Background: To develop an updated screening, treatment and follow-up strategy for acquired unilateral vocal fold paralysis (UVFP), this Taiwan study investigated concurrent etiologies in patients treated in a tertiary medical center. Methods: This retrospective study was conducted at the voice centers of Chang Gung Memorial Hospital, Keelung, and Chang Gung Memorial Hospital, Linkuo Medical Center, Taiwan. Outpatient and inpatient medical records of patients with UVFP treated between January, 2002 and March, 2006 were retrospectively reviewed. Patients with laryngeal/hypopharyngeal malignancies, those with incomplete examination and follow-up data and those with congenital UVFP were excluded from the study.

Results: One hundred sixty-one patients, including 104 females and 57 males, with ages ranging from 15 to 85 years, met the inclusion criteria. One hundred ten patients (68%) had left side UVFP. The causes were iatrogenic in 48%, subclinical tumor in 12%, neck trauma in 7%, radiation effect in 6% and other causes in 5%. Thyroidectomy was the most common surgical cause of UVFP (n= 51). The most common origins of subclinical tumors were the thyroid (n= 8) and lung (n= 6). In patients younger than 30 years, neck trauma was a major cause of UVFP.

Conclusions: A tailored management strategy for UVFP is needed because vocal fold immobilization is an important sign of various underlying diseases. Extended follow-up is crucial in idiopathic UVFP due to the risk of undiagnosed subclinical tumor.