Retinal vascular changes during pregnancy in patients with diabetes mellitus as measured using optical coherence tomography angiography

Abstract

Purpose : To assess changes in the retinal vasculature of diabetic patients with and without diabetic retinopathy (DR) during the pre-pregnancy, antenatal and early post-partum period using a non-invasive imaging modality.

Methods : Women with pre-existing diabetes mellitus who were either planning to be or were pregnant were recruited from obstetric clinics. Fundus photography, optical coherence tomography and 3x3mm optical coherence tomography angiography (OCTA) (Triton, Topcon Corp) scans were obtained. Two independent graders analyzed two images per eye and calculated mean values for the foveal avascular zone (FAZ) area and the parafoveal vessel density (VD) in the superficial capillary plexus using Imagenet software (Topcon Corp).

Results : Seventy-two eyes from 36 patients were imaged. Of the patients who were pregnant, 41% were in first trimester, with the rest evenly split between the second and third trimesters. Most had no DR (n=43 eyes, 59.7%) and no diabetic macular edema (n=65, 90.3%). Overall, the mean FAZ area was not significantly different between various pregnancy stages (p=0.19). However, in the subgroup with no DR, FAZ area varied strongly over pregnancy status with pre-pregnant patients demonstrating significantly lower FAZ areas compared to the antenatal and post-partum groups (0.17 ± 0.02 mm², 0.37 ± 0.02 mm², 0.42 ± 0.05 mm² respectively, p=0.001) (Figure 1). No significant differences in vessel density were observed.

Conclusions : This is the first study using OCTA imaging in pregnant women with diabetes. Our results suggest this non-invasive imaging can be used to assess the effects of pregnancy on retinal vasculature and may have the potential to guide management in these complex patients.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Figure 1. The effect of pregnancy status on foveal avascular zone area in patients with and without diabetic retinopathy