Markus Hess

Secretion of salivary immunoglobulin A in relation to age, saliva flow, mood states, secretion of albumin, cortisol, and catecholamines in saliva.

Salivary immunoglobulin A (IgA) is one characteristic humoral factor of the local immune system in the upper respiratory tract. Epidemiological studies emphasize the importance of secretory IgA in the protection from infections of the upper respiratory tract. However, due to high interindividual variability of secretion of salivary IgA, it remains difficult to define normal ranges. This series of studies focused on identification of factors influencing basal secretion of salivary IgA. The results indicate a significant relationship between age and salivary IgA concentration. Children below 7 years have lower salivary IgA concentration than children above 7 years or adults. Furthermore, a significant inverse relationship between saliva flow and salivary IgA concentration was found. Gender, mood states, salivary albumin, salivary catecholamines, and salivary cortisol were not associated with salivary IgA. It can be concluded that for defining normal ranges of salivary IgA, age and saliva flow have to be considered.

Investigation of vocal fold impact stress in human subjects

The primary purpose of the study was to explore a methodology for measuring vocal fold impact stress (SI) in awake humans, and to provide information about the general magnitude of SIs that may occur at the midpoint of the membranous vocal folds during phonation. A secondary purpose was to examine the potential use of the electroglottographic closed quotient (EGG CQ) to indirectly reflect SI. Seven male and 13 female adults were enrolled as subjects, of whom 18 had normal larynges and normal voices, 1 had nodules, and 1 had vocal fold paresis and bowing. Subjects attempted to produce 3 different voice types (pressed, normal, breathy), at 3 different pitches (low, medium, high) and 3 different loudness levels (quiet, medium, loud). For a first set of trials, only EGG data were collected. For a second set, a sensor was also introduced to the midmembranous glottis for the collection of SI data. The primary findings were that (1) endolaryngeal sensor placement was achieved during phonation trials for 17 of 20 subjects; however, grossly consistent anteroposterior positioning was accomplished, and analyzable data were obtained, for only 7 subjects; (2) SIs ranged from less than 1 kPa to about 3 kPa for those 7 subjects; and (3) no relation was detected between simultaneous CQs and SIs for individual data, although a relation was reported in a prior canine study. One possible reason for the failure to show such a relation in the present study was subtle variations in vertical as well as anteroposterior positioning of the sensor during the trials. Future studies should focus on developing a methodology for ensuring invariant 3-dimensional sensor positioning between the membranous folds, so that the stability of both SI and simultaneous CQ data can be improved.

Endolaryngeal contact pressures

In this work, we present a new method for in vivo endolaryngeal contact pressure measurement with a miniature pressure transducer. Using this methodology, contact pressures can be measured during videoendoscopy at different locations between the artyenoids and also at various locations along the membranous vocal folds. Twenty adults with organic and functional voice disorders and two vocally healthy adults participated as subjects. Endolaryngeal contact pressure measures were made during a series of phonatory tasks varying pitch, loudness, and phonatory onset and offset. Measures were also made during nonphonatory tasks, including throat clearing, coughing, Valsalva maneuvres, and gagging. The most remarkable findings were: (1) interarytenoid contact pressures were considerably greater than intraglottal contact pressures; (2) interarytenoid contact pressures were greater for lower than higher pitches; (3) both interarytenoid and intraglottal contact pressures were remarkably large during hard glottal attack; and (4) overall, the largest endolaryngeal pressures were recorded between the arytenoids, during a thoracic fixation maneuver and during gag reflex.

Correspondence of electroglottographic closed quotient to vocal fold impact stress in excised canine larynges

The purpose of this study was to explore the possible use of the electroglottographic closed quotient (EGG CQ) as a noninvasive estimate of vocal fold impact stress (SI). Two excised canine larynges were used. Each larynx was mounted and vocal fold oscillation was induced using a humidified air source. Twenty-seven experimental trials were conducted for each larynx. Trials involved variations in vocal process gap, vocal fold elongation, and subglottic pressure. Simultaneous measures were made of vocal fold SI at the midpoint of the membranous vocal folds, and EGG CQ (dimensionless ratio). The results indicated that when threshold and saturation effects were excluded, the SI and the CQ were strongly related (linear correlation r = .83 and .96 for the two individual larynges, and .81 for the combined data). Within the region of linear relation, an increase of.15 in the CQ corresponded to about 1 kPa increase in SI for the combined data. Discussion focuses on possible clinical implications and the likely reasons for threshold and saturation phenomena.

Hearing screening in at-risk neonate cohort

OBJECTIVE This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population. DESIGN From 1990 to 1997, 942 neonates were screened with transient evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA). RESULTS 835 Infants passed the primary screen for both ears, 57 for one ear, adding up to 94.7%. Seventeen infants (1.9%) were lost to follow-up. In thirteen infants (1.4%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 820 children receiving aminoglycosides, only one presented no other risk factors. In 11 of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss. CONCLUSIONS From our data, aminoglycosides seem not to be an important risk factor for communication related hearing impairment, when serum levels are continuously monitored, as occurred in our cohort. After adjustment for other risk factors, birth weight between 1000 and 1500 g and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a Neonatal Intensive Care Unit (NICU) reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of 13 hearing impaired infants) demands further monitoring, close follow-up, counselling and adequate treatment.

