Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells

Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells

International Journal of Research Studies in Medical and Health Sciences Volume 3, Issue 11, 2018, PP 20-23 ISSN : 2456-6373 Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells Luis E. Abad1, Cruz Ruiz Gali Mauro2, Buy Rodrigo Andres2, BuyRubén Exequiel2 1 Directorat Of talmoAbad, Clínicade Ojos, Río Gallegos, Santa Cruz, Patagonia Argentina. 2Resident of Ophthalmology, Of talmoAbad, Clínica de Ojos, Río Gallegos, Santa Cruz, Patagonia Argentina. *Corresponding Author: Dist. Prof. Dr. Luis Emilio Abad, Directorat Of talmoAbad, Clínicade Ojos, Río Gallegos, Santa Cruz, Patagonia Argentina INTRODUCTION Stage 2: Peripheral arteriovenous anastomoses begin to appear as existing We can consider sickle hemoglobinopathiesare dilated capillary channels. After vascular due the presence of one or several abnormal occlusion, the peripheral retina appears for hemoglobins with abnormal red blood cell the most part avascular and with no capillary formation under conditions of hypoxia and perfusion. acidosis. Stage 3: Presents the beginning of The deformed red cells are rigid, being able to neovascularization from the anastomoses. In obstruct the small blood vessels and cause the beginning, the new vessels remain flat in hypoxia. the retina and show a fan-shaped In a normal erythrocyte, hemoglobin. Which is configuration (neovascularization in "sea composed of four alpha chains and two beta fan", this name resembles a marine chains. At the position of glutamic acid in the invertebrate). beta chain is precisely where we can find a point of mutation. If it was replaced by the lysine, we Stage 4: It is characterized by the presence of will have the formation of a hemoglobin. If we vitreous hemorrhage of variable degree. had valine, we will have a hemoglobin. Hemorrhage can be caused by ocular trauma, which is sometimes unimportant. I can also find an AS (carrier of the sickle stroke), an AC association (carrier of Stage 5: There is a traction of the vitreous hemoglobin C), the SS form (sickle-cell and retinal detachment. anemia), the SC form (sickle cell disease of the Rhegmatogenous retinal detachment may also Hb C carrier). appear as a result of a tear formation adjacent to There are also other abnormalities in the the areas of fibrovascular tissue. synthesis of the blood chain alpha or beta, this will cause the so-called thalassemia, when We can find other non-retinal manifestations: combined with a sickle hemoglobin, then the Conjunctiva: it is common to see sickle or Sthal thalassemia. conjunctival isolated dark red vascular OCULAR MANIFESTATIONS segments with a "coma" or "corkscrew" The most serious forms of retinopathy are those shape, affecting the vessels of small caliber, that appear in the diseases SC (sickle cell being the most common location in the lower disease with hemoglobin C) and Sthal part of the conjunctiva. (Thalassemia). Uvea: in the iris we can find a circumscribed Sometimes milder hemoglobinopathies can also area of ischemic atrophy, usually going from cause retinopathy. the pupillary edge to the sphincter and Proliferative Falciform Retinopathy can be sometimes with rubeosis. divided into five stages: In nonproliferative retinopathy there may be Stage 1: It is characterized by peripheral asymptomatic lesions such as tortuous veins, arteriolar occlusions. "sun figure" pigmentations (black sunbursts, peripheral chorioretinal atrophy), "salmon International Journal of Research Studies in Medical and Health Sciences V3 ● I11 ● 2018 20 Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells plaque" hemorrhages (pink superficial accumulation of pigment that was already superficial hemorrhages), bright spots (deposits mentioned, the so-called "black sunburst of peripheral hemosiderin, located inside the sign". Stage two with the presentation of the cystic cavities), peripheral arterioles in "silver anastomoses, in an attempt to revascularize the thread", retinal breaks specially in the equator damaged regions, angiography will show andangioidstreaks in rare cases. hyperfluorescent vessels at the edge of the ischemic areas, unlike neovessels, they do not Symptomatic lesions may be various occlusions extravasate contrast. These anastomoses are of the central artery of the retina, macular obstructed in hypoxia crises and they will arteriole, central vein of the retina and vascular develop neovessels, which do provoke occlusions of the choroid. extravasation of contrast. In the optic disk, it is common to see small We can observe in stage three the transient red spots, caused by accumulation of neovascularization that was previously sickle cells. described and that we compare with the shape of a "fan" or a marine invertebrate, called Gorgonia Flabellum "be fan". In the angiography we will see these neovessels constituted by a nourishing arteriole, a capillary network and a drainage venule. The process will become increasingly extensive. The damaged retina is usually the superior temporal, followed by the superior nasal, inferior temporal and inferior nasal. In the fourth stage, there will begin to be an Figure1. Retinography of a patient with sickle cell adhesion of the neovascular vitreous complex retinopathy, stage 4 with hemovitreous. with the provocation of hemorrhage by vascular traction, this being the first sign of disease with the subsequent formation of fibroglial tissue, with greater adherence of the neoformed vascular tissue. In 60% of cases spontaneous occlusion of the neovessels occurs, unfortunately this is accompanied by neovascularization complicating the process. The slow blood flow predisposes the formation of clots. And finally stage 5, is the traction of the vitreous adhered with the formation of tears Figure2. Image showing fibroglial tissue with and retinal detachment as already described vitreoretinal traction in Thalassemia above. FLOURESCEIN ANGIOGRAPHY Generally in the posterior pole, the great vessels of the retina are normal, and may be tortuous, caused by peripheral arteriovenous anastomoses, sometimes encountering multiple obstructions of the perifoveal retinal capillary network. In the first stage, we will observe dark areas of hypofluorescence due to the absence of vessels, especially in the extreme periphery of the retina and around these areas will be the amputated vessels in their path in whose obstructed limb Figure3. Fluorescein angiography of a patient with we will see an accumulation of contrast. There thalassemia, presenting stage 3 sickle cell will also be peripheral retinal hemorrhages that retinopathy, where we can observe a peripheral dissect the subretinal space, causing an neovascularization with the "Sea Fan" image. 21 International Journal of Research Studies in Medical and Health Sciences V3 ● I11 ● 2018 Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells Photocoagulate all ischemic areas. The power of the laser should be slight to avoid occlusion of the choroidal vessels and rupture of Bruch's membrane, when the retina is hyperpigmented. Figura4.Retinographyshowinganhemorragestagepro vokedbyretinopatysicklecells Figure7. Sickle cell Retinopathy scheme treated with peripheral circular photocoagulation. Spot: 200-500um,Time: 0.2 s, Periphery: 360º Figure5. Fluorescein angiography of the previous image. Figure8. Fluorescein angiography, showing the peripheral scars by photocoagulation, following the Figure6. Another case of thalassemia, showingin this treatment scheme angiography a neovascular tuft,fed by a nutritious arteriole (feeder),giving an image "Sea Fan". It would be very important to close the neovascular membrane through the occlusion of TREATMENT the arterial feeder (afferent vessel), this can be Argon laser photocoagulation with peripheral associated with the destruction of the ischemic circular pattern in the retina, to treat the areas of retina and never as an isolated procedure, since absence of capillary perfusion, causes the we would not be treating the cause and the regression of the lesions in a high percentage of consequence. Another option is peripheral cases. cryotherapy, this being more aggressive we should leave this technique for cases in which The treatment must be divided, no more than 2 the vitreous hemorrhage prevents us from hours in each session. We must be careful visualizing the fundus. during the treatment of non-photocoagulation directly the neovessels to avoid hemorrhage, and The pars planavitrectomy in the detachment of monitor the pulse of the central artery of the the retina by traction and / or in persistent retina and branches because of the high risk of vitreous hemorrhage, sometimes the post- occlusion that exists during photocoagulation. surgical result is not what we expect. International Journal of Research Studies in Medical and Health Sciences V3 ● I11 ● 2018 22 Diagnosis and Treatment of Hemoglobinopathy and Retinopathy of Sickle Cells Sometimes the association of vitrectomy with We will evaluate the patient with a fluorescein the placement of a scleral buckle is necessary angiography in short times, to investigate if when there is an associated rhegmatogenous there is activity or not of the neovascular tuft retinal detachment. In these cases always and appearance of new ischemic areas. perform an ultrasound evaluation. REFERENCES These patients are prone to have sickling crisis caused by the surgical act, general anesthesia, [1] Welch AB, Goldberg MF. Sickle-cell which can cause ischemia of the optic nerve and hemoglobin and its relation to fundus the macula

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