Results of Early Versus Intermediate or Delayed Voice Therapy in Patients With Unilateral Vocal Fold Paralysis: Our Experience in 171 Patients *F. Mattioli, *M. Menichetti, *G. Bergamini, *G. Molteni, *M. P. Alberici, *,†M. P. Luppi, *,†F. Nizzoli, and *L. Presutti, *yModena, Italy Summary: Objectives. Vocal fold paralysis can have an important impact on a patient’s quality of life. The goal of this study was to compare, in terms of vocal improvement and motility recovery, the post-vocal treatment results of our patients with unilateral vocal fold paralysis (UVFP) when treatment was started early (within 4 weeks from injury) versus intermediate (from 4 to 8 weeks) or delayed (at least 8 weeks after injury) treatment. Study Design. An 11-year retrospective study of patients with UVFP who underwent multidimensional diagnostictherapeutic assessment. Methods. In total, 171 patients with UVFP were included in our study, divided into three groups who underwent early (first group), intermediate (second group), or delayed (third group) voice treatment. All patients underwent voice therapy based on forcible exercises supplemented by manipulations and maneuvers. Results. Of the 171 patients with UVFP, 106 (62%) recovered vocal fold motility. Of these 106 patients, 51/78 (65%) were in the first group, 30/49 (61%) in the second group, and 25/44 (56%) in the third group. A significant (P < 0.0001) reduction in fundamental frequency (Fo) was present in the first group with a manifest improvement in the mean values of Jitter (Jitt%; P ¼ 0.001), Shimmer (Shim%; P < 0.0001), and noise-to-harmonic ratio (NHR; P < 0.0001). A significant (P < 0.0001) reduction in Fo was found in the second group with a manifest improvement in Jitt% (P < 0.001), Shim% (P < 0.0001), and NHR (P < 0.0001). For the third group, no values were statistically significant apart from the improvement in NHR (P < 0.001). Conclusions. This study confirms the importance of early rehabilitation underlining the non-functional vocal recovery in patients who started treatment later than 8 weeks after injury. Key Words: Unilateral vocal fold paralysis–Voice therapy.
INTRODUCTION Unilateral vocal fold paralysis (UVFP) can be caused by unilateral damage to the vagus or recurrent laryngeal nerve.1 The etiology of the paralysis is varied and may include infections; iatrogenic trauma; malignancies; and metabolic, toxic, or idiopathic effects.2–5 UVFP is commonly encountered in clinical practice and can cause dysphonia and/or dysphagia and may be associated with aspiration pneumonia when the superior laryngeal nerve is also involved. Frequently, the paralysis resolves without treatment,6–8 and with it, the sequelae. In other cases, the paralysis persists but the voice can improve for compensation of the contralateral vocal fold. This may occur spontaneously but is facilitated by speech therapy. It has the aim of avoiding a pathological compensation between the false cords or aryteno-epiglottic folds, to obtain the most favorable position for the vocal fold paralysis, and to make the contralateral vocal fold crossing the midline more efficient. Laryngeal manipulations play an important role in logopedic rehabilitation. These manipulations also affect crico-arytenoid articulation with Accepted for publication September 25, 2014. Authors have nothing to disclose and no conflicts of interest. From the *ENT Department, University Hospital of Modena, Modena, Italy; and the ySpeech Pathologist, University Hospital of Modena, Modena, Italy. Address correspondence and reprint requests to M. Menichetti, ENT Department, University Hospital of Modena, via del Pozzo 71, Modena, Italy. E-mail: marcellamenichetti@ hotmail.it Journal of Voice, Vol. -, No. -, pp. 1-4 0892-1997/$36.00 Ó 2014 The Voice Foundation http://dx.doi.org/10.1016/j.jvoice.2014.09.027
