ABSTRACT
Preservation of sight is the major objective of many scientific studies. Topically administered drugs effectively treat many important ocular diseases. Short-term efficacy endpoints are sometimes difficult to assess following these treatment approaches. Hence, it is important to determine whether therapeutically relevant concentrations reach the site of action, as in other regions of the body. The anterior chamber of the eye is a relatively straightforward region for sampling. Anatomically accessible by paracentesis procedures, it is possible to obtain a single sample for measurement of drug concentrations. However, challenges are encountered when time-course or steady-state data are collected. Repeat sampling of this region is not possible by conventional methods in general. Traditionally, rabbits or other mammal species have been used for the assessment of intraocular concentrations of topically administered drugs. In order to obtain time-course data in aqueous humor, many animals are required, with each time point requiring multiple individual aqueous humor samples following sacrifice. These procedures present a number of challenges to be managed.
