The Dry Eye Zone

Rebecca's Blog


Study: Dry eye characteristics of LASIK candidates in Russia

So this study looked at dry eye in people getting evaluated for potential LASIK. I found many things about this interesting, including:

  • They classified dry eye both on the basis of OSDI and on DEWS classification.

  • 36% had signs of tear deficiency… and the average age was 30 years old.

  • Symptom based dry eye assessment was much higher than clinical sign-based

  • Only half of the patients whose dry eye warranted treatment were getting treatment

Most of all… I wonder how many of the folks with dry eye ended up getting LASIK.



To assess the prevalence and severity of dry eye syndrome (DES) in patients with myopia being evaluated for laser in situ keratomileusis (LASIK).


The prospective, non-interventional, cross-sectional study involving 9 Russian ophthalmic centers included 400 patients with myopia (aged 29.7 years in average). Among them, 145 (36.2%) wore contact lenses, and 81 (20.2%) used locally administered drugs for treatment of DES. The examination included Shirmer I test, tear film break-up test (TBUT), staining with lissamine green and fluorescein (Oxford scale), Ocular Surface Disease Index (OSDI) questionnaire, and classification of the disease according to dry eye workshop (DEWS).


Average Shirmer test result was 15.2 mm; 36.5% of patients had signs of tear deficiency (Shirmer test ≤10 mm). Average TBUT was 11.7 seconds; the tear film of 10.1% of patients was unstable (TBUT <5 seconds). Lissamine green staining was classified as insignificant or higher (degree ≥I) in 62.3% of patients and mild or higher (degree ≥II) - in 22.8%. Mean score of the OSDI questionnaire was 20.4 indicating mild vision impairment. Dry eye severity according to DEWS classification was mild/episodic in 66.2%, moderate - in 29.5%, and severe - in 4.3% of patients. No clear correlation was evident between the Schirmer/TBUT scores and the lissamine green/OSDI scores.


The prevalence of dry eye in this population was estimated at approximately 10% to 40% (based on clinical signs) and 40% to 55% (based on symptoms); dry-eye severity was predominantly mild/episodic. The proportion of patients requiring dry-eye therapy (based on OSDI and DEWS severity findings) was almost 2 times higher than the proportion receiving treatment.

[Prevalence and severity of dry eye syndrome in myopic candidates for laser in situ keratomileusis]. (Maychuk, Vestnik Oftalmologi, 2019.)