Effects of formalin preservation on eye lens of bogue (Boops boops): comparison of direct (post-fixation) vs ultrasound (real) measurements.

Measuring the eye lens has been a used for estimating the age of mammals, birds and fish. The purpose of this study was to describe the normal ultrasonic appearance of eye lens samples from bogue cadavers by the mean of B-mode ultrasonography. In order to minimize decomposition processes the eye lenses were extracted one at a time from the fish eyes of 26 bogue (Boops boops) cadavers and immersed in 0.9% sodium chloride solution until scanning was performed. Both the eye lens were evaluated by B-mode ultrasonography immediately after collection. After examination the 52 eye lens were formal fixed air dried and equatorial eye lens diameter was measured to the nearest millimeter using a digital vernier caliper. High resolution ultrasound equipment produced high quality images and the difference between ultrasound and after fixation measurement resulted always highly significant. This study compares the B-mode ultrasound biometric evaluation on fresh eye lens with direct physical biometric evaluation on fixed eye lens.