[Development and preliminary results of a chromatic illumination system for indirect ophthalmoscopes].
OBJECTIVE
Chromatic contrast is a technique used in some areas of medicine to provide better visualization of biological tissues. Based on principles of color composition, a new illumination system was constructed using colored emitting diodes to reproduce the spectral range of visible light. This technique was devised to be used in indirect ophthalmoscopes to improve the visualization of the posterior segment of the eye.


METHODS
The original illumination system of a general purpose indirect ophthalmoscope was substituted by a system of color-emitting diodes.


RESULTS
Using an electronic interface it was possible to control the intensity of the color lights and therefore generate different wavelengths in the visible spectrum of the light. Preliminary tests undertaken in a mechanical model of the human eye generated very clear and homogenous colors. However in vivo examinations with patients were performed in our laboratory at the IFSC-USP and UNIFESP, and obtained the preliminary results show the possibilities of the chromatic contrast technique, and may represent in the future a differential in the analyses of the posterior segment of the eye.


CONCLUSIONS
The use of color-emitting diodes to reproduce the spectral range of the visible light in indirect ophthalmoscopes seems to be a promising technological advance in the fundoscopy of the eye. This is an innovation that can yield better quality examinations with indirect ophthalmoscopes.
Oliveira
Thiago Bellini
TB
Universidade Federal de São Carlos, SP, Brasil. thiagobelini@hotmail.com
Trevelin
Luis Carlos
LC
Moreira
Fernando Manoel Araújo
FM
Bagnato
Vanderlei Salvador
VS
Schor
Paulo
P
Carvalho
Luis Alberto Vieira de
LA
D003116:Color; D004867:Equipment Design; D005654:Fundus Oculi; D006801:Humans; D008029:Lighting / Q000379:methods*; D019721:Ophthalmoscopes; D009887:Ophthalmoscopy / Q000379:methods*