Do we cause dysphagia when treating spasmodic dysphonia with botox?

Do we cause dysphagia when treating spasmodic dysphonia with botox? | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Do we cause dysphagia when treating spasmodic dysphonia with botox? Esma Altan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5967904/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objectives: Spasmodic dysphonia (SD) is a neurological movement disorder involving the laryngeal muscles. There are three main types: adductor, abductor and mixed type. adductor type is the most common and mixed type is the rarest. Botox is the gold standard in treatment, botox is applied to the affected muscle group according to the type of spasmodic dysphonia. Dysphagia often occurs as a side effect of treatment (botulinum toxin injection) in spasmodic dystonia. Sometimes dysphagia may be seen secondary to spasmodic dysphonia. Methods: This study included 8 patients with adductor spasmodic dysphonia and 8 without dysphagia and 8 healthy subjects. Swallowing evaluation of both groups was performed by FEES, EMG and ultrasound. Results: Swallowing functions of patients with adductor spasmodic dysphonia were re-evaluated after botox injection into the thyroarytenoid muscle. No significant difference was observed in both groups Conclusion: In our study, our patient group consisted of patients with spasmodic dysphonia without dysphagia and dysphagia was not observed in patients evaluated with FEES, EMG and ultrasound after Botox. Otorhinolaryngology Swallowing Dysphagia Voice Dysphonia Laryngeal Dystonia Tremor INTRODUCTION Spasmodic dysphonia (SD) or laryngeal dystonia is a neurologic disorder that causes voice disorders with involuntary intermittent contraction of intrinsic laryngeal muscles ( 1 , 2 ). According to the muscles involved, there are forms of SD: adductor, abductor and mixed. Adductor SD (ADSD) is characterized by an effortful and strained voice as if choking by contracting the muscles that provide adduction and blocking the airflow. In abductor SD (ABSD), the cords due to abduction do not close during phonation and are associated with dyspnea and aphonia ( 3 , 4 ). ADSD is the most common type in the clinic, mixed type is less common and it is difficult to diagnose ( 5 ). Treatment of SD; involves the injection of botulinum toxin (BT) into the thyroarytenoid muscle in the adductor type and the posterior cricoarytenoid muscle in the abductor type, sometimes under electomyography guidance, and sometimes surgical procedures and voice therapy. Botox injection is the gold standard. Botox prevents muscle contractions by binding to acetylcholine receptors at the neuromuscular junction and inhibiting its release. Surgical techniques include type 2 thyroplasty ( 6 , 7 ), myectomy (thyroarytenoid muscle) ( 8 ) and selective laryngeal denervation-reinnervation ( 9 ). These surgical treatments are used in the adductor type. Voice therapy is a part of the treatment but its effectiveness is limited, therapy can be used together with other treatments. Swallowing has some phases; it is a complex behavior that takes place with the work of oral, pharyngeal, and esophageal muscles ( 10 , 11 ). Dysphagia can be defined as the difficulty encountered by the food that starts with chewing in the mouth and goes all the way to the stomach. Oral dysphagia can be defined as any difficulty in the preparation of a bolus. Pharyngeal dysphagia may be caused by absence or delay in swallowing reflex and esophageal dysphagia may be caused by esophageal or sphincter disorder ( 10 , 12 ). Dysphagia can also occur due to Botox, usually after treatment for spasmodic dystonia (botulinum toxin injection).It is defined as one of the most common side effects after botox injection in cervical dystonias and spasmodic dysphonias and the incidence rate is between 10–90% ( 13 – 15 ) and injections using USG and EMG can reduce these side effects ( 14 ). Very few studies have evaluated swallowing before and after treatment ( 16 – 18 ). Many studies have not focused much on dysphagia secondary to Botox. ( 19 – 21 ) Especially, involuntary pharyngeal phase of swallowing is affected and premature leak is seen with fluids. This condition, which can be treated with diet modifications, is often overlooked because it is transient. There is no study to evaluate as multimodal and objective of the effect of botulinum toxin on swallowing function in these patients. Therefore, we aimed to evaluate swallowing functions of patients with spasmodic dystonia without dysphagia symptom and to investigate the effect of botulinum toxin treatment on swallowing function. MATERIAL AND METHOD The Clinical Research Ethics Committee (Date:October 2023, Decision No:597) approved before the research began. We obtained informed consent from all participants. Participants A total of 16 subjects consisting of 8 patients with spasmodic dysphonia and without dysphagia symptoms, who were planned to undergo botulinum toxin injection into their thyroaritenoid muscles and 8 healthy volunteers with age and gender matched these patients were included in the study. Subjects who had any metabolic/endocrine and progressive central or peripheral nervous system diseases and had past surgical history or using drug that can cause cause swallowing dysfunction were excluded from the study. In addition, patients with multifocal or segmental dystonia and who described difficulty in swallowing were excluded from the study. Botulinum Toxin Injection In spasmodic dysphonia, involuntary closure of the vocal cords causes speech difficulties. The gold standard treatment for these patients is periodic injections of botulinum toxin A (BTX-A) into these muscles to prevent them from contracting involuntarily. In the adductor type, the improvement in voice after Botox is 8.0–15.1 weeks. ( 32 – 34 ) Commonly reported side effects of BTX-A injections include a slightly breathy voice (25–35% of patients) and cough or dysphagia, especially with liquids (10% of patients). The dose and timing of the patient's next injection is determined by the patient's side effects .