The natural history of cerebral infundibula: A retrospective cohort study.

Objective: Debate exists regarding the true pathogenicity of cerebral infundibula (CI). Pre-aneurysmal lesions and benign anatomical variants have both been proposed. In this study, we present the largest single cohort series on the natural history of CI. Methods: Retrospective review of prospective surveillance of 420 CI was undertaken in a single tertiary cerebrovascular centre. All CI diagnosed by a neuroradiologist, diagnosed on either a Magnetic resonance angiography (MRA), Computed tomography angiography (CTA) or Digital subtraction angiography (DSA) were eligible for inclusion. Imaging and demographic characteristics were recorded at baseline. CI growth and aneurysm transformation were the outcomes of interest. Groupwise comparison was conducted via Fischer exact testing. Kaplan Meir curves and Cox proportional hazard ratios were used to assess variables of interest with respect to time on surveillance. Results: 402 patients with 420 CI were surveyed over 2418 infundibula-years. Eleven CI (2.62%) grew on surveillance, and three (0.7%) transformed into aneurysms. Median time to growth was 85 months (36-263) and median time to aneurysm transformation was 112 months (96-142). Of the CI that grew, male sex and CI >2 mm at diagnosis were significant predictors of growth (all p<0.05). Of the CI that grew in surveillance, 2/11 (18.2%) transformed into aneurysms (p=0.001). Aneurysm transformation occurred at a rate of 1.27 per 1000 infundibula years. CI growth on surveillance (p= 0.00016) and size at diagnosis (p=0.038) remained significant predictors of aneurysm transformation on Kaplan Meir curves. Conclusions: The transformation of a CI to an aneurysm occurs at a low rate. A history of growth on surveillance imaging represents significant risk for aneurysm transformation.

Incidence of hydrocephalus following decompressive craniectomy for ischaemic stroke: A systematic review and meta-analysis.

OBJECTIVE: Decompressive craniectomy (DC) following malignant ischaemic stroke is a potentially life-saving procedure. Event rates of ventriculomegaly following DC performed in this setting remain poorly defined. Accordingly, we performed a systematic review to determine the incidence of hydrocephalus and the need for cerebrospinal fluid (CSF) diversion following DC for malignant stroke. METHODS: MEDLINE, EMBASE and Cochrane libraries were searched from database inception to 17 July 2021. Our search strategy consisted of "Decompressive Craniectomy", AND "Ischaemic stroke", AND "Hydrocephalus", along with synonyms. Through screening abstracts and then full texts, studies reporting on rates of ventriculomegaly following DC to treat ischaemic stroke were included for analysis. Event rates were calculated for both of these outcomes. A risk of bias assessment was performed to determine the quality of the included studies. RESULTS: From an initial 1117 articles, 12 were included following full-text screening. All were of retrospective design. The 12 included studies reported on 677 patients, with the proportion experiencing hydrocephalus/ventriculomegaly being 0.38 (95% CI: 0.24, 0.53). Ten studies incorporating 523 patients provided data on the need for permanent CSF diversion, with 0.10 (95% CI: 0.07, 0.13) requiring a shunt. The included studies were overall of high methodological quality and rigour. CONCLUSION: Though hydrocephalus is relatively common following DC in this clinical setting, only a minority of patients are deemed to require permanent CSF diversion. Clinicians should be aware of the incidence of this complication and counsel patients and families appropriately.

An Australian Response to the COVID-19 Pandemic and Its Implications on the Practice of Neurosurgery.

OBJECTIVE: This study was designed to assess the impact of public health policy in Australia in response to the coronavirus disease identified in 2019 (COVID-19) pandemic on the delivery of neurosurgical services. Being essential services, we postulated that there would not be a decrease in elective and emergency neurosurgical presentations and surgeries. METHODS: This is a prospective, observational, epidemiologic study in strict adherence to the "STROBE" (Strengthening The Reporting of OBservational studies in Epidemiology) guidelines. It is a cross-sectional, multicentric study involving 5 tertiary neurosurgical centers to capture all public neurosurgical admissions in Queensland during the past 3 months (February-April, 2020) of significant public health policy changes to combat COVID-19. RESULTS: An analysis of the 1298 admissions for the Queensland population of 5.07 million Australians demonstrated a decrease in the number of elective and emergency admissions. The decline in elective admissions, particularly degenerative spine, benign neoplasms, and vascular pathologies, was a direct response of government strategy to curb activity to urgent surgical interventions only. Moreover, a trend toward fewer emergency admissions was also noted, partly explained by less trauma and also a decline in vascular pathologies including subarachnoid hemorrhage. CONCLUSIONS: In comparison with Europe and North America, this study demonstrates the impact of proactive public health measures in Australia that successfully flattened the COVID-19 curve while facilitating ongoing care of acutely unwell neurosurgical patients.