The fourth branchial cleft deformity on the left anterior chest wall: a case report and literature review

To explore the main points of clinical treatment of fourth branchial cleft deformity in special positions and to provide a reference for clinical practice.

The clinical data of one case of a fourth branchial cleft deformity that occurred in the left anterior chest wall with a fistula below the clavicle are summarized and combined with a literature review.

The patient complained of repeated swelling and pain under the left anterior chest wall for 2 months. A 10 mm×10 mm fistula with yellow clear liquid exudate from the fistula was observed on the left side below the clavicle. A 20 mm×20 mm×10 mm swelling was immediately adjacent at the superficial cervicothoracic junction of the upper sternoclavicular joint, with no fluctuation and poor activity; this swelling produced slight pain upon pressing. Imaging examinations pointed to cystic lesions. The primary diagnosis was a fourth branchial deformity. A small amount of methylene blue was injected into the patient's subclavian fistula, and a supraclavicular T-shaped incision was made where the cyst contacted the fistula. By turning the flap, all the methylene blue-stained areas and adjacent submucosal tissues were exposed. During the operation, a mass was found on the sternum. The platysma was found deep in the notch, which was incised before excising the surrounding area. The pathological result is the fourth branchial cleft deformity. After 1 week and 3 months of follow-up, the patients had no discomfort and no recurrence. A review of the relevant literature shows that the fourth branchial cleft deformity is a congenital developmental abnormality that occurs in 1% of all branchial cleft deformity. It often presents as a fistula, cyst, or sinus tract and is anatomically located at the neck root and supravicular region. The fistula is close to the medial lower boundary of the sternocleidomastoid muscle. The diagnosis is often made based on its anatomical location, imaging examinations and, ultimately, pathology. The differential diagnoses include other cervical swellings, such as hemangioma and a thyroglossal duct cyst. Surgical resection is a commonly used treatment method. In recent years, endoscopic positioning and internal fistula burning have had good curative effects for recurrent fourth branchial cleft deformity, with a small chance of recurrence or cancer.

Given its unique position, clinicians should make full use of imaging methods to determine the size, anatomical location and course of the lesion when treating the fourth branchial cleft deformity to ensure the complete and safe surgical resection of the lesion and prevent recurrence.