Accuracy of Ultrasonography and Computed Tomography in the Evaluation of Patients Undergoing Sialendoscopy for Sialolithiasis

Objective To determine the accuracy of the 2 most utilized imaging modalities in obstructive sialadenitis secondary to sialolithiasis—computed tomography (CT) and ultrasonography (US)—using sialendoscopic findings as a comparison standard. To review the impact of CT and US on the management of sialolithiasis managed with sialendoscopy alone and through combined approaches. Study Design Retrospective cohort study. Setting Quaternary academic referral center. Subjects and Methods All cases of patients undergoing sialendoscopy by a single surgeon for suspected parotid and submandibular gland pathology between the October 2013 and April 2016 were reviewed. Results Sixty-eight patients were in this cohort, of whom 44 underwent US, CT, and sialendoscopy; 20 underwent CT and sialendoscopy only; and 4 underwent US and sialendoscopy only. The sensitivity and specificity were 65% and 80% for US and 98% and 88% for CT, respectively. These 68 patients had 84 total stones addressed, with 79 being removed and 5 remaining in situ. The methods of stone removal were sialendoscopy alone (34 stones), open transoral approaches (36 stones), and an external approach: transcervical for submandibular and transfacial for parotid (11 stones). Conclusion US had a lower sensitivity (65%) than what has been reported in the literature (70%-94%), and the majority of missed stones were anterior Wharton’s duct stones. These sialoliths were likely missed due to an incomplete examination. US and CT were complementary in this study, and the findings suggest that both modalities can be utilized to optimize the outcome of sialendoscopy and combined approaches.