Voice Onset Time in Patients Using Speech Prosthesis After Total Laryngectomy

Our study was carried out to investigate the presence of known differences in voice and articulation quality after total laryngectomy. Patients provided phonation with tracheoesophageal speech prosthesis. We recorded patients' voice onset time (VOT) values - an important parameter of acoustic analysis.

The study included 18 patients with total laryngectomy who received valvular speech prosthesis via a primary or secondary tracheoesophageal fistula between 2009 and 2011 at the Istanbul Training and Research Hospital Otorhinolaryngology Clinic. Twenty healthy male volunteers were included as the control group. All subjects produced the /pa/, /ta/, /ka/ syllables three times, and the VOT values were determined by recording the voices on a computer.

A total of 38 male patients, 18 of which were patients with total laryngectomy and tracheoesophageal speech prosthesis (aged between 46 and 75 years, mean: 59) and 20 controls (aged between 50 and 70 years, mean: 58), were included in the study. The age distribution of the groups did not differ statistically (P > 0.05). In the total laryngectomy and tracheoesophageal speech prosthesis group, the VOT mean values of the /ka/ syllable were significantly lower than the control group, whereas the /pa/ (P = 0.848) and /ta/ VOT mean values (P = 0.809) were similar between groups.

This study shows that there is no significant difference in the articulation of voiceless plosives, except for the /ka/ sound, between patients using speech prostheses after total laryngectomy and controls. For standardization of these measured values and their use in clinical practice, it may be beneficial to support this study with studies that involve more patients and examine different indicators showing the quality and intelligibility of other voice characteristics.