( 35 ) In our study patients with adductor type spasmodic dysphonia were injected with 2.5 units of onabotulinum toxin Type A (Botox®) botulinum toxin into both thyroarytenoid muscles with EMG guidance After treatment, patients' satisfaction was questioned by Likert scale as “I am satisfied”, “I am not satisfied” and “I am not satisfied nor satisfied”. Assessment Tools First, demographic and disease characteristics were obtained from all participants. Then, fiberoptic endoscopic evaluation, swallowing electrophysiology and ultrasonographic evaluation were performed to evaluate swallowing functions. Demographic and disease characteristics: Patients and volunteers, including age, gender and educational status, as well as dystonia duration of patients were recorded. Swallowing evaluation: The following three assessment methods were used to evaluate the swallowing functions of the participants. Fiberoptic Endoscopic Evaluation Swallowing Electrophysiology Ultrasonographic Evaluation a) Flexible Fiberoptic Endoscopic Evaluation of Swallowing (FEES ): The most important and gold standard diagnostic methods for the diagnosis of dysphagia (OD) are FEES and videofluoroscopic swallowing study (VFSS). ( 22 ). The advantages of FEES are that it can be performed in any environment including the patient's bedside, it has no radiation effect, and its disadvantages are that the passage cannot be seen clearly when the pharynx is closed during swallowing ( 22 ). Endoscopic evaluation of the patients was performed by the same specialist, with the patient in a sitting position, using a 3.4 mm diameter channelless fiberoptic nasopharyngoscope, light source, camera, monitor and DVD recorder (KarlStorz GmbH & Co KG, Tuttlingen, Germany). Local anesthetics were not used during this test. Water aspiration or penetration up to 100 milliliters was used to determine the residue. Yogurt was used as a semi-solid and biscuits as a solid. The findings were recorded and examined according to the Dzeiwas endoscopic evaluation protocol to score the dysphagia levels of our patients between 1 and 6. Score 1 was considered “normal swallowing function”, while scores between 2 and 6 were considered “dysphagia” and were graded from minimal to severe ( 23 ). b) Swallowing Electrophysiology : The physical medicine and rehabilitation specialist performed the electrophysiological evaluation with a 10-channel EMG device by Medelec Synergy (Oxford, England). ( 24 , 25 ) The motor component and muscle of swallowing are evaluated with sEMG. In particular, sEMG provides the amplitude, peak and latency of muscle contraction, and magnitude and temporal parameters such as duration and frequency ( 26 , 27 ). During swallowing, the suprahyoid muscles between the mandible and the hyoid provide hyoid elevation, and these muscles have important roles in the pharyngeal phase of swallowing. ( 26 , 28 ). The patients were made to sit with their heads in a neutral position. An active disk electrode was placed on the submental muscles, a reference disk electrode was placed on the chin, and a laryngeal (piezoelectric) sensor was placed in the coniotomy area and fixed. The signals were recorded with a filtered (band-pass 0.01-20 Hz) channel. The first of the two deviations obtained with the piezoelectric sensor indicated the elevation of the larynx, and the second indicated the end of the pharyngeal reflex phase. The beginning of the first deviation is called ‘0’, while the beginning of the second deviation indicating the end of the pharyngeal reflex is called ‘2’. The 0–2 interval is the time elapsed during the elevation and floating of the larynx. In other words, the 0–2 interval is the time that triggers the swallowing reflex. The time between the point (A) that is the beginning of the SM-EMG and the first point (0) that the swallowing reflex begins. The ‘A-0’ time interval is the time between the voluntary contraction of the submental muscle complex and the triggering of the swallowing reflex, giving the oral phase duration. The A-C time interval is recorded as the total oropharyngeal swallowing time as the entire period during which SM muscle activity is present. c) Ultrasonographic (US) evaluation : Ultrasound is also used in the evaluation of swallowing ( 29 ). The evaluation includes grading the cross-sectional area, thickness, contractility, and echogenicity of the muscle ( 30 ). The oral and suprahyoid muscles can be easily identified using ultrasound, but these measurements can also be made during muscle movement and thus can be used to evaluate muscle function ( 31 ). All measurements were performed in the supine position. Real-time imaging and cross-sectional areas (CSAs) (geniohyoid and bilateral anterior digastric muscles) were performed with an ultrasound device (GE Logiq P5, General Electric, Korea) and a 7–12 MHz linear array transducer. The geniohyoid and anterior digastric muscles were measured with the patients in a relaxed position with the tongue in the mouth. The distance between the mandible bone and the hyoid bone was measured and the skin was marked one third behind the inferior border of the mandible. The transducer was placed in the coronal plane to measure the CSAs of the muscles. Study protocol All subjects were assessed for swallowing. Pre-treatment results in patient group and healthy group were compared. Evaluation parameters for patients were performed at 1 month after botulinum toxin administration. The patient group also compared pre- and post-treatment impairment levels. Statistical analysis Statistical analysis was performed using the Statistical Package for the Social Sciences 20.0 (SPSS, Inc.; Chicago, IL, USA) version for Windows. Normality of the continuous variables was assessed by the Kolmogorov Smirnov test. Descriptive statistics were shown as mean (standard deviation (SD)) for continuous variables and frequencies (%) for nominal variables. Statistically significant differences in repeated measurements within the groups were evaluated with the Wilcoxon and Friedman tests. The Mann-Whitney U were used for the significantly differences between groups. The results were considered as significant for p < 0.05. RESULTS While 5 of the 16 (31.3%) patients were female, 11 (68.7%)were male and the mean age was 45.12 ± 7.28 years of study subjects (n = 16). Distribution and comparison of demographic characteristics of subjects according to the groups are presented in Table 1. The disease duration of the patients was 2.74 (SD 1.26) years. None of the subjects had dysphagia according to fiberoptic endoscopic evaluation. Comparison of electrophysiological and ultrasonographic pre- and post-treatment evaluation results of groups are shown in Tables 2 and 3. Electrophysiologically, while the swallowing triggering reflex time (0–2) and total swallow durations (A-C) of patients were more longer than healthy (p 0.05). Moreover, geniohyoid muscle area was larger than healthy group (p = 0.023). It was seen that the swallowing triggering reflex time