Voice modifications after voice therapy in a group of 16 subjects with benign vocal fold lesions was assessed using a multidimensional protocol. No clear and significant improvement was observed in aerodynamic and perceptual ratings, while better scores were found on acoustic and self-assessment ratings. Only NHR , Jitt%, VHI e, VHI p and VHI total score showed improvement after rehabilitation treatment. This is the first report in the international literature on vocal modification after voice therapy for benign lesions using a multidimensional protocol. Only a few studies 3
, in fact, have tried to compare the voice characteristics of a group of patients affected by benign monolateral vocal lesions and treated with voice therapy. In a study by Young- Sun et al. 12
, voice evaluation and vocal hygiene were provided to 340 patients with vocal polyps. In order to assess the effect of vocal hygiene eight parameters, (gender, occupational vocal demand, smoking, reflux symptoms, age, hoarseness duration, polyp size and haemorrhagic change) were compared before and after voice therapy. In an article by Cohen et al. 3
, the main outcome measure was voice improvement, defined by the patient, at last follow-up, stating that his/her voice improved sufficiently to meet his/her daily voice needs most of the time. Both studies reported an improvement in the patient's perception of her/his voice quality. However, the voice modifications induced by rehabilitation techniques were not specifically investigated and precise multidimensional data were lacking in both studies. Moreover, neither study used a set of validated questionnaires for the assessment of vocal improvement. Even if the patient's perception of dysphonia, rather than clinical and instrumental measures, is nowadays considered to be the strongest primary outcome measure 23
, voice has to be considered as a multidimensional phenomenon 24
and definition of voice improvement based only on patient report is limited.
Regarding the usefulness of voice therapy, the results reported here are less clear if compared with previous studies; however, if self-assessment data are considered, in our study patients also reported an improvement of voice quality as demonstrated by the statistically significant differences between the VHI p, VHI e and VHI total score before and after the voice therapy. This finding is not surprising since the use of voice in a more efficient manner and the reduction of trauma at the mid-membranous vocal fold, obtained with voice therapy, may improve the patient's self impression of voice, despite the persistence of the polyp or cyst.
In the present study, only the self-assessment measures showed a significant improvement, while objective voice quality was not modified. Various factors may have contributed to this result such as poor adherence to therapy or inadequate choice of rehabilitative technique 25
. However, it is also possible that for benign vocal fold lesions, only a small improvement of voice quality can be achieved with voice therapy. Nonetheless, rehabilitation treatment seems useful for patients as demonstrated by the improvement in self-assessment measures. Thus, we might speculate that voice therapy leads to an improvement sufficient to cope with everyday vocal load. Moreover, even if surgical management of patients in the present study was not analyzed, it is possible to speculate that voice therapy may increase adherence to behavioural and rehabilitative recommendations in the post-operative period.
The present study should be considered as a preliminary report on the effect of voice therapy in the management of benign vocal fold lesions evaluated with a multidimentional protocol. This is, in fact, a consecutive caseseries study, and a control group, receiving for example only vocal hygiene programmes, was not included. For this reason, the evidence level for this study is quite low (Level C according to the UK National Health Service) and it is not possible to demonstrate that the improvement in self-assessment measures is a consequence of rehabilitation treatment. Nonetheless, this is one of the first analyses of the effects of vocal therapy in the management of benign vocal fold lesions. Further studies are needed to better clarify the role of voice therapy in the management of these diseases. Moreover, it is possible that if voice therapy is provided as initial treatment, it may lead to an improvement in the perceived voice quality in some patients with benign vocal fold lesions, and this could make surgical intervention unnecessary. Voice surgeons should consider this possibility during pre-operative counselling.