Management of a Piriform Sinus Fistula With Chronic Neck Infection in an Adult.

Objectives: A pyriform sinus fistula (PSF) is a rare congenital anomaly due to failed obliteration of the third or fourth pharyngeal pouch. Diagnosis and management of PSF remains controversial. We present a case of PSF and discuss its diagnosis and management.

Methods: Case report and literature review.

Results: A 26-year-old female with a chronic left lateral neck abscess was diagnosed with a left PSF. She underwent surgery through a combined approach to close the openings of the PSF, internally and externally. We first placed a blunted ET tube into the internal opening of the PSF. We then performed an external transcervical approach to close the PSF at the cricothyroid membrane. Briefly, after a neck debridement and washout of the chronic neck infection, we identified the recurrent laryngeal nerve (RLN) in Lore's triangle. We performed left hemithyroidectomy to facilitate the dissection and protection of the RLN to its entrance into the larynx. A flexible laryngoscope was then inserted into the left piriform sinus through the ET tube to guide external dissection by transillumination. The scar tissue attached to the superior pole of the left thyroid lobe was then ligated and divided along the cricothyroid membrane. Lastly, we cauterized the internal opening of the PSF. The patient has remained recurrence-free for 1.5 years with normal vocal cord mobility. Histopathology revealed presence of a squamous-lined tract adjacent to the thyroid tissue.

Conclusions: Surgical treatment for patients with PSF should be aimed at closing the internal and external openings of the PSF, debriding chronic neck infection, and protecting the laryngeal nerves, instead of removing the entire tract. A concurrent hemithyroidectomy facilitates the identification and protection of the RLN, as well as excision of the tract. Differentiation between third and fourth branchial cleft fistulae may not be clinically necessary, as it is unlikely to alter the therapeutic plan.