[Use of pharyngeal pressure measurement to localize the source of snoring].
BACKGROUND
Depending on age and gender up to 60 % of the population snore regularly. As simple snoring is more a social than a medical problem, unlike OSAS, CPAP-therapy or multilevel surgery are not appropriate therapies for snoring. But alternative therapies, such as laser-assisted uvulopalatoplasty (LAUP) or uvulopalatopharyngoplasty (UPPP) address distinct sites of the pharynx. Therefore a correct identification of the snoring-source should optimise the selection of patients and improve the outcome of therapy. As there is no commonly recommended tool for identifying the snoring-source, the use of a new technique, based on pharyngeal pressure measurement, was tested.


METHODS
25 patients with suspected OSAS had standard polysomnography recordings during two nights with esophagopharyngeal pressure measurement on the second night. The pressure probe had 5 pharyngeal and 1 esophageal transducers. The curves of the pharyngeal pressure were examined for quick pressure changes superimposed on the slow pressure-changes caused by breathing. The appearance of these quick pressure changes was documented for each transducer throughout the whole night.


RESULTS
The average (+/- SD) Apnea-Hypopnea-Index in the patients was 28.3 +/- 24.8. 17 patients (68 %) had an AHI of more than 10. All patients showed heavy snoring. 23 patients (92 %) showed a high frequency, sawtooth-pattern, superimposed on the slow breathing rhythm in at least one channel and in association with snoring. 91 % of the patients showed a sawtooth pattern in more than one channel, but the pattern was always more pronounced in one channel compared to others. The sawtooth-pattern of the highest amplitude was seen in the pressure curves from the velum in 56 % of the patients, from the tonsils in 24 %, and from the tonguebase in 12 % of the patients.


CONCLUSIONS
Quick pressure changes from distinctive pharyngeal pressure transducers during snoring are common in OSAS patients and may indicate the source of snoring. Further investigations have to show whether this assumption is correct, and whether the quick pressure changes are also apparent in simple snorers.
Dreher
A
A
HNO-Klinik der Ludwig-Maximilians-Universität, München, Germany. dreher@ithnet.com
Klemens
C
C
Patscheider
M
M
Kramer
M
M
Feucht
N
N
Schultheiss
C
C
Baker
F
F
de la Chaux
R
R
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation; D008875:Middle Aged; D018579:Patient Selection; D010614:Pharynx / Q000502:physiology*; D017286:Polysomnography; D011312:Pressure; D012891:Sleep Apnea Syndromes / Q000503:physiopathology; D012913:Snoring / Q000503:physiopathology* / Q000601:surgery; D014159:Transducers