Michèle Boiron

Origin of the Sound Components During Pharyngeal Swallowing in Normal Subjects

The aim of this study was to identify the origin of swallowing sound components by using modern techniques that can provide numeric, synchronized acoustic–radiologic data. We enrolled 15 volunteer subjects (10 men and 5 women, average age = 29.5 ± 8 years) and used an X-ray camera connected to a video acquisition card to obtain synchronized acoustic–radiologic data (25 images/s). The subjects were asked to swallow 10 ml of a barium suspension. Each sound component was associated with a specific position of the bolus and the anatomic structure that was moving. The average duration of the pharyngeal sound was 690 ± 162 ms. The durations of the laryngeal ascension sound and the laryngeal release sound were significantly different (72 ± 38 ms and 106 ± 47 ms, p < 0.001). The upper-sphincter opening sound was present in 100% of the recordings. Its duration was 185 ± 103 ms and was significantly different from the two other sounds. The duration of the first interval was 108 ± 44 ms and the duration of the second was 236 ± 139 ms. This study allowed us to determine the origin of the three main sound components of the pharyngeal swallowing sound with respect to movements in anatomic structures and the different bolus positions.

Sound component duration of healthy human pharyngoesophageal swallowing: a gender comparison study.

Cervical auscultation is a noninvasive technique for studying swallowing that was first used in the 1960s. The aim of our study was to use the numeric acoustic recording technique for analyzing swallowing sound signals in healthy subjects while they ingested a defined volume and consistency of a specific substance. Twenty males and ten females were included in the study and given 10 ml of a barium suspension to swallow. A microphone was placed on the skin overlying the lateral border of the trachea, directly under the inferior border of the cricoid, and connected to a computer. For each sound recording, the total duration of the sound (td), the number (n) of sound components (SC), the duration of each SC (c1, c2, c3,...), and the intervals (i1, i2,...) between the SCs were measured. For all the recordings, the mean durations of acoustic parameters (TDm, C1m, C2m, C3m, I1m, I2m) were calculated and compared by using Student’s t test. In the 20 male subjects, the mean acoustic parameters were calculated (MTDm, MC1m, MC2m, MC3m, MI1m, MI2m) and compared with the mean acoustic parameters (FTDm, FC1m, FC2m, FC3m, FI1m, FI2m) in the ten females by using a Wilcoxon nonparametric statistical test. We were able to interpret 80% of the recordings. The TDm was 710 ± 28 ms. Three main SCs were detected: C1m = 100 ± 56, C2m = 150 ± 90, C3m = 80 ± 54 ms; I1m = 100 ± 66, I2m = 190 ± 120 ms. No significant difference in these parameters was observed with respect to gender. This study enabled us to decompose the swallowing sounds into three main SCs and to quantify their normal durations. These results should prove useful for the assessment of sound variations in pathologic conditions.

Comparison of audio signal codings for Zipf analysis of xiphoidal sounds

We present in this paper a comparison of audio signal codings that we have developed in order to study xiphoidal sounds. These sounds are produced by the lower oesophageal sphincter whose dysfonctionnement can be responsible for the gastro-eosophageal reflux phenomenon. Our goal is to extract pertinent information from audio signals in order to characterize the pathology of the patients and its intensity, which is generally realized by invasive and traumatic methods such as radiological and manometric investigations. Several codings of audio signals are presented and compared. They are based on different representations of signals: temporal, frequential and time-scale representations. Zipf and inverse Zipf analyses are then performed. They allow the extraction of pertinent primitives, not available from standard signal processing methods. Finally, a clustering step is realized in order to bring to the fore clusters, linked to pathology characteristics. Two clustering methods have been used: a linear discriminant analysis, and a neural network clustering method.

Ultrasound Study of the Normal Upper Esophageal Sphincter

Objective: The purpose of this study was to develop a methodology and standard settings for ultrasound study of the upper esophageal sphincter (UES) during swallowing. Method: This was a prospective study of 25 healthy volunteers. Neck ultrasonography was performed as each volunteer swallowed 10 mL of water. The parameters studied were: diameter, anterior and lateral displacement of UES duration of UES, opening and UES displacement. Student’s t tests were applied for the statistical analysis. Results: The mean diameter of the closed UES was 0.78 ± 0.13 cm, while the mean duration of opening was 415 ± 57.66 ms, and the mean duration of displacement was 937 ± 120.98 ms. Maximum anterior and lateral displacement of the UES was 0.42 ± 0.12 cm and 0.35 ± 0.18 cm, respectively. There was a significant difference between men and women for lateral displacement of the UES (P = .04). Conclusion: This study established standards for ultrasound study of the UES during swallowing, using a non-invasive readily accessible method that may be useful for assessing swallowing disorders involving the UES (Zenker’s diverticulum, fibrosis, stricture).

Swallowing sound signal: Before and after total laryngectomy

OBJECTIVES: Comparative evaluation of swallowing function in patients treated with Supracricoid Partial Laryngectomy with CHEP reconstruction (SPL-CHEP), using Flexible Endoscopic Evaluation of Swallowing with Sensory Testing (FEESST) and videofluoroscopy. METHODS: Swallowing function was analyzed using FEESST and videofluoroscopy. Patients were endoscopically evaluated for pooling, spillage, penetration and aspiration during ingestion of different food consistencies. The laryngeal adductor reflex and laryngopharyngeal sensation were evaluated with touch and calibrated air pulses of 4, 6 and 10 mmHg. Fluoroscopic visualization was used to identify the overall efficiency and physiology of swallow. Pooling, penetration and aspiration were noted. RESULTS: Forty-four patients were included. Mean age was 60.7 years. All patients were evaluated using both methods. Most (56.8%) were stage III on pathological examination. Only one arytenoid was preserved in 61.4%. Mean time to decannulation and oral feeding were 8.7 and 8.2 weeks, respectively. Complete airway closure during swallowing was observed in 86.4%. Arytenoid reflex after air pulse of 4, 6 and 10 mmHg was presented respectively in 4.5%, 18.2% and 29.5%. FEESST with all consistencies revealed pooling in 81.8%, penetration in 18.2%, but no aspiration among all patients. Eight patients (18.1%) had silent aspiration seen on videofluoroscopy. CONCLUSIONS: Swallowing disorders are frequently observed in patients after SPL-CHEP. Videofluoroscopy, better than FEESST, is important to diagnose silent aspiration. FEESST gives information about laryngeal sensitivity due to anatomical and functional changes. Both exams are important for re-education and rehabilitation of swallowing after partial laryngeal surgery.

Multiresolution for the detection of xiphoidal sounds in noisy medical audio signals

In this paper a method we have developed in order to detect particular events (xiphoidal sounds) in swallowing audio signals is presented. The difficulty of the problem comes from the noisy nature of our medical audio signals, due to biological and environmental reasons. Besides, xiphoidal sounds have a highly nonstationary behaviour that makes conventional analysis methods such as Fourier transform or parametric model based methods nonsuitable. Thus, the detection method we have developed is based on a wavelet multiresolution analysis of the signal which is a powerful concept particularly adapted to signals dominated by transient behaviour or discontinuities. The decomposition levels of signals that comprise significant information are automatically selected and a multicriteria decision function is used to detect xiphoidal sounds among selected peaks.