Mutational falsetto: intervention outcomes in 45 patients.

OBJECTIVE: The aim of this study was to evaluate the outcomes of therapeutic intervention in patients with mutational falsetto, by applying perceptual and acoustic analysis before and after voice therapy. MATERIALS AND METHODS: Forty-five consecutive patients with mutational falsetto were studied retrospectively. Acoustic analysis (i.e. fundamental frequency, jitter, shimmer, and formants one, two and three) was performed using the Multi-Dimensional Voice Program. Perceptual voice analyses were performed, including graded severity-roughness-breathiness-aesthenicity-strain assessment. RESULTS: Subjects' fundamental frequency, voice formants one, two and three, jitter, and shimmer were greater before than after treatment. There were statistically significant differences between pre- and post-treatment average values for fundamental frequency, jitter and shimmer. There were also statistically significant differences between pre- and post-treatment average values for formants one and two. These results were maintained after six months of follow up, and there was no significant difference between results at three- and six-month follow up. According to perceptual evaluation, each subject's voice had altered from mutational falsetto to chest voice by completion of the intervention. Thus, all of the patients successfully lowered their modal speaking voice to an appropriate level. CONCLUSION: In the light of objective evaluations, and by applying the study treatment protocol, these results suggest that normal voice can be maintained after intervention, at six months' follow up.

Aerodynamic and acoustical measures of speech, operatic, and Broadway vocal styles in a professional female singer.

Understanding how the voice is used in different styles of singing is commonly based on intuitive descriptions offered by performers who are proficient in only one style. Such descriptions are debatable, lack reproducibility, and lack scientifically derived explanations of the characteristics. We undertook acoustic and aerodynamic analyses of a female subject with professional experience in both operatic and Broadway styles of singing, who sang examples in these two styles. How representative the examples are of the respective styles was investigated by means of a listening test. Further, as a reference point, we compared the styles with her speech. Variation in styles associated with pitch and vocal loudness was investigated for various parameters: subglottal pressure, closed quotient, glottal leakage, H1-H2 difference (the level difference between the two lowest partials of the source spectrum), and glottal compliance (the ratio between the air volume displaced in a glottal pulse and the subglottal pressure). Formant frequencies, long-term-average spectrum, and vibrato characteristics were also studied. Characteristics of operatic style emerge as distinctly different from Broadway style, the latter being more similar to speaking.

Comparison of neuromuscular blockade and recovery with botulinum toxins A and F.

Intramuscular injection of botulinum toxin A is used to treat focal dystonias. Because immunoresistance has been documented in some patients, other molecular forms of the toxin have been evaluated clinically. The present investigation compared the time course and extent of neuromuscular blockade and recovery of botulinum toxin types A and F using an electromyographic monitoring system implanted in the rat hindlimb. For a given dose, the degree and duration of blockade was more complete with type A toxin. Delayed onset of recovery in animals that received high doses of type A toxin allowed time for denervative changes to prevent a full return to baseline, as confirmed histologically. Conversely, animals receiving type F toxin fully recovered within 30 days at all dose levels. The rapid recovery with type F toxin suggested that neuromuscular transmission was restored via the original terminals rather than through functional collateral sprouting. The reversible nature of blockade with this molecular species puts in question its future clinical utility.

Long-term-average spectrum characteristics of country singers during speaking and singing.

Five premier male country singers involved in our previous studies spoke and sang the words of both the national anthem and a country song of their choice. Long-term-average spectra were made of the spoken and sung material of each singer. The spectral characteristics of county singers' speech and singing were similar. A prominent peak in the upper part of the spectrum, previously described as the "speaker's formant," was found in the county singers' speech and singing. The singer's formant, a strong spectral peak near 2.8 kHz, an important part of the spectrum of classically trained singers, was not found in the spectra of the country singers. The results support the conclusion that the resonance characteristics in speech and singing are similar in country singing and that county singing is not characterized by a singer's formant.

Outcomes assessment following treatment of spasmodic dysphonia with botulinum toxin.

Spasmodic dysphonia (SD), a disabling focal dystonia involving the laryngeal musculature, is most commonly treated by the intramuscular injection of botulinum toxin (BTX). Although the treatment is well tolerated and generally produces clinical voice improvement, it has never been statistically shown to alter the patient's perception of voice quality or general health. Declining resources for medical care mandate that treatment outcomes be documented. A prospective analysis of the effects of BTX on the patient's perception of voice and general health was undertaken. The Voice Handicap Index (VHI) and Short Form 36 (SF-36) surveys were administered to patients before treatment and 1 month after. Pretreatment and posttreatment scores were analyzed with a Student's t-test. On the VHI, improvements in the patients' perception of their functional, physical, and emotional voice handicap reached statistical significance (p < or = .0005). On the SF-36, patients had statistically significant improvements in mental health (p < or = .03) and social functioning (p < or = .04). Treatment of SD with BTX significantly lessened the patients' perception of dysphonia. In addition, it improved their social functioning and their perception of their mental health. These outcome measures justify the continued treatment of SD with BTX.

