Nasser Mohammed

Objective: To evaluate the factors contributing to poor outcomes in patients with acute traumatic subdural hematoma (aSDH) who developed nonconvulsive status epilepticus (NCSE). Background: NCSE in patients with aSDH is an underdiagnosed yet fatal complication that requires prompt diagnosis and treatment. A high degree of clinical suspicion and evaluation with continuous EEG is required for prompt diagnosis and treatment. Design/Methods: This is a single-institution retrospective study approved by the local IRB. Patients with traumatic brain injury (TBI) with aSDH diagnosed with status epilepticus between the years 2016–2020 were included. Demographic, clinical, imaging, treatment, and EEG details were reviewed and collected in a HIPPA-compliant format. Logistic regression analysis was used to evaluate factors contributing to poor outcomes. Results: Out of a total of 540 patients, who had presented with traumatic acute intra-cerebral hemorrhage between the years 2016–2022, 28 patients with traumatic aSDH who had presented with status epileptics during the same hospitalization were included in the present study. NCSE was the most common form of status epilepticus (27/28). The mean age was 67 (range 20–92) years and 17(60%) were male. 12(48%) of the patients had an initial presenting GCS of 7 or less. The mean length of stay in the hospital was 16 (5–44) days. Overall mortality was 19(64%). Logistic regression analysis identified the presence of central spikes on EEG (p:0.43, OR:12.72; 95% CI 1.083–149.35) and thickness of aSDH> 1cm (p: 0.025; OR: 16.545; 95%CI: 1.426–191.95) as predictors of mortality in both univariate and multivariate analysis. Good functional outcomes with mRS<2 were seen in rarely 10(35%) of these patients. Conclusions: Nonconvulsive status epilepticus (NCSE) is a common form of presentation of status epilepticus in patients with acute traumatic SDH. The presence of epileptiform activity in the central leads in EEG often leads to resistant seizures. NCSE carries a poor prognosis with high mortality. Disclosure: Dr. Mohammed has nothing to disclose. Miss Stebbins has nothing to disclose. The institution of Dr. Shah has received research support from Eisai pharma .

Objective: The present study aims to elucidate the factors contributing to poor outcomes in patients with acute seizures following Shaken Baby Syndrome (SBS). Background: SBS is the most common cause of severe neurological injury resulting from child abuse and is associated with subdural and retinal hemorrhages. Seizures are a common yet underdiagnosed feature of this syndrome and are associated with poor outcomes. Design/Methods: We retrospectively identified patients with SBS and seizures who were diagnosed between 2015–2020. Detailed chart review was performed under IRB-approved study criteria. Demographic, clinical, imaging, lab, and neurophysiology studies information was systematically collected. Logistic regression analysis was used to evaluate factors contributing to poor outcomes. Results: A total of 23 patients with acute seizures following SBS were included. The mean age was 7 months (range 3 weeks - 4 years). Six(26%) patients had a presenting GCS of 7 or less, while status epilepticus presented in 7(30%) patients. All included patients had acute traumatic subdural hematoma, retinal hemorrhage, and seizures in the acute period. Overall mortality was 2(9%). Logistic regression analysis identified craniotomy (p:0.01, OR:215.00; 95% CI 3.45–13408.47), SDH thickness >1 cm (p:0.02, OR:68.33; 95% CI 2.15–2173.12), midline shift >1 mm (p:0.03, OR:39.00; 95% CI 1.42–1067.60), and age >24 months (p:0.01, OR:215.00; 95% CI 3.45–13408.47) as predictors of mortality in both univariate and multivariate analysis. Of note, 19(83%) patients had an elevated serum glucose on presentation. Conclusions: Seizures in Shaken Baby Syndrome are associated with acute traumatic subdural hematoma, and about 1 in 3 children will develop status epilepticus. Patients with craniotomy to evacuate SDH, SDH thickness >1 cm, midline shift >1 mm, and older age at the time of injury have a worse prognosis. Disclosure: Miss Stebbins has nothing to disclose. Dr. Mohammed has nothing to disclose. The institution of Dr. Shah has received research support from Eisai pharma .

