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P H Van De Heyning

Publications and source records attributed to P H Van De Heyning.

7 recordsLinked to original sources
PubMed2006

Validity of a new feedback method for the VEMP test.

CONCLUSIONS: We used a feedback method, based on a blood pressure manometer with inflatable cuff, to control the sternocleidomastoid muscle (SCM) contraction. To obtain comparable left-right VEMP responses, it is necessary (1) to determine which cuff pressures on both sides yield identical mean rectified voltage (MRV) values of the SCM contraction and (2) to apply these cuff pressures during the VEMP test. OBJECTIVE: To investigate the effect of the SCM muscle contraction variability on the VEMP variables when applying the feedback method. MATERIALS AND METHODS: Subjects pushed with their jaw against the hand-held inflated cuff to generate cuff pressures of subsequently 30, 40 and 50 mmHg during a MRV and VEMP measurement. RESULTS: When analyzing the relationship between the applied cuff pressures and the MRV values/VEMP amplitudes, we showed that (1) there was a linear relationship, (2) there was no side effect and (3) there was an interaction effect between 'side' and 'subject'. There was neither a side effect, nor an effect of the applied cuff pressure when considering the p13 latencies. As for the n23 values, there was no side effect but there was a significant difference when comparing the n23 latencies at cuff pressures of 30 vs 40 mmHg/50 mmHg.

Acoustic Stimulation↗
PubMed2002

Otosclerosis: a genetically heterogeneous disease involving at least three different genes.

Otosclerosis is caused by abnormal bone homeostasis of the otic capsule, resulting in hearing impairment in 0.3%-0.4% of the white population. The etiology of the disease remains unclear and environmental as well as genetic factors have been implicated. We localized the first autosomal-dominant locus to chromosome 15 in 1998 (OTSC1) in an Indian family and, recently, we reported the localization of a second gene for otosclerosis to a 16 cM interval on chromosome 7q (OTSC2). In this study, we recruited and analyzed nine additional families (seven Belgian and two Dutch families with 53 affected and 20 unaffected subjects) to investigate the importance of these loci in autosomal-dominant otosclerosis. We completed linkage analysis with three microsatellite markers of chromosome 15 (D15S652, D15S1004, D15S657) and five microsatellite markers of chromosome 7 (D7S495, D7S2560, D7S684, D7S2513, D7S2426). In two families, results compatible with linkage to OTSC2 were found, but in the seven remaining families OTSC1 and OTSC2 were excluded. Heterogeneity testing provided significant evidence for genetic heterogeneity, with an estimated 25% of families linked to OTSC2. These results indicate that, besides OTSC1 and OTSC2, there must be at least one additional otosclerosis locus.

Chromosomes, Human, Pair 15↗
PubMed2002

Interpretation of pure-tone thresholds in sensorineural hearing loss (SNHL): a review of measurement variability and age-specific references.

When assessing a patient with a sensorineural hearing impairment, the most simple and most widely available technical investigation is pure-tone audiometry. Although it is a subjective measure, the test is very reliable if the patient is cooperative. In this paper we review standards and test-retest reliability for pure-tone audiometry. A pure-tone threshold measurement at a single frequency has a chance of 90% to be repeated between -10 dB and +10 dB compared to the first measurement, assuming no real change in hearing thresholds has occurred. It is also of great importance to use correct gender- and age-specific reference values when interpreting pure-tone threshold measurements. Several large-scale epidemiological studies have been conducted during recent years, and have provided us with reliable gender- and age-specific references. A method to take into account the age-related deterioration is presented. In this method, Z-score audiograms represent traditional thresholds in an age- and gender-independent way. At each frequency, the Z-score value is the number of standard deviation units that the threshold differs from the median value for the otologically normal population (ISO 7029).

Adult↗
PubMed2000

High resolution imaging of the mouse inner ear by microtomography: a new tool in inner ear research.

A newly developed desktop microtomograph was used to evaluate whether it is suitable for visualizing the three-dimensional (3D) morphology of the mouse inner ear (at a micrometer level) and whether it is applicable as a fast screening tool to detect hereditary abnormalities in this organ. To this end, the epistatic circler, a mutant mouse showing abnormal circling behaviour, was used as a model. The inner ears were dissected out, formaldehyde-fixed, and scanned at maximal resolution along the longitudinal axis. After segmentation, stacks of tomographic images were used for 3D reconstruction of the bony labyrinth. Finally, the obtained data were correlated with subsequent conventional histological examination. The spatial resolution (8 microm) achieved by this instrument, was found to be far superior to that obtained by conventional computer tomography (CT) and magnetic resonance (MR)-imaging equipment. The technique provides detailed tomographic images of the bony labyrinths and enables an adequate 3D reconstruction of the inner ear structures in this small mammal. In addition, it allows a screening for pathologic specimens prior to the more time- and labour-consuming histological techniques, which are still essential to gather information at a (sub)cellular level. This imaging technique can be regarded as a valuable tool in future research on hereditary inner ear abnormalities.

Animals↗
PubMed2000

Computerized electronystagmography: normative data revisited.

This study provides normative data from computerized electronystagmography (ENG) testing of 40 healthy subjects with an average age of 45 years. The clinical test protocol comprises an extensive vestibular examination with oculomotor, positional, rotary chair and caloric tests. The results show that with a computerized ENG set-up considerable variabilities of 22% for rotary chair asymmetry and 19% for caloric labyrinth asymmetry remain.

Adult↗