Formant frequencies in country singers' speech and singing.

In previous investigations breathing kinematics, subglottal pressures, and voice source characteristics of a group of premier country singers have been analyzed. The present study complements the description of these singers' voice properties by examining the formant frequencies in five of these country singers' spoken and sung versions of the national anthem and of a song of their own choosing. The formant frequencies were measured for identical phonemes under both conditions. Comparisons revealed that the singers used the same or slightly higher formant frequencies when they were singing than when they were speaking. The differences may be related to the higher fundamental frequency in singing. These findings are in good agreement with previous observations regarding breathing, subglottal pressures, and voice source, but are in marked contrast to what has been found for classically trained singers.

Voice source characteristics in six premier country singers.

Voice source characteristics as derived from inverse filtering were analyzed in 6 country singers' speech and singing. Results showed that the closed quotient varied systematically with vocal loudness, and that glottal compliance (the ratio between transglottal AC volume displacement and subglottal pressure) decreased with increases in fundamental frequency but remained unaffected by vocal loudness. No striking differences were found in source characteristics between speech and singing within subjects. The degree of phonatory press, as judged by a panel of 19 expert listeners, appeared related to the range in which the singer was singing and to the sound pressure level gain from a doubling of subglottal pressure.

Speech outcomes after laryngeal cancer management.

As our ability to treat laryngeal cancer and prolong the lives of our patients improves, we must place increasing importance on maintaining the best voice possible in every case. Treatment options for laryngeal cancer continue to expand, and it is important that otolaryngologists stay well informed; not only concerning the local control and disease-free survival associated with each new treatment, but also the expected voice result. This article describes the voice and speech outcomes that are associated with various treatments for laryngeal cancer. In addition, comparisons of the expected voice results for different therapeutic modalities are examined.

Estimated subglottal pressure in six professional country singers.

Estimates of subglottal pressure in six professional male country singers were obtained during the /p/ occlusion while the subjects spoke, sang a country tune, and sang the tune of the United States national anthem. The subglottal pressure values, which were very similar in both the speech-like and singing-mode syllables, usually measured below 45 cm of water column, but they ranged as high as 59 cm. The sound pressure level in singing was also measured and was lower than that discovered in classically trained singers at high subglottal pressures.

Long-term follow-up of recurrent laryngeal nerve avulsion for the treatment of spastic dysphonia.

Long-term follow-up of 3 to 7 years is reported on 18 patients who had undergone recurrent laryngeal nerve avulsion (RLNA) for the treatment of adductor spastic dysphonia (SD). Data on neural regrowth after previous recurrent laryngeal nerve section (RLNS) are presented in 2 of these 18 patients. We introduced RLNA as a modification of standard RLNS to prevent neural regrowth to the hemiparalyzed larynx and subsequent recurrence of SD. We have treated a total of 22 patients with RLNA, and now report a 3- to 7-year follow-up on 18 of these 22 patients. Resolution of symptoms was determined by routine follow-up assessment, perceptual voice analysis, and patient self-assessment. Sixteen of 18, or 89%, had no recurrence of spasms at 3 years after RLNA as determined at routine follow-up. Two of the 16 later developed spasms after medialization laryngoplasty for treatment of weak voice persistent after the avulsion. This yielded a total of 14 of 18, or 78%, who were unanimously judged by four speech pathologists to have no recurrence of SD at the longer follow-up period of 3 to 7 years. Two of these 4 patients were judged by all four analysts to have frequent, short spasms. The other 2 were judged by two of four analysts to have seldom, short spasms. Three of 18 patients presented with recurrent SD after previous RLNS. At the time of subsequent RLNA, each patient had evidence of neural regrowth at the distal nerve stump as demonstrated by intraoperative electromyography and histologic evaluation of the distal nerve stump. One remained free of SD following RLNA, 1 was free of spasms at 4 years after revision avulsion but developed spasms after medialization laryngoplasty, and the final patient developed spasms 3.75 years after revision RLNA. Medialization laryngoplasty with Silastic silicone rubber was performed in 6 of 18, with correction of postoperative breathiness in all 6, but with recurrence of spasm in 3. Spasms resolved in 1 of these with downsizing of the implant. We conclude that RLNA represents a useful treatment in the management of SD in patients not tolerant of botulinum toxin injections.

