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Treatment of relapsing functional and organic dysphonia: a narrative literature review
Abstract
Information about failure and relapses is critical in deciding whether and how to treat a given condition, as well as during patient counselling before therapy. This paper aims to perform a non-systematic review of relapses and failure of dysphonia treatment in the adult population. Studies on failure and relapses after treatment of benign vocal fold lesions, functional dysphonia and neurogenic dysphonia were analysed. The frequency and the duration of follow-up were heterogeneous, and the management of relapses was reported in only a portion of the studies. Relapses after surgical treatment of benign vocal fold lesions ranged between 1% and 58% of cases, and their management was mainly surgical. Rates of relapse after voice therapy for functional dysphonia and spasmodic dysphonia were 12%- 88% and 8%-63%, respectively. Rates of relapse after surgical treatment for unilateral and bilateral vocal fold paralysis were 10%-39% and 6%-25%, respectively; treatment was mainly represented by surgical revision. In conclusion, failure and relapses of functional and organic dysphonias after therapy are not rare, but treatment modalities are seldomly reported. The data from this non-systematic review stresses the need for further research in this area.
Introduction
Dysphonia is a symptom due to an impairment of voice production and characterised by the alteration of voice quality or by vocal effort that impairs communication and affects quality of life. It has a life-time prevalence of 29.9% and a point-prevalence of 6.6%. It impacts working activities as 7.2% of employed adults were absent from work 1 or more days in the past year because of their voice, and 2% had more than 4 days of voice-related absence 1. In clinical practice, dysphonia accounts for up to 0.26% and 3.2% of visits for general practitioners and otorhinolaryngologists, respectively 2. Several conditions may lead to dysphonia, and they can be grouped in three major categories of voice disorders based on pathophysiology, auditory-perceptual and visual-perceptual observations: organic, functional and neurogenic dysphonias. Organic dysphonias are due to pathologies of laryngeal structures (vocal folds and laryngeal cartilages) and are usually subdivided into diseases of the vocal fold epithelium (papillomatosis, dysplasia, carcinoma), diseases of Reinke’s space (polyps, nodules, cysts, Reinke’s oedema), and impairments of the laryngeal cartilages (as after partial laryngectomy). Functional dysphonias include impairments in voice production without a laryngeal pathology due to a dysfunction of voice behaviour and include muscle tension dysphonia and psychogenic dysphonia. Neurogenic dysphonias are due to impairment of laryngeal movements because of diseases affecting either the peripheric (vagal or recurrent laryngeal nerve impairment) or central nervous system (such as spasmodic dysphonia or tremor). Organic, functional and neurogenic dysphonia represent 18.8%, 43.7% and 37.3% of the Italian population seeking treatment for dysphonia, respectively; multidimensional voice analysis showed that neurogenic dysphonia generally presents more severe voice impairment compared to organic and functional dysphonia 3. An additional condition often encountered in otorhinolaryngological clinical practice with potential effects on voice is Laryngo-pharyngeal Reflux Disease (LPRD).
Different treatments are now available for dysphonia including pharmacological (steroids, anti-reflux medicaments, botulinum toxin injection), surgical (microsurgical removal of laryngeal lesions, laryngeal framework surgery, filler injection) and behavioural therapy (voice therapy) 4,5. While several studies aimed to analyse the safety and efficacy of the available treatments, little is known about failure and relapses. Relapses consist in the return of a disease or its signs and symptoms after a period of improvement, while failure is defined as the lack of success or the inability to meet an expectation. Information about failures and relapses is critical in deciding whether and how to treat a given condition, and it is crucial during patient counselling before therapy. In particular, clear patient information about failure and relapses will avoid inappropriate discussions and requests, including legal issues, after treatment. The aim of this paper is to perform a non-systematic review of the frequency of relapses and failure of dysphonia treatment in the adult population.
