Retinal vein occlusion (RVO) is the most common retinal vascular disease, and its pathogenesis is still not completely clear because of a variety of factors and related systemic diseases involved, such as hypertension retinal arteriosclerosis, increased blood viscosity, various coagulation factors, primary open-angle and chronic open-angle glaucoma[7], atrial fibrillation (AF) [8], and a low level of HDL-C [9–11].
The etiologies of elderly patients and younger patients are different. The etiologies reported in young patients could be related to coagulation disorders, homocysteinemia due to genetic disorders[2], hypercoagulable state after COVID-19 infection[12, 13], neonatal cerebral infarction[14], children with high ocular pressure[15], retinal venous inflammation and central serous chorioretinopathy [3, 4].
After detailed medical history inquiry and laboratory test workup, no clear risk factors or pathogenesis factors other than high levels of Lp(a) were found in the patient in this report. Hyperlipidemia has been reported to be associated with CRVO [3, 16, 17]. Lp(a) is a complex with a stable plasma level in general, and its levels are primarily regulated by genetic factors. In addition, multiple environmental factors, such as ethnicity, age, and sex, also influence its levels in the plasma [18, 19]. In view of the fact that the patient in this case had no abnormalities in the clinical laboratory test except Lp (a), which could be due to hereditary high levels of Lp (a). It is essential to screen parents or siblings for plasma Lp (a) when patients are found to have a high level of Lp (a), which can help the identification of patients with potentially Lp (a)-associated RVO. Lp (a) may promote the expression of proinflammatory cytokines and the invasion of inflammatory cells into the arterial wall[19]. In addition to elevated Lp(a), inflammatory factors can also disrupt the normal structure and function of endothelial cells, causing vascular problems[19, 20].
Corticosteroids and anti-vascular endothelial growth factor (anti-VEGF) drugs can be applied alone or in combination to treat CRVO and improve venous engorgement and visual symptoms.
When corticosteroids or anti-VEGF agents are used alone in the treatment of CRVO, there is no significant difference in BCVA and central retinal thickness (CRT) [21]. Additionally, while there is a report showing that corticosteroids have better retinal perfusion than anti-VEGF[22], some reports also document that anti-VEGF agents are more effective than corticosteroids in improving BCVA of eyes with RVO [23, 24].
Compared to corticosteroids or anti-VEGF treatment alone, the combination of corticosteroids and anti-VEGF treatment resulted in better improvement of BCVA and prognosis, reduced risks of IOP elevation, fewer intraocular injections, and a longer mean time for anti-VEGF reinjection [25, 26].
In terms of serious adverse effects, there were no significant differences between corticosteroid implants and anti-VEGF implants[24]. Compared to anti-VEGF agents, corticosteroid implantation shows a higher risk of IOP elevation and cataracts but fewer injections[23].