ant total swallow durations of patients were similar to healthy in the control of the first month after Botulinum toxin application. After treatment, all patients were satisfied (n = 8, 100%). Moreover, 5 patients (62.5%) they said that it was especially easy to eat solid foods than before. Also, none of the patients had any aspiration findings. DISCUSSION Botox injection in spasmodic dysphonia was first performed by Blitzer et al in 1984 ( 36 ). Dysphagia may be observed after BTX injection and its frequency is between 10–90% ( 15 , 37 , 38 ) and this side effect can be reduced by performing BTX injection with EMG and ultrasound guidance ( 38 ). In some studies, dysphagia side effect was compared before and after treatment ( 16 , 17 , 18 ). Changes in swallowing, such as the presence of food in the epiglottic vallecula due to delayed swallowing reflex, have been described as changes in the pharyngeal phase of swallowing in these patients before treatment ( 39 – 41 ). In our study, this was not detected in the swallowing evaluation and patients without dysphagia were included in this study to show whether Botox has side effects. In the literature, dysphagia can be seen in patients with cervical dystonia before and after botox or surgery. This dysphagia has been explained by two different mechanisms. One of these mechanisms is the abnormal position of the neck, which causes anatomical asymmetry in swallowing in cervical dystonia. ( 42 – 45 ) However, this interpretation does not explain dysphagia in spasmodic dystonias without abnormal neck movements and in some oromandibular dystonias. The second possibility is neurogenic dysfunction, which causes delayed swallowing and other oropharyngeal findings.( 42 – 45 ) Since our patient group consists of patients with adductor type spasmadic dysphonia, there is no anatomical asymmetry. Fiberoptic endoscopic swallowing evaluation (FEES) described by Dr. Langmore ( 46 ) is the gold standard for swallowing evaluation. FEES and videofluoroscopic swallowing evaluation are very important methods used in the diagnosis of oropharyngeal dysphagia (OD) ( 22 ). In our study, all patients were evaluated with FEES before and after Botox injection, and no dysphagia findings were found before or after. However, a multidisciplinary approach is very important for the evaluation of dysphagia, including not only FEES but also videofluoroscopic swallowing evaluation, EMG and ultrasound. Some studies have examined the utility of sEMG of the submental muscles in swallowing rehabilitation. In particular, sEMG has been used to assess swallowing and to examine hyolaryngeal elevation, pre- and post-swallow muscle contraction, and its duration.( 47 – 50 ) Surface electromyography (sEMG) is a valid and reliable method for examining swallowing and determining normal swallowing ( 51 ). SEMG is a noninvasive tool for assessing specific aspects of the complex muscle activity involved in swallowing. SEMG is simple and reliable to perform.( 52 , 53 ) It records electrical activity from the anterior digastric muscle and suprahyoid area muscles (i.e., geniohyoid and mylohyoid muscles) ( 54 ) The most important for swallowing are SEMG findings showing hyoid elevation in the anterior compartment and contraction of the submental muscles ( 49 ). In the literature, swallowing time varies between 0.80 and 1.60 seconds ( 55 , 56 ). This time does not change from age 12 to age 70. After this age, swallowing time increases significantly ( 51 , 52 , 57 , 58 ). In the study by C. Ertekin et al., prolonged SM muscle complex activity during swallowing (68%) was observed. Prolonged laryngeal displacement was seen in 42% of patients with cervical dystonia and decreased SM muscle activity in 31%. These two findings are also seen in Parkinson's. ( 17 ) In our study, before Botox, patients' swallowing reflex time (0–2) and total swallowing time (A-C) were longer than healthy individuals (p 0.05). In the first month after botulinum toxin injection, it was seen that patients' swallowing reflex time and total swallowing time were similar to healthy individuals. All patients were satisfied after treatment (n = 8, 100%). In addition, 5 patients (62.5%) said that eating solid foods was easier than before. In addition, none of the patients had any signs of aspiration. In this study, the selection of patients with spasmodic dysphonia without dysphagia affects the results. Coordinated contraction of the suprahyoid muscle (shM) complex, which includes the digastric, mylohyoid, and geniohyoid muscles, causes displacement of the hyoid bone and promotes bolus propulsion into the esophagus. Most studies have evaluated the thickness, cross-sectional area, and echo density of the tongue or other swallowing muscles(digastric, geniohyoid and mylohyoid) when evaluating dysphagia with ultrasound. ( 59 – 62 ) During swallowing, the suprahyoid muscle contracts and a change in thickness and upward movement occurs. The severity of dysphagia depends on the difference in the displacement of these muscles. and plays an important role in the pharyngeal phase of swallowing. ( 63 , 64 , 65 ). In some studies, the suprahyoid muscle complex and displacement of patients with stroke, ALS, MG ( 64 – 70 ) and inflammatory myopathy, whose dysphagia was evaluated with VFSS, were evaluated with ultrasound and it was seen that the findings indicating the severity of dysphagia were correlated. ( 71 ) In our study, there was no significant difference between the healthy group and patients with spasmodic dysphonia in ultrasonographic evaluation, the geniohyoid muscle was observed to be larger in patients with spasmodic dysphonia than in the healthy group, but this was not significant for us. Dysphagia may be seen in patients with spasmodic dysphonia due to muscle involvement, some studies have shown that this complaint may occur secondary to botox injection, which is the gold standard in treatment, our patient group consisted of patients without dysphagia and no dysphagia was observed after botox. CONCLUSION Even if they do not describe symptoms of swallowing dysfunction, their swallowing function may be affected by laryngeal dystonia compared to healthy people. Our patient group did not complain of dysphagia. FEES, EMG, and ultrasound evaluation revealed no findings related to swallowing dysfunction. In addition, no change was observed in swallowing functions after botulinum toxin injection. Declarations This study was conducted at Dışkapı Yıldırım Beyazıt Training and Research Hospital, Department of Otorhinolaryngology, and Dışkapı Yıldırım Beyazıt Training and Research Hospital,Department of Physical Therapy and Rehabilitation Source of financial support or funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflict of interest statement: All authors declare that they have no conflicts of interest. Corresponding author Esma Altan Adress: Ministry of Health Etlik City Hospital, Department of Otorhinolaryngology- Head and Neck Surgery, Ankara, Turkey E-mail adress: [email protected] Post code: 06170 Telephone: +90 797 00 00 Mobil phone number: +90 0505 309 09 08 Acknowledgement: None References Hintze JM, Ludlow CL, Bansberg SF, Adler CH, Lott DG (2017) Spasmodic dysphonia: a review. Part 1: pathogenic factors. 