the aim of promoting medialization of the vocal process; this passive mobilization also hinders the articulatory block, which would prevent the resumption of motility in the case of recurrent laryngeal nerve restoration. The rehabilitation treatment should start as early as possible and preferably within 4 weeks (early voice therapy), but often the patient comes too late for specialist observation so consequently the start of treatment is delayed (delayed voice therapy). In other cases, the patient accommodates the paralysis, with the paralyzed vocal fold moving to the midline or the contralateral vocal fold crossing the midline and, with this improved closure, the voice improves. In some cases, the paralysis does not improve, there is no accommodation of the paralysis, and the symptoms persist. These patients often receive voice and swallowing therapy and many undergo surgery to improve closure.6 Voice therapy is the treatment of choice in patients with UVFP9 and it can be started immediately, in the first 4 weeks after the appearance of paralysis (early voice therapy), within 4–8 weeks (intermediate voice therapy), or after 8 weeks (delayed voice therapy).10 In the case of unsatisfactory results for the persistence of UVFP with the presence of a glottic gap, in the early stages of paralysis, we usually resort to phonosurgery based on injection procedures with absorbable materials, considering the potential reversibility of the paralysis, and using non-adsorbable materials in the case of more than 12 months of paralysis. The use of early injection laryngoplasty has many supporters in recent literature.11–13 As may be expected, early voice therapy plays an important role in the therapeutic procedure. In the case
2 of an unsatisfactory functional result, laryngoplasty with a resorbable material is used 2 or 3 months after the onset of paralysis. From this perspective, patients with UVFP are prioritized in our phoniatric and logopedic service. The aim of this study was to compare, in terms of vocal improvement and motility recovery, the post-vocal treatment results of our patients with UVFP who started early treatment versus intermediate or delayed treatment. All patients underwent forcible exercises supplemented by manipulations and maneuvers. Our aim was to emphasize the importance of early rehabilitation as demonstrated in our previous work.2 MATERIALS AND METHODS We performed a prospective study of all patients with UVFP between October 2004 and October 2013. A total of 171 patients were treated in our outpatient clinics for Voice Analysis and Rehabilitation and all were included in our study. We excluded from the data analysis 40 patients who had not completed our multidimensional diagnostic-therapeutic assessment. Of the 171 patients, 78 (56 women; 22 men) underwent early voice treatment, 49 (37 women; 12 men) received intermediate voice treatment, and 44 (23 women; 21 men) underwent delayed voice treatment. In the first group, median age was 57 years (range, 19–87 years), in the second, mean age was 55 years (range, 18–82 years), whereas in the third group, median age was 55.5 years (range, 17–82 years). Speech-language pathologists and an otolaryngologist evaluated all patients. The etiology of the paralysis was extensive and varied and this is reported in Table 1. A voice evaluation was performed with a complete head and neck examination and a detailed video-strobolaryngoscopic evaluation of glottal configuration during phonation. Rigid (Storz 90 rigid telescope) and flexible (Pentax FNL 10RP3 fiberscope) endoscopes were used. Videostrobolaryngoscopic evaluation was essential to document the vocal fold position, motility, and morphology, and observe its prolonged vibratory characteristics. The examiner asked the patient to produce an /a/ sound for as long as possible; the voice signal was recorded and stored digitally. Computerized Speech Lab (CSL) version 5.05 software with the 4300B external module (Kay Elemetrics Corporation, Lincoln Park, NJ) was used. It was also important to determine the maximum phonation time (MPT), the longest sustained /a/ sound. Spectrography was performed on the 3-second sustained vowel /a/ sound and the Italian word /aiuole/ (flowerbeds in English). Yanagihara’s classification was used to rate the voice spectrograms adapted to the single vowel /a/. Jitter (Jitt%), Shimmer (Shim%), noise-to-harmonic ratio (NHR), and fundamental frequency (Fo) were calculated. Voice therapy Each patient involved in this study underwent several voice therapy sessions twice a week with an experienced speech/
