Navigated robotic-arm-assisted hybrid multi-portal endoscopic fenestration of a thoracic intradural arachnoid cyst: a technical case report

Achoimre

Abstract Endoscopic treatment of spinal intradural lesions is technically demanding because bimanual manipulation, irrigation control, neural protection, and dural closure are constrained. A 44-year-old woman with myelopathy from a dorsal T4–T10 intradural arachnoid cyst underwent endoscopic fenestration at T4/5. The hybrid multi-portal technique combined unilateral biportal-style exposure, a uniportal working-channel endoscope, intraoperative navigation, and robotic-arm camera stabilization. An accessory portal enabled bimanual intradural manipulation. Irrigation pressure was reduced after durotomy, and the dura was closed with sutures and clips reinforced by sealants. Day 1 magnetic resonance imaging confirmed cord decompression, and lower-limb sensory and bladder symptoms had resolved at 6 weeks. To our knowledge, this is the first reported navigated robotic-arm-assisted hybrid multi-portal endoscopic fenestration of a thoracic intradural arachnoid cyst. This single case demonstrates technical feasibility but not superiority over open or microscopic surgery.