Background: To evaluate hearing loss severity according to Brock's gradient and to compare it with the audiometric curve during cisplatin treatment in children with retinoblastoma.
Methods: This was an observational retrospective and retrolective study. Twenty children with the diagnosis of retinoblastoma under cisplatin treatment were included. Audiometric testing was performed before treatment, after the second and fourth doses, and after the final dose.
Results: Decreased audition was observed in 100% of the cases. Ototoxicity can be observed with cumulative doses of 240 mg/m(2) and higher. No improvement in audition was observed and the audition loss progressed from high to medium frequencies; 15% of the patients showed a grade II loss of high frequencies at the end of the second dose. This level was observed in 95% of the cases at the end of treatment. Two years after completion of therapy, no patient showed auditory recovery. Area below the curve showed higher sensitivity to identify initial auditory loss.
Conclusions: Evaluation of audition with Brock's gradient can be performed. The area under the curve is a useful method to identify minor changes in serial conventional audiometry.