Tear osmolarity after cataract surgery

Purpose: To evaluate the changes in tear film osmolarity and Schirmer I test after cataract surgery.Methods: This single-center, prospective study included patients with no subjective complaints about dry eye disease. Patients with the followingconditions were excluded: contact lens wearers, patients with diabetes, pseudoexfoliation, pterygia, and eye drops users. The eye that had notundergone surgery was considered the control group. Tear osmolarity and Schirmer I test were evaluated before surgery and during the firstpostoperative month.Results: Thirty-seven patients were enrolled in the study. Before surgery, tear osmolarity was 301.2±15.09 Osm/L in the study group and302.3±14.21 mOsm/L in the control group (P¼0.2), while Schirmer I test averaged 13.4±10.50 mm in the study group and 13.7±10.79 mmin the control group (P¼0.6). The next morning, the tear osmolarity decreased to<275 mOsm/L in the study group while in the control group,the value increased to 303.1 mOsm/L±13.68 (P¼0.008). The Schirmer I test in the same morning showed an increase up to 19.9±9.73 mm inthe study group and to 15.7±10.19 mm in the control group (P¼0.01). One week later, the tear osmolarity increased to 311.8±14.85 mOsm/L, while the control group averaged 301.7±11.84 mOsm/L (P¼0.013). The Schirmer I test results decreased to 15.8±9.37 mm in the studygroup and 13.9±10.19 mm in the control group (P¼0.07) one week after the surgery. One month after surgery, tear osmolarity and Schirmer Itest results in the study group decreased to the control group level (P>0.05).Conclusions: The tear osmolarity results increased to the dry eye disease level in the first postoperative week. Over the course of one month, thedifference in tear osmolarity and Schirmer I test values for the study and control groups leveled off