Abstract
Abstract: :
Purpose: To compare similarities and differences between the western lowland gorilla eye and the human eye. Methods: This study consisted of extensive bilateral eye examinations of 4 western lowland gorillas at the Dallas Zoo while under sedation. Our examination included biomicroscopy, dilated fundus examination, cycloplegic retinoscopy, Schiotz tonometry, corneal diameter and thickness measurements, A-scan and B-scan, keratometry, and lid/conjunctival cultures. Gorillas that were undergoing sedation for medical examination or transportation to other areas of the zoo were chosen for this study. Results: In our series, the mean spherical equivalent refractive error by cycloplegic retinoscopy was +1.13 sphere ± 0.64 (SD) and the mean intraocular pressure by Schiotz tonometry was 15.74 mmHg ± 2.32. The mean cup to disc ratio was found to be 0.38 ± 0.07. We determined the mean horizontal corneal diameter to be 13.13 mm ± 0.64 and the mean vertical cornea diameter to be 12.38 mm ± 0.52. By ultrasound pachymetry, we determined the mean central corneal thickness was 495 microns ± 58. By A-scan, the mean axial length was 22.47 mm ± 0.43, the mean lens thickness was 4.16 mm ± 0.35, and the mean anterior chamber depth was 4.04 mm ± 0.28. The mean keratometry reading was 44.83 diopters ± 1.82. Finally, lid/conjunctival cultures revealed Candida species (4 of 4 gorillas), Staphlococcus epidermidis (2 of 4), Staphlococcus aureus (3 of 4), Micrococcus species (2 of 4), and Staphlococcus saccharolyticus (2 of 4). Conclusions: This study suggests that western lowland gorilla eyes and human eyes share important characteristics. Recently, the techniques and equipment used for cataract surgery in humans have been employed in gorillas. The similarities between the western lowland gorilla eye and the human eye support the validity of such applications. This study represents the first "published" data on gorilla eyes.
Keywords: comparative anatomy • cornea: clinical science • anterior segment