Posterior Segment Evaluation of Patients With SLE Using OCT and OCTA

Posterior Segment Evaluation of Patients With Systemic Lupus Erythematosus Using Optical Coherence Tomography and Optical Coherence Tomography Angiography

Aim of The Study To evaluate different structural retinal changes using OCT and OCT-A in patients with SLE ; newly diagnosed patients and patients on treatment and compare parameters with normal subjects

Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory

disease that involves different organs and systems. The heterogeneous nature of

the disease represents a great challenge in its diagnosis and management. Studies

reported that the percentage of SLE patients demonstrating ocular manifestations

can reach up to 30%.

The pathogenesis of the ocular involvement is still unclear, but immune

complex vasculopathy and inflammatory mediators might be implicated. The most

common ocular manifestation in SLE was found to be kerato-conjunctivitis

sicca(KCS) followed by retinopathy, where is the most severe manifestation was

the optic nerve involvement, which might end up with irreversible blindness while

anterior uveitis is a rare manifestation in SLE.

Retinal involvement can vary from subclinical vascular changes to vaso-

occlusive vision-threatening retinopathy. Lupus retinopathy is secondary to IgG

complex-mediated micro-angiopathy that leads to small vessels infarcts. Currently,

there is no agreement on existing biomarkers to identify SLE patients who have

subclinical retinal involvement, or to identify whether micro-vascular changes in

the retina are attributable to SLE. Lupus retinopathy is usually associated with

high disease activity especially nephritis and cerebritis.

On the other side, hydroxychloroquine,(HCQ) a cornerstone in lupus treatment, rarely causes ocular toxicity at doses of less than 6.5 mg/kg per day. Moreover, HCQ is found to be associated with retinopathy after a prolonged time of treatment (>5 years).

HCQ binds to melanin pigments in the retinal pigment epithelium (RPE). This binding may serve to concentrate the agents in the cell and contribute to their long-term effects. The classic pattern of retinal toxicity of HCQ is RPE depigmentation with foveal sparing, known as bull's-eye maculopathy. Although visual acuity in these patients seems intact, patients complain from para-central scotomas associated with reading difficulties. Besides, reduced color perception can be seen as retinopathy symptoms. That is why it is important to evaluate the eyes before starting therapy and during follow-up visits.

Modern imaging techniques have provided easier and more accurate evaluation as Optical coherence tomography (OCT) is a noninvasive imaging technology, which picks up cross-sectional pictures of the retinal layers, detect thinning of retinal nerve fiber layer and macula.

Optical coherence tomography angiography (OCTA) is a relatively new technique that allows visualization of the retina capillary bed and its subtle changes.

Inclusion Criteria:

1. Age ≥18 years old.
2. Patients with SLE diagnosed by a Rheumatologist with no ocular involvement upon clinical examination

Exclusion Criteria:

1. Patients with history of intraocular surgery as cataract surgery retinal detachment surgery and anti-glaucoma surgery.
2. Patients with significant media opacity as corneal opacity, cataract.
3. Patients with ocular diseases as glaucoma, uveitis.
4. Patients with any retinal affection as pathological myopia, macular hole, age related macular degeneration and retinal vascular occlusion.
5. Patients with systemic diseases as diabetes mellitus (DM), hypertension, abnormal kidney functions