EVALUATION BY SLIT-LAMP TECHNIQUES 193 Figure 16. Posterior capsular and subcapsular cataract, rabbit Table V Slit-Lamp Examination of the Lens Anterior capsule Grade I Faint precipitates on the anterior lens capsule, usu- ally localized in I or 2 areas Grade 2 Precipitates around the entire circumference of the anterior capsule no vacuoles present Grade 3 Precipitates around the entire circumference of the anterior lens capsule localization of precipitates in the central portion of the capsule forming ring or semiring deposits (corresponds to the size of the normal pupil) vacuoles present Grade 4 Complete clouding of the anterior capsule by pre- cipitates numerous vacuoles present the lens cortex and posterior capsule usually may not be observed due to the clouding CONCLUSION In conclusion, it has been found that slit-lamp examination of experimental animal eyes is a valuable tool for the ophthalmic investigator. Various agent. s, administered either topically to the animal eye, or even systemic compound administration, can cause significant ocular pathology. Since many of these changes are too subtle to be detected by macroscopic examination, slit-lamp

194 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table VI Ocular Changes Graded with Aid of Slit Lamp during Topical Ocular Exposure to Various Shampoo Formulations Treatment • Observation Period Cornea Fluorescein Staining Flare Iritis Opacity Area Intensity Area Shampoo A 0 0 • (0/6) c 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) i 0.1 (1/6) 0.5 (3/6) 1.6 (6/6) 2.1 (6/6) 1.3 (6/6) 9..1 (6/6) oe4 0 (0/6) 0 (0/6) 0.5 (3/6) 1.0(3/6) 0.3 (2/6) 0.3 (2/6) Shampoo B Shampoo C Control 0 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 1 0(0/6) 0.1 (1/6) 0.3(•/•) 0.5(•./6) 0.8(4/6) 1.0(4/•) 24 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) i 0.5 (3/6) 1.0 (6/6) 3.2 (6/6) 4.0 (6/6) 1.8 (6/6) 2.4(6/c) 24 0.1 (1/6) 0(0/6) 2.1 (5/6) 3.1 (5/6) 1.3 (4/6) 1.5 (4/6) 0 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 1 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 24 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0/6) 0 (0,/6) 1:oe dilutions of three commercially available shampoos were instilled into 6 rabbit eyes. The eyes xvere observed at 1 and 24 hours after treatment. Mean score. The score or each parameter was graded by scales as indicated in this mono- graph. For each time period, the scores xvere totaled and divided by the number of eyes for the mean score. Incidence. Number of eyes demonstrating the ocular change/number of eyes tested. examinations are no•v used as an integral, routine part of the evaluation o[ ne•v drug entities in animals which are ultimately designed for ocular use. Since many cosmetics and other •ormuIations are now also evaluated for ocu- lar irritation, we •eel that slit-lamp examinations may be useful for the study of the toxicity potential ooe these periocular applied agents. Although photographic recordings of ocular changes are useful tools to the investigator, •ve have found that simple reproducible numerical grading scales may be easily established to document slit-lamp examinations. However, we have found that stereophotographs are an essential aid for teaching purposes wherein several investigators are called upon to grade pathologie ehanges in experimental animals. Without stereophotographs, the developer o• a subjec- tive grading scale must spend many hours •vith each investigator to enable combinability of results. Compared to this alternative, a collection ooe stereo- photographs representative of the various grades of a specific condition may be projected for a group and subsequently viewed individually as necessary, even during actual examination procedures. These techniques of teaching h ave greatly reduced investi gator-to-investigator variabilities.