Failure and relapses of benign organic dysphonia
Benign organic dysphonias are generally treated with surgery, with the only exception of vocal fold nodules. Although there is general consensus that benign vocal fold lesions should be treated surgically, voice therapy may play a role as an alternative treatment 4,5, or as an adjunctive therapy before or after therapy. However, the role of voice therapy is controversial and poorly investigated 6-8. Nonetheless, when analysing failures and relapses of surgical treatment, the potential impact of voice therapy as a complementary treatment should also be considered. In Table I studies on relapses and their treatment after surgery for vocal fold polyps, cysts, Reinke’s oedema and nodules are reported 9-29. The 9 studies considered in this review on surgical treatment for vocal fold polyps included more than 1000 patients, with a follow-up raging from 0 to 24 months and relapses ranging from 1% to 5%; post-surgical voice-therapy was reported in the majority of studies (7/9), while treatment of relapses was reported in only three studies, being surgical in all cases. The 6 studies considered in this review on surgical treatment for vocal fold cysts included less than 1000 patients, with a follow-up of 0-54 months and relapses ranging from 2% to 5%; post-surgical voice-therapy was reported in more than half of studies (7/9), while only one study reported the treatment of relapses, being surgical. The 5 studies considered in this review on surgical treatment for Reinke’s oedema included over 600 patients, with a follow-up raging from 0 months to 8 years and relapses ranging from 2% to 58%; post-surgical voice-therapy was reported in 3 of 5 studies, while treatment of relapses (surgical) was reported only in one study.
With regards to the management of vocal fold nodules, several areas of uncertainty remain, including poorly defined nomenclature, the natural history of paediatric vocal nodules, the establishment of criteria to measure successful treatment, optimal configuration of speech therapy regimens and the rationale for surgical intervention; nonetheless, there is general consensus that vocal fold nodules should be treated primarily through voice therapy. A recent systematic search on the effectiveness of voice therapy in adult patients with vocal fold nodules retrieved 9 papers 30. Although the study design and the evidence levels were low, all studies reported positive effects of voice therapy on different vocal parameters (perceptual, acoustic and self-assessment scores), but no data regarding the number of failures was reported. Data on the time interval between end of treatment and vocal fold nodules reduction or resolution was not available. Only in the study by Chernobelsky 28, conducted on 28 patients who underwent voice therapy, some information on relapses and failures was available; over a 10-year period, relapses were 22/28 (78%) and failures were 6/28 (21%). The 5 studies considered in this review on surgical treatment for vocal fold nodules included overall over 300 patients, with a follow-up ranging from 5 months to 15 years and relapses ranging from 3% to 33%; post-surgical voice-therapy was reported in 4 of 5 studies, while only one study reported the treatment of relapses, being surgical.
Failure and relapses of functional dysphonia
Functional dysphonias are generally treated through voice therapy. Although there is now evidence on the efficacy of voice therapy in this group of patients, little is known on relapses and failures. In Table II the studies on relapses and their treatment after voice therapy for muscle tension dysphonia and psychogenic dysphonia are reported 31-37. The 4 studies considered in this review on muscle tension dysphonia included less than 100 patients with failures ranging from 12% to 68%; data on failure and/or relapses management was not available 31-34. The 3 studies on psychogenic dysphonia included 81 patients with failures or relapses ranging from 50% to 88%; data on failure and/or relapses management were available in 2 of the 3 studies and always included the involvement of a psychologist 35-37.
Failure and relapses of neurogenic dysphonia
Unilateral vocal fold paralysis
Different treatments are now available for unilateral vocal fold paralysis (UVFP) including voice therapy, laryngeal injection with a variety of fillers, laryngeal framework surgery and laryngeal re-innervation; however, no consensus exists on which is the most effective treatment, or on the selection and timing for surgical or behavioural therapy. A recent systematic review analysed several studies on the efficacy of voice therapy for UVFP, showing a general improvement in voice, which is maintained for up to 1-year 38. However, no data on failure or relapses was reported. Only one study analysed the need for surgery after voice therapy: over 60% of the patients who underwent voice therapy for UVFP were satisfied with the results and did not require any additional treatment 39. In Table III the studies on failures and relapses and their treatment after surgery for UVFP are reported 40-51. Two studies conducted on almost 140 patients, investigating the efficacy of injection laryngoplasty with a follow-up up to 36 months, reported relapses in 10%-35% of cases; voice therapy was prescribed for all patients with relapses who underwent additional surgery, being reinjections in most cases. Eight studies on a total of over 1000 patients who underwent laryngeal framework surgery, with a follow-up range of 1-132 months, reported relapses in 10%-18% of cases; data on voice therapy after surgery was not available, but all patients with relapses underwent revision laryngeal framework surgery with a variety of surgical techniques. Finally, two studies analysed failure and relapses after laryngeal re-innervation; patients undergoing this surgery are still limited, and failures could be managed with either laryngeal framework surgery or laryngeal injection.
