Degenerative changes in retinal vessels. Photodocumentation with monochromatic filters
O. Kaefer
The appearance of certain ocular structure changes due to changes in
absorption, reflection, and optical transmission depends on the wavelength
of light. By means of this physical quality of the light, it is possible to
demonstrate certain parts of the fundus better than others. Several
examples described in this article demonstrate how degenerative vascular
alterations can be judged much better and more safely by use of
monochromatic light and light of varying wavelengths. Alterations of blood
vessel caliber show the most contrast in yellow-green light where there is
maximum absorption by the blood. Alterations in blood vessel wall
reflection that are invisible in white light can be demonstrated in
short-wave light and also partially in red light. Ophthalmoscopy in
connection with the xenon arc lamp as a method of examination is suprior to
photography alone.
