THE EFFECT OF Rose-k CONTACT LENS WEAR ON TEAR FILM OF KERATOCONIC PATIENTS

Abstract

Abstract

The study was designed to be case control study. It aimed to determine the effect of rigid gas permeable (Rose –k 2 menicon) lenses wear on tear film of keratoconic eyes.

The study took place at Makka Eye Complex and Al-Faysal Eye Center on January 2014 to July 2014.

One hundred and fifty patients were screened, 66.67% (100) of them were found to fulfill the criteria of selection (35.7% males and 64.3% females). Their ages ranged between 10-31 years ±4.69 (66% from 10-21 years, 34% from 21-31years with a mean of 19.7±4.69 years.

Patient's history of wearing contact lenses, general and ocular health were taken. The outer and inner eyes were examined using Keeler ophthalmoscope, corneal topography was done to determine the degree of keratoconus. The fitting of contact lenses was assessed using slit lamp and the tear film was evaluated by break-up time and Schirmer test.

The data were statistically analyzed by SPSS 18 program and represented by percentages and compared through T-2 tailed test.

The control group was selected as not wearing contact lenses and study group was selected as wearing contact lenses.

The control group was fifty, 54% were males and 46% were females. The study group was 50 patients wearing Rose K contact lenses. 88% of them wearing Rose K contact lenses from six month to one year (35.7% were males and 64.3% were females).

Eighty two percent of the patients were found to have moderate keratoconus .

The study revealed the following results:

The range of break up time test for those wearing Rose K was 4 sec to 11 sec with a mean of 6.60 sec ±1.82 and for those not wearing Rose K was 3 sec to 11 sec with a mean of 7.52 sec ±1.47.

The range of Schirmer test for those wearing Rose K was of 11 mm to 23 mm in 5 minutes with a mean of 18.66 mm ±3.28 and for those not wearing Rose K was of 8 mm to 25 mm in 5 minutes with a mean of 17.34 mm ±3.77.

T- test showed significant differences in TBUT between Rose-k Menicon wearer (case study) and non contact lenses wearer group (case control) t (-2.37) P = 0.02 males wearing rose-k lenses showed significantly higher TBUT compared to females contact lenses wearer. The results also showed significant differences between females wearing rose-k and females not waering rose-k t (-5,95) P < 0.001.

As a conclusion keratoconic patients have poor tear stability which need to be considered appropriately during management of the patients, so both systemic and ocular signs of dry eye condition should be managed prior to and during CL wear especially in severe cases. Prescribing gas permeable lenses or silicone hydrogels due to their minimal effect on the tear film is advisable.

Key word: keratoconus, Schirmer test, break-up time test.