To determine the prognostic value of laryngoscopy in predicting the recovery of unilateral vocal fold paralysis.

A prospective study was carried out of all patients with unilateral vocal fold paralysis without a progressive lesion or arytenoid dislocation.

Among the 66 candidates, 15 recovered. Patients with interarytenoid paralysis (p < 0.001) or posterolateral tilt of the arytenoid (p = 0.028) had less chance of recovery. Among 51 patients who did not recover, 25.49 per cent regained phonatory function by compensatory movement of the normal side; the rest required an intervention. Intervention requirement was significantly less for those patients who had isolated glottic level compensation. The paralysed vocal fold was at the same level in 32.35 per cent of patients, higher in 38.23 per cent and lower in 29.42 per cent. In those in whom vocal folds were in the abducted position (46.67 per cent), the affected vocal fold was at a lower position on phonation. Inter-observer reliability assessment revealed excellent to good agreement for all criteria.

Interarytenoid paralysis and posterolateral tilt of the arytenoid were predictors of poor recovery.