Retinal vascular abnormalities in the far periphery of pathologic myopic eyes imaged by ultra wide-field fluorescein angiography

Abstract

 

Purpose

 

We have previously found that the retinal vasculature in the posterior fundus showed various abnormalities due to mechanical stretching, and have called this condition as myopic retinal vasculopathy. Recently, the imaging of far-peripheral retina is possible by using Optos 200Tx. In the present study, we examined the retinal vasculature in far periphery by using Optos in a large number of highly myopic eyes.

 

Methods

 

One hundred and forty-eight eyes (79 patients) with bilateral high myopia (myopic refractive error ≥-8.00 diopters (D) or axial length >26.5 mm) were studied. For the control, 42 emmetropic eyes which were the fellow eyes of aged-related macular degeneration or central serous chorioretinopathy were examined. The patients who had systemic conditions, such as diabetes of hypertension were excluded. Venous phase of the fluorescein angiographic images taken by Optos 200Tx were analyzed. To exclude the influence of eyelid, we evaluated the nasal and temporal peripheral retina.

 

Results

 

Highly myopic eyes showed various abnormalities in retinal vasculature in the far periphery by Optos. Retinal capillary teleangiectasia was seen in 86.1%, the microaneurysms were seen in 55.4%, the dye leakage from microaneurysms or retinal capillaries was seen in 30.4%, and the avascular area was seen in 83.8%. Teleangiectasia and the microaneurysms were also seen in far-peripheral retina in emmetropic eyes (80.0%, 35.6%). However, the avascular area or the dye leakage was never seen in emmetropic eyes. Even in highly myopic eyes, the avascular area was seen significantly more frequently in eyes whose axial length were > 30 mm than the eyes whose axial length was ≤ 30mm (P < 0.05).

 

Conclusions

 

Various retinal vascular abnormalities are observed in the far periphery by using Optos. These changes were more severe and exaggerated in eyes with pathologic myopia compared to emmetropic eyes, and retinal avascular area was seen only in highly myopic eyes. Mechanical expansion of the equator of the eye might be a cause for retinal vascular alterations in eyes with pathologic myopia.

 

Keywords: 688 retina • 605 myopia • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)