Materials and Methods: Thirty-three patients with unilateral UTRVO and 37 age-matched healthy control subjects without history of diabetes and ocular surgery were included in the study. Each patient underwent complete ocular examination including keratometry and refractive error. Axial length measurements of all subjects were obtained with A-scan biometry. A total of five successive biometric measurements were obtained. Statistical analysis was performed using Mann Whitney U test and descriptive statistics. P value less than 0.05 was considered to be statistically significant.

Results: The mean age of the patients and the subjects were 55.7 ± 3.5 years and 56.4 ± 3.1 years, respectively (p>0.05). Both control and patients did not demonstrate any inter-ocular differences either in refractive error or axial length measurements ( all p values, >0.05). The refractive error (p>0.05) and keratometry (p>0.05) of the patients was not found to be significantly different than that of healthy subjects. However, the axial length of the occluded (21.86±0.87 mm) ana non-occluded eyes (21.79±0.81 mm) of the patients with UTRVO were significantly shorter than that of normal subjects (22.92±1.14 mm) (p<0.05).

Conclusion: Axial length would be considered to be a major risk factor in the development of the upper temporal retinal branch vein occlusion if no hypertension were noted in any of the subjects. Keywords : Upper temporal retinal vein occlusion, refractive error, axial length, keratometry.