Bilateral vocal fold paralysis
Laryngeal dyspnoea due to bilateral vocal fold paralysis can be managed through a variety of surgical techniques, aiming to maintain oral respiration and limiting the impact on voice production. In Table IV the studies regarding failures and relapses and their treatment after surgery for bilateral vocal fold paralysis are reported 52-74. In the 23 studies on almost 580 patients who underwent surgery, with a follow-up up of 3-60 months, relapses were reported in 6%-25% of cases; voice therapy was not prescribed in any of the studies; treatment of relapses was reported in 8 of 23 studies, and in 7 of them it was revision surgery.
Spasmodic dysphonia
There is general agreement that voice therapy can not significantly improve any voice parameter in patients with spasmodic dysphonia. Several other effective treatments are currently available, including botulinum toxin injection and a range of surgical approaches, such as thyroarytenoid myoneurectomy, thyroplasty type II (without or with a titanium bridge), selective laryngeal adductor denervation-reinnervation and laryngeal nerve resection. Botulinum injection is the most widely applied treatment by both otorhinolaryngologists and neurologists, but should be repeated approximately every 3-4 months. Surgical approaches are more invasive, but have the potential to achieve stabilisation of the disease. In Table V several studies are reported, describing failures and relapses after treatment for spasmodic dysphonia and their management 75-90. In the 6 studies on 270 patients who underwent botulinum toxin injection, with a follow-up up ranging from 3 months to 7 years, failures were reported in 8%-35% of cases, reaching a 80% failure rate in at least a single treatment; data on voice therapy in addition to surgery or for non-responding patients was not reported. No data on management of failures after botulinum toxin injection was reported. In the 10 studies on 393 patients who underwent surgical treatment, with a follow-up up ranging from 6 to 49 months, failures were reported in 3%-63% of cases; voice-therapy was prescribed in only one case. The management of failure was reported in 6 of 10 papers and included several options: surgical revision (in most cases), botulinum toxin injection and collagen injection.
Failure and relapses of laryngopharyngeal reflux
LPRD is an inflammatory clinical condition affecting the upper aero-digestive tract, causing several symptoms, including dysphonia. Treatment options mainly include diet and lifestyle modifications, associated with proton pump inhibitors (PPIs) and/or alginate or magaldrate. Less frequently prescribed medications include prokinetic agents, H2 receptor antagonists, or γ-aminobutyric acid derivatives. Surgery (e.g. fundoplication) represents a treatment option only in selected patients. Similar to Gastro-oesophageal Reflux Disease (GERD) patients, individuals suffering from LPRD may experience recurrences throughout life. Based on the clinical course of the disease, three main LPRD subtypes have been recently described: (a) acute LPRD (29.3%), in case of complete resolution of symptoms with no relapses during a 3-year follow-up; (b) recurrent LPRD (40.7%), in case of one or more recurrences followed by a full response to medical treatment or dietary modifications, even if temporary; (c) chronic LPRD (30.0%), in case of chronic clinical course with absent or partial response to medical therapy, or when patients rapidly relapse if therapy is discontinued, thus requiring long-term treatment regimens 91. With regards to recurrent LPRD, similar data were also found by Koufman and coworkers when analysing data from 225 GERD patients with extra-oesophageal symptoms 92. The authors highlighted a chronic-recurrent clinical course in 25% of patients, even if high doses of PPIs were prescribed. A more recent study conducted by Verhasselt et al. on 100 LPR patients during a 3-year follow-up demonstrated a chronic-recurrent clinical course in one-third of cases 93. Nevertheless, treatment regimens for recurrences were not described in detail.
