An Unusual Case of Bilateral First Branchial Cleft Anomaly: A Case Report with Review of Literature

Abstract

We report a case of 32 year old male who presented to us with first branchial cleft anomalies on both sides with discharging cutaneous openings on the right side; and cystic swelling on the left side. High index of suspicion is required in such congenital cysts. Surgical exploration and excision is the definitive treatment of a collaural fistula.

Introduction

In the 4th week of human embryological development, six branchial arches appear as bar in the wall of pharynx which will form the future lower face and neck [1]. The external ear canal develops form dorsal part of the first branchial groove. The ventral part of first branchial groove normally disappears but may persist as a pre auricular sinus, or a collaural fistula, and it accounts for < 8% of all branchial cleft abnormalities [2, 3], Rarely 2–3% of these anomalies have a bilateral presentation [4]. A collaural fistula is the least common of the first branchial cleft anomalies [2]. We report a case of bilateral first branchial cleft anomaly presented as collaural fistula on right side and cyst on left side.

Case Report

A 32 year old male presented with history of discharging cutaneous opening on right side and cystic swelling on left side behind ear since 8 years. There was history of incision and drainage done 8 years back to both swellings located behind ear which resolved only to reappear after 2 months. Local examination revealed a fistulous opening and swelling on right side of the face, 2 cm above angle of mandible, extending superiorly to mid-point of attachment of pinna, inferiorly to lower border of pinna, anteriorly till post aural groove and posteriorly till mastoid prominence (Fig. 1). Another swelling was noted on left side of the face, 2 cm above angle of mandible, extending superiorly to upper attachment of pinna, inferiorly to lower border of pinna. Swelling was fluctuant, and firm to cystic in consistency (Fig. 1). Both swellings had scar mark indicating previous surgery. The external auditory canal (EAC) both sides were normal on examination and no opening seen. Contrast enhanced magnetic resonance imaging neck revealed bilateral well defined lobulated post auricular cystic lesions noted in Parotid spaces, measuring 2 × 1.6 × 2.7 cm on right side and 1.8 × 4.0 × 2.8 cm on left side. The lesion on the left side was intra parotid and showed thin regular non enhancing walls with fluid intensity contents. A tiny out pouching from cyst was seen communicating with external auditory canal (EAC). Surrounding parotid appeared normal. Bulk of the lesion on right side was postero lateral to parotid reaching up to skin and showed thick, irregular enhancing walls with mixed intensity contents within. A tiny out pouching from cyst was seen to be communicating with external auditory canal (EAC). Impression on contrast enhanced magnetic resonance imaging neck revealed bilateral first branchial anomaly (Cysts) with possible infection on right side (Fig. 2). Considering these clinical and radiological findings; diagnosis of right collaural fistula and left collaural cyst was made. The patient was planned excision of both tracts under general anaesthesia. Elliptical incision was given on right side around fistula extending into pre auricular region. Fistula was found superficial to facial nerve. Careful dissection done, fistula found superficial to right EAC, fistula was removed along with part of right EAC cartilage (Fig. 3). Modified Blair’s incision is given on left side of face and flap elevated. Cyst found to be contained in left superficial lobe of parotid, found reaching up to left EAC. Cyst carefully dissected preserving branches of Facial nerve (Fig. 4). The facial nerve function was normal in all branches. The patient is under regular follow-up and symptom-free. Histopathological examination showed keratinising stratified squamous epithelium overlying fibro cartilaginous cyst wall. Right branchial cyst showed dense chronic granulation tissue within the cyst wall, consistent with bilateral branchial cleft cyst. (Figure 5).

Fig. 1.

Right branchial fistula and left branchial cyst

Fig. 2.

Contrast enhanced MRI neck shows bilateral first branchial anomaly (Cysts). Arrow points towards right and left branchial anomaly

Fig. 3.

Right branchial fistula dissection

Fig. 4.

Left branchial cyst dissection

Fig. 5.

