title: Thermal effects of cold light sources used in otologic surgery.
abstract: The objective of this study was to investigate the thermal effects of cold light sources and endoscopes on the inner ear. 25 male guinea pigs were assigned equally to five groups (1: Halogen-1 min, 2: Halogen-5 min, 3: Xenon-1 min, 4: Xenon-5 min, 5: Controls). After both bullae of the guinea pigs were opened, light sources and endoscopes were positioned in the middle ears of the first four groups for specific time periods. DPOAE and ABR tests were conducted on all animals at the beginning of the study, at the end of surgery, and 2 h after surgery. The temperatures of cold light sources were measured by a thermocouple thermometer, and the surface temperatures of the endoscopes were measured by an infrared thermometer. DPOAE and ABR measurements performed right after and 2 h after surgery in group 1, 2, 3, and 5 did not reveal any significant difference. In group 4, DPOAE values were significantly lower and ABR threshold values were significantly higher than those in the other groups, right after and 2 h after surgery. Thermocouple thermometer readings showed that, after the first minute, the Xenon light source generated significantly more temperature rise than the Halogen light source. The surface temperatures of all endoscopes returned to normal approximately 1 min after light sources were turned off. Our study demonstrated that when an endoscope using a Xenon light source was applied to the middle ear for a specific time periods, inner ear functions deteriorated, as reflected by audiologic tests.
authors.affiliation: Department of Otorhinolaryngology, Bezmialem Vakif University, Fatih, Istanbul, Turkey.
authors.forename: Fadlullah
authors.initials: F
authors.lastname: Aksoy
authors.forename: Remzi
authors.initials: R
authors.lastname: Dogan
authors.forename: Orhan
authors.initials: O
authors.lastname: Ozturan
authors.forename: Sabri Baki
authors.initials: SB
authors.lastname: Eren
authors.forename: Bayram
authors.initials: B
authors.lastname: Veyseller
authors.forename: Ozge
authors.initials: O
authors.lastname: Gedik
mesh_terms: D000818:Animals; D003080:Cold Temperature; D004195:Disease Models, Animal; D004432:Ear, Middle / Q000601:surgery*; D019723:Endoscopes; D006168:Guinea Pigs; D007259:Infrared Rays; D008029:Lighting; D008297:Male; D055100:Optical Fibers; D013506:Otologic Surgical Procedures / Q000379:methods*