Posters

Epidemiology of the 'disproportionate' eyes in Azerbaijan

Poster Details

First Author: L.Bilandarli AZERBAIJAN

Co Author(s):    B. Babayeva              

Abstract Details

Purpose:

Despite the improvements in the technique of cataract surgery, the development and introduction of new IOLs modifications to ophthalmic practice, the achievement of high functional results often leaves much to be desired. Miscalculations of IOL power are still high on the list of reasons for poor performance of postoperative refraction. Today, mixed formulas are used in preference to the calculation of the IOL in different ranges of axial length values. However, this is true only under the condition of the proportionality in the size of the corneal segment and axial length of the eye. Otherwise, the probability of rough refractive errors is not ruled out. According to the mentioned above we consider the research of the frequency of 'disproportionate ' eyes occurrence in Azerbaijan to be current.

Setting:

National Centre of Ophthalmology named after academician Z. Aliyeva, Baku, Azerbaijan.

Methods:

The study involved 110 patients (200 eyes) aged from 6 to 86 years, including 65 women and 55 men. To assess the degree of proportionality of the eyes, the comparison was made between the diameter of the corneal segment, calculated according to the Holladay formula (AG = 12,5 L/23,45, where AG - base diameter of the corneal segment in mm, L - axial length of the eye in mm) and obtained by adding 1 mm to the value of «white-to-white». Deviation of the measured diameter of the corneal segment from the value calculated by the Holladay formula for 0,5 mm is regarded as the cases of disproportionality of the corneal segment and axial length of the eye. The measurements of a horizontal diameter of the cornea («white-to-white») and the axial length were performed by means of IOL Master 500 (Carl Zeiss, Germany). All values of the axial length were conditionally divided into four ranges: L < 22 mm, 22 < L < 24,5 mm; 24,5 < L < 26 mm; L > 26 mm.

Results:

In the general group, 'disproportionate' eyes was 56% (112 eyes), within the range of values for L < 22 mm - 96% (48 eyes), while in all cases WTW+1 value was more than the AG; in a second range - 40% (20 eyes), while in most cases WTW+1 value was more than AG (19:1); in a third range - 38% (19 eyes), while in most cases WTW+1 value was less than the AG (3:16); within the range of values for L > 26 mm - 50% (25 eyes), while in all cases the value WTW+1 was less than AG. It is also important to note that the difference in the values of the diameter of the corneal segment obtained by the two methods was up to 2,6 mm.

Conclusions:

A rather high percentage (56%) of cases of the 'disproportionate' eyes among the population of Azerbaijan, consequently, a high probability of insufficiently precise calculation of IOLs with a variation of the magnitude of refractive error in the range from 0,5 to 2,5 diopters were found under the results of the clinical research. FINANCIAL INTEREST: NONE