Background: Postoperative cerebrospinal fluid (CSF) leak is a major concern after posterior fossa surgery with significant clinical implications. It has been postulated that replacing the bone flap, performing a craniotomy, would reinforce the surgical closure and decrease rates of CSF leak. This systematic review and meta-analysis compared the rate of CSF leak after posterior fossa craniotomies versus craniectomies. Methods: Three databases were searched for English studies comparing the primary outcome, rate of CSF leak, after adult posterior fossa craniotomies versus craniectomies. Secondary outcomes included the rate of postoperative pseudomeningocele formation, CSF leak and pseudomeningocele formation, CSF diversion, revision surgery, and infection. Pooled estimates and relative risks for dichotomous outcomes were calculated using Review Manager 5.4, with corresponding 95% confidence intervals (CIs). Results: A total of 1250 patients (635 craniotomies and 615 craniectomies), from nine studies, were included in the final analysis. Even though rates of CSF leak favored craniotomies, the difference did not reach statistical significance in our pooled analysis (Risk Ratio: 0.71, 95% Confidence Interval: 0.45-1.14, p-value = 0.15, Heterogeneity I-squared = 0%). On the other hand, comparing the rates of pseudomeningocele formation and CSF leak, as a combined outcome, or pseudomeningocele formation only showed a significant difference favoring craniotomies. The quality of evidence in this meta-analysis was graded as having a high risk of bias based on the risk of bias in non-randomized studies - of exposure criteria. Conclusion: Based on evidence with high risk of bias, rates of postoperative CSF leak and pseudomeningocele formation favored posterior fossa craniotomies over craniectomies. Further research with more robust methodology is required to validate these findings.

Background: Penetrating head injury secondary to crossbows is a rare encounter in neurosurgical practice with only few cases reported in the literature. Methods: Chart review and literature review. Results: A 31-year-old man with a previous psychiatric history sustained a self-inflicted injury using a crossbow he bought from a department store. The patient arrived neurologically intact. He was not able to verbalize due to jaw fixation with the arrow. The trajectory of the object showed an entry point at the floor of the oral cavity and an exit through the calvarium just off the midline. The oral and nasal cavities, along with the palate and the skull base, and the left frontal lobe were all breached (figure). No vascular injury was identified on imaging (figure). The arrow was surgically removed in the operating room after establishing an elective surgical airway. A planned delayed CSF leak repair was performed. The patient made a substantial recovery and was discharged home in good status. Conclusions: - Multidisciplinary team is key.Vascular imaging should be done pre and post-intervention.Surgical approach is determined by the trajectory.Psychiatric illness and access to weapons are major risk factors.Elective surgical airway might be indicated.