Microvascular decompression using vascular transposition and an extracranial self-locking knot: A technical note

Background: Microvascular decompression (MVD) is an established etiological treatment for neurovascular compression syndromes, particularly trigeminal neuralgia and hemifacial spasm. Classical techniques often rely on interposition materials; however, recurrence or persistent symptoms may be related to incomplete decompression, implant displacement, excessive material, granuloma formation, recurrent vascular compression, or arachnoid adhesions. Methods: We describe a technical modification of sling-assisted vascular transposition using an extracranial self-locking knot during MVD. In selected patients with neurovascular compression syndromes, including trigeminal neuralgia, hemifacial spasm, recurrent conflicts, or vertebrobasilar dolichoectasia, a standard retrosigmoid approach is performed. After complete release of the arachnoid and circumferential mobilization of the culprit vessel, a sling is fabricated using a suturable, non-absorbable dural substitute. First, an extracranial suture is placed through the dural analog, the mesh is fabricated beneath the vessel, and then the analog is anchored to the tentorium or the petrous dura mater depending on the desired vector. Final adjustment is achieved using an extracranial self-locking knot, which is advanced progressively until adequate decompression is obtained and then locked in position, avoiding deep intracranial knotting. Results: The technique was feasible and reproducible in our initial experience. To date, no complications attributable to the sling construct or extracranial locking mechanism have been observed. Conclusion: The extracranial self-locking knot is a simple technical modification for vascular transposition during MVD. It may facilitate reproducibility and standardization of vascular fixation, particularly in complex, recurrent, or dolichoectatic neurovascular conflicts.