INTRODUCTIONRadiation injury resulting in sudden, late onset sensorineural hearing loss is a recognised complication in patients who have received head and neck irradiation. We describe the magnetic resonance imaging (MRI) of the internal acoustic canal (IAC) of 3 such patients and postulate a cause for these findings.

CLINICAL PICTUREA total of 63 patients were referred for MRI IAC for sudden-onset sensorineural hearing loss. Of these patients, only 5 patients had abnormal MRI finding in the affected ear and the remaining patients had normal studies. Two patients had acoustic neuromas. Three patients demonstrated high T1-weighted signal in the labyrinths of the affected ears and had past histories of head and neck irradiation. The MRI findings and medical records of these 3 patients were reviewed and described in this case series.

OUTCOMEHigh labyrinthine signal on unenhanced T1-weighted images in the symptomatic ear of these patients was observed, suggesting the possibility of haemorrhage. In the patient who had a history of brain tumour, susceptibility artifacts were also seen in the right hemipons on the gradient-echo images, indicating the presence of paramagnetic substances from previous therapy.

CONCLUSIONWe postulate that labyrinthine haemorrhage is a rare, late complication of head and neck irradiation, resulting in sudden sensorineural hearing loss.

Female ; Head and Neck Neoplasms ; radiotherapy ; Hearing Loss, Sensorineural ; etiology ; Hearing Loss, Sudden ; etiology ; Hemorrhage ; complications ; Humans ; Labyrinth Diseases ; complications ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Radiotherapy ; adverse effects ; Radiotherapy Dosage ; Time Factors

Heart Failure ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Pleural Effusion ; diagnostic imaging ; Tomography, X-Ray Computed ; Ventricular Dysfunction, Left ; diagnostic imaging