Managing Microvascular Changes Helps Preserve Photoreceptor Integrity in Diabetic Eyes

Study explores factors most significantly associated with the length of EZ disruption.

In eyes with diabetic retinopathy (DR), the length of ellipsoid zone (EZ) disruption is associated with changes in the foveal avascular zone (FAZ) and vessel densities (VDs) of deep capillary plexus (DCP), according to a study published in Retina

Researchers included in the study 159 eyes with DR and 30 healthy control eyes that were imaged with OCT and OCT-A between June 1, 2015 and September 1, 2018. Among the patients with DR, the mean age and BMI were 57.6±10.3 years and 25.67±3.7 Kg/m2, respectively. They performed simple and multiple linear regression analysis to explore the factors most significantly associated with the length of EZ disruption.

Researchers found that the length of EZ disruption was closely associated with the FAZ area (β =0.218, P =.009), parafoveal VD of the superficial capillary plexus (SCP) (β =-0.167, P =.049), foveal VD of the deep capillary plexus (DCP) (β =-0.244, P =.003), and foveal VD of the choriocapillaris (β =-0.162, P =.036). The investigators reported an increase in the FAZ area, based on DR severity. 

“Several studies using fluorescein angiography (FA) have reported on changes in the FAZ in eyes with DR,” according the report. “Recent OCT-A studies have shed light on the enlargement of the FAZ in eyes with DR, compared [with] that in controls, consistent with our results.” 

Limitations of the study include the retrospective design, relatively small sample size, and further investigation is needed to reveal the association between EZ disruption and the choriocapillaris. 

The area of the FAZ and ischemia at the DCP may play a vital role in preserving photoreceptor integrity in eyes with DR, the study suggests. 

Reference

Kim JT, Park EJ. Correlation of photoreceptor integrity with retinal vessel density and choriocapillaris in eyes with diabetic retinopathy. Retina.Published online November 2, 2021. doi:10.1097/IAE.0000000000003343