Śródoperacyjne monitorowanie słuchu w czasie operacji usuwania guza okolicy kÄ ta mostowo-móżdżkowego

Cerebello-pontine angle tumors (CPAT) are diagnosed in stage with relatively good preserved hearing. Additional challenge for neurotologists, in cases with good hearing, is to preserve intraoperatively hearing on socially useful level. To improve hearing results in CPAT patients intraoperative monitoring of hearing showed its utility. Intraoperative monitoring let avoid many critical moments concerning hearing and modify tumor removal technique in these options of monitoring in which hearing is monitored in real-time domain. The authors presented and analyzed many audiological techniques of intraoperative monitoring specifically focusing on those showing utility in operation room conditions. Elektrophysiological techniques and otoacoustic emissions were discussed as tools for intraoperative monitoring of hearing. Advantages and disadvantages of both strategies are discussed. The authors emphasize that combination of brainstem evoked auditory responses (ABR) with distortion product otoacoustic emissions (DPOAE) or with transtymapanal elelctrocochleography (TT-EcochG) is the best option of intraoperative monitoring of hearing. Such a combination makes possible to monitor hearing function in real time domain - every 3 to 6 sec (DPOAE and TT-EcochG) - with ABR reflecting complex hearing pathway activity recorded every 20-30 sec. Another value of intraoperative monitoring in patient with preserved hearing is an educational aspect for surgeon. Intraoperative monitoring in real time domain enables to identify perfectly all dangerous moments and surgical maneuvers responsible for reversible and irreversible hearing damage.