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Dysphagia 32(1):115–122. https://doi.org/10.1007/s00455-016-9749-z Crary MA, Carnaby GD, Groher ME (eds) (2006) Biomechanical correlates of surface electromyography signals obtained during swallowing by healthy adults. Journal of Speech, Language, and Hearing Research, 49(1), 186–193. https://doi.org/10.1044/1092-4388(2006/015 ) Ding R, Larson CR, Logemann JA, Rademaker AW (2002) Surface electromyographic and electroglottographic studies in normal subjects under two swallow conditions: Normal and during the Mendelsohn manuever. Dysphagia 17(1):1–12. https://doi.org/10.1007/s00455-001-0095-3 Crary MA, Carnaby Mann GD, Groher ME (2007) Identification of swallowing events from sEMG signals obtained from healthy adults. Dysphagia 22(2):94–99 Vaiman M, Eviatar E, Segal S (2004) Evaluation of normal deglutitionwith the help of rectified surface electromyography records. Dysphagia 19(2):125–132 Vaiman M, Eviatar E, Segal S (2004) Surface electromyography studies of swallowing in normal subjects: a review of 440 adults. Report 2. Quantitative data: amplitude measures. Otolaryngol Head Neck Surg 131(5):773–780 Widmalm SE, Lillie JH, Ash MM (1988) Anatomical and electromyographic studies of the digastric muscles. J Oral Rehab 15(1):3–21 Wilson EM, Green JR (2006) Coordinative organization of lingual propulsion during the normal adult swallow. Dysphagia 21(4):226–236 Moriniere S, Beutter P, Boiron M (2006) Sound component duration of healthy human pharyngoesophageal swallowing: a gender comparison study. Dysphagia 21(3):175–182 Vaiman M, Eviatar E, Segal S (2004) Surface electromyographic studies of swallowing in normal subjects: a review of 440 adults. Report 3. Qualitative data. Otolaryngol Head Neck Surg 131(6):977–985 Vaiman M, Segal S, Eviatar E (2004) Surface electromyographic studies of swallowing in normal children, age 4–12 years. Int J Pediatr Otorhinolaryngol 68(1):65–73 Nakamori M, hosomi N, takaki M, hiraoka, yoshikawa a et al (2016) M, tongue thickness evaluation using ultrasonography can predict swallowing function in amyotrophic lateral sclerosis patients. clin Neuro physiol. ;127:1669–74 Kajisa E, tohara h, Nakane a, Wakasugi y, hara K, yamaguchi K et al (2018) the relationship between jaw-opening force and the cross-sec tional area of the suprahyoid muscles in healthy elderly. J oral rehabil. ;45:222–7 Ogawa N, Mori t, fujishima i, Wakabayashi h, itoda M, Kunieda K et al (2018) ultrasonography to measure swallowing muscle mass and qual ity in older patients with sarcopenic dysphagia. J am Med dir assoc. ;19:516–22 Chantaramanee a, Nakagawa tohara, hara K et al (2019) K, Nakane a, yama guchi K, association between echo intensity of the tongue and its thickness and function in elderly subjects. J oral rehabil. ;46:634–9 Hara K (2018) tohara h, Minakuchi s. treatment and evaluation of dys phagia rehabilitation especially on suprahyoid muscles as jaw-opening muscles. Jpn dent sci rev 54:151–159 Lee W (2021) lim Mh, seo hG, oh bM, Kim s. hyoid kinematic fea tures for poor swallowing prognosis in patients with post-stroke dyspha gia. sci rep 11:1471 Saconato M (2020) leite fc, lederman hM, chiari bM, Gonçalves Mi. temporal and sequential analysis of the pharyngeal phase of swallowing in poststroke patients. Dysphagia 35:598–615 Seo, hG (2016) oh bM, han tr. swallowing kinematics and factors as sociated with laryngeal penetration and aspiration in stroke survivors with dysphagia. Dysphagia 31:160–168 May Nh, pisegna JM (2017) Marchina s, langmore sE, Kumar s, pear son WG Jr. pharyngeal swallowing mechanics secondary to hemispheric stroke. J stroke cerebrovasc dis 26:952–961 Garand, Kl (2018) schwertner r, chen a, pearson WG Jr. computational analysis of pharyngeal swallowing mechanics in patients with motor neu ron disease: a pilot investigation. dysphagia ;33:243–50 Park yc et al (2022) lee Jy, lee Js, park Js, oh KW, Kim sh, charac teristics of dysphagia based on the type of als in Korean patients evalu ated using videofluoroscopic study: A retrospective analysis. Dysphagia. ;37:1748–56 Higo R, Nito T, Tayama N (2005) Videofluoroscopic assessment of swal lowing function in patients with myasthenia gravis. J Neurol sci 231:45–48 Langdon pc, Mulcahy K (2012) shepherd Kl, low Vh, Mastaglia fl. Pharyngeal dysphagia in inflammatory muscle diseases resulting from im paired suprahyoid musculature. Dysphagia 27:408–417 Additional Declarations The authors declare no competing interests. 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According to the muscles involved, there are forms of SD: adductor, abductor and mixed. Adductor SD (ADSD) is characterized by an effortful and strained voice as if choking by contracting the muscles that provide adduction and blocking the airflow. In abductor SD (ABSD), the cords due to abduction do not close during phonation and are associated with dyspnea and aphonia (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). ADSD is the most common type in the clinic, mixed type is less common and it is difficult to diagnose (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTreatment of SD; involves the injection of botulinum toxin (BT) into the thyroarytenoid muscle in the adductor type and the posterior cricoarytenoid muscle in the abductor type, sometimes under electomyography guidance, and sometimes surgical procedures and voice therapy. Botox injection is the gold standard. Botox prevents muscle contractions by binding to acetylcholine receptors at the neuromuscular junction and inhibiting its release. Surgical techniques include type 2 thyroplasty (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e), myectomy (thyroarytenoid muscle) (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) and selective laryngeal denervation-reinnervation (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). These surgical treatments are used in the adductor type. Voice therapy is a part of the treatment but its effectiveness is limited, therapy can be used together with other treatments.