Changes in corneal sensitivity and tear physiology after phacoemulsification

To identify any changes in corneal sensitivity and tear physiology after phacoemulsification and to evaluate the effectiveness of the use of ophthalmic lubricants.

The design of the study was longitudinal, parallel, randomised and double masked. Eighteen patients (average age 70.83 +/- 10.66 years, 7 males and 11 females) undergoing phacoemulsification were recruited and divided into three groups of six. In addition to the prednisolone acetate 1% and chloramphenicol 0.5% routinely given to patients postoperatively, the first two groups were given a tear lubricant (Refresh Soothe and Protect, Allergan Inc., Irvine, CA, USA) and saline (Chauvin Pharmaceuticals Ltd, Essex, UK), respectively, and the third was a control group and did not receive any additional eye drops. Tear production, evaporation, lipid layer interferometry and osmolarity along with corneal sensitivity were measured before and 3 days, 2 weeks, 1 month and 3 months after the surgery.

Statistically significant detrimental changes were seen in all parameters of corneal sensitivity and tear physiology immediately after phacoemulsification. Tear physiology recovered within 1 month. Corneal sensitivity did not return to normal levels in 3 months, but a trend towards full recovery was seen. Saline and the tear lubricant were not found to have an effect on the improvement of tear physiology and corneal sensitivity post-surgically.

Deterioration in corneal sensitivity and tear physiology is seen immediately after phacoemulsification. Corneal sensitivity does not return to preoperative levels until 3 months postoperatively whereas the tear functions recover within 1 month.