Session Title: Imaging II
Session Date/Time: Sunday 29/09/2013 | 08:00-10:00
Paper Time: 09:36
Venue: Hall G1 (Level 2)
First Author: N.Ulyanova UKRAINE
Co Author(s): L. Venger
Purpose. To describe the spectral optical coherence tomography (SOCT) patterns of optic nerve disc and peripapillary area of retina in patients with myopia and investigate the association of morphological characteristics of optic nerve disc and degree of myopia.
Setting. Morphological features of the retina and optic nerve in combination with functional tests is extremely important for monitoring of myopia. The morphological features of macula in high axial myopia have been investigated, but the study of the state of the optic nerve is not less important in these patients.
Methods. 126 eyes of 63 patients (35 females, 28 males) age range 18-69 years old, who have been undergone spectral OCT (Soct Copernicus, Optopol) and computer campimetry (Peritest 300) were the subject of our study. Patients were subdivided into 2 groups: group A – 74 eyes (37 patients) with high axial myopia (mean spherical equivalent of eyes was -9,1D±0,03, and axial length more than 28,5 mm); group B – 52 eyes (26 patients) with low degree myopia (mean spherical equivalent of eyes was -2,5D±0,03, and axial length less than 25,5 mm). A paired t-test was performed to obtain the differences of the mean values. A p-value <0,05 was considered significant.
Results. The studies found that the area of the optic nerve in both groups did not differ significantly (р>0,05). However, expansion of blind spot was set in patients with high axial myopia. In patients of both groups noted the predominance of the vertical size of the diameter of the optic nerve above the horizontal, but to a greater extent, this difference has been expressed at high degrees of myopia. Thus, the vertical disc diameter in patients with high myopia was on average 0,09±0,01 more than horizontal. In patients with low myopia, this difference was on average 0,06± 0,01. Difference between vertical and horizontal disc diameters in patients with high myopia was on 33.3% (p <0.05) higher than in patients with low myopia. Thus, at greater length axis of the eye disc form was closer to the oval. In 83% of patients with high axial myopia by spectral OCT revealed peripapillary retinal pigment epithelium atrophy as a zone of the increased signal due to choroidal reflectance at the edge of the optic nerve and the phenomenon of peripapillary intrachoroidal cavitation as the presence of hypoechogenous areas around the major retinal vessels near the optic nerve disc.
Conclusions. The method of spectral OCT enables the evaluation of changes of optic nerve disc and peripapillary area of retina in different degrees of myopia. The main criteria for the differentiation were set the difference between vertical and horizontal diameters of the optic nerve disc, the presence of peripapillary retinal pigment epithelium atrophy and peripapillary intrachoroidal cavitation.