xRead - Swallowing Disorders in the Adult Patient (October 2024)

10976817, 2023, 1, Downloaded from https://aao-hnsfjournals.onlinelibrary.wiley.com/doi/10.1177/01945998211072832 by University Of Miami Libraries, Wiley Online Library on [01/07/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License

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10 Coulter et al

Otolaryngology–Head and Neck Surgery

to outcome heterogeneity. They concluded that the quality of the evidence was insufficient to support the procedure, rea soning that none of the studies used a control group; therefore, no study could reasonably conclude that improvements were due to the intervention and not due to spontaneous recovery of function. The current study excluded most of the studies focused on acute IL from the quantitative analysis because evaluation for recovery of vocal fold mobility following IL was not documented. There were, though, 2 smaller stud ies 35,41 that did account for this and still showed significant benefit in subjects who did not recover function. Additionally, while spontaneous recovery may be a significant source of bias in the acute phase of UVFI, the current study evaluated IL, LF, and LR procedures over a variety of periods by a vari ety of outcome measures and found similar high rates of suc cess for all procedures. Given that LF surgery is presumably performed only in UVFI that would likely be considered per manent and that outcomes were similar between IL and LF, we feel that one could consider IL and LF viable treatment options for dysphagia associated with UVFI despite the asser tions made in regard to IL in acute UVFI. Additionally, although the current analysis involved cohort studies and case series, the lack of controls did not preclude a quantitative analysis of the pooled data, demonstrating significant improvement after intervention. Given the severe impairment that dysphagia imparts to quality of life, nutritional status, and overall health, as well as the life-threatening risk of aspiration, the success rate of medialization procedures seems to out weigh the low rate of complications. In counseling patients with UVFI and dysphagia on the effects of medialization procedures, the current data indicate that IL, LF, and LR are all beneficial. Dysphagia outcomes seem to mirror voice outcomes after medialization procedures for UVFI in that clear superiority of a specific medialization procedure cannot be distinguished. 49,50 The nuances of the optimal treatment method in particular scenarios are unfortu nately beyond the limits of the current data set but would likely be related to the natural history of the disease process, the extent of functional deficit, the size and configuration of the glottal gap, patient age and comorbidities, overall quality of life, and potential adverse effects of treatment. Although this study could not extract the details of the etiology of each case of UVFI and dysphagia outcomes, it is plausible that different causes may lead to variable results. For example, a central neurologic or high vagal nerve injury may lead to sig nificantly worse dysphagia due to concurrent sensory and motor impairment, which may respond more favorably to LF surgery (specifically arytenoid adduction) or adjunct proce dures such as cricopharyngeal myotomy. However, IL can be performed at the bedside or in the office and therefore can typically be done very quickly. Although IL may need to be repeated, as most of the injectable materials resorb over time, it does allow for natural recovery or can serve as a bridge to procedures such as LF and LR, which are thought to provide more durable and sustainable benefits. Decision making in this regard could be improved if future studies focus on indications for each medialization procedure in specific circumstances.

The lack of objective and standardized reporting of out comes is a limitation of the dysphagia literature in general and thus conclusions from this body of work. Realizing the utility of objective measures of dysphagia and attempts to standar dize reporting of dysphagia outcomes will strengthen future research. Ensuring that outcomes data is quantifiable and indi vidually extractable could facilitate a more in-depth and focused systematic review and meta-analysis with higher quality. Additionally, new technology could supplant tradi tional treatment modalities for UFVI. Specifically, tissue engineering may allow for injectable growth factors to stimu late hyaluronic acid production and increase bulk to restore glottal competence. 51,52 This is a unique study that pools the available data to quan titatively and qualitatively assess dysphagia outcomes in those with UVFI undergoing surgery to improve glottal com petence. There is no other published systematic review or meta-analysis to our knowledge focusing on the impact of vocal fold medialization procedures in patients with dyspha gia and UVFI. The current literature on dysphagia outcomes after medialization procedures for those with UVFI is hetero genous, mostly retrospective, and largely observational, thus limiting the ability to draw robust conclusions regarding the extent of benefit postoperatively. To conduct this study, the various heterogeneous outcome measures of each study were dichotomized into success or failure. This approach admit tedly reduces the precision of recommendations that can be made as a result of this analysis. Yet, it does provide justifica tion to pursue medialization procedures in the presence of dysphagia and UVFI despite these shortcomings, with the knowledge that restoring glottal competence may not com pletely normalize an individual’s swallowing function, espe cially in the context of more severe deficits associated with high vagal nerve and central insults. Randomization and the use of control groups would be greatly beneficial in regard to constructing more powerful meta-analyses in the future. Nev ertheless, it seems impractical and potentially dangerous to plan and conduct a comparative study where individuals with aspiration, for example, could be randomized to a ‘‘no treat ment’’ group, thus placing them at higher risk for poor nutri tion and pneumonia. This analysis did not directly compare surgical outcomes with other conservative interventions, such as diet modifica tion or dysphagia therapy, although these conservative thera pies are not typically chosen as an alternative to surgical management; rather, they are often instituted prior to consid eration of surgical management or to maximize benefit of sur gical treatment postoperatively. Elucidating the optimal role of dysphagia therapy in this patient population, especially as it relates to complementing medialization procedures, is an important question for future research. Although it appears clear that the majority of patients bene fit from surgical management of dysphagia related to UVFI, most studies were categorized as having a high risk of bias based on MINORS criteria, thus weakening the strength of our findings. Although the risk of bias in the data introduces limitations, the number of studies and consistency of findings