People who have sickle cell can have vision problems. Blood cells that change shape, or “sickle,” can get trapped in blood vessels, blocking the blood flow. When this blockage occurs in the small blood vessels in the retina, it can cause vision problems. Sickle cell disease can promote increased blood viscosity, hypoxia, venous stasis, acidosis and inflammation associated with varied systemic and ocular complications. This most often occurs in people who have hemoglobin SC disease, a type of sickle cell disease. In some cases, this can lead to retinal detachment, which can lead to permanent vision loss.
Vaso-occlusive changes can lead to several anterior segment complications, such as conjunctival sickling, which are characterized by capillary vessel segmentation. Iris changes manifest as atrophy with or without posterior synechiae. The development of the iris neovascularization could lead to secondary glaucoma, and severe pain and vision loss.
Spontaneous hyphema (blood in the front chamber of the eye) in African American patients could be a sign of underlying sickle cell disease. Even a small hyphema can increase intra-ocular pressure. This can lead to hyphemic glaucoma. This is a result of a blood cell obstruction within the trabecular meshwork.
Posterior segment findings include optic neuropathies, retinopathies, maculopathies, retinal hemorrhages, choroidopathy, vascular changes associated with tortuosity, “silver-wire” arterioles, angioid streaks, and arterial and vein occlusions.
Conservative management with close observation is warranted for non-proliferative sickle cell disease. Patients who present with stage 3 to 5 proliferative disease should be referred to a retina specialist. Also, continuous communication with the patient’s PCP is a must. The patient’s PCP should be aware of all findings from a routine eye exam and retinal evaluation.
For the ophthalmic or optometric technician, it is extremely important to take an accurate case history. It is also important to be familiar with the lab analysis used to diagnose sickle cell anemia to co-manage a patient’s care.