Endoscopic criteria of offending vessel in neurovascular compression syndrome

Abstract

Abstract Objectives: The aim of this work was to detect the anatomical relationship criteria of the offending vessel with respect to the cranial nerve in neurovascular compression syndrome using the endoscopic-assisted minimally invasive retrosigmoid approach for microvascular decompression (MVD); these criteria help the surgeon to define the actual conflicting vessel during surgery for better results. Materials and method: Between 1994 and 2009, we have performed 782 cases of MVD surgeries using endoscopic-assisted minimally invasive retrosigmoid approach (453 MVD surgeries for hemifacial spasm, 269 for trigeminal neuralgia, 56 for tinnitus and vertigo, and four decompressions for glossopharyngeal neuralgia). During these surgeries we recorded the anatomical relationships between the offending vessel and the affected cranial nerve to detect the endoscopic criteria of the offending vessel. Results: There are certain criteria for the anatomical relationship between the offending vessel and affected cranial nerve; these criteria include common features such as a perpendicular contact between the vascular loop and the cranial nerve along two different perpendicular planes at its root exit zone, distortion of the nerve course, and distortion or compression of adjacent neural structures mainly brain stem. Other criteria include the vascular loop causing impression of the nerve or encircling the nerve causing reduction of its diameter. Conclusion: Certain criteria for the anatomical relationship between the offending vessel and the affected cranial nerve should be fulfilled to diagnose the actual conflicting vessel during MVD surgery in vascular compression syndrome using endoscopic-assisted minimally invasive retrosigmoid approach.