Relationship Between Laryngeal Electromyography and Video Laryngostroboscopy in Vocal Fold Paralysis

Arytenoid asymmetry: Is it the most predictive parameter for arytenoid adduction in unilateral vocal fold paralysis?

OBJECTIVE

The aim of this study was to establish arytenoid asymmetry as a pre-operative predictive parameter for arytenoid adduction surgery in unilateral vocal fold paralysis and thereafter identify the most predictive parameter for arytenoid adduction among the established parameters.

METHODS

A retrospective comparative study was undertaken. The 'arytenoid asymmetry angle' formed between skewed 'glottic' and 'interarytenoid' axes (traced along the plane of closure of the membranous and cartilaginous glottis, respectively) was quantified in pre-operative laryngoscopic images of 85 adults with unilateral vocal fold paralysis who underwent either type 1 thyroplasty (group 1) or type 1 thyroplasty with arytenoid adduction (group 2). The need for arytenoid adduction was determined intra-operatively based on subjective voice improvement and laryngoscopic results.

RESULTS

Arytenoid asymmetry (p < 0.0001), posterior phonatory gap (p = 0.001) and vertical level difference (p = 0.004) were significantly greater in group 2 (descending order of parameters). Arytenoid asymmetry angle showed a significant positive correlation with the latter two parameters.

CONCLUSION

Arytenoid asymmetry is the most predictive parameter for arytenoid adduction. An arytenoid asymmetry angle of more than or equal to 33.9⁰ is an indication for arytenoid adduction. This aids in pre-operative planning of arytenoid adduction.

Vocal Fold "Paralysis": An Early Sign in Multiple System Atrophy

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by a cerebellar syndrome, autonomic dysfunction, and extrapyramidal signs. Extrapyramidal signs may manifest as parkinsonism as well as dystonia, which is the involuntary contraction of a muscle(s) resulting in an abnormal posture. MSA belongs to a family of diseases known as α-synucleinopathies which are associated with dream enactment reflecting REM sleep behavior disorder (RBD). In patients with MSA, dystonia or paresis may involve the laryngeal muscles resulting in vocal fold hypomobility. We identified four individuals presenting with vocal complaints and subsequently diagnosed with vocal fold "paralysis." Within one year, each patient developed neurologic symptoms and upon evaluation by a movement disorders specialist was diagnosed with probable MSA. Our findings highlight the importance of screening by otolaryngologists when patients are diagnosed with vocal fold hypomobility. Specifically, patients should be assessed for RBD by questioning others if he/she acts out their dreams. The presence of RBD raises clinical suspicion for a synucleinopathy such as MSA. Untreated patients with MSA experiencing nocturnal stridor and breathing disorders have an increased risk for sudden death. Therefore, early evaluation by a movement disorders specialist to promptly diagnose MSA may have a substantial effect on morbidity and mortality in this high-risk patient population.

Vocal fold paresis: Medical specialists' opinions on standard diagnostics and laryngeal findings

PURPOSE

There is still no clear consensus on the diagnostic value of specific laryngeal findings in patients with suspected vocal fold paresis (VFP). The aim of the study was to establish expert opinion on criteria for the diagnosis of VFP in Europe.

METHODS

A cross-sectional survey using the questionnaire introduced by Wu and Sulica for US American experts was addressed to laryngeal experts in Germany, Austria, and Switzerland and in a second survey wave to members of the European Laryngological Society.

RESULTS

100 respondents returned survey 1 (response rate 47.2%). 26% worked at a university department. 28% regularly used laryngeal electromyography (LEMG). A pathologic test results in LEMG was considered to have the strongest positive predictive value for VFP (79 ± 23%), followed by a decreased vocal fold abduction (70 ± 29%), decreased vocal fold adduction (61 ± 34%), and atrophy of the hemilarynx (61 ± 31%). The multivariate analysis showed the predictive value of LEMG was estimated lower by respondents from non-university hospital (β = - 16.33; confidence interval (CI) = - 25.63 to - 7.02; p = 0.001) and higher in hospitals with higher frequency of VFP patients per months (β = 1.57; CI = - 0.98 to 2.16; p < 0.0001). 30 ELS members returned survey 2 (response rate, 8.4%). Their answers were not significantly different to survey 1.

CONCLUSIONS

The laryngology experts in Europe rely on LEMG for diagnosis of VFP like the US American experts, but paradoxically only a minority uses LEMG frequently. Next to LEMG, motion abnormities were considered to have the best predictive value for the diagnosis of VFP.