Lingual thyroglossal duct cyst with recurrence after cystectomy or marsupialization under endoscopy: diagnosis and modified Sistrunk surgery.

OBJECTIVE: To explore the radiologic characteristics of lingual thyroglossal duct cyst relevant to diagnosis. In addition, to probe the feasibility of modified Sistrunk surgery for patients who experience recurrence after cystectomy or marsupialization under endoscopy.

STUDY DESIGN: Retrospective.

METHODS: Seven patients, three male and four female, who had been diagnosed with lingual thyroglossal duct cysts, had received cystectomy or marsupialization under endoscopy between one and eight times with cyst recurrence soon after every operation. All of these cases were evaluated by CT before proceeding with the latest modified Sistrunk surgery. During surgery, we routinely used methylene blue to trace the cysts, and then we used an enlarged Sistrunk procedure for such cases.

RESULTS: The CT images demonstrated that there were cysts located posteriorly to the tongue that had a close relationship with the hyoid bone and the foramen cecum. In addition, the results of the pathological examinations were consistent with thyroglossal duct cysts. During the postoperative follow up of 18 to 31 months, the patients did not show any symptoms or signs of recurrence. The results of their most recent examinations, two by laryngoscopy and five by CT scan, did not reveal any abnormality in their pars laryngea pharyngis.

CONCLUSIONS: CT could differentiate lingual thyroglossal duct cysts from the other cysts occurring at the lingual root. For those patients with lingual thyroglossal duct cysts that recur after cystectomy or marsupialization under endoscopy, the modified Sistrunk operation could be a suitable treatment option.