Thesis
English
ID: <
10670/1.uls4pm>
Abstract
objective: Analyse the natural evolution of tumour size and hearing in 151 patients with vestibular schwannome (VS) monitored and evaluate the same parameters for a part of the group treated with LINAC stereotaxic radiosurgery (SRS). Methods: Prospective study of patients tested with MRI and audio vestibular tests for inclusion, during the monitoring period and after SRS. The hearing was graduated according to the Gardner-Robertson (GR) scale and the tumour size according to the Koos scale. Statistical analysis includes survival analysis of Kaplan-Meier, multivariate analysis with linear regression and logistics. Patients with a useful hearing were specifically analysed. Results: During the monitoring period (average 24 months, deviation 6-96), the annual risk of degradation of the GR class was 6 % for GRI patients and 15 % for IBCs. Hearing loss as an initial symptoms was a significant predictive factor for subsequent hearing aggravation (p = 0.003). Tumour growth was 25 % at the last observation during monitoring. For patients treated with LINAC, the preservation of a useful hearing was 51 % to 1 year and 36 % to 3 years. Tumour control was 94 % and 91 % respectively. Conclusion: In patients with VS, hearing loss already present in diagnosis is a negative predictive factor for the evolution of hearing. LINAC stereotaxic radiosurgery is effective for tumour control. Patients who have maintained their pre-treatment status have an annual rate of reduced hearing loss after SRS compares with it before treatment. This suggests a potential protective effect of the SRS, provided that the cochlear function is preserved.