Incidental durotomy during tubular microdiscectomy does not preclude same-day discharge.

PURPOSE: One of the major advantages of a minimally invasive microdiscectomy is that when CSF leak occurs, there is minimal anatomic dead space for ongoing leakage following removal of the tubular retractor. However, there are no published reports that address the safety and long-term outcomes of same-day discharge for CSF leak after tubular microdiscectomy. METHODS: This is a retrospective compartive study of 30 patients with incidental durotomy during minimally invasive tubular microdiscectomy occurring between January 1, 2009 to August 31, 2023 at our institution. RESULTS: There were 16 patients (53%) admitted to hospital and 14 (47%) patients discharged home the same day following CSF leak. There were no differences in patient demographics between the two groups at baseline. Twenty-nine out of 30 (97%) of the patients had onlay duraplasty, and one (3%) patient was repaired using sutures through the tubular retractor. None were converted to an open approach. The hospitalized group was kept on bed rest overnight or for 24 h. The discharge group was kept on best rest for 2 h or mobilized immediately after surgery. No patients in either group required readmission or revision surgery for CSF leak. The average length of admission for the hospitalized group was 2.4 ± 4.0 days. CONCLUSION: Patients with CSF leak during minimally invasive tubular microdiscectomy can be safely discharged home the same day.

KEAP1-mutant atypical meningioma: illustrative case.

BACKGROUND: While genetic testing of tumors is commonly used to inform the selection of systemic therapies, there is limited evidence for the application of radiotherapy for brain cancer. Recent studies have shown that Kelch-like ECH-associated protein 1 (KEAP1), a key regulator of cellular responses to oxidative and electrophilic stress, is associated with radioresistance in multiple cancer types. Several studies have reported the clinical significance of KEAP1 mutation in brain metastasis; however, the effect of KEAP1 mutations on radioresponse in meningioma has never been reported. OBSERVATIONS: The authors present the case of a 40-year-old female with a KEAP1 mutation-positive atypical meningioma that was initially treated with resection followed by intensity-modulated radiation therapy (IMRT). Recurrence was observed at 15 months, requiring reoperation and adjuvant stereotactic radiosurgery (SRS). An excellent treatment response was observed at 7 months post-SRS with an improvement in reported symptoms, although bevacizumab was required for the resolution of radiation necrosis observed 2 months post-SRS. LESSONS: To the authors' knowledge, this is the first report of KEAP1-mutant meningioma, including its clinical course after comprehensive management. Notably, treatment included multimodal radiotherapy with IMRT followed by SRS. SRS led to an excellent treatment response at the 7-month follow-up. However, radiation necrosis developed after both radiotherapy treatments, suggesting that radiological modification can be beneficial in patients with KEAP1 mutations. https://thejns.org/doi/10.3171/CASE24387.

Stereotactic body radiotherapy for painful spinal metastases: a decade of experience at a single institution.

OBJECTIVE: This study aimed to retrospectively evaluate the efficacy of stereotactic body radiotherapy (SBRT) for pain relief in patients with painful spinal bone metastases (SBMs) and to identify key factors contributing to treatment outcomes. METHODS: The authors conducted a retrospective analysis of adult patients who underwent SBRT for painful solid tumor SBMs between March 2012 and January 2023. During this period, SBRT was performed adhering to the International Spine Radiosurgery Consortium guidelines and international consensus recommendations for target volume delineation. To be included, patients needed to experience persistent pain directly associated with SBMs, warranting regular opioid treatment. Positive pain relief post-SBRT was defined by three criteria: 1) a decrease in the severity of pain; 2) reduction in opioid dosage; and 3) concurrent improvement in daily activities. The revised Tokuhashi score and Spine Instability Neoplastic Score were used to identify crucial factors influencing treatment outcomes. RESULTS: This study included 377 patients, covering 576 lesions across 759 vertebrae. Of these, 332 lesions showed significant pain relief within 3 months following SBRT. Lower pain relief rates were observed in patients with a revised Tokuhashi score of 0-8 or in patients with diabetes mellitus. In contrast, higher relief rates were linked to treating a single painful SBM in 1 SBRT course, and greater contouring of the involved sectors according to International Spine Radiosurgery Consortium guidelines and international consensus recommendations. The highest pain relief rate was observed in patients with prostate cancer (73.8%), whereas the lowest rate was observed in patients with hepatocellular carcinoma (36.4%). The presence of pre-SBRT vertebral fractures, the dosage and fraction of SBRT, and the use of concurrent systemic cancer therapies or antiresorptive agents, including bisphosphonates and denosumab, did not notably influence the pain relief efficacy of SBRT. Comprehensive medical records 6 months after SBRT treatment were available for only 362 lesions. The overall rate of pain relief observed was 32.6%. CONCLUSIONS: SBRT is an effective treatment approach for managing painful SBMs, achieving a pain relief rate of 57.6% within 3 months and maintaining a rate of 32.6% at 6 months after treatment. The transition to osteoblastic lesions may potentially improve the stability of SBMs, indicated by lower Spine Instability Neoplastic Score, which in turn could extend pain relief management.

