Imaging Findings in Neonates With Congenital Pyriform Sinus Fistula: A Retrospective Study of 45 Cases

Background: Congenital pyriform sinus fistula (CPSF) is a rare branchial cleft deformity. The characteristics and management of CPSF in neonates are different from those in children or adults, and a comprehensive understanding of the imaging features of neonatal CPSF can facilitate its preoperative diagnosis. Thus, the aim of this study was to summarize the ultrasonography (US) and CT imaging findings of CPSF in neonates.Methods: Forty-five full-term neonates with CPSF, confirmed by pathology after surgical resection from January 2012 to October 2020, were included in this retrospective study. All patients underwent preoperative cervical US and contrast-enhanced CT examinations, and the imaging findings were analyzed.Results: Forty-six cervical cystic masses were found in 45 neonates, including one case with bilateral lesions, three cases with lesions on the right side, and 41 cases on the left side. Both US and CT detected neck abnormality among all cases, while the diagnostic accuracy of US (15/46, 32.6%) was lower than that of CT (42/46, 91.3%). Moreover, CT showed significantly higher detection rates of intralesional air bubbles, involvement of the ipsilateral thyroid, deviation of the airway, and expansion into the mediastinal and retropharyngeal space compared with the US. As the age increased, it was more likely to present some features including the absence of air-containing, thick cyst wall, and poorly defined border (ρ <0.05).Conclusion: CPSF in the neonates showed distinctive imaging findings on contrast-enhanced CT scan, which provides important supplementary information for the diagnosis of CPSF after the initial US examination.

Outcomes of endoscopic chemo- and laser-cauterizations and open fistulectomy for pyriform sinus fistula

Background Acute suppurative thyroiditis through the congenital pyriform sinus fistula (PSF) often recurs if the fistula is not resected. Although endoscopic chemo-cauterization (ECC) to obliterate the orifice of the fistula is less invasive than open fistulectomy, it may require repeated treatments. We recently adopted an endoscopic diode laser-cauterization (ELC) system with the intention of improving treatment outcomes in PSF. Here, we describe ELC and compare the outcomes of these three modalities. Methods We evaluated 83 patients with PSF who underwent treatment between 2007 and 2018 at Kuma Hospital, a tertiary thyroid treatment hospital. ECC and ELC were implemented in 2007 and 2015, respectively. Patients who were ineligible for the endoscopic procedures underwent open fistulectomy. Barium swallow studies and computed tomography scan under a trumpet maneuver were performed after treatment to evaluate obliteration or removal of the fistula. Results In total, 70 of the 81 (86%) patients who underwent barium swallow studies after the first treatment achieved obliteration or removal of the fistula. The success rates for open fistulectomy, ECC, and ELC were 100% (9/9), 83% (49/59), and 100% (13/13), respectively. ECC and ELC had significantly shorter operative times and lower blood loss than open fistulectomy. Insufficient opening of the mouth was the major reason for converting endoscopic procedures to open fistulectomy. Conclusions ELC may yield superior outcomes and is therefore the optimal treatment modality for PSF. However, it is still associated with certain limitations. Thus, treatment selection remains dependent on the shape and size of the PSF and the mouth opening of the individual patient.

Misdiagnosis of asymptomatic intrathyroidal pyriform sinus fistula: a case report

Pyriform sinus fistula is uncommon and easily misdiagnosed. Most reported cases occur in children and are associated with either acute suppurative thyroiditis or deep neck infection. Asymptomatic pyriform sinus fistula is difficult to diagnose because it can manifest as an incidental thyroid nodule with highly suspicious malignant features on ultrasonography. The patient was a 41-year-old man with asymptomatic thyroid nodules incidentally detected on ultrasonography. Surgery was performed under the suspicion of thyroid cancer. Pathology findings revealed multiple cystic walls lined by ciliated columnar cells with stratified squamous epithelial cysts in a background of inflammatory and lymphoid cells. Barium swallow examination performed 2 weeks later revealed a sinus tract measuring 1.8 cm that arose from the apex of the left pyriform sinus. The diagnosis and management of pyriform sinus anomalies are challenging. The majority of physicians, including some otolaryngologists, lack an understanding of the disease, which should be considered one of the important differential diagnoses of neck masses. Barium swallow examination, ultrasonography, computed tomography, and laryngoscopy are useful to diagnose this condition.