Cyst lined by keratinising stratified squamous epithelium overlying fibro cartilaginous cyst wall

Discussion

More than 200 cases of first branchial cleft anomalies are reported in the literature. First branchial cleft anomalies accounts for less than 8% of all branchial abnormalities [2, 3]. Only 2–3% of these first branchial cleft anomalies have a bilateral presentation [4], with the rate of bilateral anomalies seem higher in familial cases. The peculiarity of our case is bilateral presentation of first branchial anomaly, where majority of first branchial anomalies are unilateral in presentation. Embryological anomalies of the first branchial cleft usually present as cysts, swellings or fistulas in the pre auricular or post auricular area or high in the neck, which may become infected. Collaural fistula is the remnant of embryonic development and results from failure of ventral part of the first branchial cleft to involute [5]. It is epithelial lined tract, and it runs from the bony cartilaginous junction of external ear canal down into the neck where it opens at a point between the angle of mandible and the sternocleidomastoid. The common sites of external opening of fistulas and sinuses are the EAC (40%), upper neck (32.5%), concha (20%), and posterior auricular area (7.5%) whereas in our case external opening was present 2 cm above angle of mandible on the right side suggesting collaural fistula and cystic swelling was present 2 cm above angle of mandible on the left side suggesting collaural cyst. The course of fistulous tracts relative to the facial nerve can be superficial (41%), deep (37%), or between the branches (22%) [6, 7]. The close relationship of first branchial cleft anomalies to the facial nerve results in frequent complications from surgical treatment. The risk of facial nerve injury increases in patients who have had multiple infections or surgical procedures. In our case right branchial fistula was superficial to facial nerve; left branchial cyst was lateral to facial nerve.

Classification of first branchial cleft anomalies is on the basis of tissue type lining the tract: Type I contains ectoderm, whereas Type II has both ectoderm and mesoderm [8, 9]. On the basis of location of external opening: Type I is adjacent to the EAC, whereas Type II is may pass through the parotid gland in a variable relation to the facial nerve and the fistulous tract may end either in the cartilaginous EAC or extend to the face or upper neck or at the angle of the mandible. According to this classification, either type is regarded as duplication of either the membranous (Type I) or both the membranous and cartilaginous (Type II) portions of the EAC. In our study based on location, Type I was found on right side and Type II was found on left side. In our case right branchial fistula was located postero lateral to parotid gland, whereas left branchial cyst was contained in superficial lobe of parotid.

First branchial cleft anomalies usually come to the clinician’s attention because of an external opening or recurrent infections or swelling as seen in our case. Diagnosis of collaural fistula is achieved mainly through careful physical examination of both the neck and the EAC. First branchial cleft anomalies are seen approximately twice as often in female (69%) as in male (31%). The external opening of fistulas occurs more frequently on the left side (64%); whereas in our case it was on right side [10]. The study by Triglia et al. showed fistula opening in EAM in 44% of the patients and asymptomatic membranous attachment between the floor of the EAC and the tympanic membrane was found in 10% of the cases [11].

Radiological examinations can be helpful diagnostically, to determine the typical anatomical localization, the extent, the size, and the relationship of the lesions to surrounding structures. The magnetic resonance imaging allows assessment of the extent of the anomaly, especially in the parotid area and facial nerve branching pattern [11].

Surgical excision of the entire fistulous tract with resection of a small amount of skin and cartilage within the EAM is the treatments of choice [12]. To avoid damage to the facial nerve a conservative superficial parotidectomy with full exposure of the facial nerve is required. The incidence of temporary facial nerve palsy was 21% in the patients in whom the nerve was identified and 29% in the patients in whom the facial nerve was not identified. The incidence of permanent facial paralysis was 1% in the patients in whom the nerve was identified and 12% in the patients in whom the nerve was not identified [3].

Conclusion

Cysts, sinuses or fistulous tracts which are pre-auricular or post-auricular or high in the neck, may represent a branchial cleft anomaly. The usefulness of various anatomical and histological classifications is limited and it is often difficult and confusing trying to correlate the clinical picture with various classifications. Radiological evaluation plays an important role in identifying such anomalies. The conventional operation for first branchial cleft fistula is highly complicated, involves complete excision of fistulous tract and facial nerve palsy is a frequent complication.

Funding

Nil.

Compliance with Ethical Standards

Conflict of interest

None.

Informed Consent

Taken from patient.

Ethical Statement

Permission taken from institutional ethical committee for doing this study.