OCT in computer users

Patients who use computers for long periods of time show a correlated pattern of corneal pachymetry and epithelial thickness, high speed spectral-domain OCT scans show. This observation allows for early detection of minor pathologic changes, according to the findings of a study presented by Argyrios Tzamalis MD at the 37th Congress of the ESCRS. “Prolonged computer use may be correlated with reduced tear break-up time (TBUT) and produce ocular surface symptoms affecting the patients’ quality of life. Epithelial thickness measurements are found to be associated with some ocular symptoms but not directly to the signs of dry eye disease,” said Dr Tzamalis, Aristotle University of Thessaloniki, Thessaloniki, Greece. The prospective, cross-sectional study involved 67 patients who reported using computer and mobile phone screens more than eight hours per day. Dr Tzamalis and his team performed three consecutive measurements with the AngioVue OCTA Imaging System (Optovue) in each of the patients’ eyes, to assess the measurement’s repeatability and evaluate correlations between epithelial thickness and tear film quality. The patients in the study had a mean age of 44.5 years and used computers for a mean 9.2 hours daily. All patients completed the Ocular Surface Disease Index (OSDI) questionnaire and also underwent TBUT testing and Schirmer testing. Patients with prior refractive surgery, contact lens use or other ocular pathology were excluded from the analysis. Dr Tzamalis noted that the mean central corneal pachymetry as measured with the device was 528.4µm and mean central epithelial thickness was 52.9µm, with no statistically significant differences between the patients’ right and left eyes (p>0.05). He added that the intraclass correlation coefficient (ICC) was found to be excellent for both central corneal pachymetry (ICC=0.99) and epithelial thickness (ICC=0.98) measurements. However, the ICCs of other regions were slightly lower, although they did not differ significantly from the central part (p>0.05). Epithelial thickness was strongly correlated with total corneal thickness in every quadrant (p<0.01). He noted that central epithelial thickness correlated significantly with reported difficulty while watching TV (r=-0.303, p=0.01) and irritation in windy weather conditions (r=-0.394, p=0.01). However, there was no significant association between corneal epithelial thickness and TBUT, Schirmer test, BCVA or total OSDI score (p>0.05). In addition, the OSDI score correlated significantly to the reported number of hours spent in front of computer screens (p-0.007) and TBUT (p=0.02) but not with Schirmer testing. The most commonly reported symptoms were light sensitivity, pain and discomfort in windy conditions, Dr Tzamalis said. Argyrios Tzamalis: argyriostzamalis@yahoo.com

Tags: dry eye, ocular surface disease, osd