\u003c/p\u003e \u003cp\u003eSwallowing has some phases; it is a complex behavior that takes place with the work of oral, pharyngeal, and esophageal muscles (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Dysphagia can be defined as the difficulty encountered by the food that starts with chewing in the mouth and goes all the way to the stomach. Oral dysphagia can be defined as any difficulty in the preparation of a bolus. Pharyngeal dysphagia may be caused by absence or delay in swallowing reflex and esophageal dysphagia may be caused by esophageal or sphincter disorder (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eDysphagia can also occur due to Botox, usually after treatment for spasmodic dystonia (botulinum toxin injection).It is defined as one of the most common side effects after botox injection in cervical dystonias and spasmodic dysphonias and the incidence rate is between 10\u0026ndash;90% (\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e) and injections using USG and EMG can reduce these side effects (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Very few studies have evaluated swallowing before and after treatment (\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). Many studies have not focused much on dysphagia secondary to Botox. (\u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e) Especially, involuntary pharyngeal phase of swallowing is affected and premature leak is seen with fluids. This condition, which can be treated with diet modifications, is often overlooked because it is transient.\u003c/p\u003e \u003cp\u003eThere is no study to evaluate as multimodal and objective of the effect of botulinum toxin on swallowing function in these patients. Therefore, we aimed to evaluate swallowing functions of patients with spasmodic dystonia without dysphagia symptom and to investigate the effect of botulinum toxin treatment on swallowing function.\u003c/p\u003e"},{"header":"MATERIAL AND METHOD","content":"\u003cp\u003eThe Clinical Research Ethics Committee (Date:October 2023, Decision No:597) approved before the research began. We obtained informed consent from all participants.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eParticipants\u003c/h2\u003e\n \u003cp\u003eA total of 16 subjects consisting of 8 patients with spasmodic dysphonia and without dysphagia symptoms, who were planned to undergo botulinum toxin injection into their thyroaritenoid muscles and 8 healthy volunteers with age and gender matched these patients were included in the study.\u003c/p\u003e\n \u003cp\u003eSubjects who had any metabolic/endocrine and progressive central or peripheral nervous system diseases and had past surgical history or using drug that can cause cause swallowing dysfunction were excluded from the study. In addition, patients with multifocal or segmental dystonia and who described difficulty in swallowing were excluded from the study.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eBotulinum Toxin Injection\u003c/h3\u003e\n\u003cp\u003eIn spasmodic dysphonia, involuntary closure of the vocal cords causes speech difficulties. The gold standard treatment for these patients is periodic injections of botulinum toxin A (BTX-A) into these muscles to prevent them from contracting involuntarily. In the adductor type, the improvement in voice after Botox is 8.0\u0026ndash;15.1 weeks. (\u003cspan class=\"CitationRef\"\u003e32\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e) Commonly reported side effects of BTX-A injections include a slightly breathy voice (25\u0026ndash;35% of patients) and cough or dysphagia, especially with liquids (10% of patients). The dose and timing of the patient\u0026apos;s next injection is determined by the patient\u0026apos;s side effects .(\u003cspan class=\"CitationRef\"\u003e35\u003c/span\u003e)\u003c/p\u003e\n\u003cp\u003eIn our study patients with adductor type spasmodic dysphonia were injected with 2.5 units of onabotulinum toxin Type A (Botox\u0026reg;) botulinum toxin into both thyroarytenoid muscles with EMG guidance\u003c/p\u003e\n\u003cp\u003eAfter treatment, patients\u0026apos; satisfaction was questioned by Likert scale as \u0026ldquo;I am satisfied\u0026rdquo;, \u0026ldquo;I am not satisfied\u0026rdquo; and \u0026ldquo;I am not satisfied nor satisfied\u0026rdquo;.\u003c/p\u003e\n\u003ch3\u003eAssessment Tools\u003c/h3\u003e\n\u003cp\u003eFirst, demographic and disease characteristics were obtained from all participants. Then, fiberoptic endoscopic evaluation, swallowing electrophysiology and ultrasonographic evaluation were performed to evaluate swallowing functions.\u003c/p\u003e\n\u003cp\u003eDemographic and disease characteristics: Patients and volunteers, including age, gender and educational status, as well as dystonia duration of patients were recorded.\u003c/p\u003e\n\u003cp\u003eSwallowing evaluation: The following three assessment methods were used to evaluate the swallowing functions of the participants.\u003c/p\u003e\n\u003col style=\"list-style-type: lower-alpha;\"\u003e\n \u003cli\u003e\n \u003cp\u003eFiberoptic Endoscopic Evaluation\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eSwallowing Electrophysiology\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eUltrasonographic Evaluation\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003e\u003cstrong\u003ea) Flexible Fiberoptic Endoscopic Evaluation of Swallowing (FEES\u003c/strong\u003e): The most important and gold standard diagnostic methods for the diagnosis of dysphagia (OD) are FEES and videofluoroscopic swallowing study (VFSS). (\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e). The advantages of FEES are that it can be performed in any environment including the patient\u0026apos;s bedside, it has no radiation effect, and its disadvantages are that the passage cannot be seen clearly when the pharynx is closed during swallowing (\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e). Endoscopic evaluation of the patients was performed by the same specialist, with the patient in a sitting position, using a 3.4 mm diameter channelless fiberoptic nasopharyngoscope, light source, camera, monitor and DVD recorder (KarlStorz GmbH \u0026amp; Co KG, Tuttlingen, Germany). Local anesthetics were not used during this test. Water aspiration or penetration up to 100 milliliters was used to determine the residue. Yogurt was used as