The actual success of therapies remains hard to predict. However, many risk factors have been identified to date as potential markers of treatment failure, in terms of both absent or incomplete response and increased risk of recurrence. The most important ones include: hiatal hernia; prolonged contact between the mucosa and the acid refluxate demonstrated through Hypopharyngeal-Oesophageal Multichannel Intraluminal Impedance-pH Monitoring (HEMII-pH) 94; celiac disease; proximal oesophageal dysmotility; achalasia; oesophageal spasms; gastroparesis; food intolerances; eosinophilic oesophagitis 95,96. Several authors provided interesting insights into differential diagnoses, with particular reference to conditions affecting the head and neck district which may mimic or overlap with LPRD: chronic rhinosinusitis; autoimmune inflammatory laryngeal disorders (e.g. rheumatoid arthritis, Sjögren syndrome, sarcoidosis, fibromyalgia, musculoskeletal laryngeal disorders); aging voice. Similarly, Carroll et al. identified additional cofactors which may be associated with an “apparently” chronic-recurrent clinical course of LPRD: allergic rhinitis; asthma; chronic laryngitis; glottic insufficiency; post-viral vagal neuropathies 97. Furthermore, active allergies can interfere with the therapeutic management of LPRD, since they may induce laryngeal signs and symptoms which are indistinguishable from those of LPRD.
In addition to pathological gastro-oesophageal or pharyngo-laryngeal conditions which may be associated or non-recognised, several other risk factors related to GERD and LPRD may play a key role in favouring chronic-recurrent clinical courses, even in case of thorough diagnostic approaches and adequate treatment regimens. These risk factors include: inadequate dietary regimens (lack of adherence to the Mediterranean diet); high consumption of specific foods (acid or with high protein or fat content); poor eating habits; tobacco smoke; alcohol abuse; obesity and overweight; sleep disorders; psychosocial distress 98.
Defining the exact recurrence rate with reference to treatment duration represents an additional issue. Success rates of therapy vary between 18% and 87%, but the heterogeneity of published research and the absence of long follow-up periods (often not longer than 6-12 months) make data unhelpful when investigating LPRD recurrences.
Lastly, even if accurate diagnoses and appropriate therapies are ensured, an additional confounding factor could be represented by the scarce compliance of patients towards treatment (poor adherence to dietary restrictions, inappropriate lifestyle, inaccurate timing of medications). According to Barrison et al., poor compliance may represent the first reason for therapeutic failure and a chronic-recurrent clinical course 99.
Conclusions
Although surgical, pharmacological and behavioural therapies for non-oncological voice disorders are widely provided in everyday clinical practice, data on failures and relapse has been little explored. The frequency and the duration of follow-up after treatment for non-oncological voice disorders are heterogeneous, highlighting the need to develop consensus in this area. The available data suggests that failures and relapses are not rare; this information should be regularly transferred to patients before any therapeutic planning. Treatment of failure and relapses is rarely reported; therefore, at the current state of knowledge, it should be decided on the basis of the experience and the skills of each team, which should include at the very least a phonosurgeon, a phoniatrician and a speech and language pathologist. The data from this non-systematic review underlines the urgent need for further research in this area.
Conflict of interest statement
The authors declare no conflict of interest.
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or non-profit sectors.
Author contributions
CR: literature review, paper writing, paper corrections; FM: literature review, supervision; MRB: literature review, paper editing; MB: literature review, paper editing; GC: literature review, paper editing; FD: literature review, paper editing; MG: literature review, paper editing; SR: literature review, paper editing; AS: supervision, paper writing, paper corrections.
Ethical consideration
Not applicable.