Journal of Voice, Vol. -, No. -, 2014
TABLE 1. Etiology of UVFP for Patients in This Study
Etiology Thyroid alcoholization Thoracic aorta aneurysm Spastic ataxia Lung carcinoma Carotid endarterectomy Mediastinal surgery Tracheal surgery Vagal neuroma Neurosurgery Inflammation Idiopathic Viral infection Post-intubation Partial thyroidectomy Total thyroidectomy Traumatic
Treated Treated Treated After From Within 4 wk 4 to 8 wk 8 wk Total 1
0
0
1
1
0
1
2
1 2 7
0 0 1
0 1 2
1 3 10
2 1 1 3 0 13 0 5 22 16 3
3 1 0 0 1 11 1 5 12 12 2
1 1 1 0 0 9 0 2 10 16 0
6 3 2 3 1 33 1 12 44 44 5
language pathologist, and the exercises were repeated daily at home during the treatment period. We usually suggest 12/18 sessions, followed by laryngoscopy, or earlier if the speech pathologist suspects restoration of motility should the voice suddenly improve. At the end of treatment, we decide the next strategy. This may include: (i) discontinuation of treatment if the larynx is mobile or voice is good; (ii) phonosurgery if results are unsatisfactory; (iii) additional speech therapy sessions although monoplegia remains but voice is improved. The first phase was structured to support restoration of laryngeal motility (passive mobility of arytenoids) and assist glottal compensation avoiding pathological compensation, which is most likely to occur in patients who were not retrained, and the second phase was to refine the quality of voice. There is no net temporal distinction between the two phases, just a difference in the type of exercises given. The exercises consisted of: a cough attack: forced expiration with closed glottis. a cough with vowel: having the patient cough and then release a vowel (/i/ /e/ /a/ /o/). vocal function exercises: a quick and energic emission of a vowel (/i/ /e/ /a/ /o/ /u/) without hard glottal attack; quick and energic emission of occlusive dull (/ka/ /ke/ /k o/) and sonant (/ga/ /ge/ /go/) syllables; sustained intensity emission of double syllables (/kaka/ /keke/ /gog o/ /dede/) with truncation of the final vowel; sustained intensity emission of a single vowel (/aaaaa/ /eeeee/) or syllable (/kaaaa/ /kiiii/ /ghee/). All vocal function exercises were carried out using a series of maneuvers and postures suitable to facilitate the work of the patient such as:
F. Mattioli, et al B
B
B
B
3
Results of Voice Therapy in Patients With UVFP
compression of the chest: in this way, the vocalization was uttered with a quick bending downward of the chest and with arms folded. extension of the arms: the vocalization was uttered with a thrust forward of the arms with open hands or with crossed fingers and palms of the hands on the outside. laryngeal manipulations: the speech/language pathologist tried to bring the palsied hemilarynx toward the mobile one by pressing their fingers over the thyroid cartilage. This manipulation could be static (patient seated with the head in a central position) or dynamic (with the head rotated toward the side opposite from the manipulation). maneuvers against resistance: pushing (the patient, with head turned to the healthy side, had to counter the resistance of the thrust exercised by the therapist’s hand over the cheek) and lifting (the patient, in the same position, had to counter the resistance of traction exercised by the therapist’s hand over the cheek).
If we verified motility recovery and if it was necessary, treatment in the second phase was targeted to improve vocal parameters. In the case of non-motility recovery, we carried out exercises useful to avoid undesirable compensatory behaviors to obtain optimal glottal compensation. The results are given as arithmetic means ± standard deviation.
