MR IMAGED NEUROVASCULAR RELATIONSHIPS AT THE CEREBELLOPONTINE ANGLE

Improvements in MR imaging techniques allow visualisation of the anato my of the cerebellopontine angle (CPA) in increasingly accurate detail , revealing the complex interrelationship of the neurovascular structu res in this region. We wished to assess whether vessels and vascular l oops intimately associated with cranial nerves VII and VIII, correspon ded. to any abnormality or symptom pattern, and thus had any clinical significance. The MR scans of 108 patients were retrospectively review ed and the imaging status of VII, VIII, the vessels, presence of vascu lar loops and their relationship to the nerves, coded and recorded. Th e patients' records were independently reviewed and the presence and ' sidedness' of asymmetrical hearing loss, tinnitus, vertigo, and the re sults of caloric and brain stem evoked responses recorded. The vessels were closely associated with VII and VIII in over 30% of this sample with vascular loops imaged in 21% of patients, and clearly imaged ente ring the IAM in 7% of both right and left CPAs studied. There was no s tatistically significant relationship demonstrated between the proximi ty of the vessels, or vascular loops, to the nerves and a symptom, or symptom pattern. These findings should be considered a normal variant on MR scanning.