OBJECTIVE: The management of neurofibromatosis type 2 (NF2)–associated meningiomas is challenging. The role of Gamma Knife radiosurgery (GKRS) in the treatment of these tumors remains to be fully defined. In this study, the authors aimed to examine the role of GKRS in the treatment of NF2-associated meningiomas and to evaluate the outcomes and complications after treatment. METHODS: Seven international medical centers contributed data for this retrospective cohort. Tumor progression was defined as a ≥ 20% increase from the baseline value. The clinical features, treatment details, outcomes, and complications were studied. The median follow-up was 8.5 years (range 0.6–25.5 years) from the time of initial GKRS. Shared frailty Cox regression was used for analysis. RESULTS: A total of 204 meningiomas in 39 patients treated with GKRS were analyzed. Cox regression analysis showed that increasing the maximum dose (p = 0.02; HR 12.2, 95% CI 1.287–116.7) and a lower number of meningiomas at presentation (p = 0.03; HR 0.9, 95% CI 0.821–0.990) were predictive of better tumor control in both univariable and multivariable settings. Age at onset, sex, margin dose, location, and presence of neurological deficit were not predictive of tumor progression. The cumulative 10-year progression-free survival was 94.8%. Radiation-induced adverse effects were noted in 4 patients (10%); these were transient and managed medically. No post-GKRS malignant transformation was noted in 287 person-years of follow-up. CONCLUSIONS: GKRS achieved effective tumor control with a low and generally acceptable rate of complications in NF2-associated meningiomas. There did not appear to be an appreciable risk of post–GKRS-induced malignancy in patients with NF2-treated meningiomas.

Gautam U Mehta, MD, Gregory P Lekovic, MD, PhD, William H Slattery, MD, Derald E Brackmann, MD, Hao Long, MD, PhD, Hideyuki Kano, MD, PhD, Douglas Kondziolka, M

OBJECTIVE: Cranial nerve (CN) schwannomas are intracranial tumors that are commonly managed by stereotactic radiosurgery (SRS). There is a large body of literature supporting the use of SRS for vestibular schwannomas. Schwannomas of the oculomotor nerves (CNs III, IV, and VI) are rare skull base tumors, occurring close to the brainstem and often involving the cavernous sinus. Resection can cause significant morbidity, including loss of nerve function. As for other schwannomas, SRS can be used to manage these tumors, but only a handful of cases have been published so far, often among reports of other uncommon schwannoma locations. METHODS: The goal of this study was to collect retrospective multicenter data on tumor control, clinical evolution, and morbidity after SRS. This study was performed through the International Radiosurgery Research Foundation. Patients managed with single-session SRS for an oculomotor cranial nerve schwannoma (CN III, IV, or VI) were included. The diagnosis was based on diplopia or ptosis as the main presenting symptom and anatomical location on the trajectory of the presumed cranial nerve of origin, or prior resection confirming diagnosis. Demographic, SRS dose planning, clinical, and imaging data were collected from chart review of the treated patients. Chi-square and Kaplan-Meier analyses were performed. RESULTS: Seven institutions submitted data for a total of 25 patients. The median follow-up time was 41 months. The median age at the time of treatment was 52 years. There were 11 CN III schwannomas, 11 CN IV schwannomas, and 3 CN VI schwannomas. The median target volume was 0.74 cm ³ , and the median marginal dose delivered was 12.5 Gy. After SRS, only 2 patients (including the only patient with neurofibromatosis type 2) had continued tumor growth. Crude local control was 92% (23/25), and the 10-year actuarial control was 86%. Diplopia improved in the majority of patients (11/21), and only 3 had worsening following SRS, 2 of whom also had worsened ptosis, both in the context of tumor progression. CONCLUSIONS: SRS for schwannomas of the oculomotor, trochlear, and abducens nerves is effective and provides tumor control rates similar to those for other cranial nerve schwannomas. SRS allows improvement of diplopia in the majority of patients. SRS should therefore be considered as a first-line treatment option for oculomotor nerve schwannomas.

