Microvascular insults experienced by young patients with sickle cell disease (SCD) may lead to long-term ischemic changes in the inner retinal layers, according to a study published in the European Journal of Ophthalmology. 

In SCD, deformed erythrocytes disrupt proper blood flow, causing vaso-occlusive crises in the retinal and choroidal vessels. These disruptive changes may lead to significant eye disease, even blindness. 

Optical coherence tomographic angiography (OCTA) is an innovative imaging technology that allows the retinal vascular anatomy to be evaluated in a comprehensive and noninvasive manner. OCTA is sometimes preferred over fluorescein angiography, which is widely considered the gold standard for visualizing retinal vasculature as the latter requires fluorescein dye and it is difficult to get cooperation from children for the procedure. 

OCTA has previously been used to identify eye vasculature damage in adult patients with SCD, but pediatric patients remain relatively less studied. The authors set out to investigate the correlation between temporal vessel density detected via OCTA and temporal macular thinning detected via OCT in children and young adults with SCD. 

Read more about SCD etiology 

Sixteen young patients with SCD (genotype HbSS) were recruited, allowing for 32 eyes to be studied. The research took place at the Hospital Professor Doutor Fernando de Fonseca in Portugal where macular OCT and OCTA scans were performed on all the participants. 

Of the 16 patients under investigation, 13 did not show signs of sickle cell retinopathy, 1 had nonproliferative sickle cell retinopathy, and 2 were diagnosed with proliferative sickle cell retinopathy. The research team also reported that outer temporal macular thinning on OCT correlated with lower outer temporal vessel density on OCTA, suggesting that microvascular insults may cause chronic ischemic changes in the inner retinal layers. 

“We are confident that OCTA will play a decisive role in sickle cell patient follow-up, with a special interest in the pediatric population, being able to detect abnormal macular thinning and flow abnormalities that are undetected by biomicroscopy,” the authors wrote. 

Reference

Monteiro C, Vivas M, Almeida J, et al. Temporal macular thinning and vessel density correlation in children and young adults with sickle cell diseaseEur J Ophthalmol. 2022;11206721221132629. doi:10.1177/11206721221132629