Can maximum phonation time predict voice outcome after thyroplasty type I?

BACKGROUND: Thyroplasty type I, as introduced by Isshiki and colleagues almost 30 years ago, has become the gold standard of improving glottal incompetence caused by unilateral vocal fold paralysis. Intraoperative assessment of the adequacy of glottal closure is subjective and based on the perceptual judgment of vocal quality and degree of improvement in glottal gap size. OBJECTIVE/HYPOTHESES: The primary purpose of this study was to investigate whether the intraoperative measurement of maximum phonation time (MPT) is an adequate predictor of voice outcome after thyroplasty type I. To assess this possibility, it was necessary to evaluate the effect of body posture (seated vs. supine) and anesthesia (none vs. light sedation) on the measure of MPT. STUDY DESIGN: A prospective study of 20 individuals with unilateral vocal fold paralysis was undertaken. METHODS: Subjects were assessed at three time points: pre-, intra-, and postoperatively across parameters of breathiness rating, glottal gap size, glottal flow rate, and MPT. RESULTS: Results indicated that MPT was significantly lower in the supine versus seated position. In addition, light sedation resulted in a trend toward lower MPT that was not statistically significant. Finally, the intraoperative measurement of MPT, although lower than a 1-month postoperative measurement, was significantly predictive of the outcome. CONCLUSIONS: The intraoperative measure of MPT appears to be an adequate predictor of the postoperative outcome.

Spastic/spasmodic vs. tremulous vocal quality: motor speech profile analysis.

Strained, strangled, and tremulous vocal qualities that are typically seen in adductor spasmodic dysphonia (ADSD), voice tremor (Tremor), and the spastic dysarthria of amyotrophic lateral sclerosis (ALS) may sound similar and be difficult to differentiate. The purpose of this study was to determine if these vocal qualities of neurologic origin could be differentiated on the basis of acoustic and motor speech parameters. Three groups of subjects (ADSD, ALS, and Tremor) were analyzed by the Motor Speech Profile System (Kay Elemetrics, Lincoln Park, NJ) for fundamental frequency (Fo), standard deviation of Fo, diadochokinetic rate (ddk), standard deviation of ddk, mean intensity and standard deviation of ddk, frequency and amplitude variability in connected speech, and speaking rate in connected speech. Profiles of the three groups are presented with the significant features that differentiated one from the other.

Early results of transcutaneous injection laryngoplasty with micronized acellular dermis versus type-I thyroplasty for glottic incompetence dysphonia due to unilateral vocal fold paralysis.

Medialization thyroplasty (type I) has become the gold standard to improve glottic closure due to unilateral vocal fold paralysis. A newer injection method utilizing homologous collagen from cadaveric human tissue has been described as an attractive alternative as no donor site is required, there is a very low risk of hypersensitivity, and the intact, acellular collagen fibers may suffer a reduced long-term reabsorption rate. Preliminary results on eight patients comparing presurgical and postsurgical parameters (perceptual, stroboscopic, acoustic, and aerodynamic) revealed comparable results when compared with a control group of individuals, age- and sex-matched, that had undergone standard medialization thyroplasty (type I). Further study is needed to assess the long-term results with this minimally invasive method of vocal fold medialization.