Stereotactic Radiosurgery for Residual, Recurrent, and Metastatic Hemangiopericytomas: A Single-Institution Retrospective Experience.

BACKGROUND AND OBJECTIVES: Hemangiopericytomas are infrequent vascular tumors originating from Zimmermann pericytes. The conventional treatment involves gross total resection, followed by adjuvant radiotherapy. Nevertheless, their tendency to infiltrate dural sinuses, high vascularity, and anatomic complexity pose challenges for radical resection, leading to a significant risk of recurrence. Stereotactic radiosurgery (SRS) has emerged as a promising adjuvant therapy to address these challenges. Our study provides the largest single-institutional retrospective, aiming to evaluate the effectiveness and safety of SRS as a treatment modality for residual, recurrent, and metastatic hemangiopericytomas. METHODS: From 1998 to 2023, 27 patients with 101 tumors underwent CyberKnife SRS at Stanford University Medical Center. The median age was 51 years at the time of treatment. The median follow-up period from SRS was 103 months (range: 6-250). All patients underwent upfront surgical resection. The median tumor volume was 1.5 cc. The median single-fraction equivalent dose was 19 Gy. The SRS was administered at the 76% of the median isodose line (range: 64-89). RESULTS: Of the 101 treated tumors, 24 (23.8%) progressed with a median time to recurrence of 30 months. At 10 years, the rates of local tumor control (LTC), overall survival (OS), and progression-free survival (PFS) were 74.3%, 80.8%, and 67%, respectively. In patients with metastatic lesions, the LTC rates were significantly greater when compared with those with residual or recurrent tumors. There was no significant difference between patients with residual, recurrent, and metastatic hemangiopericytomas in OS and PFS. Notably, no cases of radiation-induced adverse events were detected. CONCLUSION: SRS leads to excellent LTC, PFS, and OS at 10 years with negligible risk for adverse events. Therefore, it is an effective and safe management modality for patients with residual, recurrent, and metastatic hemangiopericytomas.

Recurrent choroid plexus carcinoma treated with CyberKnife radiosurgery: illustrative case.

BACKGROUND: Choroid plexus carcinomas (CPCs) are rare malignant brain tumors primarily affecting children younger than 2 years old. These tumors originate from the choroid plexus epithelium and are a subtype of choroid plexus tumors, which account for 1%-4% of pediatric brain tumors. Although CPCs often show a notably high recurrence rate after surgery, the standard treatment approach remains gross-total resection (GTR) of the tumor, given the lack of clinical data supporting the effectiveness of adjunct treatment options such as radiotherapy or chemotherapy. OBSERVATIONS: A 16-year-old female with a history of a recurrent cranial CPC resistant to surgery and radiotherapy was treated with CyberKnife stereotactic radiosurgery (SRS), following resection. The procedures successfully maintained local disease control for 41 months; however, there was a subsequent recurrence, ultimately leading to the death of the patient. LESSONS: CPC treatment remains challenging. SRS can be used as a viable adjunct to surgery, which remains the gold standard, although it can also be considered for nonsurgical candidates or when GTR cannot be achieved. Nevertheless, it is crucial to conduct additional research to explore diverse approaches for radiosurgery, including its role as the primary treatment modality versus its combination with surgery, radiotherapy, or chemotherapy. https://thejns.org/doi/10.3171/CASE23748.

