Late radiation effects on hearing, vestibular function, and taste in brain tumor patients.
OBJECTIVE
To investigate late radiation effects on hearing, vestibular function, and taste after conventional radiotherapy in brain tumor patients.


METHODS
Hearing, vestibular function, and taste were assessed in 33 brain tumor patients irradiated unilaterally to the tumor-bearing hemisphere and the temporal bone. Median observation time after completion of radiotherapy was 13 years; the fraction dose was 1.8 Gy, and mean radiation dose was 53.1 Gy.


RESULTS
Deep ulceration in the external ear canal and osteoradionecrosis on the irradiated side was seen in three patients. Reduced hearing was found for air and bone conduction of the irradiated side compared to the opposite side (0.25-2 kHz: 6.1 dB, 4 kHz: 10.3 dB, 6 kHz: 15.6 dB, and 8 kHz: 16.5 dB). For bone conduction, the corresponding figures were 0.25-2 kHz: 5.5 dB and 4 kHz: 8.2 dB. Three patients had a canal paresis of the irradiated side, and three patients had affection of the chorda tympani.


CONCLUSIONS
Irradiation of the temporal bone with doses usually given in the treatment of patients with brain tumors may cause osteoradionecrosis, sensorineural hearing loss, dysfunction of the vestibular inner ear, and loss of taste. Head-and-neck examination should be included in the follow-up of long-term survivors.
Johannesen
Tom B
TB
Department of Medical Oncology and Radiotherapy, The Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway. tomj@trollnet.no
Rasmussen
Kjell
K
Winther
Finn Ø
FØ
Halvorsen
Ulf
U
Lote
Knut
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000532:radiotherapy*; D004424:Ear Canal / Q000528:radiation effects; D005260:Female; D005500:Follow-Up Studies; D006309:Hearing / Q000528:radiation effects*; D006319:Hearing Loss, Sensorineural / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010025:Osteoradionecrosis / Q000209:etiology*; D013649:Taste / Q000528:radiation effects*; D013701:Temporal Bone / Q000528:radiation effects*; D014722:Vestibule, Labyrinth / Q000528:radiation effects*