Taipei City Government

A healthy 31-year-old male complained of sudden hearing difficulty in the left ear and had a sense of imbalance. At the outpatient clinic, a physical examination found no abnormality, and there was only single-frequency hearing loss in the left ear during the hearing test. As Auditory Brainstem Response (ABR) showed abnormal auditory nerve response in the left ear, a head magnetic resonance imaging (MRI) was also performed; unexpectedly an acoustic neuroma on the left side was found.
According to Dr. Li Guo-Xi, Director of the Department of Otolaryngology at the Ren’ai Branch of Taipei City Hospital, acoustic neuroma is a benign tumor arising from the Schwann cells of the eighth cranial nerve, also known as the vestibulocochlear (auditory) nerve. It accounts for about 8% of intracranial tumors, with an incidence rate of about one out of 100,000 people. However, it mainly occurs in people between the ages of 30 and 60, and is mostly unilateral.
Otolaryngologist Xu Yu-Lin said there is a high detection rate of acoustic neuroma using diagnostic audiology inspection. Symptoms such as asymmetrical hearing loss will pose a red flag for acoustic neuroma. At present, the standard for diagnosis is through head MRI, where tumors above 0.4 cm can be detected.
The treatment methods include tracking, surgery and radiotherapy. Small tumors can be treated by tracking, or be removed by middle cranial fossa surgery or suboccipital retrosigmoid approach, and there is a higher chance of retaining hearing. Big tumors could be removed via labyrinthine or other surgical methods. However, surgeries often cause obvious damage to hearing. Hearing after surgery could be retained only under certain special circumstances. Most surgeries could retain facial nerve functions.
Dr. Li Guo-Xi said that the human ear is an auditory organ as well as a balance organ. Hence, when there are ear diseases, the common symptoms include abnormal hearing, tinnitus, dizziness, ear fullness, ear swelling, etc. If the symptoms persist, you should consult an otolaryngologist. Early diagnosis and early treatment normally produce good results.