Journal of neurosurgery最新文献

Objective: Due to the unique nature of the basal structures of the cerebrum, only a limited portion is exposed during surgery, leading to potential risk of damage to surrounding structures. The white matter fiber tracts in the basal cerebrum may be more critical than the cortex in determining the extent of resection. A thorough understanding of the 3D anatomy of these fiber tracts is essential for planning safe and precise surgical approaches and provides an anatomical foundation for studying brain function. This study aimed to examine the topographical anatomy of the fiber tracts and subcortical gray matter in the basal cerebrum, as well as their anatomical relationships with the cerebral cortex, ventricles, and associated nuclei.

Methods: Using fiber dissection techniques and magnification ranging from ×6 to ×40, the authors studied 10 formalin-fixed human brains. The study focused on the fiber tracts and subcortical nuclei in the basal cerebrum, including the hippocampus, amygdala, and nucleus accumbens, and their relationships were documented through 3D photography.

Results: The topographical relationships between the commissural, projection, and association fibers and the significant nuclei in the basal cerebrum were identified. Notable landmarks related to the fiber tracts include the cortical gyri and sulci, major basal nuclei, and lateral ventricles. The fiber tracts also exhibited consistent interrelationships.

Conclusions: The 3D microsurgical anatomy of the basal cerebrum provides valuable insights for planning precise and safe surgical approaches and offers anatomical evidence for further studies on brain function.

Objective: Vestibular schwannomas (VSs) are cerebellopontine angle tumors that can result in cranial nerve dysfunction, most commonly sensorineural hearing loss. Conventional structural MRI is unable to provide correlative information on cranial nerve function. In this study, the authors used multitensor tractography to study the white matter microstructural properties of the auditory neural pathway as a correlate of cranial nerve function in a cohort of VS patients. They evaluated the relationship between the auditory neural pathway microstructural properties using pure-tone audiometry (PTA) and the speech discrimination score (SDS).

Methods: Retrospective chart review of 258 patients with VS treated at the Toronto Western Hospital Gamma Knife Radiosurgery Unit was conducted. Of these, 3T MR images were analyzed for 57 surgically naive patients with unilateral VS who had preoperative diffusion tensor imaging (DTI) and PTA and SDS results. Patients were excluded if they had bilateral tumors, previous surgical treatment (Gamma Knife radiosurgery or resection), or did not undergo DTI. DTI-derived metrics (fractional anisotropy [FA], radial diffusivity [RD], axial diffusivity [AD], and mean diffusivity [MD]) of five regions of interest positioned along the auditory neural pathway (ipsilateral superior olivary nucleus [SON] and trapezoid body [TB] and contralateral inferior colliculus, lateral lemniscus [LL], and medial geniculate body [MGB]) were measured bilaterally in all subjects. The diffusion metrics were correlated with quantitative average high-frequency (4000 and 8000 Hz) PTA and SDS results.

Results: Salient areas of neuroanatomical correlation included the LL and SON (affected side), where a statistically significant diffusion metric change was seen. This was characterized by higher FA and lower RD values (LL and SON) and a higher AD value (SON). SDS positively correlated with the TB AD. PTA showed a significant negative relationship with MD at the LL and a positive relationship with AD at the inferior colliculus (affected side). PTA also showed a significant negative relationship with RD and MD at the SON and TB, and a positive relationship with FA and AD at the MGB on the contralateral side (all p < 0.05).

Conclusions: This work outlines that quantitative DTI is a useful tool to evaluate the white matter microstructural alterations in the auditory neural pathway. Importantly, as a noninvasive tool, diffusion metrics can help in understanding the pathophysiology of hearing impairment in this group of patients.

Objective: MR-guided focused ultrasound anterior capsulotomy (MRgFUS-AC) is an incisionless ablative procedure, which has shown reassuring safety and compelling efficacy in the treatment of refractory obsessive-compulsive disorder and major depressive disorder. However, in some patients lesions cannot be reliably generated due to patient-specific skull morphologies and properties. Despite screening patients for MRgFUS-AC using skull density ratio (SDR), up to 25% of cases experience treatment failure. This variability in technical success limits the real-world applicability of an otherwise highly impactful treatment, and a better predictor of success is needed.

