Using laryngeal electromyography to differentiate presbylarynges from paresis

Predicting Airflow from Measures Sensitive to Mid-cord Glottal Gap During the COVID-19 Pandemic

OBJECTIVES

To determine if trans-laryngeal airflow, important in assessing vocal function in paresis/paralysis and presbylarynges patients with mid-cord glottal gaps, could be predicted by other measures sensitive to mid-cord glottal gap size but with smaller risks of spreading COVID-19, and if any patient factors need consideration.

METHODS

Four populations were: unilateral vocal fold paresis/paralysis (UVFP, 148), aging and UVFP (UVFP plus aging, 22), bilateral vocal fold paresis/paralysis without airway obstruction (BVFP, 49), and presbylarynges (66). Five measures were selected from the initial clinic visit: mean airflow from repeated /pi/ syllables, longer of 2 /s/ and 2 /z/ productions, higher of 2 cepstral peak prominence smoothed for vowel /a/ (CPPSa), and Glottal Function Index (GFI). S/Z ratios were computed. Stepwise regression models used 3 measures and 5 patient factors (age, sex, etiology, diagnosis, and potentially impaired power source for voicing) to predict airflow.

RESULTS

Log-transformations were required to normalize distributions of airflow and S/Z ratio. The final model revealed age, sex, impaired power source, log-transformed S/Z ratio, and GFI predicted log-transformed airflow (R2 = .275, F[5,278] = 21.1; P < .001).

CONCLUSIONS

The amount of variance explained by the model was not high, suggesting adding other predictive variables to the model might increase the variance explained.

Treatment effectiveness for aging changes in the larynx

OBJECTIVES

To compare the effectiveness of injection augmentation and bilateral thyroplasty surgery in managing age-related changes of the larynx.

STUDY DESIGN

Retrospective chart review of patients treated with bilateral thyroplasty and/or injection augmentation.

METHODS

We evaluated 22 patients before and after treatment using: 1) normalized glottal gap area and normalized true vocal fold width from endoscopic images; 2) patient self-rating questionnaires; and 3) acoustic and aerodynamic measures.

RESULTS

Thyroplasty surgery resulted in 38% of patients demonstrating less bowing compared to 33% after injection, and 63% demonstrated less supraglottic activity compared to 43% after injection (P = 0.09). Change in mean Voice-Related Quality of Life (V-RQOL) scores was 25.5 after thyroplasty compared to -16.4 after injection (P < 0.05). Those exhibiting a greater than 20 change in V-RQOL after treatment were significantly more likely to report swallowing symptoms pretreatment.

CONCLUSION

Patients postinjection did not rate themselves on any questionnaires as significantly better compared to pretreatment, whereas patients post-thyroplasty rated themselves as significantly improved on all questionnaires. Patients post-thyroplasty rated their voices as significantly closer to their best voice than patients postinjection. Likewise, 64% of patients who had thyroplasty surgery reported a significant treatment effect compared to 33% for injection augmentation.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:2572-2577, 2017.

Vocal fold paresis – a debilitating and underdiagnosed condition

Objectives:

To review the clinical signs of vocal fold paresis on laryngeal videostroboscopy, to quantify its impact on patients’ quality of life and to confirm the benefit of laryngeal electromyography in its diagnosis.

Methods:

Twenty-nine vocal fold paresis patients were referred for laryngeal electromyography. Voice Handicap Index 10 results were compared to 43 patients diagnosed with vocal fold paralysis. Laryngeal videostroboscopy analysis was conducted to determine side of paresis.

Results:

Blinded laryngeal electromyography confirmed vocal fold paresis in 92.6 per cent of cases, with vocal fold lag being the most common diagnostic sign. The laryngology team accurately predicted side of paresis in 76 per cent of cases. Total Voice Handicap Index 10 responses were not significantly different between vocal fold paralysis and vocal fold paresis groups (26.08 ± 0.21 and 22.93 ± 0.17, respectively).

Conclusion:

Vocal fold paresis has a significant impact on quality of life. This study shows that laryngeal electromyography is an important diagnostic tool. Patients with persisting dysphonia and apparently normal vocal fold movement, who fail to respond to appropriate speech therapy, should be investigated for a diagnosis of vocal fold paresis.

[Treatment of glottal gap]

Glottal gaps can be either physiological or pathological. The latter are multifactorial, predominantly organic in origin and occasionally functional. Organic causes include vocal fold paralysis or scarring, as well as a deficiency or excess of tissue. In addition to loss of the mucosal wave, the degree of hoarseness is primarily determined by the circumferential area of the glottal gap. It is thus important to quantify the extent of glottal insufficiency. Although a patient's symptoms form the basis for treatment decisions, these may be subjective and inadequately reflected by the results of auditory-perceptual evaluation, voice analysis and voice performance tests. The therapeutic approach should always combine phonosurgery with conventional voice therapy methods. Voice therapy utilises all the resources made available by the sphincter model of the aerodigestive tract and knowledge on the mechanism of voice production. The aim of phonosurgery is medialization, reconstruction or reinnervation by injection laryngoplasty or larynx framework surgery. These different methods can be combined and often applied directly after vocal fold surgery (primary reconstruction). In conclusion, the techniques described here can be effectively employed to compensate for glottal gaps.

Frame by frame analysis of glottic insufficiency using laryngovideostroboscopy

OBJECTIVES/HYPOTHESIS

Glottic insufficiency (GI) can be either grossly obvious or subtle in its presentation. Subtle GI is demonstrated by various Laryngovideostroboscopic (LVS) clues, including complete but "short" phase closure of the true vocal folds (VFs) during the glottic cycle. We used the frame by frame analysis (FBFA) technique to evaluate its effectiveness in objectively contributing to the diagnosis of subtle GI in patients with atrophic and/or paretic VFs. This article intends to formally present the methods and intentions of the FBFA technique and report our findings using FBFA on subjects with clinically diagnosed GI and normal volunteers.

STUDY DESIGN

Retrospective review and demonstration of technique.

METHODS

Forty-four subjects with a prior clinical diagnosis of true VF atrophy (25/44) and/or paresis (19/44) and five normal volunteers were identified. Using the FBFA technique, each subject's average percentage of closed frames per glottic cycle was recorded.

RESULTS

Subjects with atrophy spent 32.4% of the frames of the glottic cycle in the closed phase, subjects with paresis spent 35.7% of the frames closed, and normal subjects spent 50.2% of the frames closed.

CONCLUSIONS

FBFA appears to be a simple objective method for the novice or experienced LVS interpreter, by which one can suspect subtle GI. Because of the inherent physical properties by which LVS gives an "illusionary" representation of the glottic cycle, the FBFA technique remains a theoretical tool. Future studies using high-speed digital imaging are needed to validate this useful technique.