Primary Stereotactic Body Radiotherapy for Spinal Bone Metastases From Lung Adenocarcinoma.

OBJECTIVE: This study aimed to assess the results of primary stereotactic body radiotherapy (SBRT) for spinal bone metastases (SBM) originating from lung adenocarcinoma (ADC). We considered the revised Tokuhashi score (rTS), Spinal Instability Neoplastic Score (SINS), and genetic characteristics. METHODS: We examined adult patients with lung ADC who underwent primary SBRT (using the CyberKnife System) for SBM between March 2012 and January 2023. RESULTS: We analyzed data from 99 patients, covering 152 SBM across 194 vertebrae. The overall local control (LC) rate was 77.6% for SBM from lung ADC, with a LC rate of 90.7% at 1 year. The median period for local progression (LP) occurrence was recorded at 10.0 (3-52) months. Additionally, Asian patients demonstrated higher LC rates than White patients. Utilizing the rTS and SINS as predictive tools, we revealed that a poor survival prognosis and an unstable spinal structure were associated with increased rates of LP. Furthermore, the presence of osteolytic bone destructions and pain complaints were significantly correlated with the occurrence of LP. In the cohort of this study, 108 SBM underwent analysis to determine the expression levels of programmed cell death ligand 1 (PD-L1). Additionally, within this group, 60 showed mutations in the epidermal growth factor receptor (EGFR) alongside PD-L1 expression. Nevertheless, these genetic differences did not result in statistically significant differences in the LC rate. CONCLUSION: The one-year LC rate for primary SBRT targeting SBM from lung ADC stood at 90.7%, particularly with the use of the CyberKnife System. Patients achieving LC exhibited significantly longer survival times compared to those with LP.

Stereotactic radiosurgery for facial nerve hemangioma: Case report and systematic review.

BACKGROUND: Facial nerve hemangiomas (FNHs) are rare tumors that primarily occur near the geniculate ganglion in the temporal bone. Despite their rarity, they can cause significant facial nerve dysfunction. The optimal management approach for FNHs remains uncertain, with surgery being the mainstay but subject to debate regarding the extent of resection and preservation of the facial nerve. METHODS: Systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We queried the PubMed/Medline (accessed on 5 March 2024) electronic database using combinations of the following search terms and words text: "geniculate ganglion hemangioma", "ganglional hemangioma", "hemangioma of the facial nerve", "facial hemangioma", and "intratemporal hemangioma". RESULTS: We identified a total of 30 literatures (321 patients). The most common site involved for the facial nerve hemangioma was the geniculate ganglion area followed by internal auditory canal, tympanic segment, labyrinthine segment and mastoid involvement. All patients were treated with conservative management or surgery. We report a 48-year-old female patient with HB grade 2 facial palsy and hemifacial spasm underwent SRS using Cyberknife technology. The treatment targeted the FNH in the left internal acoustic canal near the geniculate ganglion. Six months post-treatment, clinical improvement was evident, and lesion control was confirmed in a follow-up brain MRI. CONCLUSION: The rarity of FNHs contributes to the lack of consensus on optimal management. This illustrative case demonstrates the feasibility of SRS as a standalone treatment for FNHs.

Naturalistic acute pain states decoded from neural and facial dynamics.

Pain is a complex experience that remains largely unexplored in naturalistic contexts, hindering our understanding of its neurobehavioral representation in ecologically valid settings. To address this, we employed a multimodal, data-driven approach integrating intracranial electroencephalography, pain self-reports, and facial expression quantification to characterize the neural and behavioral correlates of naturalistic acute pain in twelve epilepsy patients undergoing continuous monitoring with neural and audiovisual recordings. High self-reported pain states were associated with elevated blood pressure, increased pain medication use, and distinct facial muscle activations. Using machine learning, we successfully decoded individual participants' high versus low self-reported pain states from distributed neural activity patterns (mean AUC = 0.70), involving mesolimbic regions, striatum, and temporoparietal cortex. High self-reported pain states exhibited increased low-frequency activity in temporoparietal areas and decreased high-frequency activity in mesolimbic regions (hippocampus, cingulate, and orbitofrontal cortex) compared to low pain states. This neural pain representation remained stable for hours and was modulated by pain onset and relief. Objective facial expression changes also classified self-reported pain states, with results concordant with electrophysiological predictions. Importantly, we identified transient periods of momentary pain as a distinct naturalistic acute pain measure, which could be reliably differentiated from affect-neutral periods using intracranial and facial features, albeit with neural and facial patterns distinct from self-reported pain. These findings reveal reliable neurobehavioral markers of naturalistic acute pain across contexts and timescales, underscoring the potential for developing personalized pain interventions in real-world settings.