a semi-solid and biscuits as a solid. The findings were recorded and examined according to the Dzeiwas endoscopic evaluation protocol to score the dysphagia levels of our patients between 1 and 6. Score 1 was considered \u0026ldquo;normal swallowing function\u0026rdquo;, while scores between 2 and 6 were considered \u0026ldquo;dysphagia\u0026rdquo; and were graded from minimal to severe (\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eb) Swallowing Electrophysiology\u003c/strong\u003e: The physical medicine and rehabilitation specialist performed the electrophysiological evaluation with a 10-channel EMG device by Medelec Synergy (Oxford, England). (\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e) The motor component and muscle of swallowing are evaluated with sEMG. In particular, sEMG provides the amplitude, peak and latency of muscle contraction, and magnitude and temporal parameters such as duration and frequency (\u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e). During swallowing, the suprahyoid muscles between the mandible and the hyoid provide hyoid elevation, and these muscles have important roles in the pharyngeal phase of swallowing. (\u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e). The patients were made to sit with their heads in a neutral position. An active disk electrode was placed on the submental muscles, a reference disk electrode was placed on the chin, and a laryngeal (piezoelectric) sensor was placed in the coniotomy area and fixed. The signals were recorded with a filtered (band-pass 0.01-20 Hz) channel. The first of the two deviations obtained with the piezoelectric sensor indicated the elevation of the larynx, and the second indicated the end of the pharyngeal reflex phase. The beginning of the first deviation is called \u0026lsquo;0\u0026rsquo;, while the beginning of the second deviation indicating the end of the pharyngeal reflex is called \u0026lsquo;2\u0026rsquo;. The 0\u0026ndash;2 interval is the time elapsed during the elevation and floating of the larynx. In other words, the 0\u0026ndash;2 interval is the time that triggers the swallowing reflex. The time between the point (A) that is the beginning of the SM-EMG and the first point (0) that the swallowing reflex begins. The \u0026lsquo;A-0\u0026rsquo; time interval is the time between the voluntary contraction of the submental muscle complex and the triggering of the swallowing reflex, giving the oral phase duration. The A-C time interval is recorded as the total oropharyngeal swallowing time as the entire period during which SM muscle activity is present.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ec) Ultrasonographic (US) evaluation\u003c/strong\u003e: Ultrasound is also used in the evaluation of swallowing (\u003cspan class=\"CitationRef\"\u003e29\u003c/span\u003e). The evaluation includes grading the cross-sectional area, thickness, contractility, and echogenicity of the muscle (\u003cspan class=\"CitationRef\"\u003e30\u003c/span\u003e). The oral and suprahyoid muscles can be easily identified using ultrasound, but these measurements can also be made during muscle movement and thus can be used to evaluate muscle function (\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eAll measurements were performed in the supine position. Real-time imaging and cross-sectional areas (CSAs) (geniohyoid and bilateral anterior digastric muscles) were performed with an ultrasound device (GE Logiq P5, General Electric, Korea) and a 7\u0026ndash;12 MHz linear array transducer. The geniohyoid and anterior digastric muscles were measured with the patients in a relaxed position with the tongue in the mouth. The distance between the mandible bone and the hyoid bone was measured and the skin was marked one third behind the inferior border of the mandible. The transducer was placed in the coronal plane to measure the CSAs of the muscles.\u003c/p\u003e\n\u003ch3\u003eStudy protocol\u003c/h3\u003e\n\u003cp\u003eAll subjects were assessed for swallowing. Pre-treatment results in patient group and healthy group were compared. Evaluation parameters for patients were performed at 1 month after botulinum toxin administration. The patient group also compared pre- and post-treatment impairment levels.\u003c/p\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003eStatistical analysis\u003c/h2\u003e\n \u003cp\u003eStatistical analysis was performed using the Statistical Package for the Social Sciences 20.0 (SPSS, Inc.; Chicago, IL, USA) version for Windows. Normality of the continuous variables was assessed by the Kolmogorov Smirnov test. Descriptive statistics were shown as mean (standard deviation (SD)) for continuous variables and frequencies (%) for nominal variables. Statistically significant differences in repeated measurements within the groups were evaluated with the Wilcoxon and Friedman tests. The Mann-Whitney U were used for the significantly differences between groups. The results were considered as significant for p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eWhile 5 of the 16 (31.3%) patients were female, 11 (68.7%)were male and the mean age was 45.12\u0026thinsp;\u0026plusmn;\u0026thinsp;7.28 years of study subjects (n\u0026thinsp;=\u0026thinsp;16). Distribution and comparison of demographic characteristics of subjects according to the groups are presented in Table\u0026nbsp;1.\u003c/p\u003e \u003cp\u003eThe disease duration of the patients was 2.74 (SD 1.26) years. None of the subjects had dysphagia according to fiberoptic endoscopic evaluation. Comparison of electrophysiological and ultrasonographic pre- and post-treatment evaluation results of groups are shown in Tables\u0026nbsp;2 and 3.\u003c/p\u003e \u003cp\u003eElectrophysiologically, while the swallowing triggering reflex time (0\u0026ndash;2) and total swallow durations (A-C) of patients were more longer than healthy (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), oral phase time were similar (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Moreover, geniohyoid muscle area was larger than healthy group (p\u0026thinsp;=\u0026thinsp;0.023).\u003c/p\u003e \u003cp\u003eIt was seen that the swallowing triggering reflex time ant total swallow durations of patients were similar to healthy in the control of the first month after Botulinum toxin application. After treatment, all patients were satisfied (n\u0026thinsp;=\u0026thinsp;8, 100%). Moreover, 5 patients (62.5%) they said that it was especially easy to eat solid foods than before. Also, none of the patients had any aspiration findings.