DYSPHONIA DUE TO ISOLATED CRICOTHYROID … 1. Comparison of acoustic parameters before and after...
1
Table 1. Comparison of acoustic parameters before and after botulinum toxin injection into the CT muscle. DYSPHONIA DUE TO ISOLATED CRICOTHYROID MUSCLE DYSTONIA: A CASE REPORT AND REVIEW OF LITERATURE Shannon Kraft MD 1 , Jana Childes CCC-SLP 1 , Allen Hillel MD 2 and Joshua Schindler MD 1 1 Oregon Health and Sciences University, Department of Otolaryngology, Portland, OR 2 University of Washington, Department of Otolaryngology, Seattle, WA Purpose: We report a case of laryngeal dystonia resulting from isolated cricothyroid (CT) muscle dysfunction. Methods: We discuss the pertinent clinical features, stroboscopy, laryngeal function studies, and electromyography (EMG) findings of the case, and review the literature. Summary: The patient, a 43 year old otherwise healthy physician, presented with eight months of progressive hoarseness. Her symptoms were particularly bothersome while dictating. At her initial exam, her voice was rated Grade 3, Roughness 3, Breathiness 1, Asthenia 0, Strain 3. (G3R3B1A0S3). Videostroboscopy was unremarkable. A course of voice rest and corticosteroids failed to improve her voice. Subsequent trials of speech therapy were unsuccessful. No evidence of sulcus vocalis or mucosal bridge was identified during microdirect laryngoscopy. The patient was referred for EMG. The thyroarytenoid and interarytenoid muscles had normal latencies (300 msec) on sustained vowel, while the CT muscle had an increased latency of 750 msec in all vocal tasks. One month after CT injection with 3 units of botulinum toxin, her voice was rated G1R1B0A0S1. Voice Handicap Index (VHI) improved from 87 to 35. Fundamental frequency decreased from 287 Hz to 212 Hz. Conclusions: EMG can be a useful adjunct in the diagnosis of dysphonia that persists despite adequate trials of speech therapy. To our knowledge, this is the only report of laryngeal dystonia due to isolated cricothyroid dysfunction. Abstract Spasmodic dysphonia (SD) is characterized by sustained or repetitive involuntary muscle contractions of intrinsic laryngeal muscles during voicing. 1 Patients with SD are evaluated and divided into clinical subtypes based upon perceptual voice analysis. Treatment with botulinum toxin is directed toward the predominate muscle responsible for the clinical subtype. 2 Adductor spasmodic dysphonia (ADSD) accounts for about 85% of patients and is treated by thyroarytenoid (TA) injection. Patients with abductor spasmodic dysphonia (ABSD) are treated with posterior cricoarytenoid (PCA) injection. 4 Although perceived clinically as ADSD or ABSD, electromyography (EMG) suggests SD is a disorder of mixed abductor and adductor dysfunction (MXD SD) with a predominant phenotype. 4 EMG has demonstrated that the lateral cricoarytenoid (LCA) and interarytenoid (IA) can also contribute to ADSD. 5 In patients where the IA was determined to be overactive, treatment of the IA in addition to the TA resulted in improved symptom control. 6 The authors concluded that EMG could be used to generate a “road map” by which to design a plan for targeted therapy for patients with refractory SD. Background Because no classic abductor or adductor breaks were noted on her initial exam, our patient underwent voice therapy to address a possible functional component. Muscle tension dysphonia (MTD) is a functional disorder in which excessive tension of the intrinsic and extrinsic laryngeal muscles results in hoarseness. 9,10 The hallmarks of MTD include presence in all vocal tasks and videostroboscopic findings. Mutational falsetto, (puberphonia) is a rare functional disorder characterized by failure to demonstrate the expected drop in vocal pitch at puberty despite the development of a normal adult male larynx. 12 Characteristic of functional disorders, both are responsive to directed voice therapy. 