Characterization of ocular gland morphology and tear composition of pinnipeds.

Objective: The importance of tear film integrity to ocular health in terrestrial mammals is well established, however, in marine mammals, the role of the tear film in protection of the ocular surface is not known. In an effort to better understand the function of tears in maintaining health of the marine mammal eye surface, we examined ocular glands of the California sea lion and began to characterize the biochemical nature of the tear film of pinnipeds.

Procedures: Glands dissected from California sea lion eyelids and adnexa were examined for gross morphology, sectioned for microscopic analysis, and stained with hematoxylin and eosin.

Inputs and outputs of the lacrimal system: review of production and evaporative loss.

Meta-analyses were carried out of studies of tear production (by fluorophotometry, tear turnover rate[TTR]) and evaporation (from capture of fluid loss from the eye). TTR was reduced in dry eye relative to normal at 9.26 +/- 5.

Effect of contact lens materials on tear physiology.

Purpose: This study measured evaporation rate, thinning characteristics, and lipid layer changes in the prelens tear film (PLTF) associated with wearing of different soft contact lens materials, in an attempt to determine the biocompatibility of the material with the PLTF.

Methods: Twenty habituated contact lens wearers wore five different soft materials in a random order on the left eye at visits separated by at least 24 h. The soft contact lens materials were polymacon (Optima 38), omafilcon A (Proclear Compatibles), phemfilcon A (DuraSoft 2), balafilcon A (PureVision), and etafilcon A (Acuvue).