Tubular retractors in neuro-oncological surgery: a systematic review and meta-analysis

Neuro-oncological surgery necessitates a careful balance between maximising tumour resection whilst minimising damage to healthy brain parenchyma. Tubular retractors represent an emerging tool proposed to facilitate in the optimisation of this onco-functional balance. The objective was to evaluate the evidence regarding tubular retractors in neuro-oncological surgery. A systematic review and meta-analysis was performed. Studies reporting on surgical outcomes of tubular retractors in adult neuro-oncological cases were eligible. Medline, Embase, Cochrane Library, ClinicalTrials.gov, and ICTRP were searched to 14th July 2024. Duplicate title/abstract screening, data extraction, and risk of bias assessments were conducted. Prevalence of gross total resection (GTR) and complications were calculated using random effects models. 49 studies were included in the final analysis with a total of 684 patients. Combined pooled prevalence for GTR was 76% (95% CI: 67-85%), whilst for complications was 14% (95% CI: 8-20%). GTR rate by tumour histology was: 52% for gliomas (95% CI: 41-62%), 80% for metastases (95% CI: 65-92%), and 100% for colloid cysts (95% CI: 99-100%). Complication rate by tumour histology was: 16% for gliomas (95% CI: 5-30%), 12% for metastases (95% CI: 1-28%), and 16% for colloid cysts (95% CI: 8-24%). There was no significant difference between tubular retractor brands and GTR or complication rate (p > 0.05). Despite the mounting interest regarding the utility of tubular retractors in neuro-oncological surgery, the current evidence remains largely in the form of case series. Prospective studies with greater sample sizes, longer follow-up, and direct comparison to conventional retraction are now needed.