Macular microvascular alterations in adults with sickle cell anemia detected by optical coherence tomography angiography.

PURPOSE

To evaluate macular vascular density (VD) and foveal avascular zone (FAZ) alterations in adult patients with sickle cell (SC) anemia without clinical signs of retinopathy using optical coherence tomography angiography (OCTA), and to compare these findings with healthy controls.

METHODS

In this cross-sectional, comparative study, 18 right eyes from 18 adult patients with SC anemia and 25 right eyes from age- and sex-matched healthy individuals were analyzed. Those with SC disease were group 1 and healthy controls were group 2. All participants had normal fundus examination findings. OCTA imaging (RTVue-XR Avanti; Optovue Inc.) was used to measure vascular densities in the superficial capillary plexus (SCP) and deep capillary plexus (DCP), as well as FAZ dimensions, using a 3 × 3 mm macular scan. Vascular density measurements were compared across eight macular sectors. Image quality below 8/10 was excluded.

RESULTS

The mean age of group 1 was 24.73±6.60, group 2 was 23.70±3.19 (p = 0.572). The female/male ratio was 10/8 in group 1 and 12/13 in group 2 (p = 0.500). DCP vascular density was significantly reduced in all sectors in the SC anemia group compared to controls (p < 0.001). SCP vascular density was significantly lower only in the temporal region (p = 0.015). Superficial FAZ was significantly enlarged in SC anemia patients (0.45 ± 0.09 mm²) compared to controls (0.33 ± 0.07 mm², p = 0.001), while deep FAZ did not show a statistically significant difference (p = 0.145).

CONCLUSION

Sickle cell anemia is associated with substantial microvascular compromise in the deep retinal capillary plexus, even in the absence of clinical retinopathy. OCTA proves to be a sensitive, non-invasive imaging modality capable of detecting subclinical vascular changes. Early identification of these alterations may aid in the prevention of vision-threatening complications in SC anemia.