Measurements of Vocal Fold Elasticity Using the Linear Skin Rheometer

Objective: The linear skin rheometer (LSR), which measures skin visco-elasticity, was adapted for measurements of vocal fold properties. A series of studies was performed on animal and human excised larynges to determine if the LSR technique can be applied to the vocal fold. Methods: In excised larynges, small patches of mucosa were driven sinusoidally at 0.3 Hz over distances of 1–2 mm using a small probe. Forces in the order of 1 g equivalent gave optimal measurements. Stiffness and viscosity values were derived from stress/strain data. Results: The instrument was able to measure the visco-elasticity of the tissue in a repeatable manner and it could detect areas where the tissue was artificially stiffened. Two-dimensional maps of the mechanical properties of the laryngeal mucosa were obtained showing local variations in elasticity both parallel and perpendicular to the vocal fold edge. Initial studies were undertaken using animal tissue; more recently, the LSR has been successfully used to obtain similar data from human tissue. Conclusion: The LSR was been demonstrated to be capable of measuring the elastic properties of the vocal fold in a repeatable and reliable manner. Further studies will now be undertaken to obtain data from a larger sample of human tissue.

Vocal fold scars: current concepts and future directions. Consensus report of the phonosurgery committee of the European laryngological society

Scarring of the vocal folds leads to a deterioration of the highly complex micro-structure with consecutively impaired vibratory pattern and glottic insufficiency. The resulting dysphonia is predominantly characterized by a reduced vocal capacity. Despite the considerable progress in understanding of the underlying pathophysiology, the treatment of scarred vocal folds is still an unresolved chapter in laryngology and phonosurgery. Essential for a successful treatment is an individual, multi-dimensional concept that comprises the whole armamentarium of surgical and non-surgical (i.p. voice therapy) modalities. An ideal approach would be to soften the scar, because the reduced pliability and consequently the increased vibratory rigidity impede the easiness of vibration. The chosen phonosurgical method is determined by the main clinical feature: Medialization techniques for the treatment of glottic gap, or epithelium freeing techniques for improvement of vibration characteristics often combined with injection augmentation or implantation. In severe cases, buccal mucosa grafting can be an option. New developments, include treatment with anxiolytic lasers, laser technology with ultrafine excision/ablation properties avoiding coagulation (Picosecond infrared laser, PIRL), or techniques of tissue engineering. However, despite the promising results by in vitro experiments, animal studies and first clinical trials, the step into clinical routine application has yet to be taken.

Qualitative and quantitative analysis of voice onset by means of a multidimensional voice analysis system (MVAS) using high-speed imaging

High-speed filming is one of the most informative methods for assessing voice physiology data. Tracing high-speed images of the glottis provides quantitative parameters such as the glottal area and the glottal width function. By way of example, a number of studies are discussed which extract quantitative data from high-speed images showing voice onsets. Furthermore, a new computer system (MVAS; multi-dimensional voice analysis system) is presented that synchronously displays a laryngoscopic high-speed film, the electroglottographical signal, and several acoustic analyses of the recorded voice sample. The automatic measurement of glottal width and glottal area from the laryngoscopic images is also provided. Looking at former studies and our analyses of voice onsets reveals a tremendous intersubject and even intrasubject variability (different prephonatory closure, different time span until full amplitude is reached, different open quotient).

Wird die Diagnose bei persistierenden kindlichen Hörstörungen immer noch zu spät gestellt

ZusammenfassungDas Deutsche Zentralregister (DZH) für kindliche Hörstörungen hat seit 1994 Patientendatensätze von 1500 Kindern erfaßt und kann mittlerweile u.a. Aussagen und Ergebnisse zum Diagnosezeitpunkt persistierender kindlicher Hörstörungen in der Bundesrepublik Deutschland vorlegen. Nach wie vor ist das mittlere Alter bei der Diagnose persistierender kindlicher Hörstörungen sehr hoch. Das Diagnosealter korreliert stark mit dem Grad der Hörstörung, d.h. an Taubheit grenzende und hochgradige Hörstörungen werden deutlich früher diagnostiziert als leichte und mittlere. So werden leichte Hörstörungen im Durchschnitt erst mit 6;2 Jahren diagnostiziert, mittlere mit 4;4 Jahren, hochgradige mit 2;5 Jahren und an Taubheit grenzende mit 1;9 Jahren. Dies entspricht den Ergebnissen bereits vorliegender regionaler deutscher Studien [1–2]. Aus anderen europäischen Länderen sind zumindest regional deutlich frühere Diagnosezeitpunkte bekannt [3–5]. Bei 36% der im DZH erfaßten Kinder liegt zwischen dem ersten Verdacht auf Vorliegen einer persistierenden kindlichen Hörstörung und der Sicherstellung der Diagnose ein Jahr und mehr.SummarySince 1994, the German Registry for Hearing Loss in Children has registered data of 1500 children and by now can present results concerning the age at diagnosis of permanent hearing loss in children in Germany. The mean age at diagnosis is still very high. There is a strong correlation between age at diagnosis and degree of hearing loss, i.e., severe and profound hearing loss, is diagnosed distinctly earlier than mild and moderate hearing loss. On average, mild hearing loss is diagnosed with 6.2 years, moderate h.l. with 4.4 years, severe hearing loss with 2.5 years and profound hearing loss with 1.9 years. This corresponds with the results of regional German studies. At least regionally, in other European countries the age at diagnosis is known to be distinctly lower. In 36% of the children registered in Germany the delay between first suspicion and diagnosis of permanent hearing loss is 1 year or more.

In vivo measurement of the elastic properties of the human vocal fold

The ability to measure the biomechanical properties of the vocal fold in vivo is both an aid to diagnosis and enhances our knowledge of how the vocal folds operate. This paper details a new instrument that is capable of taking readings of the spring rate of the vocal fold in a repeatable manner. We also present three sets of readings taken from two volunteer patients. Patient 1 was suffering from polyp growth, and the data presented are taken from both the damaged vocal fold and the healthy vocal fold. The third set of readings was obtained from a similar volunteer and taken from a healthy vocal fold. It can be seen that the data obtained from the healthy vocal folds are similar and that the data obtained from the diseased vocal fold is at variance.