13,14,15 Despite multiple trials of voice therapy, our patient was never able to produce a normal voice, indicating this was not a functional disorder. The failure of our patient to improve with therapy led us to consider a neurologic cause for her dysphonia. The utility of EMG in diagnosing dysphonia is a topic of great debate. A systematic literature review by Sataloff et al identified only four articles that investigated EMG as a diagnostic tool for SD. 16 The largest series (Hillel’s 2001) defined EMG differences between normal and SD patients. The latency between electrical activity and the onset of phonation were significantly longer in SD, leading the authors to conclude that latencies greater than 400 msec are abnormal. In 2009, the Neurolaryngology Study Group looked again at the diagnostic validity of EMG and determined that its usefulness remained in question. 17 Since then, 137 studies about laryngeal EMG in humans have been published, only one of which specifically investigated the role of EMG in evaluating SD. Latency values were noted to correlate with the degree of dysphonia in patients with ADSD, with average latency measuring 332 msec in mild ADSD, 426 msec in moderate ADSD and 792 msec in severe SD. 18 Prolonged CT latencies (750 msec) led us to conclude the patient’s dysphonia was due dystonic activity. She was offered a trial of botulinum toxin injection. The precedent for CT injection is mostly in the context of ABSD. In a series of 32 patients, nine patients with refractory abductor symptoms were injected in the CT in addition to the PCA, leading to improvement in overall symptoms score. 21 Ludlow et al reported over-activity of the CT on EMG in a series of 10 patients with ABSD. After treating the PCA and CT with botulinum toxin, all patients demonstrated improvement in their acoustic parameters. Because the EMG data available indicated aberrant activity in the CT only, the CT muscles were treated bilaterally with 3 units of botulinum toxin. Consistent with a history of dystonia, her voice complaints began to return at approximately five to six months after her initial injection. She elected to continue with periodic injections and continues to do well. Discussion REFERENCES: 1 Schapira AH. Chapter 372. Parkinson's Disease and Other Movement Disorders. In: Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison's Principles of Internal Medicine. 18th ed. New York: McGraw-Hill; 2012. http://www.accessmedicine.com.liboff.ohsu.edu/content.aspx?aID=9146448. Accessed January 12, 2013. 2 Aronson A and Bless D. Spasmodic Dysphonia. In Clinical Voice Disorders (4th Ed)., New York, Thieme Medical Publishers Inc., 2009; 101-133. 4 Hillel AD. The study of laryngeal muscle activity in normal human subjects and in patients with laryngeal dystonia using multiple fine wire electromyography. Laryngoscope 2001; 111 (suppl 97). 5 Klotz DA, Maronian NC, Waugh PF. Findings of multiple muscle involvement in a study of 214 patients with laryngeal dystonia using fine-wire electromyography. Ann Otol Rhinol Laryngol 2004; 113: 602-612. 6 Hillel AD, Maronian NC, Robinson L, et al. Treatment of the interarytenoid muscle with botulinum toxin for laryngeal dystonia. Ann Otol Rhinol Laryngol 2004; 113: 341-348. 9 Morrison MD, Nichol H and Rammage LA. Diagnostic criteria in functional dysphonia. Laryngoscope. 1986; 96: 1-8. 10 Koufman JA, Blalock PD. Classification and approach to patients with functional voice disorders. Ann Otol Rhinol Laryngol. 1982; 91: 372-377 12 Rubin J, Sataloff R, Korovin G. Diagnosis and Treatment of Voice Disorders, 3rd ed. San Diego, Ca: Plural Publishing, Inc.; 2006. 13 MacKenzie K, Millar A, Wilson JA et al. Is voice therapy an effective treatment for dysphonia? A randomized controlled trial. Br Med J. 2001; 323: 658-661. 14 Carding PM, Horsley IA, Docherty GJ. A study of the effectiveness of voice therapy in the treatment of 45 patients with nonorganic dysphonia. J Voice. 1999;13:72-104. 15 Dagli M, Sati I, Acar A, Stone RE Jr, Dursun G and Eryilmaz A. Mutational falsetto: intervention outcomes in 45 patients. J Laryngol Otol 2008;122: 277-81. 16 Sataloff RT, Mandel S, Mann EA and Ludlow CL. Practice Parameter: Laryngeal electromyography (an evidence based-review). Otolaryngol Head Neck Surg 2004; 130: 770-779. 17 Blitzer A, Crumley RL, Dailey SH et al. Recommendations of the Neurolaryngology Study Group on laryngeal electromyography. Otolaryngol Head Neck Surg 2009; 140:782-793. 