Acute Vocal Fold Paresis and Paralysis After COVID-19 Infection: A Case Series

Objective: Evidence demonstrates neurotropism is a common feature of coronaviruses. In our laryngology clinics we have noted an increase in cases of “idiopathic” vocal fold paralysis and paresis in patients with no history of intubation who are recovering from the novel SARS-Cov-2 coronavirus (COVID-19). This finding is concerning for a post-viral vagal neuropathy (PVVN) as a result of infection with COVID-19. Our objective is to raise the possibility that vocal fold paresis may be an additional neuropathic sequela of infection with COVID-19. Methods: Retrospective review of patients who tested positive for COVID-19, had no history of intubation as a result of their infection, and subsequently presented with vocal fold paresis between May 2020 and January 2021. Charts were reviewed for demographic information, confirmation of COVID-19 infection, presenting symptoms, laryngoscopy and stroboscopy exam findings, and laryngeal electromyography (LEMG) results. Results: Sixteen patients presented with new-onset dysphonia during and after recovering from a COVID-19 infection and were found to have unilateral or bilateral vocal fold paresis or paralysis. LEMG was performed in 25% of patients and confirmed the diagnosis of neuropathy in these cases. Conclusions: We believe that COVID-19 can cause a PVVN resulting in abnormal vocal fold mobility. This diagnosis should be included in the constellation of morbidities that can result from COVID-19 as the otolaryngologist can identify this entity through careful history and examination.

Diagnostic limitation of laryngostroboscopy in comparison to laryngeal electromyography in synkinesis in unilateral vocal fold paralysis

Purpose In clinical practice, laryngo(strobo)scopy (LS) is still mainly used for diagnostics and management of unilateral vocal fold paralysis (UFVP), although only laryngeal electromyography (LEMG) can provide information on causes of vocal fold immobility, especially on possible synkinetic reinnervation after recurrent laryngeal nerve (RLN) injury. The goal of this retrospective study was the evaluation whether signs of synkinetic reinnervation in LS can be objectified in comparison to LEMG data. Methods Between 1/2015 and 2/2018, 50 patients with laryngostroboscopically suspected UVFP received routine LEMG examination. The LEMG findings were retrospectively compared with LS findings. The LEMG data analysis focused on the diagnosis of synkinetic reinnervation of the TA/LCA and/or PCA. The digital LS recordings were retrospectively re-evaluated by phoniatricians considering 22 selected laryngostroboscopic parameters. Results LEMG revealed synkinesis in 23 (46%) and absence of synkinesis in 27 (54%) patients. None of the 22 parameters showed significant association between patients with synkinetic reinnervation and LS findings. The only laryngostroboscopic parameter that was significantly associated with a silent LEMG signal compared to single fiber activity in LEMG was a length difference on the side of the UVFP (p-value 0.0001; OR 14.5 (95% CI 3.047–66.81; Sensitivity 0.5; Specificity 0.9355). Conclusion Our findings show that synkinesis cannot be diagnosed using only LS. This study underlines the importance of LEMG in clinical routine for detection of laryngeal synkinesis in patients with UVFP before any further therapeutic steps are initiated to avoid later therapy failure.