Usefulness of computed tomography in the etiologic evaluation of adult unilateral vocal fold paralysis

摘要

Background: Unilateral vocal fold paralysis (UVFP) may present as an uncommon complication of extralaryngeal neoplasms, requiring diagnostic scrutiny to seek occult tumors or diseases. The aim of this study was to examine the utility of computed tomography (CT) in evaluating adult UVFP of unknown etiology. Methods: From January 2010 to December 2011, UVFP was diagnosed in 822 patients at our tertiary-care center. In 634 patients, a readily identifiable cause of the UVFP was evident and therefore there was no need for any imaging; in the remaining 188 patients, the etiology could not be determined. Among this latter group, 153 patients underwent chest radiography (CXR) and contrast-enhanced CT imaging from the skull base to the midchest. Results: In 36 of the 153 (23.5 %) patients, CT revealed the cause of the UVFP: lung cancer in 12 patients, thyroid carcinoma in 7 patients, skull-base tumor in 4 patients, aortic aneurysm in 4 patients, esophageal cancer in 3 patients, thymus tumor in 2 patients, pericardial effusion in 1 patient, and other neck lesions in 3 patients. CXR and neck ultrasonography also identified the etiology in 14 and 12 patients, respectively. During follow-up after the initial CT, none of the patients with idiopathic UVFP was determined to have an underlying disease that would have explained the paralysis. Conclusion: CT is a useful single-imaging method for evaluating the etiology of adult UVFP. This approach may reveal occult tumors or previously undiagnosed diseases as the cause of the paralysis, thus improving patient care.