Neurosurgical Operative Cancellations in Canada: A Multicentre Retrospective Cohort Study.

INTRODUCTION: Operative cancellations adversely affect patient health and impose resource strain on the healthcare system. Here, our objective was to describe neurosurgical cancellations at five Canadian academic institutions. METHODS: The Canadian Neurosurgery Research Collaborative performed a retrospective cohort study capturing neurosurgical procedure cancellation data at five Canadian academic centres, during the period between January 1, 2014 and December 31, 2018. Demographics, procedure type, reason for cancellation, admission status and case acuity were collected. Cancellation rates were compared on the basis of demographic data, procedural data and between centres. RESULTS: Overall, 7,734 cancellations were captured across five sites. Mean age of the aggregate cohort was 57.1 ± 17.2 years. The overall procedure cancellation rate was 18.2%. The five-year neurosurgical operative cancellation rate differed between Centre 1 and 2 (Centre 1: 25.9%; Centre 2: 13.0%, p = 0.008). Female patients less frequently experienced procedural cancellation. Elective, outpatient and spine procedures were more often cancelled. Reasons for cancellation included surgeon-related factors (28.2%), cancellation for a higher acuity case (23.9%), patient condition (17.2%), other factors (17.0%), resource availability (7.0%), operating room running late (6.4%) and anaesthesia-related (0.3%). When clustered, the reason for cancellation was patient-related in 17.2%, staffing-related in 28.5% and operational or resource-related in 54.3% of cases. CONCLUSIONS: Neurosurgical operative cancellations were common and most often related to operational or resource-related factors. Elective, outpatient and spine procedures were more often cancelled. These findings highlight areas for optimizing efficiency and targeted quality improvement initiatives.

Dosimetric Comparison of Dedicated Radiosurgery Platforms for the Treatment of Essential Tremor: Technical Report.

Essential tremor (ET) is one of the most common adult movement disorders. As the worldwide population ages, the incidence and prevalence of ET is increasing. Although most cases can be managed conservatively, there is a subset of ET that is refractory to medical management. By virtue of being "reversible", deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of the thalamus is one commonly accepted intervention. As an alternative to invasive and expensive DBS, there has been a renaissance in treating ET with lesion-based approaches, spearheaded most recently by high-intensity focused ultrasound (HIFU), the hallmark of which is that it is non-invasive. Meanwhile, stereotactic radiosurgical (SRS) lesioning of VIM represents another time-honored lesion-based non-invasive treatment of ET, which is especially well suited for those patients that cannot tolerate open neurosurgery and is now also getting a "second look". While multiple SRS platforms have been and continue to be used to treat ET, there is little in the way of dosimetric comparison between different technologies. In this brief technical report we compare the dosimetric profiles of three major radiosurgical platforms (Gamma Knife, CyberKnife Robotic Radiosurgery, and Zap-X Gyroscopic Radiosurgery (GRS)) for the treatment of ET. In general, the GRS and Gamma Knife were shown to have the best theoretical dosimetric profiles for VIM lesioning. Nevertheless the relevance of such superiority to clinical outcomes requires future patient studies.

Stereotactic Radiosurgery for Ependymoma in Pediatric and Adult Patients: A Single-Institution Experience.

