Laser Raman spectroscopy of the lens in situ, measured in an anesthetized rabbit

Abstract
We have obtained the first Raman spectrum from the lens of a live animal. A laser beam (514.5 nm; 15 mW) was directed into the eye of an anesthetized rabbit at 60° from the visual axis and Raman emission was collected at 90° from the incident beam. The power density at the retina was estimated at 0.5 W/cm2. The entire scattering column in the lens can be imaged on the entrance slit of a spectrometer with so little distortion that Raman “optical dissection” analysis (Askren, Yu and Kuck (1979) Exp. Eye Res. 29_, 647) can be performed on the in situ lens. The advantages of multichannel detectors over photomultiplier tubes with respect to in situ measurements are discussed.