Methods: This study analyzed data from 60 attempted MRgFUS-AC treatments in 57 patients between 2017 and 2024. Treatments were categorized as success or failure based on lesion volume. Preoperative parameters, including SDR, skull thickness, angle of incidence, CSF volume, brain and head volumes, and lesion side, were recorded. Logistic and machine learning models were evaluated to construct a preoperative model to predict the probability of technical success.

Results: A total of 157 lesions were treated, of which 31 experienced treatment failure. Higher SDR, thinner skulls, and lower incident angles were significantly associated with successful outcomes (all p < 0.05). The logistic regression model performed the best among the models tested, with an accuracy of 0.81 ± 0.07 and an F1 score of 0.89 ± 0.04. The model was incorporated into a predictive tool to aid in identifying candidates for MRgFUS-AC.

Conclusions: SDR, skull thickness, and angle of incidence significantly influenced the likelihood of successful MRgFUS-AC lesioning. Incorporating these three parameters into a predictive tool can dramatically reduce technical failure rates and may be especially informative in patients with an SDR between 0.35 and 0.55.

Objective: Resection of common peroneal nerve (CPN) schwannomas is generally believed to be associated with a high risk of postoperative deficit, especially the chance for development of a foot drop. The goal of this study was to investigate the surgical results for resection of schwannomas from the CPN around the knee and specifically the chance of developing a postoperative motor deficit.

Methods: Data from 36 patients with sporadic schwannomas and 8 patients with schwannomatosis (12 schwannomas total) treated at two centers were retrospectively analyzed. For sporadic cases, different locations around the knee were compared (i.e., proximal to the fibular head [FH], at the FH, and distal to the FH), taking into account the preoperative duration of symptoms, size at presentation, and surgical results of resection. The literature was systematically reviewed for reported cases by searching the PubMed and Embase databases.

Results: A total of 24 schwannomas proximal to the FH were surgically treated: 11 at the FH, and 13 distal to the FH. For the entire cohort, the mean size of CPN schwannomas distal to the FH at presentation was smaller (1.4 × 1.8 cm) compared with those proximal to (2.0 × 2.2 cm) and at (2.2 × 2.3 cm) the FH, although these differences were not statistically significant. The mean preoperative duration of symptoms was slightly longer for schwannomas distal to the FH (35 months) than for those proximal to the FH (21 months) and at the FH (27 months); however, this difference was not significant. Postoperative deficits occurred in 3 sporadic cases: 2 patients with temporary weakness (Medical Research Council grade 4) that completely resolved within several months and 1 patient who had previously undergone surgery elsewhere and presented with deficits and in whom weakness increased after resection. Improvement in preoperative deficits was observed in 1 patient with extensor hallucis longus muscle paralysis that completely recovered. One patient with schwannomatosis developed muscle weakness after resection of a plexiform schwannoma. A systematic review of 21 previously reported cases in the literature showed that larger CPN schwannomas (> 5 cm) were more likely to result in permanent motor deficits.

Conclusions: This retrospective study of 44 patients shows that peroneal nerve schwannomas around the knee can be safely removed with a low risk of deficits. The systematic review of the literature suggests that larger schwannomas are more likely to result in permanent deficit. In the authors' opinion, CPN schwannomas can best be resected, preferably when the lesion is relatively small.

Objective: The authors evaluated whether glucagon-like peptide-1 receptor agonists (GLP-1-RAs) improve outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH), spontaneous intracerebral hemorrhage (sICH), and acute ischemic stroke (AIS) and reduce the overall incidence of these events.

Methods: This retrospective study leveraged TriNetX data (2014-2024) to identify patients with aSAH, sICH, or AIS. Individuals receiving exenatide, lixisenatide, semaglutide, dulaglutide, liraglutide, or tirzepatide within 8 weeks of diagnosis were propensity matched to controls. Outcomes (e.g., mortality, rebleeding/recurrence, seizures, hydrocephalus) were assessed at 6 and 12 months; the incidence rates of stroke types were examined at 1 and 2 years.

