Microsurgical resection of an enlarging lateral pontomedullary cavernous malformation.

The extended retrosigmoid approach provides an excellent corridor to the lateral aspect of the pontomedullary junction (PMJ).1,2 This video demonstrates a microsurgical resection of a progressive enlarging cavernous malformation (CM) of the PMJ. The patient is a 33-year-old woman with progressive symptoms, including right facial droop, left hemianesthesia, diplopia, and nystagmus. The patient underwent a right extended retrosigmoid approach with intraoperative neuronavigation and neuromonitoring. Lower cranial nerve dissection allowed access to the lateral PMJ. A longitudinal corticotomy was performed above the glossopharyngeal. The CM was removed in a piecemeal fashion. Postoperative MRI confirmed gross-total resection and the patient remained neurologically stable. The video can be found here: https://youtu.be/K_TtiTo1RsQ.