Materials and methods Registration and reporting standardsWe performed this systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Appendix 1) [53]. The study protocol is published on PROSPERO (CRD 42,021,285,118). Search strategyWe performed a comprehensive literature search (Appendix 2) using OVID Medline, EMBASE, ClinicalTrials.gov, OpenGrey and Cochrane Library from 1st January 1989 to 1st September 2021 for relevant articles. We reviewed the bibliographies of included studies for further articles meeting our eligibility criteria. Eligibility criteriaWe sought randomised trials and observational cohort studies, published in English in peer-reviewed journals reporting 20 + adult (18 +) patients with AVMs, diagnosed by MRI or histopathological examination, treated with single-session GKRS. We included studies describing all the following patient and AVM characteristics: (1) median (or mean) margin dose, (2) AVM volume (or maximum nidus diameter), (3) clinical presentation, (4) AVM Spetzler-Martin grades. We included studies reporting all the following clinical and radiological outcomes, with a minimum follow-up period of 12 months following GKRS: (1) complete nidus obliteration rate (angiography or angiography/MRI-confirmed), (2) post-GKRS ICH, (3) RICs or adverse radiation effects (ARE).

BACKGROUND:Spontaneous spinal epidural hematoma (SSEH) is a rare pathology, which carries a significant morbidity.OBJECTIVE:To review our institutional experience of surgically managed patients with SSEH, seeking to better understand clinical prognostic factors related to postoperative outcomes and thereby improve counseling of patients before treatment.METHODS:All patients who underwent surgical management of SSEH between September 2011 and 2021. Baseline and postoperative clinical and radiological characteristics are presented, including the American Spinal Injury Association grade (ASIA). Statistical analyses were performed using Stata 13.1.RESULTS:Eighteen patients were identified in total (11 male patients and 7 female patients) with a median age of 59.5 (range 3-83) years. The most common spinal region affected was cervicothoracic (33.3%). Limb weakness (94.4%) and urinary dysfunction (83.3%) represented the most common presenting symptoms. Preoperatively, the presence of spinal cord edema on imaging was associated with worse preoperative Medical Research Council (MRC) grade (P = .033), female sex was associated with preserved saddle sensation (P = .04), and patients receiving antiplatelet medication were associated with a higher risk of preoperative axial back pain (P = .005). Higher postoperative MRC grade was associated with higher preoperative ASIA (P = .012) and MRC grade (P = .005), and preservation of saddle sensation (P = .018). Postoperative improvements in axial back pain were associated with higher preoperative ASIA grade (P = .035) and anticoagulation treatment (P = .029).CONCLUSION:Neurosurgical intervention for SSEH yields positive outcomes and benefits patients. Patients with higher preoperative ASIA, MRC grade, and those presenting with preserved saddle sensation may experience further improved clinical outcomes after intervention.

Objectives: For the diagnosis of subarachnoid haemorrhage (SAH), the presence of cerebrospinal fluid (CSF) xanthochromia is still considered the gold standard for patients with a thunderclap headache, in the absence of blood on brain CT scan. However, a traumatic lumbar puncture (LP) typically results in high concentrations of oxyhaemoglobin in CSF, impairing the detection of xanthochromia and preventing the reliable exclusion of SAH. In this context, the value of a repeat lumbar puncture has not yet been described. Materials and methods: A retrospective case series of suspected SAH patients, with a negative CT scan and initial traumatic LP, managed with a repeat LP to assess for CSF xanthochromia. Clinical notes, laboratory and imaging results were reviewed. Results: Between August 2011 and January 2020, 31 patients with suspected SAH were referred to our neurosurgical unit following negative CT and traumatic LP. A repeat LP was performed in 7 of the 31 patients, 2.4 days (±0.79 SD) after the first traumatic LP. CSF spectrophotometry analysis from repeated LP in all 7 patients was negative for xanthochromia. No adverse clinical events were recorded on average 18 months following discharge. Conclusion: A repeat LP performed following a traumatic tap can still yield xanthochromia-negative CSF, thereby, excluding SAH, avoiding unnecessary invasive angiography and overall promoting the safer management of these patients.