RESULTS Of the 171 patients with UVFP, 106 (62%) recovered vocal fold motility. For these 106 patients, 51/78 (65%) were treated within 4 weeks (first group; early voice treatment), 30/49 (61%) within 4–8 weeks (second group; intermediate voice treatment), and 25/44 (56%) at least 8 weeks after injury (third group; delayed voice treatment). In relation to etiology, as regards the first, second, and third groups, motility recovery was observed in 11, six, and four paralyses post-partial thyroidectomy; in 12, six, and six paralyses post-total thyroidectomy; in four, one, and two paralyses post-carotid endarterectomy; and in nine, seven, and five of idiopathic paralyses, respectively. All patients with post-traumatic (three, two, and four), postintubation (five, five, and two), post-thoracic surgery (three, two, and one), and post-neurosurgery (four, one, and one) recovered motility of the paralyzed vocal fold. The UVFP persisted after voice therapy in 65 of 171 patients (27 patients treated within 4 weeks, 19 within 4–8 weeks, and 19 after 8 weeks). In particular, in patients treated with early voice therapy, 25/27 (93%) subjects showed glottal compensation, whereas 2/27 (7%) did not have any benefit from the treatment. For intermediate voice therapy, 18/19 (95%) patients showed glottal compensation and 1/19 (5%) did not have any benefit. For delayed voice therapy, 5/19 (26%) patients showed glottal compensation, 9/19 (48%) did not have any benefit, and 5/19 (26%) had a worsened clinical condition. In the first group (early voice treatment), the patients had an MPT of 7.52 ± 3.98 deviation standard (DS) seconds before voice therapy and 14.70 ± 5.72 DS seconds after voice therapy;
the difference with the Student’s paired t-test was statistically significant (P < 0.0001). In the second group (intermediate voice treatment), the patients had an MPT of 6.71 ± 3.51 DS seconds before voice therapy and 16.57 ± 4.62 DS seconds after voice therapy; the difference with the Student’s paired t-test was statistically significant (P < 0.0001). In the third group (delayed voice treatment), the patients had an MPT of 7.18 ± 3.11 DS seconds before voice therapy and 11.57 ± 4.92 DS seconds after voice therapy; the difference with the Student’s paired t-test was not significant (P ¼ 0.01). Using the Student’s paired t-test, the results of perturbation analysis and statistical comparison of patients who did show motility recovery are given in Table 2. For the first group, an important and significant (P < 0.0001) reduction in fundamental frequency (Fo) was found; a manifest improvement was present for the mean values of Jitter (Jitt%; P ¼ 0.001), Shimmer (Shim%; P < 0.0001), and NHR (P < 0.0001). Regarding the second group, a significant (P < 0.0001) reduction in Fo was also found; a manifest improvement was present for the values of Jitt% (P < 0.001), Shim% (P < 0.0001), and NHR (P < 0.0001). For the third group, only the improvement in NHR was statistically significant (P < 0.001). DISCUSSION Vocal fold paralysis implies vocal fold immobility due to neurologic injury. The recurrent laryngeal nerve may be injured by several means such as neurologic disease, tumors, infections, trauma, iatrogenic causes, or idiopathic disease. Clinically, UVFP manifests as breathy voice, diplophonia, aspiration, or dysphagia. Treatment of UVFP is designed to eliminate aspiration and improve voice quality because there is no doubt that it is a debilitating condition affecting a patient’s general health and quality of life. There are two different treatment approaches to improve voice quality, that is, surgical therapy or voice therapy. The two main surgical options are medialization or reinnervation procedures. The first includes injection laryngoplasty and framework surgery. The second includes reinnervation by the ansa cervicalis, phrenic, or hypoglossal nerve and nerve– muscle pedicles so as to prevent denervation atrophy of the laryngeal muscles. As far as voice therapy is concerned, several techniques are widely used, such as pushing, hard glottal attack, half-swallow boom, abdominal breathing, head and neck relaxation, lip and tongue trills, resonant voice, accent method, and laryngeal manipulation.14 The results of this study emphasize the importance of early rehabilitation as demonstrated in our previous
TABLE 2. Results of Perturbation Analysis and Statistical Comparisons for Patients Who Showed Motility Recovery (n ¼ 106) First group (P) Second group (P) Third group (P)
Fo
Jitt
Shim
NHR
