Minimally Invasive Resection of Intra-axial Posterior Fossa Tumors Using Tubular Retractors

Objective: Posterior fossa tumor surgery is associated with a significant risk of complications, and the complications are typically more frequent compared with similar supratentorial surgeries. This study aimed to evaluate 1) the extent of resection and neurologic outcomes and 2) perioperative complications with use of minimally invasive approaches for intra-axial posterior fossa tumors from our case series. Methods: All consecutive patients who underwent nonbiopsy surgery of a posterior fossa tumor using tubular retractors and exoscopic visualization from January 2016 to May 2018 were prospectively identified and included. Results: During the reviewed period, 15 patients underwent resection of an intra-axial posterior fossa tumor. Eight (53%) patients were men, and the median age was 63.0 years (interquartile range: 45.0–67.5 years). The tumor was located in the cerebellar hemisphere in 11 (73%) cases, vermis in 3 (20%) cases, and middle cerebellar peduncle in 1 (7%) case. The median preoperative and postoperative lesion volumes were 21.6 cm³ (interquartile range: 10.1–33.0 cm³) and 0 cm³ (interquartile range: 0–1.2 cm³), respectively. The percent resection was 100% (92%-100%). Following surgery, 12 (80%) patients had improved and 3 (20%) patients had stable Karnofsky performance scale scores, whereas no patients had a decline in Karnofsky performance scale score postoperatively. No patients incurred other postoperative regional or medical complications. Conclusions: We demonstrated the possible efficacy of a minimally invasive approach with the use of tubular retractors and exoscopic visualization for resecting posterior fossa intra-axial tumors with relatively high efficacy and low morbidity.