Effect of body position on intraocular pressure in clinically normal cats

Objectives The objective of this study was to investigate the effect of body position on intraocular pressure in clinically normal cats. Methods Sixteen clinically normal cats without any ocular abnormalities were used in this study. Cats were sequentially placed in three different recumbency positions (sternal recumbency, right lateral recumbency and dorsal position). For each of the three body positions, intraocular pressure (IOP) was recorded in the left eye using a Tono-Pen Vet tonometer (Reichert). Results Mean IOP readings in cats in the sternal recumbency, right lateral recumbency and dorsal positions were 15.6 4.1, 16.6 +/- 6.4 and 18.6 +/- 6.8 mmHg, respectively. A significant increase was observed in IOP in cats in the dorsal position compared with the IOP observed in cats in sternal recumbency (P = 0.01) and right lateral recumbency (P = 0.04). There was no significant difference between the IOP recorded in the lateral recumbency and sternal recumbency (P = 0.17) positions. Conclusions and relevance Body position has a significant effect on the IOP of cats. IOP increases when cats are placed in dorsal recumbency.