INTRODUCTION Unilateral vocal fold paralysis (UVFP) can be caused by unilateral damage to the vagus or recurrent laryngeal nerve.1 The etiology of the paralysis is varied and may include infections; iatrogenic trauma; malignancies; and metabolic, toxic, or idiopathic effects.2–5 UVFP is commonly encountered in clinical practice and can cause dysphonia and/or dysphagia and may be associated with aspiration pneumonia when the superior laryngeal nerve is also involved. Frequently, the paralysis resolves without treatment,6–8 and with it, the sequelae. In other cases, the paralysis persists but the voice can improve for compensation of the contralateral vocal fold. This may occur spontaneously but is facilitated by speech therapy. It has the aim of avoiding a pathological compensation between the false cords or aryteno-epiglottic folds, to obtain the most favorable position for the vocal fold paralysis, and to make the contralateral vocal fold crossing the midline more efficient. Laryngeal manipulations play an important role in logopedic rehabilitation. These manipulations also affect crico-arytenoid articulation with Accepted for publication September 25, 2014. Authors have nothing to disclose and no conflicts of interest. From the *ENT Department, University Hospital of Modena, Modena, Italy; and the ySpeech Pathologist, University Hospital of Modena, Modena, Italy. Address correspondence and reprint requests to M. Menichetti, ENT Department, University Hospital of Modena, via del Pozzo 71, Modena, Italy. E-mail: marcellamenichetti@ hotmail.it Journal of Voice, Vol. -, No. -, pp. 1-4 0892-1997/$36.00 Ó 2014 The Voice Foundation http://dx.doi.org/10.1016/j.jvoice.2014.09.027
the aim of promoting medialization of the vocal process; this passive mobilization also hinders the articulatory block, which would prevent the resumption of motility in the case of recurrent laryngeal nerve restoration. The rehabilitation treatment should start as early as possible and preferably within 4 weeks (early voice therapy), but often the patient comes too late for specialist observation so consequently the start of treatment is delayed (delayed voice therapy). In other cases, the patient accommodates the paralysis, with the paralyzed vocal fold moving to the midline or the contralateral vocal fold crossing the midline and, with this improved closure, the voice improves. In some cases, the paralysis does not improve, there is no accommodation of the paralysis, and the symptoms persist. These patients often receive voice and swallowing therapy and many undergo surgery to improve closure.6 Voice therapy is the treatment of choice in patients with UVFP9 and it can be started immediately, in the first 4 weeks after the appearance of paralysis (early voice therapy), within 4–8 weeks (intermediate voice therapy), or after 8 weeks (delayed voice therapy).10 In the case of unsatisfactory results for the persistence of UVFP with the presence of a glottic gap, in the early stages of paralysis, we usually resort to phonosurgery based on injection procedures with absorbable materials, considering the potential reversibility of the paralysis, and using non-adsorbable materials in the case of more than 12 months of paralysis. The use of early injection laryngoplasty has many supporters in recent literature.11–13 As may be expected, early voice therapy plays an important role in the therapeutic procedure. In the case
2 of an unsatisfactory functional result, laryngoplasty with a resorbable material is used 2 or 3 months after the onset of paralysis. From this perspective, patients with UVFP are prioritized in our phoniatric and logopedic service. The aim of this study was to compare, in terms of vocal improvement and motility recovery, the post-vocal treatment results of our patients with UVFP who started early treatment versus intermediate or delayed treatment. All patients underwent forcible exercises supplemented by manipulations and maneuvers. Our aim was to emphasize the importance of early rehabilitation as demonstrated in our previous work.2 MATERIALS AND METHODS We performed a prospective study of all patients with UVFP between October 2004 and October 2013. A total of 171 patients were treated in our outpatient clinics for Voice Analysis and Rehabilitation and all were included in our study. We excluded from the data analysis 40 patients who had not completed our multidimensional diagnostic-therapeutic assessment. Of the 171 patients, 78 (56 women; 22 men) underwent early voice treatment, 49 (37 women; 12 men) received intermediate voice treatment, and 44 (23 women; 21 men) underwent delayed voice treatment. In the first group, median age was 57 years (range, 19–87 years), in the second, mean age was 55 years (range, 18–82 years), whereas in the third group, median age was 55.5 years (range, 17–82 years). Speech-language pathologists and an otolaryngologist evaluated all patients. The etiology of the paralysis was extensive and varied and this is reported in Table 1. A voice evaluation was performed with a complete head and neck examination and a detailed video-strobolaryngoscopic