Objective To compare the histopathology of patent and nonpatent microvascular anastomosis using rat femoral artery end-to-end anastomosis model. Materials and Methods In 15 Sprague–Dawley rats, end-to-end anastomosis was performed on the right femoral artery. The classical method was used in four cases and one-way up method in 11 cases. The animals were sacrificed after 2 weeks and the anastomosis was subjected to histopathology. The pathological changes in patent and nonpatent cases were compared. Results The immediate patency rate and delayed patency (after 2 weeks) rate was 86.7% and 66.7%, respectively. The mean follow-up was 3 months. At sacrifice, 5/15 anastomosis were not patent. Marked subintimal thickening was noted in ⅘ (80%) of the nonpatent group, which was absent in the patent group. Severe loss or fibrosis of tunica media and marked adventitial inflammation were noted in all nonpatent cases (5/5, 100%). As much as ⅘ of the nonpatent cases had poor or indeterminate apposition; in contrast, good apposition was seen in 6/10 (60%) of the patent group. The mean clamp time and mean suturing time were significantly longer in the nonpatent group (69.2 minutes and 53.8 minutes, respectively) as compared with the patent group (48.8 minutes and 31.8 minutes, respectively). A single case that was initially nonpatent was found to have recanalized at 6 months. Conclusion Minimal intimal injury and reaction, minimal thinning of tunica media, mild-to-moderate adventitial changes, good apposition, and equidistant sutures were associated with a successful microvascular anastomosis. Short duration of vessel clamping time and suturing comes with experience and dedicated practice in a skills laboratory.

OBJECTIVE: Central neurocytomas (CNs) are uncommon intraventricular tumors, and their rarity renders the risk-to-benefit profile of stereotactic radiosurgery (SRS) unknown. The aim of this multicenter, retrospective cohort study was to evaluate the outcomes of SRS for CNs and identify predictive factors. METHODS: The authors retrospectively analyzed a cohort of patients with CNs treated with SRS at 10 centers between 1994 and 2018. Tumor recurrences were classified as local or distant. Adverse radiation effects (AREs) and the need for a CSF shunt were also evaluated. RESULTS: The study cohort comprised 60 patients (median age 30 years), 92% of whom had undergone prior resection or biopsy and 8% received their diagnosis based on imaging alone. The median tumor volume and margin dose were 5.9 cm ³ and 13 Gy, respectively. After a median clinical follow-up of 61 months, post-SRS tumor recurrence occurred in 8 patients (13%). The 5- and 10-year local tumor control rates were 93% and 87%, respectively. The 5- and 10-year progression-free survival rates were 89% and 80%, respectively. AREs were observed in 4 patients (7%), but only 1 was symptomatic (2%). Two patients underwent post-SRS tumor resection (3%). Prior radiotherapy was a predictor of distant tumor recurrence (p = 0.044). Larger tumor volume was associated with pre-SRS shunt surgery (p = 0.022). CONCLUSIONS: Treatment of appropriately selected CNs with SRS achieves good tumor control rates with a reasonable complication profile. Distant tumor recurrence and dissemination were observed in a small proportion of patients, which underscores the importance of close post-SRS surveillance of CN patients. Patients with larger CNs are more likely to require shunt surgery before SRS.

Objective Meningiomas are the second most common tumors in neurofibromatosis type 2 (NF-2). Microsurgery is challenging in NF-2 patients presenting with skull base meningiomas due to the intrinsic risks and need for multiple interventions over time. We analyzed treatment outcomes and complications after primary Gamma Knife radiosurgery (GKRS) to delineate its role in the management of these tumors. Methods An international multicenter retrospective study approved by the International Radiosurgery Research Foundation was performed. NF-2 patients with at least one growing and/or symptomatic skull base meningioma and 6-month follow-up after primary GKRS were included. Clinical and radiosurgical parameters were recorded for analysis. Results In total, 22 NF-2 patients with 54 skull base meningiomas receiving GKRS as primary treatment met inclusion criteria. Median age at GKRS was 38 years (10–79 years). Most lesions were located in the posterior fossa (55.6%). Actuarial progression free survival (PFS) rates were 98.1% at 2 years and 90.0% at 5 and 10 years. The median follow-up time after initial GKRS was 5.0 years (0.6–25.5 years). Tumor volume at GKRS was a predictor of tumor control. Lesions >5.5 cc presented higher chances to progress after radiosurgery (p = 0.043). Three patients (13.64%) developed adverse radiation effects. No malignant transformation or death due to meningioma or radiosurgery was reported. Conclusions GKRS is effective and safe in the management of skull base meningiomas in NF-2 patients. Tumor volume deserve greater relevance during clinical decision-making regarding the most appropriate time to treat. GKRS offers a minimally invasive approach of particular interest in this specific group of patients.