18 Di Biase NG, Korn GP, Lorenzon P et al. Dysphonia severity degree and phonation onset latency in laryngeal adductor dystonia. J Voice 2010; 24(4):406-9. 21 Blitzer A, Brin MF, Stewart C, Aviv JE and Fahn S. Abductor Laryngeal Dystonia: A Series Treated with Botulinum Toxin. Laryngoscope 1992; 102: 163-167. Figure 2. Fine wire EMG. Channel 1 = Voice, Channel 3 = TA, Channel 5 = LCA and Channel 7 = CT. Fig 1A. Patient glides from low pitch to high pitch using a sustained “eee.” CT recruitment at higher pitches confirms wire placement in the CT. Fig 1B. Sustained “eee”. The TA and LCA demonstrate normal latencies of approximately 400 msec. CT latency is 750 msec, nearly twice the normal value. Figure 3. Fine wire EMG. Channel 1 = Voice, Channel 3 = TA, Channel 5 = LCA and Channel 7 = CT. Fig 2A. Repeated “ee, ee,ee”. Prolonged CT latency and increased CT activity is noted. Fig 2B. “We mow our lawn all year.” CT latency is approximately 650 msec with increased activity throughout the task. VHI MPT F0 (Hz) Fmin (Hz) Fmax (Hz) Pre-BTX 87 11 287 151 650 Post-BTX 35 10 212 145 518 • An otherwise healthy 43 year old female physician with 8 months of progressive dysphonia • Worse on phone when dictating • Better with whispering • Normal videostroboscopy • Failed trial of voice rest and steroids • Failed multiple trials of voice therapy • No pathology at time of microlaryngoscopy Case Report 37.jpg GO TO http://www.youtube.com/watch?v=qggJORPgKVQ TO HEAR PRE-TREATMENT AUDIO GO TO http://www.youtube.com/watch?v=CSqnTuC3oDw TO SEE PRE-TREATMENT STROBOSCOPY GO TO http://www.youtube.com/watch?v=X9rGratfggE TO HEAR POST-TX AUDIO EMG can be a useful tool in identifying the specific muscle(s) contributing to the vocal pathology when other methods of evaluation and treatment have failed. EMG allowed us to generate a “road map” of aberrant muscle activity and to tailor a treatment plan for what we believe to be the first reported cased of isolated cricothyroid dystonia successfully treated with botulinum toxin. CT dystonia should be considered in dysphonia characterized by elevated pitch that does not respond to voice therapy. Conclusions
Transcript of DYSPHONIA DUE TO ISOLATED CRICOTHYROID … 1. Comparison of acoustic parameters before and after...
Table 1. Comparison of acoustic parameters before and after botulinum toxin injection into the CT muscle.
DYSPHONIA DUE TO ISOLATED CRICOTHYROID MUSCLE DYSTONIA:
A CASE REPORT AND REVIEW OF LITERATURE Shannon Kraft MD1, Jana Childes CCC-SLP1, Allen Hillel MD2 and Joshua Schindler MD1
1Oregon Health and Sciences University, Department of Otolaryngology, Portland, OR 2University of Washington, Department of Otolaryngology, Seattle, WA
Purpose: We report a case of laryngeal dystonia resulting from isolated cricothyroid (CT) muscle dysfunction. Methods: We discuss the pertinent clinical features, stroboscopy, laryngeal function studies, and electromyography (EMG) findings of the case, and review the literature. Summary: The patient, a 43 year old otherwise healthy physician, presented with eight months of progressive hoarseness. Her symptoms were particularly bothersome while dictating. At her initial exam, her voice was rated Grade 3, Roughness 3, Breathiness 1, Asthenia 0, Strain 3. (G3R3B1A0S3). Videostroboscopy was unremarkable. A course of voice rest and corticosteroids failed to improve her voice. Subsequent trials of speech therapy were unsuccessful. No evidence of sulcus vocalis or mucosal bridge was identified during microdirect laryngoscopy. The patient was referred for EMG. The thyroarytenoid and interarytenoid muscles had normal latencies (300 msec) on sustained vowel, while the CT muscle had an increased latency of 750 msec in all vocal tasks. One month after CT injection with 3 units of botulinum toxin, her voice was rated G1R1B0A0S1. Voice Handicap Index (VHI) improved from 87 to 35. Fundamental frequency decreased from 287 Hz to 212 Hz. Conclusions: EMG can be a useful adjunct in the diagnosis of dysphonia that persists despite adequate trials of speech therapy. To our knowledge, this is the only report of laryngeal dystonia due to isolated cricothyroid dysfunction.
