ACOUSTIC VOICE ANALYSES FOR THE DOCUMENTA TION OF VOICE REHABILITATION AFTER LASER-SURGICAL RESECTION OF LARYNGEAL CARCINOMAS

Following curative minimal-invasive laser resection of T1-T3 laryngeal carcinomas, patients were subjected to an intensive voice rehabilitat ion. Therapy was effected twice a day for approximately 2 months, util izing the concept of functional voice therapy. Before and after rehabi litation, acoustic analyses were made by using two different computer- supported measuring systems: (1) the ''multidimensional voice program' ' (Kay Elementrics Corp.) and (2) a novel software program developed i n Gottingen that includes a new voice quality parameter based on corre lations between frequency bands. Acoustic analyses showed superiority of the glottal versus supraglottal compensatory phonation. Findings sh owed that not all acoustic parameters equally documented voice improve ment after rehabilitation. The standard deviation of fundamental frequ ency was the only parameter showing a significant post-therapeutic imp rovement. A further suitable acoustic method proved to be the voice qu ality parameter that has been newly introduced by us. In contrast to a nalogous parameters of other methods, this approach is independent of the exact periodicity of the glottal excitation function, thus permitt ing reliable results to be obtained even with aphonic or heavily dysph onic voices.