# Case Report: Endoscopic dual-port surgery via the previous resection cavity for recurrent glioblastoma

## TL;DR

A new minimally invasive endoscopic surgery method is demonstrated for removing recurrent brain tumors using a previous surgical cavity.

## Contribution

The paper introduces a novel multi-port endoscopic approach for recurrent glioblastoma using a pre-existing resection cavity.

## Key findings

- A multi-port endoscopic resection was successfully performed in a patient with recurrent glioblastoma.
- The procedure used a pre-existing cavity to avoid additional brain tissue trauma.
- The approach allowed bimanual manipulation and achieved near-total tumor removal.

## Abstract

Although endoscopic techniques have become increasingly common in neurosurgery, true multi-port surgeries for intracranial lesions remain rare. Unlike laparoscopic or thoracoscopic procedures, intracranial surgery often requires traversal of normal brain parenchyma, limiting the creation of multiple access routes. However, after resection of intraparenchymal tumors, a postoperative cavity frequently remains and may serve as a potential working space for endoscopic manipulation. The feasibility of using such cavities for multi-port endoscopic tumor resection has not yet been established.

A 72-year-old man had previously undergone gross total resection of a contrast-enhanced lesion, followed by radiochemotherapy for a right frontal glioblastoma. Ten months later, a small, locally recurrent enhancing lesion developed along the posterior wall of the resection cavity. Given the patient's advanced age, comorbid diabetes mellitus, and the superficial location of recurrence, a minimally invasive multi-port endoscopic resection was planned. Limited reopening of the original skin incision was performed without removal of the bone flap. Two ports were created: one at the edge of the craniotomy and another through a 5-mm hole in the bone flap directly above the resection cavity. Tumor resection was performed under endoscopic visualization using an ultrasonic aspirator with real-time neuronavigation guidance. The multi-port configuration enabled stress-free bimanual manipulation without instrument interference. Near-total resection was achieved, with a residual enhancing tumor <1 cm in size. The postoperative course was uneventful.

This case demonstrates the feasibility of a minimally invasive multi-port endoscopic approach utilizing a pre-existing resection cavity for recurrent intracranial lesions. When a superficial and accessible postoperative cavity is present, this strategy may reduce surgical invasiveness and wound-related complications while providing a favorable operative environment.