Figures and tables
Disease | Author, year | Patients | Follow-up length | Relapses (%) | Post-surgical voice therapy | Relapses treatment |
---|---|---|---|---|---|---|
Polyp | Bouchayer et al., 1992 9 | 267 | n/a | 3/267 (1.12%) | 267 (100%) | n/a |
Hochman et al., 2000 10 | 40 | 2-24 months | 1/40(1.25%) | 35 (87.5%) | Surgery | |
Ju et al., 2013 11 | 118 | 3 months | 7/118 (5.9%) | 55 (46.6%) | n/a | |
Byeon et al., 2013 12 | 280 | 6-12 months | 11/280 (3.9%) | 18 (0.36%) | n/a | |
Zhang et al., 2015 13 | 60 | n/a | 2 /60 (3.33%) | n/a | Surgery | |
Barillari et al., 2017 14 | 70 | 12 months | 4/70 (5.7%) | 70 (100%) | n/a | |
Agarwal et al., 2019 15 | 120 | 5.5 months | 4/120 (3.3%) | 68/91 (74,7%) | n/a | |
Lee et al., 2020 16 | 235 | 13.7 ± 22.3, (0.1-119.8) months | 14/235 (5,53%) | 69% | 7 Voice therapy | |
7 Surgery | ||||||
10 Voice therapy and surgery | ||||||
Patrial et al., 2020 17 | 396 | 0-210 months | 20/396 (5.5%) | n/a | n/a | |
Cyst | Bouchayer et al., 1992 9 | 494 | n/a | 12/494 (2.4%) | 494/494 (100%) | n/a |
Chang et al., 2003 18 | 21 | 3 months | 1/21 (4.8%) | n/a | n/a | |
Hsu et al., 2009 19 | 25 | 12 months | 1/25 (4%) | n/a | n/a | |
Tibbetts et al., 2018 20 | 21 | 5.5 (0.1-54) months | 1/21 (4.8%) | 14/21 (66.7%) | Surgery | |
Lee et al., 2019 16 | 92 | 13.7 (0.1-119.8) months | 2/92 (2.2%) | 69% | n/a | |
Patrial et al., 2020 17 | 349 | 0-210 months | 6/349 (1.7%) | n/a | n/a | |
Reinke’s edema | Nielsen et al., 1986 21 | 111 | 6 months - 8 years | 64/111 (58%) | 55/111 (49.5%) | Surgery |
Bouchayer et al.,1992 9 | 138 | n/a | 3/138 (2.29%) | 138/138 (100%) | n/a | |
Goswami et al., 2003 22 | 92 | 12 months | 4/92 (4.35%) | 92/92 (100%) | n/a | |
Tasar, 2013 23 | 21 | 6 months | 1/21 (4.7%) | n/a | n/a | |
Patrial et al., 2020 17 | 261 | 0-210 months | 8/261 (3.1%) | n/a | n/a | |
Nodules | Nagata et al., 1983 24 | 372: 72 surgery | Over 5 months | 4/36 (11%) surgery | 0/372 | n/a |
300 conservative | 34/101 (33%) | |||||
Lancer et al., 1988 25 | 34 | 5 years | 9/34 (26%) | 20/34 (59%) | n/a | |
Murry et al., 1992 26 | 39 voice therapy | 11/39 voice | 9/39 (23%) | n/a | n/a | |
20 surgery & voice therapy | therapy 20/20 (3 months) | 4/20 (20%) | ||||
Zeitels et al., 2002 27 | 119 | Individualised | 4/119 (3.2%) | 119/119 (100%) | Microsurgery | |
Chernobelsky et al., 2007 28 | 28 voice therapy | Over 10 years | 22 relapses 6 failures | n/a | n/a | |
Bequignon et al., 2013 29 | 62 | 9.5 (5-15) years | 20/62 (32%) | 46 (51%) | n/a |
Disease | Author, year | Patients | Treatment duration/follow-up | Treatment failure/relapses (%) | Relapses management |
---|---|---|---|---|---|
Muscle tension dysphonia | Roy et al., 1997 31 | 25 | 1 session | 13/19 | |
Carding et al., 1999 32 | 45 | 8 weeks | 7/45 (15%) | ||
Lee et al., 2005 33 | 8 | 1-2.5 months | 1/8 (12.5) | ||
Ogawa et al., 2013 34 | 23 | 1 session | 5/23 (21.7%) | ||
Psychogenic dysphonia | Butcher et al., 1987 35 | 19 | n/a | 6/12 | Joint therapy with a speech therapist and a psychologist with a cognitive-behavioural approach |
Reiter et al., 2013 36 | 8 | 16 (± 8) months | 7/8 (88.5%) | n/a | |
Tezcaner et al., 2019 37 | 54 | 21.4 (± 3.7) months follow-up | 10/20 (50%) | Psychological follow-up |
Author, year | Patients | Follow-up lenght | Relapses (%) | Post-surgical voice therapy | Relapses treatment |
---|---|---|---|---|---|