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eBotox injection in spasmodic dysphonia was first performed by Blitzer et al in 1984 (\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e). Dysphagia may be observed after BTX injection and its frequency is between 10\u0026ndash;90% (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e) and this side effect can be reduced by performing BTX injection with EMG and ultrasound guidance (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e). In some studies, dysphagia side effect was compared before and after treatment (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). Changes in swallowing, such as the presence of food in the epiglottic vallecula due to delayed swallowing reflex, have been described as changes in the pharyngeal phase of swallowing in these patients before treatment (\u003cspan additionalcitationids=\"CR40\" citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e). In our study, this was not detected in the swallowing evaluation and patients without dysphagia were included in this study to show whether Botox has side effects.\u003c/p\u003e \u003cp\u003eIn the literature, dysphagia can be seen in patients with cervical dystonia before and after botox or surgery. This dysphagia has been explained by two different mechanisms. One of these mechanisms is the abnormal position of the neck, which causes anatomical asymmetry in swallowing in cervical dystonia. (\u003cspan additionalcitationids=\"CR43 CR44\" citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e) However, this interpretation does not explain dysphagia in spasmodic dystonias without abnormal neck movements and in some oromandibular dystonias. The second possibility is neurogenic dysfunction, which causes delayed swallowing and other oropharyngeal findings.(\u003cspan additionalcitationids=\"CR43 CR44\" citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e) Since our patient group consists of patients with adductor type spasmadic dysphonia, there is no anatomical asymmetry.\u003c/p\u003e \u003cp\u003eFiberoptic endoscopic swallowing evaluation (FEES) described by Dr. Langmore (\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e) is the gold standard for swallowing evaluation. FEES and videofluoroscopic swallowing evaluation are very important methods used in the diagnosis of oropharyngeal dysphagia (OD) (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). In our study, all patients were evaluated with FEES before and after Botox injection, and no dysphagia findings were found before or after. However, a multidisciplinary approach is very important for the evaluation of dysphagia, including not only FEES but also videofluoroscopic swallowing evaluation, EMG and ultrasound.\u003c/p\u003e \u003cp\u003eSome studies have examined the utility of sEMG of the submental muscles in swallowing rehabilitation. In particular, sEMG has been used to assess swallowing and to examine hyolaryngeal elevation, pre- and post-swallow muscle contraction, and its duration.(\u003cspan additionalcitationids=\"CR48 CR49\" citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e) Surface electromyography (sEMG) is a valid and reliable method for examining swallowing and determining normal swallowing (\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e). SEMG is a noninvasive tool for assessing specific aspects of the complex muscle activity involved in swallowing. SEMG is simple and reliable to perform.(\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e, \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e) It records electrical activity from the anterior digastric muscle and suprahyoid area muscles (i.e., geniohyoid and mylohyoid muscles) (\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e) The most important for swallowing are SEMG findings showing hyoid elevation in the anterior compartment and contraction of the submental muscles (\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e). In the literature, swallowing time varies between 0.80 and 1.60 seconds (\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e, \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e). This time does not change from age 12 to age 70. After this age, swallowing time increases significantly (\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e, \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e, \u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e57\u003c/span\u003e, \u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e). In the study by C. Ertekin et al., prolonged SM muscle complex activity during swallowing (68%) was observed. Prolonged laryngeal displacement was seen in 42% of patients with cervical dystonia and decreased SM muscle activity in 31%. These two findings are also seen in Parkinson's. (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eIn our study, before Botox, patients' swallowing reflex time (0\u0026ndash;2) and total swallowing time (A-C) were longer than healthy individuals (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), while oral phase times were similar (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). In the first month after botulinum toxin injection, it was seen that patients' swallowing reflex time and total swallowing time were similar to healthy individuals. All patients were satisfied after treatment (n\u0026thinsp;=\u0026thinsp;8, 100%). In addition, 5 patients (62.5%) said that eating solid foods was easier than before. In addition, none of the patients had any signs of aspiration. In this study, the selection of patients with spasmodic dysphonia without dysphagia affects the results.