Abstract
Spasmodic dysphonia (SD) is characterized by sustained or repetitive involuntary muscle contractions of intrinsic laryngeal muscles during voicing.1 Patients with SD are evaluated and divided into clinical subtypes based upon perceptual voice analysis. Treatment with botulinum toxin is directed toward the predominate muscle responsible for the clinical subtype.2 Adductor spasmodic dysphonia (ADSD) accounts for about 85% of patients and is treated by thyroarytenoid (TA) injection. Patients with abductor spasmodic dysphonia (ABSD) are treated with posterior cricoarytenoid (PCA) injection.4 Although perceived clinically as ADSD or ABSD, electromyography (EMG) suggests SD is a disorder of mixed abductor and adductor dysfunction (MXD SD) with a predominant phenotype.4 EMG has demonstrated that the lateral cricoarytenoid (LCA) and interarytenoid (IA) can also contribute to ADSD.5 In patients where the IA was determined to be overactive, treatment of the IA in addition to the TA resulted in improved symptom control.6 The authors concluded that EMG could be used to generate a “road map” by which to design a plan for targeted therapy for patients with refractory SD.
Background
Because no classic abductor or adductor breaks were noted on her initial exam, our patient underwent voice therapy to address a possible functional component. Muscle tension dysphonia (MTD) is a functional disorder in which excessive tension of the intrinsic and extrinsic laryngeal muscles results in hoarseness.9,10 The hallmarks of MTD include presence in all vocal tasks and videostroboscopic findings. Mutational falsetto, (puberphonia) is a rare functional disorder characterized by failure to demonstrate the expected drop in vocal pitch at puberty despite the development of a normal adult male larynx.12 Characteristic of functional disorders, both are responsive to directed voice therapy.13,14,15 Despite multiple trials of voice therapy, our patient was never able to produce a normal voice, indicating this was not a functional disorder. The failure of our patient to improve with therapy led us to consider a neurologic cause for her dysphonia. The utility of EMG in diagnosing dysphonia is a topic of great debate. A systematic literature review by Sataloff et al identified only four articles that investigated EMG as a diagnostic tool for SD.16 The largest series (Hillel’s 2001) defined EMG differences between normal and SD patients. The latency between electrical activity and the onset of phonation were significantly longer in SD, leading the authors to conclude that latencies greater than 400 msec are abnormal. In 2009, the Neurolaryngology Study Group looked again at the diagnostic validity of EMG and determined that its usefulness remained in question.17 Since then, 137 studies about laryngeal EMG in humans have been published, only one of which specifically investigated the role of EMG in evaluating SD. Latency values were noted to correlate with the degree of dysphonia in patients with ADSD, with average latency measuring 332 msec in mild ADSD, 426 msec in moderate ADSD and 792 msec in severe SD.18 Prolonged CT latencies (750 msec) led us to conclude the patient’s dysphonia was due dystonic activity. She was offered a trial of botulinum toxin injection. The precedent for CT injection is mostly in the context of ABSD. In a series of 32 patients, nine patients with refractory abductor symptoms were injected in the CT in addition to the PCA, leading to improvement in overall symptoms score.21 Ludlow et al reported over-activity of the CT on EMG in a series of 10 patients with ABSD. After treating the PCA and CT with botulinum toxin, all patients demonstrated improvement in their acoustic parameters. Because the EMG data available indicated aberrant activity in the CT only, the CT muscles were treated bilaterally with 3 units of botulinum toxin. Consistent with a history of dystonia, her voice complaints began to return at approximately five to six months after her initial injection. She elected to continue with periodic injections and continues to do well.
