Paroxysmal otalgia due to compression of the intermediate nerve: a distinct syndrome of neurovascular conflict confirmed by neuroimaging. Case report.

Abstract

The authors present the case of a 52-year-old female patient with a 6-year history of intractable paroxysmal otalgia. Preoperative magnetic resonance (MR) angiography demonstrated an anterior inferior cerebellar artery loop compressing the intermediate nerve in the seventh/eighth cranial nerve complex inside the internal auditory canal. The pain resolved completely after a microvascular decompression via a retromastoid craniotomy. To the best of the authors' knowledge, the combined neuroimaging and intraoperative findings of this case provide a unique demonstration that vascular compression of the intermediate nerve can be the exclusive cause of paroxysmal otalgia. Magnetic resonance imaging and MR angiography can establish the causative mechanism and distinguish this otalgia due to vascular compression of the intermediate nerve from other pain syndromes that are designated as geniculate neuralgia (GN). The present case indicates that intermediate nerve neuralgia is a distinct syndrome of neurovascular conflict and a variant of GN. The causative classification of GN should be reexamined with the use of advanced MR imaging.