Clinical Characteristics of a Rare Type I Congenital First Branchial Cleft Anomaly With Native Sinus Tract

We present an unusual type I congenital first branchial cleft anomaly (CFBCA) characterized by a distinct sinus tract in the superior wall of the cartilaginous external auditory canal (EAC), classified as the sinus variant of type I congenital first branchial cleft anomalies (CFBCAs). This study aims to characterize its distinctive clinical features and present management approaches for this rare entity.

Medical records of patients undergoing excision for sinus variant of type I CFBCAs between January 2007 and September 2023 (a 16-y period) were retrospectively analyzed. Clinical characteristics, therapeutic interventions, histopathologic diagnoses, and long-term outcomes were systematically catalogued.

The sinus variant of type I CFBCAs is a rare manifestation of CFBCAs, accounting for 11 of 188 cases (5.9%) in our series. Cardinal clinical features included recurrent periauricular inflammation (9/11 cases, 81.8%), with all cases demonstrating a characteristic concealed sinus orifice at the superior cartilaginous EAC (11/11 cases, 100%). All patients (11/11 cases, 100%) were initially misdiagnosed as lymphadenitis, epidermal cysts, or localized infections. The concealed sinus orifices at the superior cartilaginous EAC were frequently overlooked, with definitive diagnosis established by visual inspection in only 3 patients (3/11 cases, 27.3%). In the remaining 8 patients (8/11 cases, 72.7%), occult sinus orifices were identified through combined palpation and visual inspection. All lesions originated exclusively from the superior cartilaginous EAC (11/11 cases, 100%) and maintained a relative simple relationship with the facial nerve trunk (11/11 cases, 100%). Complete surgical excision of the sinus tract along with any adherent periauricular cysts was determined to be the optimal treatment approach.

Clinicians should maintain a high index of suspicion for the sinus variant of type I CFBCAs when evaluating pediatric patients with recurrent preauricular inflammation. The identification of a characteristic sinus orifice at the superior cartilaginous EAC during focused examination is diagnostic.

Level 4.