evaluation of glottal configuration during phonation. Rigid (Storz 90 rigid telescope) and flexible (Pentax FNL 10RP3 fiberscope) endoscopes were used. Videostrobolaryngoscopic evaluation was essential to document the vocal fold position, motility, and morphology, and observe its prolonged vibratory characteristics. The examiner asked the patient to produce an /a/ sound for as long as possible; the voice signal was recorded and stored digitally. Computerized Speech Lab (CSL) version 5.05 software with the 4300B external module (Kay Elemetrics Corporation, Lincoln Park, NJ) was used. It was also important to determine the maximum phonation time (MPT), the longest sustained /a/ sound. Spectrography was performed on the 3-second sustained vowel /a/ sound and the Italian word /aiuole/ (flowerbeds in English). Yanagihara’s classification was used to rate the voice spectrograms adapted to the single vowel /a/. Jitter (Jitt%), Shimmer (Shim%), noise-to-harmonic ratio (NHR), and fundamental frequency (Fo) were calculated. Voice therapy Each patient involved in this study underwent several voice therapy sessions twice a week with an experienced speech/
Journal of Voice, Vol. -, No. -, 2014
TABLE 1. Etiology of UVFP for Patients in This Study
Etiology Thyroid alcoholization Thoracic aorta aneurysm Spastic ataxia Lung carcinoma Carotid endarterectomy Mediastinal surgery Tracheal surgery Vagal neuroma Neurosurgery Inflammation Idiopathic Viral infection Post-intubation Partial thyroidectomy Total thyroidectomy Traumatic
Treated Treated Treated After From Within 4 wk 4 to 8 wk 8 wk Total 1
0
0
1
1
0
1
2
1 2 7
0 0 1
0 1 2
1 3 10
2 1 1 3 0 13 0 5 22 16 3
3 1 0 0 1 11 1 5 12 12 2
1 1 1 0 0 9 0 2 10 16 0
6 3 2 3 1 33 1 12 44 44 5
language pathologist, and the exercises were repeated daily at home during the treatment period. We usually suggest 12/18 sessions, followed by laryngoscopy, or earlier if the speech pathologist suspects restoration of motility should the voice suddenly improve. At the end of treatment, we decide the next strategy. This may include: (i) discontinuation of treatment if the larynx is mobile or voice is good; (ii) phonosurgery if results are unsatisfactory; (iii) additional speech therapy sessions although monoplegia remains but voice is improved. The first phase was structured to support restoration of laryngeal motility (passive mobility of arytenoids) and assist glottal compensation avoiding pathological compensation, which is most likely to occur in patients who were not retrained, and the second phase was to refine the quality of voice. There is no net temporal distinction between the two phases, just a difference in the type of exercises given. The exercises consisted of: a cough attack: forced expiration with closed glottis. a cough with vowel: having the patient cough and then release a vowel (/i/ /e/ /a/ /o/). vocal function exercises: a quick and energic emission of a vowel (/i/ /e/ /a/ /o/ /u/) without hard glottal attack; quick and energic emission of occlusive dull (/ka/ /ke/ /k o/) and sonant (/ga/ /ge/ /go/) syllables; sustained intensity emission of double syllables (/kaka/ /keke/ /gog o/ /dede/) with truncation of the final vowel; sustained intensity emission of a single vowel (/aaaaa/ /eeeee/) or syllable (/kaaaa/ /kiiii/ /ghee/). All vocal function exercises were carried out using a series of maneuvers and postures suitable to facilitate the work of the patient such as:
F. Mattioli, et al B
B
B
B
3
Results of Voice Therapy in Patients With UVFP
compression of the chest: in this way, the vocalization was uttered with a quick bending downward of the chest and with arms folded. extension of the arms: the vocalization was uttered with a thrust forward of the arms with open hands or with crossed fingers and palms of the hands on the outside. laryngeal manipulations: the speech/language pathologist tried to bring the palsied hemilarynx toward the mobile one by pressing their fingers over the thyroid cartilage. This manipulation could be static (patient seated with the head in a central position) or dynamic (with the head rotated toward the side opposite from the manipulation). maneuvers against resistance: pushing (the patient, with head turned to the healthy side, had to counter the resistance of the thrust exercised by the therapist’s hand over the cheek) and lifting (the patient, in the same position, had to counter the resistance of traction exercised by the therapist’s hand over the cheek).
If we verified motility recovery and if it was necessary, treatment in the second phase was targeted to improve vocal parameters. In the case of non-motility recovery, we carried out exercises useful to avoid undesirable compensatory behaviors to obtain optimal glottal compensation. The results are given as arithmetic means ± standard deviation.
