Inspections of causes in vocal cord paralysis with diagnostic imaging

The vocal cord paralysis may be caused by the occult type malignancies. The tumor occupies along the route of the vagus nerve or recurrent laryngeal nerve. To detect such a malignant tumor, it is advocated that the diagnosis should be performed with various kind of figures, such as X-ray picture, CT and ultrasonography. Consequently 13 cases were diagnosed to the malignant tumors among 31 vocal cord paralysis cases. They were thyroid cancer, lung cancer, esophageal cancer and others. CT and ultrasonography were very useful for the evaluation of the mass lesions in the head and neck area. Additionally, the fine needle aspiration biopsy under the ultrasonographic imaging was available to diagnose whether the mass lesions were benign or malignant. (author)