Results: For aSAH patients, GLP-1-RA use at 6 months reduced rebleeding (OR 0.73, p = 0.003) and mortality (OR 0.41, p < 0.001) and at 1 year lowered cognitive deficits (OR 0.63, p = 0.034) and mortality (OR 0.39, p < 0.001). In sICH patients, GLP-1-RAs decreased hydrocephalus (OR 0.37, p = 0.005) and seizures (OR 0.56, p = 0.007) at 6 months, with persistent benefits at 1 year (hydrocephalus, OR 0.38, p = 0.007; seizures, OR 0.63, p = 0.018), alongside lower mortality (OR 0.45-0.40, both p < 0.001) and rebleeding (OR 0.70-0.69, both p < 0.001) rates. In AIS patients, mortality fell at 6 months (OR 0.27, p < 0.001) and 1 year (OR 0.44, p < 0.001), with reduced recurrence (OR 0.60, p < 0.001) and lower hydrocephalus (OR 0.32, p < 0.001) and seizure (OR 0.43, p < 0.001) rates at 6 months. At 1 year, GLP-1-RA users had lower incidence rates of SAH (OR 0.64, p = 0.001), ICH (OR 0.62, p < 0.001), and AIS (OR 0.82, p = 0.003), which were sustained at 2 years (ORs 0.77-0.87, all p < 0.05). Adverse events were similar.

Conclusions: GLP-1-RAs were associated with improved survival and fewer complications across stroke subtypes, plus reduced hemorrhagic and ischemic stroke incidence. Prospective trials are warranted to confirm these observations.

Objective: Since 2021, there has been a revolution in the understanding of the mutational landscape of sporadic cerebral cavernous malformations (CCMs), with the key discovery of somatic mutations in the PIK3CA and MAP3K3 genes. These genetic alterations have provided new insights into the pathophysiology of CCMs and opened potential venues for personalized treatments. However, establishing robust clinicoradiological and molecular correlations is essential to guide targeted therapeutic approaches and optimize patient outcomes.

Methods: This study included a cohort of 89 patients diagnosed with sporadic CCMs. The mutational status of each patient was determined using next-generation sequencing (NGS) targeting known mutations including the PIK3CA, MAP3K3, and CCM genes. NGS findings were confirmed by droplet digital polymerase chain reaction for PIK3CA and MAP3K3 mutations. Clinical and radiological data, including Zabramski classification data, were systematically recorded. Statistical analysis was performed to identify significant clinicoradiological and molecular correlations.

Results: In the cohort, PIK3CA somatic mutations were identified in 43 patients (48%), while MAP3K3 somatic mutations were found in 29 (33%). Clinically, PIK3CA-mutated lesions were less frequently revealed by intracranial hypertension (9.3% vs 19.6%; adjusted OR 0.09, p = 0.006), while for MAP3K3-mutated lesions, seizure as a mode of onset was significantly more frequent (85.7% vs 51.7%, p = 0.002). Radiologically, midline lesions were significantly more frequent in the PIK3CA-mutated group (19.0% vs 2.2%, p = 0.01). Importantly, in univariate analysis, the presence of a brainstem lesion was a significant independent predictor of PIK3CA somatic mutation (14.3% vs 2.2%; unadjusted OR 7.33, p = 0.03).

Conclusions: This study presents new findings linking genetic mutations with clinicoradiological features in sporadic CCMs. The significant association of PIK3CA somatic mutations with brainstem location highlights a potential avenue for personalized therapeutic strategies targeting this mutation, considering the significantly increased morbidity and surgical challenge associated with brainstem lesions. These findings reinforce the importance of integrating genetic data into clinical practice to improve patient outcomes and develop new therapies for CCMs.

Objective: Neurosurgery is a high-risk specialty with a low margin of error, and neurosurgeons have a higher medicolegal risk than practitioners in many other specialties. The aim of this study was to provide a current medicolegal landscape of cranial surgery in Canada.

