The influence of high myopia and hyperopia on the retinal and the optic disc vascularization after uncomplicated phacoemulsification - preliminary report

Aim of the study
To evaluate the influence of phacoemulsification on macular and the optic disc vascularization and its association with different axial lengths, in particular high myopia and hyperopia.

Material and methods
Forty eyes of 40 patients with cataract were assessed pre-operatively and 1 month after surgery. Patients were divided into three groups: Group 1 included patients with hyperopia, Group 2 included patients with high myopia and Group 3 included healthy persons without hyperopia or myopia. Examinations included measurement of best corrected visual acuity, intraocular pressure, axial length, a slit lamp biomicroscopy and OCT angiography.

Results
The mean BCDVA significantly improved in all groups. Pre-operatively, no significant differences between the groups were present, however, post-operatively, the mean macular volume was much larger in the hyperopic and myopic groups, when compared to the normo-axial group. There was significant increase in the vessel density and length of the superficial plexus of the macula in groups 1 and 3. Deep plexus macular vessel length increased significantly in group 3. Changes in the optic disc area size, as well as Cup-to-disc ratio (C/D ratio) were insignificant. The retinal nerve fiber layer thickened postoperatively in all groups, although it was only significant in the hyperopic group. Preoperatively, the myopic group had a much thinner mean RNFL than the other groups. Radial peripapillary capillary density increased significantly in group 2 and group 3 postoperatively.

Conclusions
This study reveals retinal microvascular changes in highly myopic and hyperopic eyes, which correlates with axial length. Both axial length extremes presented a worse retinal vascular architecture, but improved after the phacoemulsification surgery in terms of vascularity.