Preoperative Assessment of Microvascular Compression of Cranial Nerve IX and X Using 3D Fast Imaging Employing Steady-state Acquisition Magnetic Resonance Imaging in Glossopharyngeal Neuralgia

Abstract

We report a case of glossopharyngeal neuralgia associated with a vascular loop of the postero-inferior cerebellar artery, precisely diagnosed by preoperative magnetic resonance imaging (MRI) with a sequence of 3-dimensional fast imaging employing steady-state acquisition (3D-FIESTA). A 44-year old man experienced paroxysmal and excruciating pain, starting in the left tongue and descending to mandibular angle. Preoperative 3D-FIESTA-MRI delineated a small vascular loop compressing the vago-glossopharyngeal nerve at its cisternal portion. The patient underwent a microvascular decompression surgery. Intraoperative inspection revealed that the glossopharyngeal nerve root was in contact with a small arterial loop at its cisternal portion and was deformed as demonstrated by preoperative 3D-FIESTA-MRI. At the operation, we adopted the method of repositioning the offending loop of the posteroinferior cerebellar artery by lifting and attaching it to the nearby dura of the petrous bone with glue. The patient's neuralgia resolved immediately after the operation. 3D-FIESTA may be a useful method for visualization of microvascular compression of glossopharyngeal nerve in this relatively rare condition.