Havas et al., 1999 40 | 51 (12 laryngeal reinnervation) | 24 months | 18/51 (35.3%) | n/a | Not specified. 4 had TP following reinnervation, 4 had TP following injection aumentation |
Maragos, 2001 41 | 331, LFS | n/a | 48/331 (14.5%), | n/a | TP1 45/406 (11.1%); TP2 1/10 (10%), TP3 3/8 (37.5%); TP4 5/45 (11.1%), AA 5/142 (3.5%); AF 2/17 (11.8) |
Woo et al., 2001 42 | n/a, LFS | 0.5 – 132 months | 20 | n/a | Revision ML + AA 9/20 (45%), implant removal 4/20 (20%), revision ML 2/20 (10%), lipoinjection 2/20 (10%), AA 3/20 (15%) |
Cohen et al., 2004 43 | 156, LFS | 1-15 months | 16/156 (10.2%) | n/a | Revision Gore-Tex ML 9/22 (40,9%), injection augmentation 9/22 (40,9%), implant removal 2/22 (9,09%), AA 2/22 (9,09%). |
Parker et al., 2015 44 | 208, LFS | 14.6 months | 39/208 (18.7%) | n/a | Injection ML prior to revision ML in 14/48 (29%) surgeries. 28 AUG; 1 arytenopexy; 3 AUG + arytenopexy; 1 AUG + cricothyroid subluxation; 2 arytenopexy + cricothyroid subluxation; 11 AUG + arytenopexy + cricothyroid subluxation. |
Kwak et al., 2016 45 | 40 TP | 46.5 months | 6/40 (15%) | n/a | 6 revision TP |
Silva Merea et al., 2018 46 | 135 ML (56 with prior injection augmentation) | unclear | 14 (10,4%): 5/56 (8.9%) of those with prior IA + 9/79 (11.4%) of those with no prior IA | n/a | 6 removal of old implant + new implant + AA; 3 removal of old implant + new implant; 1 addition of new implant; 1 removal of old implant + new implant + contralateral medialisation; 1 removal of old implant + new implant + AA + pharyngoplasty; 1 partial removal of implant + AA |
Marie et al., 2020 47 | n/a. Previous TP or VF augmentation | 36 months | 8 | n/a | 8 unilateral laryngeal reinnervation (ansa to RLN) |
Prstačić et al., 2020 49 | 78, IA | 12 months (unclear) | 8/78 (10.3%) | Before fat augmentation | Second surgery not specified |
Kishimoto et al., 2020 48 | 149 | 1-109 months | 19 pz (12,75%) | n/n | Revision framework surgery (TP1 13; AA 5; TP1+TP4 1; TP1+AA 2) |
Mes et al., 2021 50 | 61, LFS | >12 months | 6 (9.8%) | n/a | 3 additional AA, 3 injection augmentation |
Miaśkiewicz et al.,2021 51 | 51, IA | 36 months | 18/51(35%) | yes | 18 reinjections |
Author, year | Primary treatment | Patients | Follow-up duration | Relapses (%) | Post-surgical voice therapy | Relapses treatment |
---|---|---|---|---|---|---|
Dennis et al., 1989 52 | Posterior cordectomy | 6 | 1-5 years | n/a | no | n/a |
Laccourreye et al., 1999 53 | Posterior partial transverse cordotomy | 25 | 10 months | n/a | no | n/a |
Pia et al., 1999 54 | Posterior ventriculocordectomy | 41 | 43 months | n/a | no | n/a |
Manolopoulos et al., 1999 55 | Partial posterior cordectomy | 18 | 0.6-6 years | 2 (11%) | no | Revision surgery |
Maurizi et al., 1999 56 | Subtotal arytenoidectomy and medial-posterior cordotomy | 39 | 30 months | 5(12,8%) | no | Revision surgery |
Hans et al., 2000 57 | Posterior transverse cordotomy | 4 | 24 months | 0 | no | n/a |
Segas et al., 2001 58 | Unilateral posterior ventricular cordectomy | 20 | n/a | n/a | no | n/a |
Dursun et al., 2006 59 | Posterior transverse laser cordotomy | 22 | 14-48 months | 4 (18%) | no | Revision surgery |
Misiolek et al., 2007 60 | Total arytenoidectomy with posterior cordectomy | 30 | 5 years | 0 | no | n/a |
Harnisch et al., 2008 61 | Posterior cordectomy (n = 2), laterofixation (n = 1), posterior trans- verse cordotomy(n = 7) | 10 | 6-57 months | 1 (10%) | yes | Revision surgery |
