Sickle Cell retinopathy.pptx Sickle cell disease and its effect on the eye

how sickle cell can affect the eye

1. Sickle Cell retinopathy

2. Sickle Cell Anemia SC is number one of the hemoglobinopathies It disproportionately affects people of African descent SC anemia is a disabling chronic hemolytic anemia It is characterized by production of abnormal hemoglobins that deform and stiffen red blood cells This causes increased blood viscosity and microcirculation occlusion to varying degrees throughout the body.

3. Sickle Cell Retinopathy Sickle cell is inherited as an autosomal recessive pattern. Different types of sickle cell disease arise based on whether the hemoglobin beta S gene is inherited with another beta S gene or with a different beta gene mutation Hemoglobin SS disease: Hemoglobin SB 0 (Beta zero) Thalassemia Hemoglobin SC disease Hemoglobin SB+ (Beta) Thalassemia Hemoglobin SD, Hemoglobin SE, and Hemoglobin SO

4. Hemoglobin SS disease Most common variant of the disease Most severe type of sickle cell disease Occurs when hemoglobin S gene mutation is inherited from both parents. In this type, the body only produces hemoglobin S. This is often called “Sickle cell anemia”

5. Hemoglobin SB 0 Thalassemia Occurs when hemoglobin S gene mutation is inherited from one parent and a hemoglobin beta0 thalassemia gene mutation from the other. Has similar symptoms to hemoglobin SS disease Also called sickle cell anemia because the body only produces hemoglobin S

6. Hemoglobin SC disease Second most common type of sickle cell disease Occurs when a hemoglobin S gene mutation is inherited from one parent and the hemoglobin C mutation from the other parent. Individuals with SC disease may have symptoms similar to individuals with SS The symptoms may be less severe though.

7. Hemoglobin SB+ Thalassemia Occurs when the hemoglobin beta S gene mutation from one parent and a hemoglobin beta plus thalassemia gene mutation from the other parent. Some normal beta hemoglobin is produced, but in reduced quantities. This form of sickle cell disease is less severe than hemoglobin SS disease. Symptoms are usually milder than SS or SC disease, but complications can still develop.

8. Symptoms Usually without ocular symptoms When they do occur: F loaters Flashing lights Loss of vision with advanced age Systemically: Painful crises – severe abdominal or musculoskeletal discomfort.

9. Signs Critical Peripheral retinal neovascularization – sea fan hemorrhage Sclerosed peripheral retinal vessels Dull grey peripheral fundus colour – result of peripheral arteriolar occlusions and ischemia. Other Venous tortuosity Mid periphery fundus pigmented lesions with spiculated borders (sunbursts) Superficial intraretinal hemorrages (salmon patch) Refractile intraretinal deposits following hemorrhage resorption Angioid streaks

10. Signs cont’d Other Comma-shaped capillaries of the conjunctiva Vitreous hemorrhage and traction bands RD CRAO Macular arteriolar occlusions also occasionally occur

11. Sea fan hemorrhage

12. Proliferative SCR

13. Salmon patch

14. SCR OCT

15. Staging 5 stages of SCR severity STAGE 1: Peripheral arteriolar occlusions STAGE 2: Peripheral arteriovenous anastomoses STAGE 3: Neovascular proliferation STAGE 4: Vitreous hemorrhage STAGE 5: Retinal detachment

16. Differential Diagnosis of peripheral retinal neovascularization Sarcoidosis : Peripheral sea-fan neovascularization often associated with uveitis. DR More posterior. Associated dot-blot hemorrhages Embolic retinopathy Hx of IV drug abuse. May see refractile talc particles in macular arterioles Eales disease Peripheral retinal vascular occlusion of unknown etiology; diagnosis of exclusion Others: ROP, familial exudative vitreoretinopathy , chronic myelogenous leukemia, radiation retinopathy, pars planitis , carotid-cavernous fistula, ocular ischemic syndrome, collagen-vascular disease.

17. Work Up Medical Hx and family Hx : Sickle cell disease, diabetes, or known medical problems? IV drug abuse? Dilated fundus exam – direct ophthalmoscopy Sickledex , sickle cell preparation and hemoglobin electrophoresis. Patients with sickle cell trait, as well as hemoglobin C disease may have – ve Sickledex results. Consider IVFA to aid in diagnosis – rarely necessary

18. Treatment No well- established indications or guidelines for treatment Isolated retinal neovascularization is not an indication. Neovascularization with associated vitreous hemorrhage – pan retinal photocoagulation (PRP) RD treated with vitrectomy . If SCR is diagnosed or suspected, Refer to an ophthalmologist

19. Follow-up No retinopathy – Annual dilated fundus examination Retinopathy – repeat dilated fundus examination every 3-6 months, depending on severity.