable, low-cost, and safe alternative for the estimation of IH with TBI in adults. More robust studies are needed to overcome the high risk of bias and heterogeneity for this analysis.