Methods: In this retrospective descriptive study, the authors evaluated 10 years (2012-2021) of cranial neurosurgical data on closed legal actions, medical regulatory authority (College) cases, and hospital complaints against neurosurgeons that had been submitted to the Canadian Medical Protective Association (CMPA). Only cranial cases, even those involving ventriculoperitoneal shunt (VPS) placement or catheter or wire insertion in the brain, were eligible for study inclusion. Excluded cases were those involving pediatric patients and angiography, radiation, ultrasound, or percutaneous procedures.

Results: Seventy-six cranial cases were included in the study. Neurosurgeons had a significantly higher medicolegal risk compared to that of the overall CMPA surgeon membership. Civil legal actions accounted for more than half of all the cranial cases. Fifty-four percent of cases involved postoperative complications, and 21% involved VPS placement. Communication issues were commonly named factors leading to a medicolegal complaint throughout the data.

Conclusions: This is the first report on the Canadian experience of medicolegal cranial surgery cases. These cases most commonly involved tumor excision, VPS insertion, and decompressive craniectomy. The VPS cases were unexpectedly common and should be further investigated. A breakdown in communication was a major theme in the medicolegal data repository.

Objective: Assessing the consistency and precision of microanastomosis performance is crucial in neurosurgical training. Traditional methods rely on expert observation, which can be subjective and time-consuming. The aim of this study was to develop and validate a deep learning model using long short-term memory (LSTM) architecture for objective evaluation of microanastomosis performance by predicting and comparing suturing executions.

Methods: An LSTM-based neural network was developed to model and predict hand movements during microvascular anastomosis simulation. Video data were collected from 2 expert neurosurgeons performing microanastomosis twice, 1 year apart (sessions 1 and 2). Surgeon 1 performed interrupted suturing, and surgeon 2 performed continuous suturing. Additionally, a trainee with minimal microsurgical experience performed the interrupted suturing procedure once. Model performance was quantitatively assessed by comparing predicted and actual suturing executions using Kullback-Leibler (KL) divergence. Economy and flow of motion were also analyzed.

Results: The LSTM-based model accurately predicted suturing movements. Surgeon 1 demonstrated KL divergence values of 0.00063 (session 1) and 0.00061 (session 2), and surgeon 2 had values of 0.00082 (session 1) and 0.00016 (session 2). The trainee exhibited higher KL divergence (0.00196), reflecting less consistent performance. The economy of motion was assessed, showing mean Euclidean distances of 7.41 mm (session 1) and 5.85 mm (session 2) for surgeon 1, 10.53 mm (session 1) and 14.46 mm (session 2) for surgeon 2, and 10.50 mm for the trainee. The flow of motion analysis indicated median time intervals between sutures of 31.96 seconds (session 1) and 29.57 seconds (session 2) for surgeon 1, 21.53 seconds (session 1) and 21.50 seconds (session 2) for surgeon 2, and 101.23 seconds for the trainee.

Conclusions: The LSTM-based model objectively assessed microanastomosis performance, capturing consistency and efficiency. Economy and flow of motion metrics were further validated. Future studies will extend the model's application to more surgeons and refine interpretation of the performance metrics.

Tufts Medical Center grew from the Boston Dispensary, which was initially founded in 1796 by public-spirited Bostonians including Samuel Adams and Paul Revere. The union with Floating Hospital for Children, Pratt Diagnostic Center, and Tufts College Medical School transformed the Dispensary into the New England Medical Center in 1929. Though neurosurgical procedures were performed as early as the 1920s, the division was not established until 1948, and the residency program received Accreditation Council for Graduate Medical Education accreditation in 1950. Tufts-New England Medical Center was formed in 1968 after a merger with the newly renamed Tufts University School of Medicine and was again renamed Tufts Medical Center in 2008. The department has been led by Drs. Bertram Selverstone, Bennet Stein, William Shucart, Carl Heilman, and Ron Riesenburger. The residency program has produced neurosurgeons who have gone on to shape the field.