Abstract
Purpose :
Adaptive optics scanning light ophthalmoscope (AOSLO) is considered to be well-positioned to detect early manifestations of retinal pathology. Additionally, offsetting the confocal aperture in the AOSLO enables the blocking of specular reflection from the inner retina and the enhancement of the image contrast of the retinal structures. Our purpose was to investigate the ultrastructure of hard exudates (HEs) in patients with retinal vein occlusion (RVO) using offset pinhole AOSLO.
Methods :
Six eyes of 6 patients (2 men and 4 women; mean age, 67 years) with RVO were studied. The prototype offset pinhole AOSLO (Canon Inc., Tokyo, Japan) used in this study is capable of real-time correction of ocular aberrations during imaging, which allows a transverse resolution of approximately 3 μm (beam diameter: 6.7 mm) with pupil dilation. The pinholes were offset by 180 μm (3.75 airy disk diameter) in opposite directions in the plane horizontal to the retina. The HEs were examined by color fundus photography (CFP), and the offset pinhole AOSLO at 6 and 12 months after the onsets.
Results :
On CFP, the HEs associated with RVO were seen as yellowish cylindrical structures, which were considered to be obliquely oriented in the Henle's fiber (Fig. 1). In contrast, the offset pinhole AOSLO resolved homogenously hyperreflective crystalline units inside the cylindrical structure of the HEs (Fig. 1). The mean size of the crystalline units was 32.7 ± 2.8 μm at 6 months. Parts of the crystalline units of the HEs were longitudinally disrupted, and the unit formations of the HEs were obscured at 12 months (Fig. 1).
Conclusions :
Using offset pinhole AOSLO for eyes with RVO, the crystalline units of HEs and the longitudinal changes were observed with high contrast, which could not be elucidated by CFP.
This is a 2021 ARVO Annual Meeting abstract.