RESULTS Of the 171 patients with UVFP, 106 (62%) recovered vocal fold motility. For these 106 patients, 51/78 (65%) were treated within 4 weeks (first group; early voice treatment), 30/49 (61%) within 4–8 weeks (second group; intermediate voice treatment), and 25/44 (56%) at least 8 weeks after injury (third group; delayed voice treatment). In relation to etiology, as regards the first, second, and third groups, motility recovery was observed in 11, six, and four paralyses post-partial thyroidectomy; in 12, six, and six paralyses post-total thyroidectomy; in four, one, and two paralyses post-carotid endarterectomy; and in nine, seven, and five of idiopathic paralyses, respectively. All patients with post-traumatic (three, two, and four), postintubation (five, five, and two), post-thoracic surgery (three, two, and one), and post-neurosurgery (four, one, and one) recovered motility of the paralyzed vocal fold. The UVFP persisted after voice therapy in 65 of 171 patients (27 patients treated within 4 weeks, 19 within 4–8 weeks, and 19 after 8 weeks). In particular, in patients treated with early voice therapy, 25/27 (93%) subjects showed glottal compensation, whereas 2/27 (7%) did not have any benefit from the treatment. For intermediate voice therapy, 18/19 (95%) patients showed glottal compensation and 1/19 (5%) did not have any benefit. For delayed voice therapy, 5/19 (26%) patients showed glottal compensation, 9/19 (48%) did not have any benefit, and 5/19 (26%) had a worsened clinical condition. In the first group (early voice treatment), the patients had an MPT of 7.52 ± 3.98 deviation standard (DS) seconds before voice therapy and 14.70 ± 5.72 DS seconds after voice therapy;
the difference with the Student’s paired t-test was statistically significant (P < 0.0001). In the second group (intermediate voice treatment), the patients had an MPT of 6.71 ± 3.51 DS seconds before voice therapy and 16.57 ± 4.62 DS seconds after voice therapy; the difference with the Student’s paired t-test was statistically significant (P < 0.0001). In the third group (delayed voice treatment), the patients had an MPT of 7.18 ± 3.11 DS seconds before voice therapy and 11.57 ± 4.92 DS seconds after voice therapy; the difference with the Student’s paired t-test was not significant (P ¼ 0.01). Using the Student’s paired t-test, the results of perturbation analysis and statistical comparison of patients who did show motility recovery are given in Table 2. For the first group, an important and significant (P < 0.0001) reduction in fundamental frequency (Fo) was found; a manifest improvement was present for the mean values of Jitter (Jitt%; P ¼ 0.001), Shimmer (Shim%; P < 0.0001), and NHR (P < 0.0001). Regarding the second group, a significant (P < 0.0001) reduction in Fo was also found; a manifest improvement was present for the values of Jitt% (P < 0.001), Shim% (P < 0.0001), and NHR (P < 0.0001). For the third group, only the improvement in NHR was statistically significant (P < 0.001). DISCUSSION Vocal fold paralysis implies vocal fold immobility due to neurologic injury. The recurrent laryngeal nerve may be injured by several means such as neurologic disease, tumors, infections, trauma, iatrogenic causes, or idiopathic disease. Clinically, UVFP manifests as breathy voice, diplophonia, aspiration, or dysphagia. Treatment of UVFP is designed to eliminate aspiration and improve voice quality because there is no doubt that it is a debilitating condition affecting a patient’s general health and quality of life. There are two different treatment approaches to improve voice quality, that is, surgical therapy or voice therapy. The two main surgical options are medialization or reinnervation procedures. The first includes injection laryngoplasty and framework surgery. The second includes reinnervation by the ansa cervicalis, phrenic, or hypoglossal nerve and nerve– muscle pedicles so as to prevent denervation atrophy of the laryngeal muscles. As far as voice therapy is concerned, several techniques are widely used, such as pushing, hard glottal attack, half-swallow boom, abdominal breathing, head and neck relaxation, lip and tongue trills, resonant voice, accent method, and laryngeal manipulation.14 The results of this study emphasize the importance of early rehabilitation as demonstrated in our previous
TABLE 2. Results of Perturbation Analysis and Statistical Comparisons for Patients Who Showed Motility Recovery (n ¼ 106) First group (P) Second group (P) Third group (P)
Fo
Jitt
Shim
NHR
