Claudio Storck

Reliable jitter and shimmer measurements in voice clinics : the relevance of vowel, gender, vocal intensity, and fundamental frequency effects in a typical clinical task

The aims of this study were to examine vowel and gender effects on jitter and shimmer in a typical clinical voice task while correcting for the confounding effects of voice sound pressure level (SPL) and fundamental frequency (F(0)). Furthermore the relative effect sizes of vowel, gender, voice SPL, and F(0) were assessed, and recommendations for clinical measurements were derived. With this cross-sectional single cohort study, 57 healthy adults (28 women, 29 men) aged 20-40 years were investigated. Three phonations of /a/, /o/, and /i/ at normal voice loudness were analyzed using Praat (software). The effects of vowel, gender, voice SPL, and F(0) on jitter and shimmer were assessed using descriptive and inferential (analysis of covariance) statistics. The effect sizes were determined with the eta-squared statistic. Vowels, gender, voice SPL, and F(0), each had significant effects either on jitter or on shimmer, or both. Voice SPL was the most important factor, whereas vowel, gender, and F(0) effects were comparatively small. Because men had systematically higher voice SPL, the gender effects on jitter and shimmer were smaller when correcting for SPL and F(0). Surprisingly, in clinical assessments, voice SPL has the single biggest impact on jitter and shimmer. Vowel and gender effects were clinically important, whereas fundamental frequency had a relatively small influence. Phonations at a predefined voice SPL (80 dB minimum) and vowel (/a/) would enhance measurement reliability. Furthermore, gender-specific thresholds applying these guidelines should be established. However, the efficiency of these measures should be verified and tested with patients.

Changes in self-perceived role identity modulate pain perception.

Abstract Pain is an experience including physiological and psychological factors. We assume that emotions may be elicited and increased through self‐perceived role identity and that change of role identity alters quality and intensity of pain perception. We used role‐play strategies to assess whether pain can be better tolerated whenever, in an unavoidable and unpleasant context, role identity confers pain a meaningful and thus suitable character. We induced antithetic roles in 21 actors who received heat stimuli on their arms before and after role‐play conditions. Pain tolerance, skin conductance and voice signals were measured. Pain tolerance increased for heroes/heroines and decreased for faint‐hearts. Men showed higher pain tolerance. Heroes/heroines evaluated heat stimuli as more intense. Faint‐hearts found pain stimuli more affectively loaded at lower temperatures. Women showed higher pain ratings. Hence, self‐perception influences pain perception. Role‐play strategies may be of value for new pain management strategies.

Functional outcome of vocal fold medialization thyroplasty with a hydroxyapatite implant.

Objectives: Unilateral vocal fold paralysis can cause a persistent incomplete glottal closure during phonation, resulting in impaired voice function. The aim of this study was to evaluate functional results of medialization thyroplasty using a hydroxyapatite implant (VoCoM).

Co-overexpression of p21 and Ki-67 in head and neck squamous cell carcinoma relative to a significantly poor prognosis

Head and neck squamous cell carcinomas (HNSCC) are treated by surgery or radiotherapy. Tumor cell death–related markers, such as p21 and Ki‐67, may predict response to therapy and improve treatment choice. We evaluated and compared the effect of their coexpression between patients treated by surgery or radiotherapy.

Hydroxyapatite versus titanium implant: Comparison of the functional outcome after vocal fold medialization in unilateral recurrent nerve paralysis

Results of medialization thyroplasty for treatment of unilateral vocal fold paralysis are often unsatisfactory. This study compares glottal closure and voice quality after use of 2 different medialization implant types: VoCoM and TVFMI.

Partial cricotracheal resection for successful reversal of laryngotracheal separation in patients with chronic aspiration.

Objective: To present our experience with successful reversal of laryngotracheal separation in patients with chronic aspiration, to discuss our surgical technique, and to review the literature.

Biomechanics of the cricoarytenoid joint: three-dimensional imaging and vector analysis.

OBJECTIVES/HYPOTHESISnLaryngeal framework surgery requires a good understanding of the biomechanics of the cricoarytenoid (CA) joint, the precise function of which is still only poorly understood. The aim of the study was (1) to show that, by superimposing two or more three-dimensional (3D) images, we can visualize the exact position of the arytenoid cartilages within the larynx at different phases of their movement; and (2) to demonstrate that it is possible to analyze the arytenoid cartilage movements mathematically with the help of vector analysis.nnnSTUDY DESIGNnIn vitro cadaver study.nnnMETHODSnTwenty fresh and intact cadaver larynges were scanned by high-resolution computerized tomography with the arytenoid cartilages in respiratory position and in phonatory position. The two positions were superimposed and rendered in 3D with MIMICS (Materialise Interactive Medical Image Control System, Leuven, Belgium). The spatial trajectory of the arytenoid cartilage movements was calculated with vector analysis.nnnRESULTSnThe movement from the respiratory to the phonatory position has three components: (1) an inward rocking action around the longitudinal CA joint; (2) a forward sliding movement along the longitudinal axis of the CA joint; and (3) an inward rotation around a virtual axis that runs perpendicular to the CA joint axis.nnnCONCLUSIONSnSuperimposing 3D images of the larynx with the help of the software package MIMICS allows us to visualize and to analyze mathematically the trajectory of the arytenoid cartilage. The arytenoid cartilages rock inward, slide forward, and rotate inward when they move from the respiratory to the phonatory position.

Cricothyroid joint anatomy as a predicting factor for success of cricoid-thyroid approximation in transwomen.

Cricoid‐thyroid approximation (CTA) performed to elevate the vocal pitch in transwomen fails in about one‐third of the patients. The purpose of this study was to test the feasibility of predicting the likelihood of success of CTA by preoperative determination of the crico‐thyroid joint (CTJ) type using three‐dimensional (3‐D) images derived from high‐resolution computer tomography (HRCT).

Laryngeal electromyography: electrode guidance based on 3-dimensional magnetic resonance tomography images of the larynx.

OBJECTIVES/HYPOTHESISnLaryngeal electromyography (LEMG) is an important tool for the assessment of laryngeal nerve and muscle functioning. The purpose of the study was to determine electrode insertion angle and insertion depth for the various laryngeal muscles.nnnMETHODSnTwenty-three cadaver larynges were examined with magnetic resonance tomography (MRT) and Materialize Interactive Medical Image Control System (Leuven, Belgium) 3-dimensional (3D) imaging software. Geometrical analysis was used to calculate the electrode insertion angles.nnnRESULTSnAll laryngeal muscles could be identified and 3D visualized on MRT scans. Although the insertion angles were the same in male and female larynges, the insertion depth was significantly larger in male than in female larynges (P<0.05). Of particular clinical importance is the fact that the electrode has to be directed lateral and upward for the thyroarytenoid muscle but lateral and downward for the lateral cricoarytenoid muscle (insertion point=midline lower border of the thyroid).nnnCONCLUSIONSnThis is the first study that analyzes electrode insertion angles and insertion depths for each laryngeal muscle using 3D imaging. We hope that the information gained from this study will help clinicians performing LEMG to localize the individual laryngeal muscles.

3D analysis of the movements of the laryngeal cartilages during singing

The vocal range of untrained singers rarely exceeds one and a half octaves, but professional singers have a range of at least two and a half octaves. The aim of this study was to better understand the muscle and cartilage movements responsible for the control of vocal pitch in singing.