RESUMO
First branchial cleft anomalies are embryological defect account for 8-10% of all branchial cleft defects. Approximately 17% of all Paediatric cervical masses are due to branchial anomalies. Despite of the fact that these anomalies are benign, secondary infection, positional effect and complication of treatment like surgery account for morbidity. Here one such case of 30 years old lady who presented to us with one discharging sinus in the floor of the right external auditory canal with a swelling in the upper neck for about 20 years. On examination showed one discharging sinus opening in the floor of right external auditory canal (EAC) and a cystic swelling in upper neck between sternomastoid and mandible. While compression over the swelling cheesy discharge comes out from EAC. MRI showed oval shaped fluid signal intensity lesion measuring about 4 × 2.1 × 1.6cm in right infra auricular region with slit like curvilinear tract about 10mm extending from upper part of the lesion opening into the antero-inferior part of external auditory canal at the junction of bony and cartilaginous part. Histopathology report showed a cyst lined by stratified squamous epithelium; wall is composed of fibrocollagenous tissue with mucous gland. The wall is densely infiltrated with lymphocytes forming lymphoid follicles at places. This paper presents a case report of collaural sinus from Otology unit, Department of Otolaryngology-Head & Neck Surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh.