The Dry Eye Zone

Rebecca's Blog


Dry eye after cataract surgery - two studies

#1: Incidence and pattern of dry eye after cataract surgery.

Ishrat et al, Saudi Journal of Ophthalmology, Jan-Mar 2019

This one showed higher risk of dry eye after manual small incision cataract surgery than phacoemulsification, and showed dry eye rapidly improving as time passed. I wish they had included something about the OSDI scores in the abstract though - while they measured OSDI, they didn’t present those results in this summary, so we don’t know how people felt, only how they looked.



The objectives of the study were to identify the incidence and pattern of dry eye after phacoemulsification and manual small incision cataract surgeries.


The study consisted of two groups of patients - Group 1 underwent manual small incision cataract surgery (SICS) and Group 2 underwent phacoemulsification. The dry eye-related data was collected preoperatively and at 1 week, 1 month and 3 months postoperatively. Ocular Surface Disease Index questionnaire, tear break-up time (TBUT) and Schirmer test - 1 were used to record the type of dry eye.


One hundred eyes of 96 patients, including 35 (36.5%) men and 61 (63.5%) women with the mean age of 63.1 (±8.3) years were studied. Dry eyes were found in 42% eyes (p < 0.001) of patients at 1 week follow-up. Fifteen percent and 9% of the eyes were dry at 1 month and 3 months after surgery, respectively. There were 34 (53.1%) and 8 (22.2%) dry eyes in SICS and phacoemulsification groups, respectively at one week postoperative follow-up which was a statistically significant difference.Majority of eyes (27/42, 64.3%) had mild dryness. There were significant differences in TBUT at 1 week, 1 month and 3 months postoperatively. At 1 week review, the SICS group had mean TUBT of 10.0 (±0.55) sec as compared to 13.9 (±0.70) sec in phacoemulsification group (p < 0.001).


Incidence of dry eye is higher in SICS than phacoemulsification due to tear film instability. The clinicians should be conscious about dry eye symptoms and signs in an otherwise healthy eye after cataract surgery.

#2: Tear osmolarity after cataract surgery

Elksnis et al, Journal of Current Ophthalmology, Sept 2018

I don’t know why some of these take so long to show up in my feed… I doubled back to make sure I had not seen and written about this before, and I definitely hadn’t.

Anyway, this is a good one (sort of) because it looks at cataract surgery patients who have no known dry eye or similar issues (they excluded everyone from contact lens wearers to people who use eyedrops). My only complaint is that they didn’t track symptoms. Symptom data is vital to understanding dry eye.

They compared the eye undergoing surgery to the eye that was left alone, and tracked the ups and downs till it leveled off by the end of the month. One month is a pretty short time though….



To evaluate the changes in tear film osmolarity and Schirmer I test after cataract surgery.


This single-center, prospective study included patients with no subjective complaints about dry eye disease. Patients with the following conditions were excluded: contact lens wearers, patients with diabetes, pseudoexfoliation, pterygia, and eye drops users. The eye that had not undergone surgery was considered the control group. Tear osmolarity and Schirmer I test were evaluated before surgery and during the first postoperative month.


Thirty-seven patients were enrolled in the study. Before surgery, tear osmolarity was 301.2 ± 15.09 Osm/L in the study group and 302.3 ± 14.21 mOsm/L in the control group (P = 0.2), while Schirmer I test averaged 13.4 ± 10.50 mm in the study group and 13.7 ± 10.79 mm in the control group (P = 0.6). 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 (P = 0.008). The Schirmer I test in the same morning showed an increase up to 19.9 ± 9.73 mm in the study group and to 15.7 ± 10.19 mm in the control group (P = 0.01). 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 (P = 0.013). The Schirmer I test results decreased to 15.8 ± 9.37 mm in the study group and 13.9 ± 10.19 mm in the control group (P = 0.07) one week after the surgery. One month after surgery, tear osmolarity and Schirmer I test results in the study group decreased to the control group level (P > 0.05).


The tear osmolarity results increased to the dry eye disease level in the first postoperative week. Over the course of one month, the difference in tear osmolarity and Schirmer I test values for the study and control groups leveled off.