ABSTRACT
One of the most challenging topics for surgeons, pathologists and radiologists is congenital anomalies of the branchial apparatus that include fistulas, sinuses, cysts, and temporal bone anomalies. The aim of the study was to describe primarily the CT features of different abnormalities that are secondary to anomalous embryogenesis of the branchial apparatus with surgical and pathological correlation. This study included 30 patients with branchial apparatus anomalies, all evaluated clinically and radiologically with correlation of the imaging findings with the surgical and pathological results. Thirteen patients had first branchial apparatus anomalies; namely five classic first branchial apparatus anomalies, and eight temporal bone anomalies. Classic first branchial apparatus anomalies included two intra-parotid cysts, one intra-parotid sinus and two anterior triangle cysts. Temporal bone anomalies included three isolated external aural atresias, one isolated middle ear cleft anomaly, and four combined external auditory canal and middle ear cleft anomalies. Fifteen patients had second branchial apparatus anomalies; namely eight cysts, four sinuses and three fistulas. Only two third branchial apparatus anomalies were encountered including one cyst and one sinus. The anatomic location of different branchial anomalies was described in reference to their embryonic origin. Of the 13 branchial cysts included in this study, nine displayed well defined borders with fluid attenuation, and four displayed ill defined borders with heterogeneous mixed attenuation; correlated with infective and haemorrhagic changes. Three infected cysts displayed marginal enhancement. Magnetic resonance imaging was performed for eight branchial cysts with post-Gd acquisitions obtained for five of the cysts; MR imaging features matched the nature of the cysts. CT and MR imaging are crucial in the assessment of branchial apparatus anomalies to provide the surgeon with a detailed "road map" stressing the relationship of the lesion to critical neck structures