Roman BOSNJAK: Endoscopic MVD in Trigeminal Neuralgia

This video is about pure endoscopic microvascular decompression of trigeminal nerve.

Short attacks of lancinating electric like pain, triggers and evidence of neurovascular conflict in MRA imaging constitute basics for MVD indication.

Endoscope enables close, side and angled view and enhances identification of neurovascular conflict.

The patient is operated on in supine position, the head rotated to the contralateral side and slightly elevated. The endoscope was held by an assistant.

The 12-15 mm burrhole is drilled with a diamond ball exactly in the corner between transversus and sigmoid sinus. The blue lines at superior and lateral margins in the hole should be visible when dura is exposed. Two small triangular flaps are flipped up and lateral to expose cerebellar cortex in the angle between Transversus and Sigmoid sinus. With the use of cottonoid strip, the the cerebellum is gently pushed down and medially, exposing tentorium up and the corner between tentorium and posterior pyramidal wall. Once CSF is released, everything becomes easier and more spacious. Normal anatomy is then presented: internal auditory canal with seventh and eight nerve (and labyrinthine artery), sixth nerve entering Dorello’s canal, the petrous vein, trigeminal nerve from brainstem to the dural entrance (ostium) into cavum Meckeli. The fourth nerve floats along the tentorial margin. The axilla of the trigeminal nerve is explored first from inferior and superior aspect for any arterial, venous or arachnoid band contact with the nerve. The whole length of the nerve should be checked.

In this case, the conflict was found in the superior aspect of the nerve in a form of two parallel arteries, most probably from superior cerebellar artery. These were relocated and secured in new position away from the nerve with Tachosil and Teflon patch (not shown in this video).

Enjoy the anatomy.

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You may also see Neurosurgery: Trigeminal neuralgia - endoscope-assisted microvascular decompression - Dr. Bosnjak (April 2013)