Discussion
REFERENCES: 1 Schapira AH. Chapter 372. Parkinson's Disease and Other Movement Disorders. In: Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison's Principles of Internal Medicine. 18th ed. New York: McGraw-Hill; 2012. http://www.accessmedicine.com.liboff.ohsu.edu/content.aspx?aID=9146448. Accessed January 12, 2013. 2 Aronson A and Bless D. Spasmodic Dysphonia. In Clinical Voice Disorders (4th Ed)., New York, Thieme Medical Publishers Inc., 2009; 101-133. 4 Hillel AD. The study of laryngeal muscle activity in normal human subjects and in patients with laryngeal dystonia using multiple fine wire electromyography. Laryngoscope 2001; 111 (suppl 97). 5 Klotz DA, Maronian NC, Waugh PF. Findings of multiple muscle involvement in a study of 214 patients with laryngeal dystonia using fine-wire electromyography. Ann Otol Rhinol Laryngol 2004; 113: 602-612. 6 Hillel AD, Maronian NC, Robinson L, et al. Treatment of the interarytenoid muscle with botulinum toxin for laryngeal dystonia. Ann Otol Rhinol Laryngol 2004; 113: 341-348. 9 Morrison MD, Nichol H and Rammage LA. Diagnostic criteria in functional dysphonia. Laryngoscope. 1986; 96: 1-8. 10 Koufman JA, Blalock PD. Classification and approach to patients with functional voice disorders. Ann Otol Rhinol Laryngol. 1982; 91: 372-377 12 Rubin J, Sataloff R, Korovin G. Diagnosis and Treatment of Voice Disorders, 3rd ed. San Diego, Ca: Plural Publishing, Inc.; 2006. 13 MacKenzie K, Millar A, Wilson JA et al. Is voice therapy an effective treatment for dysphonia? A randomized controlled trial. Br Med J. 2001; 323: 658-661. 14 Carding PM, Horsley IA, Docherty GJ. A study of the effectiveness of voice therapy in the treatment of 45 patients with nonorganic dysphonia. J Voice. 1999;13:72-104. 15 Dagli M, Sati I, Acar A, Stone RE Jr, Dursun G and Eryilmaz A. Mutational falsetto: intervention outcomes in 45 patients. J Laryngol Otol 2008;122: 277-81. 16 Sataloff RT, Mandel S, Mann EA and Ludlow CL. Practice Parameter: Laryngeal electromyography (an evidence based-review). Otolaryngol Head Neck Surg 2004; 130: 770-779. 17 Blitzer A, Crumley RL, Dailey SH et al. Recommendations of the Neurolaryngology Study Group on laryngeal electromyography. Otolaryngol Head Neck Surg 2009; 140:782-793. 18 Di Biase NG, Korn GP, Lorenzon P et al. Dysphonia severity degree and phonation onset latency in laryngeal adductor dystonia. J Voice 2010; 24(4):406-9. 21 Blitzer A, Brin MF, Stewart C, Aviv JE and Fahn S. Abductor Laryngeal Dystonia: A Series Treated with Botulinum Toxin. Laryngoscope 1992; 102: 163-167.
Figure 2. Fine wire EMG. Channel 1 = Voice, Channel 3 = TA, Channel 5 = LCA and Channel 7 = CT. Fig 1A. Patient glides from low pitch to high pitch using a sustained “eee.” CT recruitment at higher pitches confirms wire placement in the CT. Fig 1B. Sustained “eee”. The TA and LCA demonstrate normal latencies of approximately 400 msec. CT latency is 750 msec, nearly twice the normal value.
Figure 3. Fine wire EMG. Channel 1 = Voice, Channel 3 = TA, Channel 5 = LCA and Channel 7 = CT. Fig 2A. Repeated “ee, ee,ee”. Prolonged CT latency and increased CT activity is noted. Fig 2B. “We mow our lawn all year.” CT latency is approximately 650 msec with increased activity throughout the task.
VHI MPT F0 (Hz) Fmin (Hz) Fmax (Hz)
Pre-BTX 87 11 287 151 650 Post-BTX 35 10 212 145 518
• An otherwise healthy 43 year old female physician with 8 months of progressive dysphonia • Worse on phone when dictating • Better with whispering
• Normal videostroboscopy • Failed trial of voice rest and steroids • Failed multiple trials of voice therapy • No pathology at time of microlaryngoscopy
Case Report
37.jpg
GO TO http://www.youtube.com/watch?v=qggJORPgKVQ TO HEAR PRE-TREATMENT AUDIO GO TO http://www.youtube.com/watch?v=CSqnTuC3oDw TO SEE PRE-TREATMENT STROBOSCOPY
GO TO http://www.youtube.com/watch?v=X9rGratfggE TO HEAR POST-TX AUDIO
EMG can be a useful tool in identifying the specific muscle(s) contributing to the vocal pathology when other methods of evaluation and treatment have failed. EMG allowed us to generate a “road map” of aberrant muscle activity and to tailor a treatment plan for what we believe to be the first reported cased of isolated cricothyroid dystonia successfully treated with botulinum toxin. CT dystonia should be considered in dysphonia characterized by elevated pitch that does not respond to voice therapy.
Conclusions