\u003c/p\u003e \u003cp\u003eCoordinated contraction of the suprahyoid muscle (shM) complex, which includes the digastric, mylohyoid, and geniohyoid muscles, causes displacement of the hyoid bone and promotes bolus propulsion into the esophagus. Most studies have evaluated the thickness, cross-sectional area, and echo density of the tongue or other swallowing muscles(digastric, geniohyoid and mylohyoid) when evaluating dysphagia with ultrasound. (\u003cspan additionalcitationids=\"CR60 CR61\" citationid=\"CR59\" class=\"CitationRef\"\u003e59\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e62\u003c/span\u003e) During swallowing, the suprahyoid muscle contracts and a change in thickness and upward movement occurs. The severity of dysphagia depends on the difference in the displacement of these muscles. and plays an important role in the pharyngeal phase of swallowing. (\u003cspan citationid=\"CR63\" class=\"CitationRef\"\u003e63\u003c/span\u003e, \u003cspan citationid=\"CR64\" class=\"CitationRef\"\u003e64\u003c/span\u003e, \u003cspan citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e). In some studies, the suprahyoid muscle complex and displacement of patients with stroke, ALS, MG (\u003cspan additionalcitationids=\"CR65 CR66 CR67 CR68 CR69\" citationid=\"CR64\" class=\"CitationRef\"\u003e64\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR70\" class=\"CitationRef\"\u003e70\u003c/span\u003e) and inflammatory myopathy, whose dysphagia was evaluated with VFSS, were evaluated with ultrasound and it was seen that the findings indicating the severity of dysphagia were correlated. (\u003cspan citationid=\"CR71\" class=\"CitationRef\"\u003e71\u003c/span\u003e) In our study, there was no significant difference between the healthy group and patients with spasmodic dysphonia in ultrasonographic evaluation, the geniohyoid muscle was observed to be larger in patients with spasmodic dysphonia than in the healthy group, but this was not significant for us.\u003c/p\u003e \u003cp\u003eDysphagia may be seen in patients with spasmodic dysphonia due to muscle involvement, some studies have shown that this complaint may occur secondary to botox injection, which is the gold standard in treatment, our patient group consisted of patients without dysphagia and no dysphagia was observed after botox.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eEven if they do not describe symptoms of swallowing dysfunction, their swallowing function may be affected by laryngeal dystonia compared to healthy people. Our patient group did not complain of dysphagia. FEES, EMG, and ultrasound evaluation revealed no findings related to swallowing dysfunction. In addition, no change was observed in swallowing functions after botulinum toxin injection.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eThis study was conducted at Dışkapı Yıldırım Beyazıt Training and Research Hospital, Department of Otorhinolaryngology, and Dışkapı Yıldırım Beyazıt Training and Research Hospital,Department of Physical Therapy and Rehabilitation\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSource of financial support or funding:\u0026nbsp;\u003c/strong\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest statement:\u0026nbsp;\u003c/strong\u003eAll authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorresponding author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEsma Altan\u003c/p\u003e\n\u003cp\u003eAdress: Ministry of \u0026nbsp;Health Etlik City Hospital, Department of Otorhinolaryngology- Head and Neck Surgery, Ankara, Turkey\u003c/p\u003e\n\u003cp\u003eE-mail adress: [email protected]\u003c/p\u003e\n\u003cp\u003ePost code: 06170\u003c/p\u003e\n\u003cp\u003eTelephone: +90 797 00 00\u003c/p\u003e\n\u003cp\u003eMobil phone number: +90 0505 309 09 08 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgement:\u0026nbsp;\u003c/strong\u003eNone\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHintze JM, Ludlow CL, Bansberg SF, Adler CH, Lott DG (2017) Spasmodic dysphonia: a review. 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J stroke cerebrovasc dis 26:952\u0026ndash;961\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGarand, Kl (2018) schwertner r, chen a, pearson WG Jr. computational analysis of pharyngeal swallowing mechanics in patients with motor neu ron disease: a pilot investigation. dysphagia ;33:243\u0026ndash;50\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePark yc et al (2022) lee Jy, lee Js, park Js, oh KW, Kim sh, charac teristics of dysphagia based on the type of als in Korean patients evalu ated using videofluoroscopic study: A retrospective analysis. Dysphagia. ;37:1748\u0026ndash;56\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHigo R, Nito T, Tayama N (2005) Videofluoroscopic assessment of swal lowing function in patients with myasthenia gravis. J Neurol sci 231:45\u0026ndash;48\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLangdon pc, Mulcahy K (2012) shepherd Kl, low Vh, Mastaglia fl. Pharyngeal dysphagia in inflammatory muscle diseases resulting from im paired suprahyoid musculature. Dysphagia 27:408\u0026ndash;417\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Swallowing, Dysphagia, Voice, Dysphonia, Laryngeal Dystonia, Tremor","lastPublishedDoi":"10.21203/rs.3.rs-5967904/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5967904/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjectives:\u003c/strong\u003e Spasmodic dysphonia (SD) is a neurological movement disorder involving the laryngeal muscles. There are three main types: adductor, abductor and mixed type. adductor type is the most common and mixed type is the rarest.\u003cstrong\u003e \u003c/strong\u003eBotox is the gold standard in treatment, botox is applied to the affected muscle group according to the type of spasmodic dysphonia. Dysphagia often occurs as a side effect of treatment (botulinum toxin injection) in spasmodic dystonia. Sometimes dysphagia may be seen secondary to spasmodic dysphonia.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This study included 8 patients with adductor spasmodic dysphonia and 8 without dysphagia and 8 healthy subjects. Swallowing evaluation of both groups was performed by FEES, EMG and ultrasound.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003eSwallowing functions of patients with adductor spasmodic dysphonia were re-evaluated after botox injection into the thyroarytenoid muscle. No significant difference was observed in both groups\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e \u0026nbsp;In our study, our patient group consisted of patients with spasmodic dysphonia without dysphagia and dysphagia was not observed in patients evaluated with FEES, EMG and ultrasound after Botox.\u003c/p\u003e","manuscriptTitle":"Do we cause dysphagia when treating spasmodic dysphonia with botox?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-02-07 09:53:56","doi":"10.21203/rs.3.rs-5967904/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"65f60d3c-7b83-41bf-9ac5-99edf3350d5a","owner":[],"postedDate":"February 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":43901882,"name":"Otorhinolaryngology"}],"tags":[],"updatedAt":"2025-02-07T09:53:56+00:00","versionOfRecord":[],"versionCreatedAt":"2025-02-07 09:53:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5967904","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5967904","identity":"rs-5967904","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}