Bajaj et al., 2009 62 | Bilateral posterior vocal fold release | 9 | 0.3-4 years | 1(11%) | no | Conservative treatment |
Hyodo et al., 2009 63 | Laterofixation | 11 | 3-80 months | 1 (9%) | no | n/a |
Ezzat et al., 2010 64 | Laterofixation | 21 | 6 months | n/a | no | n/a |
Riffat et al., 2012 65 | Unilateral laser posterior cordotomy (n = 12), bilateral posterior cordotomy (n = 8), combined cordotomy and arytenoi- dectomy (n = 9), excision of a posterior glottic scar (n = 5) | 34 | 24 months | n/a | no | n/a |
Yilmaz, 2012 66 | Total arytenoidectomy, vocal fold lateralization | 50 | 1-3 years | 3(6%) | no | Revision surgery |
Nawka et al., 2015 67 | Posterior chordotomy, partial or total arytenoidectomy, permanent laterofixation | 32 | 6 month | 0 | no | n/a |
Asik et al., 2016 68 | Monolateral posterior transverse cordotomy | 11 | 2 months | 0 | no | n/a |
Fabre et al., 2019 69 | Vocal fold lateralization | 18 | n/a | n/a | no | n/a |
Rashid et al., 2019 70 | Posterior cordotomy | 34 | 2 months | 6 (17,6%) | no | n/a |
Qazi et al., 2021 71 | Transverse posterior cordotomy | 20 | 442 days | 5 (25%) | no | Revision surgery |
Filauro et al., 2021 72 | Posterior cordotomy (± medial partial arytenoidectomy) | 33 | n/a | 6 (18,1%) | no | Revision surgery |
Ghodke et al., 2021 73 | Transverse cordotomy with anteromedial arytenoidectomy | 10 | n/a | n/a | no | n/a |
Benninger et al., 2022 74 | Unilateral coblator cordotomy | 94 | 16 months | n/a | no | n/a |
Author, Year | Treatment | Patients | Follow-up lenght | Relapses (%) | Post-surgical voice therapy | Relapses treatment |
---|---|---|---|---|---|---|
Aronson et al., 1983 75 | LNR | 33 | 36 months | 21 (63.64%) | n/a | Not reported |
Berke et al., 1999 76 | SLAD-R | 21 | 36 months | 4 (19.05%) | n/a | 1/4 (25%) BTX, 1/4 (25%) collagen injection, 1/4 (25%) TMN, 1/4 voice therapy |
Smith et al., 2000 77 | BTX-ona | 2 | 3-7 years | 2 (100%) | n/a | No further treatment |
Galardi et al., 2001 78 | BTX-ona, BTX-abo | 15 | 3.53 years (1-8) | 12 (80%) pt had ³ 1 non effective injection | n/a | n/a |
Park et al., 2003 79 | BTX-ona | 71 | 5 years | 6 (8.45%) | n/a | n/a |
Isshiki et al., 2004 80 | TPII | 25 | 3-6 months | 1 (4.0%) | n/a | Revision TPII with TB (1/1, 100%) |
Chhetri et al., 2006 81 | SLAD-R | 83 | 49 months | 12 (14.46%) | n/a | 5/12 (41.67%) BTX; 7/12 (58.33%) not reported |
Cannito et al., 2008 82 | BTX-ona | 42 | 3-6 weeks | 7 (16.67%) all over 70 years of age | n/a | n/a |
Sanuki et al., 2009 83 | TPII | 90 | 12-36 months | 7 (7.78%) | 1 | 2/7 (28.57%) removal of goretex or TB, no revision surgery; 5/7 (71.43%) new TB |
Su et al., 2010 84 | TMN | 29 | 31 (12-63) months | 11 (37.93): 3 (10.34%) unsuccessful surgery | n/a | Revision TMN (7/8, 87.5%) |
Sanuki et al., 2010 85 | TPII | 10 | 17.6 (7-25) months | 0 (0.0%) | n/a | - |
Tsuji et al., 2012 86 | TMN | 15 | 31 (4-96) months | 2 (13.33%) | n/a | n/a |
Nomoto et al., 2015 87 | TMN vs TPII | 65 (30 TMN, 35 TPII) | 6 months | 1 TMN (3.33%) | n/a | Revision TMN 1/1 (100%) |
Schuering et al., 2020 88 | TMN | 22 | 30 months | 10 (45.45%) | n/a | TMN 10/10 (100%) |
Zhao et al., 2020 89 | BTX-ona | 131 | n/a | 67 (12%) injections | n/a | n/a |
Kohli et al., 2022 90 | BTX-inc | 9 | 2.56 months | 4 non responders | n/a | n/a |
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