Voice profile after type I or II laser chordectomies for T1a glottic carcinoma

To theEditor: I read with considerable interest the article by Sjögren et al, who concluded that a typical laser treated (type I or II laser chordectomies) voice for T1a glottic cancer is characterized by mild breathiness in perceptual analysis. I would like to compliment the authors on their work, but I feel that the conclusions drawn were not made using an appropriate analysis process. As shown in Table 7 of the article, the conclusion of Sjögren et al is different from the results of similar studies conducted by 2 groups of Italian doctors, Peretti et al and Ledda et al, who disclosed roughness to be the dominant feature of a type I or II laser chordectomies treated voice. However, the calculation of the mean of GRBAS scale in Sjögren’s article and the other 2 Italian articles were not performed on the same basis. In Sjögren’s article, 12 patients were excluded with no GRBAS pathology in their 34 cohort cases (the denominator). If they included all patients receiving perceptual analysis as in the other 2 articles, they should have used 34 as the denominator to recalculate the mean grade of breathiness. Therefore, the grade of breathiness should be reduced to 0.82, which is closer to the result of Ledda et al. Also, in Table 3 of the article, I noticed there were 2 patients with intermittent roughness and their grade of roughness pathology was not counted. This classification complicates the statistical analysis and I think the mean grade of roughness will most likely be underestimated compared to other parameters (G,B,A,S). Furthermore, the theory that breathiness comes from incomplete glottic closure is also not well supported by their statistically insignificant results (p 1⁄4 .57). In the article by Peretti et al, the authors observed that regeneration of the neocord after chordectomies not extended beyond the superficial portion of the vocal muscle was associated with complete glottic closure in 89% of patients. The aforementioned glottic closure is common after surgery and may explain why breathiness is not a typical feature of patients in Peretti’s study. In addition, Sjögren et al hypothesized that the dominant feature of roughness in 2 Italian studies might be due to cultural differences, because in other studies vocal fry may have been classed as roughness. I am not sure whether vocal fry was classed as roughness in the 2 Italian studies or not. But I noticed that in Sjögren’s article the reduced mucosal wave was found in all stroboscope-assessable patients but 1. In my opinion, the association between reduced mucosal wave and roughness of voice after chordectomy was still unclear, based on the aforementioned imperfect study design of this retrospective article. In conclusion, this paper is an informative article and I agree with some conclusions such as ‘‘multi-dimensional voice assessment protocol is not to be considered the ultimate way to basically assess the voice.’’ However, based on the limitations of a retrospective study, I propose Head & Neck 32: 824–825, 2010 Published online 29 April 2010 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hed.21423