[Thermal irritation of the organ of equilibrium by means of heat radiation (NIR)].
OBJECTIVE
Convection and conduction are the main factors involved in caloric response. Heat radiation has also been discussed as an important factor. The present work tests whether heat radiation is an essential part of the caloric response and whether caloric irritation of the semicircular canals is possible using two sources with a different near infrared (NIR) spectrum. In addition, we tested whether it is possible to induce a detectable nystagmus reaction using either NIR-radiation sources.


RESULTS
NIR is able to penetrate bone tissue. The temperature elevation in dry and wet bones was almost immediately registered. With high optical power, specific temperature maxima could be seen by focal and selective broad spectrum and monochromatic NIR irritation of the three semicircular canals. Nystagmus could be generated after using both NIR emission sources in five probands.


CONCLUSIONS
NIR generates temperature differences and nystagmus. By using a broad scale as well as a monochromatic NIR-emission source, it is possible to generate a nystagmus. The procedure of NIR-irritation occurs without physical contact, is painless and quiet.
Walther
L E
LE
Universitäts-HNO-Klinik, Friedrich-Schiller-Universität Jena. lwalther@ukaachen.de
Scheibe
A
A
Schmidt
W-D
WD
Römhild
D
D
Fassler
D
D
Gudziol
H
H
Beleites
E
E
D000818:Animals; D001831:Body Temperature / Q000502:physiology / Q000528:radiation effects; D002150:Caloric Tests / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D006358:Hot Temperature / Q000009:adverse effects*; D007259:Infrared Rays; D009759:Nystagmus, Pathologic / Q000503:physiopathology; D009760:Nystagmus, Physiologic / Q000502:physiology* / Q000528:radiation effects*; D011817:Rabbits; D011829:Radiation Dosage; D014722:Vestibule, Labyrinth / Q000502:physiology* / Q000528:radiation effects*