Precise cannulation of the foramen ovale in trigeminal neuralgia complicating osteogenesis imperfecta with basilar invagination: Technical case report

OBJECTIVE AND IMPORTANCE: Trigeminal neuralgia is a rave feature of basilar invagination, which is itself a complication of osteochondrodysplastic dis orders. Microvascular decompression is an unattractive option in medically refractory cases. The conventional percutaneous approach to the trigeminal ganglion is anatomically impossible because the foramen ovale points inferi orly and posteromedially. We report a new technique for image-guided trigem inal injection in a patient with basilar invagination complicating osteogen esis imperfecta. C CLINICAL PRESENTATION: A 26-year-otd woman with osteogenesis imperfecta pre sented with a 3-year history of typical left maxillary division trigeminal neuralgia, which was poorly controlled by carbamazepine at the maximum tole rated dose. She had obvious cranial deformities, left optic atrophy, delaye d left eye closure, tongue atrophy, but normal facial sensation and corneal reflexes. A computed tomographic scan and magnetic resonance imaging confi rmed severe basilar invagination. TECHNIQUE: Frameless stereotactic glycerol injection of the left trigeminal ganglion was performed under general anesthesia using the infrared-based E asyCuide Neuro system (Philips Medical Systems, Best, The Netherlands) with magnetic resonance imaging and computed tomographic registration. The disp laced and distorted left foramen ovale was cannulated via a true frameless stereotactic method with the trajectory determined by virtual pointer elong ation. The needle placement was confirmed with injection of contrast medium into the trigeminal cistern. The path needed to enter the foramen traverse d the right cheek, soft palate, and left tonsil. The patient went home pain -free with a preserved corneal reflex and no complications. CONCLUSION: Frameless stereotaxy allows customization to individual patient anatomy and may be adapted to a variety of percutaneous procedures used in areas where the anatomy is complex.