BACKGROUND AND OBJECTIVES: Ependymoma is commonly classified as World Health Organization grade 2 with the anaplastic variant categorized as grade 3. Incomplete resection or anaplastic features can result in unfavorable outcomes. Stereotactic radiosurgery (SRS) provides a minimally invasive approach for recurrent ependymomas. Our study investigates the efficacy and safety of SRS for grade 2 and 3 ependymomas in pediatric and adult populations. METHODS: We conducted a retrospective analysis on 34 patients with 75 ependymomas after CyberKnife SRS between 1998 and 2023. Fourteen were pediatric (3-18 years), and 20 were adult (19-75 years) patients. The median age was 21 years, and the median tumor volume was 0.64 cc. The median single-fraction equivalent dose was 16.6 Gy, with SRS administered at 77% of the median isodose line. RESULTS: After a median follow-up of 42.7 months (range: 3.8-438.3), 22.7% of ependymomas progressed. The 5-year local tumor control rate was 78.1%, varying between 59.6% and 90.2% for children and adults, with grade 2 at 85.9% compared with 58.5% for grade 3 tumors. The 5-year overall survival rate was 73.6%, notably higher in adults (94.7%) than in children (41%), and 100% for grade 2 but decreased to 35.9% for grade 3 patients. The 5-year progression-free survival rate was 68.5%, with 78.3% and 49.2% for adults and children, respectively, and a favorable 88.8% for grade 2, contrasting with 32.6% for grade 3 patients. Symptom improvement was observed in 85.3% of patients. Adverse radiation effects occurred in 21.4% of pediatric patients. CONCLUSION: Our study supports SRS as a viable modality for pediatric and adult patients with grade 2 and 3 ependymomas. Despite lower local tumor control in pediatric and grade 3 cases, integrating SRS holds promise for improved outcomes. Emphasizing careful patient selection, personalized treatment planning, and long-term follow-up is crucial for optimal neurosurgical outcomes.

Automatic Segmentation of Vestibular Schwannomas: A Systematic Review.

BACKGROUND: Vestibular schwannomas (VSs) are benign tumors often monitored over time, with measurement techniques for assessing growth rates subject to significant interobserver variability. Automatic segmentation of these tumors could provide a more reliable and efficient for tracking their progression, especially given the irregular shape and growth patterns of VS. METHODS: Various studies and segmentation techniques employing different Convolutional Neural Network architectures and models, such as U-Net and convolutional-attention transformer segmentation, were analyzed. Models were evaluated based on their performance across diverse datasets, and challenges, including domain shift and data sharing, were scrutinized. RESULTS: Automatic segmentation methods offer a promising alternative to conventional measurement techniques, offering potential benefits in precision and efficiency. However, these methods are not without challenges, notably the "domain shift" that occurs when models trained on specific datasets underperform when applied to different datasets. Techniques such as domain adaptation, domain generalization, and data diversity were discussed as potential solutions. CONCLUSIONS: Accurate measurement of VS growth is a complex process, with volumetric analysis currently appearing more reliable than linear measurements. Automatic segmentation, despite its challenges, offers a promising avenue for future investigation. Robust well-generalized models could potentially improve the efficiency of tracking tumor growth, thereby augmenting clinical decision-making. Further work needs to be done to develop more robust models, address the domain shift, and enable secure data sharing for wider applicability.

Chronic Subdural Hematoma Drainage under Local versus General Anesthesia: Systematic Review and Meta-Analysis.

BACKGROUND: Chronic subdural hematoma (CSDH) is one of the most frequently encountered neurosurgical conditions. Although the mainstay treatment of chronic subdural hematoma has been burr-hole drainage, no consensus yet exists on the optimal anesthetic strategy between general anesthesia (GA) and local anesthesia (LA). This systematic review compares postoperative outcomes after CSDH evacuation under LA and GA. METHODS: A search was conducted in MEDLINE (1946 to November 2023), Embase (1974 to November 2023), and PubMed (up to November 2023). We followed the PRISMA guidelines to systematically screen studies. RESULTS: Our literature search identified 629 studies, out of which 12 were included. There were 1035 patients in the LA group and 699 patients in the GA group. Our meta-analysis found that the LA group had significantly shorter operative time (mean difference, -29.28 minutes; P < 0.0001), length of admission (mean difference, -1.58 days; 95% confidence interval [CI], -2.40 to -0.76 days; P = 0.0002), and postoperative complications rate (odds ratio [OR], 0.38; 95% CI, 0.25-0.59; P < 0.0001) compared with GA. There was no significant difference between the 2 groups in revision rate (OR, 0.77; 95% CI, 0.39-1.51; P = 0.45) and mortality (OR, 1.23; 95% CI, 0.63-2.43; P = 0.55). CONCLUSIONS: In this meta-analysis, LA shows benefits in shorter operative time, shorter admission length, and fewer postoperative complications. This finding makes LA a less invasive alternative to GA, especially in elderly patients.

