2020–2021 BCSC Basic and Clinical Science Course™
12 Retina and Vitreous
Part II: Disorders of the Retina and Vitreous
Chapter 07: Other Retinal Vascular Diseases
Sickle Cell Retinopathy
Management of Sickle Cell Retinopathy
All black patients presenting with a traumatic hyphema should be screened for a sickling hemoglobinopathy (including Hb AS trait) because of the increased risk of complications in the presence of rigid sickled erythrocytes. Control of intraocular pressure (IOP) may be difficult, and ischemic optic neuropathy may result from even short intervals of a modest increase in IOP. Early anterior chamber washout in the presence of a hyphema with increased IOP is recommended. In addition, carbonic anhydrase inhibitors should be used cautiously in sickle cell patients as they may worsen sickling through the production of systemic acidosis.
-
McLeod DS, Merges C, Fukushima A, Goldberg MF, Lutty GA. Histopathologic features of neovascularization in sickle cell retinopathy. Am J Ophthalmol. 1997;124(4):455–472.
Photocoagulation
Peripheral scatter photocoagulation applied to the ischemic peripheral retina generally causes regression of neovascular fronds and thus decreases the risk of vitreous hemorrhage. The decision to treat PSR with scatter photocoagulation should be made cautiously, however, because retinal tears and subsequent rhegmatogenous retinal detachment can occur and do so more commonly after such treatment in PSR than in proliferative diabetic retinopathy.
Vitreoretinal surgery
Surgery may be indicated for nonclearing vitreous hemorrhage and for rhegmatogenous, tractional, schisis, or combined retinal detachment. Retinal detachment usually begins in the ischemic peripheral retina. The tears typically occur at the base of sea fans and are often precipitated by photocoagulation treatment, as previously mentioned. Anterior segment ischemia or necrosis has been reported in association with 360° scleral buckling procedures, particularly when combined with extensive diathermy or cryopexy. During surgery, care should be taken to ensure adequate patient hydration and supplemental nasal oxygenation. Precautions for vitrectomy also include the judicious use of expansile gases to minimize IOP elevations postoperatively, which increase the risk of vascular occlusions. Exchange transfusion before vitreoretinal surgery is not recommended.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.