Incidence of long-term ipsilateral and contralateral ototoxicity following radiotherapy for nasopharyngeal carcinoma

Long-term ototoxicity following radiotherapy for NPC can occur in either the ipsilateral or contralateral ears. Pathophysiology varies between and within each side. The post-therapy increase in OME on the contralateral side was thought to be due to radiotherapy-induced Eustachian tube damage, and the sensorineural threshold deterioration in at least 4 ears was thought to be due to chronic cochlea damage secondary to COM.