Long-Term (>24 Months) Duration of Symptoms Negatively Impacts Patient-Reported Outcomes Following Anterior Cervical Discectomy and Fusion for Cervical Radiculopathy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate the impact of long symptom duration (>24 mo) on patient self-reported outcomes for pain, function, and quality of life following anterior cervical discectomy and fusion (ACDF) for cervical radiculopathy. SUMMARY OF BACKGROUND DATA: ACDF is an effective treatment to relieve the symptoms of cervical radiculopathy. However, there is no consensus on whether prolonged preoperative length of symptoms negatively impacts postoperative outcomes. METHODS: This study included consecutive patients who underwent ACDF for cervical radiculopathy from May 1, 2012 to Dec 1, 2019 by a single surgeon. Patients were stratified by short (<24 mo) and long (>24 mo) duration of symptoms. Outcomes including visual analog scale (VAS) neck and arm, neck disability index (NDI), EuroQol-5D (EQ-5D), and overall state of health (EQ-VAS) were compared between cohort both for absolute values and percentage of patients achieving minimal clinically important difference. RESULTS: A total of 111 consecutive patients were included in our study, including 59 patients in the short symptom duration group and 52 patients in the long symptom duration group. The mean age of the patients was 51.4±9.4 and 41 (36.9%) were female. The baseline VAS neck and arm, NDI, EQ-5D, and EQ-VAS were similar between groups. Patients in both long and short symptom duration groups had clinical improvement following surgery. However, patients with short symptom duration had better VAS Neck and EQ-5D outcomes, and were more likely to meet minimal clinically important difference for NDI, EQ-5D, or any outcome. Multivariate analysis confirmed symptom duration <24 months as an independent predictor for better patient-reported outcomes. CONCLUSION: We appreciated better clinical outcomes in patients with shorter symptom duration who received ACDF for cervical radiculopathy. On the basis of this data, we advocate for prompt treatment of cervical radiculopathy to avoid the potential for long-term impairment. LEVEL OF EVIDENCE: Level 3.

Bilateral occipital condyle fracture with an avulsion fracture of the foramen magnum: nonoperative care guided by a traction test. Illustrative case.

BACKGROUND: Bilateral occipital condyle fractures (OCFs) with involvement of the inferior clivus, otherwise known as "avulsion of the anterior foramen magnum," are an exceedingly rare injury with only a few published reports. OBSERVATIONS: A 24-year-old male presented with bilateral OCFs with involvement of the clivus after a motor vehicle accident. The patient had no neurological deficits and was successfully managed nonoperatively using a halo vest. The authors used a traction test to guide the duration of nonoperative care. The operative and nonoperative management of this rare injury is discussed with respect to other cases in the literature. LESSONS: External immobilization through a halo vest is an effective treatment option for bilateral OCFs with clivus involvement. The traction test can be used, along with computed tomography, to guide the duration of treatment.

Spinal metastases of pineal region glioblastoma with primitive neuroectodermal features highlighting the importance of molecular diagnoses: illustrative case.

BACKGROUND: Glioblastoma (GBM) is the most common primary brain tumor with poor patient prognosis. Spinal leptomeningeal metastasis has been rarely reported, with long intervals between the initial discovery of the primary tumor in the brain and eventual spine metastasis. OBSERVATIONS: Here, the authors present the case of a 51-year-old male presenting with 7 days of severe headache, nausea, and vomiting. Magnetic resonance imaging of the brain and spine demonstrated a contrast-enhancing mass in the pineal region, along with spinal metastases to T8, T12, and L5. Initial frozen-section diagnosis led to the treatment strategy for medulloblastoma, but further molecular analysis revealed characteristics of isocitrate dehydrogenase-wild type, grade 4 GBM. LESSONS: Glioblastoma has the potential to show metastatic spread at the time of diagnosis. Spinal imaging should be considered in patients with clinical suspicion of leptomeningeal spread. Furthermore, molecular analysis should be confirmed following pathological diagnosis to fine-tune treatment strategies.