The use of magnetic resonance angiography prior to pharyngeal flap surgery in patients with velocardiofacial syndrome.

Twenty consecutive patients with velocardiofacial syndrome underwent magnetic resonance angiography (MRA) to determine if abnormalities of the neck arteries would contraindicate pharyngeal flap surgery. All 20 patients were found to have anomalies to the carotid arteries, vertebral arteries, medially placed internal carotids, low carotid bifurcations, and tortuous or kinked internal carotids. The internal carotids were found to be almost directly under the mucous membrane of the pharynx in two patients. In these two patients, the arteries were close to the pharyngeal midline at the base of the first cervical vertebra and might easily be severed during the raising of a pharyngeal flap. Hypoplastic vertebral arteries also were found. One patient had an extra neck vessel. The anomalies of the internal carotids did not have a strong correlation with endoscopically observed pulsations in the position affected the location of the internal carotids did not have a strong posterior pharyngeal wall. It also was found that head position affected the location of the internal carotid arteries when they were located close to the pharyngeal mucous membrane. The information provided in the MRA studies allowed assessment of the arterial anomalies in relation to the flap donor site so that the patients in the sample who underwent pharyngeal flap surgery using a short superiorly based flap had no major bleeding complications.