Video laryngoscopy.

New techniques for visualing the upper and part of the lower airway provide for efficient assessment of airway dysfunction. Equipment is available for video recording during the assessment, which can be done either in the caregiver's office/clinic or during stress testing in an exercise facility. Case reports that illustrate the diagnostic use of video laryngoscopy as well as adjunct to therapy are presented in this article.

Endoscopic vocal fold microflap: a three-year experience.

Surgical techniques for the removal of vocal fold (VF) disorders that arise within the lamina propria must permit the preservation and/or restoration of VF vibratory characteristics. The endoscopic VF microflap is designed to do such. A retrospective study was undertaken to evaluate the efficacy of this procedure. Forty microflaps (7 bilateral, 1 revision) were performed on 32 patients. Charts and surgical pathology findings were reviewed. Preoperative and 3-month postoperative video recorded voice samples and stroboscopic examination results were compared. Findings on perceptual voice analysis did not significantly change. Stroboscopic examinations revealed improved postoperative VF closure in 27 of 29 patients with impaired preoperative closure and return of mucosal wave in 18 of 24 VFs operated on for the excision of cysts or polyps. When present preoperatively (6 patients), the mucosal wave was preserved. Most patients (28 of 30) rated themselves as clinically improved. The endoscopic VF microflap is efficacious in the treatment of selected VF disorders. The surgical technique is discussed.

Silastic medialization and arytenoid adduction: the Vanderbilt experience. A review of 116 phonosurgical procedures.

From April 1987 to April 1992, 116 phonosurgical procedures were performed to treat glottal incompetence. The initial numbers of these surgical procedures included the following: 29 primary Silastic medializations, 3 primary Silastic medializations with arytenoid adduction, 53 secondary Silastic medializations, 4 secondary Silastic medializations with arytenoid adduction, and 11 bilateral Silastic medializations. These procedures are useful in treating unilateral true vocal cord paralysis, scarring, bowing, or paresis, as well as bilateral true vocal cord bowing. Of the initial 100 patients, 16 later underwent a revision with either a larger implant's being placed or an arytenoid adduction. Primary Silastic medialization is the placement of an implant under general anesthesia in the same surgical setting in which laryngeal innervation is sacrificed. Secondary Silastic medialization is the placement of an implant under local anesthesia for a preexistent vocal cord malfunction. In either case, overall voice results for unilateral paralysis are very good. Primary Silastic medialization significantly decreases the postoperative rehabilitation period in skull base patients because of the immediate postoperative glottal competence and decreased use of perioperative tracheotomy. Bilateral implants yielded good results in 6 patients with presbylaryngis, but 6 other patients with bowing from other causes experienced only moderate improvement in speech quality. There were no implant extrusions; however, 1 implant was removed secondary to a persistent laryngocutaneous fistula in a patient who had previously undergone laryngeal irradiation. This was the only complication in this series.

Recurrent laryngeal nerve avulsion for treatment of spastic dysphonia.

Treatment of spastic dysphonia by recurrent laryngeal nerve section has resulted in reproducibly good results in the early postoperative period in most patients. However, critical long-term follow-up has shown a high recurrence rate of adductor spasms by the third year after initial nerve section. A patient who developed recurring adductor spasms 1 year after nerve section was reexplored, with identification of neural regrowth into the distal segment of the recurrent laryngeal nerve. The technique of neural avulsion removing the distal nerve up to its insertion into the laryngeal muscles is described. Neural regrowth, which is just one of the possible mechanisms for recurrence of spastic dysphonia, should be prevented by this surgical modification. Twelve patients who have undergone neural avulsion primarily for spastic dysphonia are being followed up without recurrence of symptoms thus far. Although these results appear promising, this short follow-up that averages 1.5 years must be extended to firmly support these concepts.

Intra-subject variability in FO-SPLmin voice profiles.

Representations of a subject's minimum vocal intensities (SPLmin) at selected levels of pitch range are called, FO-SPLmin Profiles. Such displays potentially are an indirect means of documenting a person's change in laryngeal function and status. The potentiality is limited by insufficient evidence that subject's performances are replicable on repeated testing. As a pilot study, four normal adults produced their SPLmin at 1/3 octave increments of pitch range on three occasions over a 2-week period. It appears that FO-SPLmin Profiles are replicable. The magnitudes of SPLmin seem to correlate with increments of pitch range at which subjects phonated and increase at a rate of 8 to 12 dB/octave starting around 65 dB (3.8 cm from the lips).