[Speech visualization for evaluation of iatrogenic recurrent laryngeal nerve injuries].

A study was conducted to investigate the intra operative laryngeal recurrent nerve injury and subsequent vocal disturbances. The recovery of voice condition in group of 20 patients with unilateral laryngeal nerve injury was examined by the whole range of both presurgical and postsurgical tests. Patients were selected from a group a 1867 surgical treated in 3-rd Department of Surgery Jagiellonian University School of Medicine in years 1988-1993. We recorded and analysed 1100 words with identical acoustic test. The research was conucted in 3-4 days, 3 moths, 6 months and 1 year after operation in a non-echo chamber with special equipment in the Department of Mechanic and Vibro-Acoustic of the Academy of Mining and Metallurgy in Krakow, Poland. On the basis of obtain results, we found that recovery of voice, in one year after surgery, occurs in 87.5% patients with laryngeal recurrent nerve injury.