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What is 'Sea-Fan' retina is seen in- and explain in detail?
SICKLE-CELL RETINOPATHY Retinal changes in patients suffering from sickle cell haemoglobinopathies (abnormal haemoglobins) areprimarily caused by retinal hypoxia; which results from blockage of small blood vessels by the abnormal- shaped rigid red blood cells. Clinical features Sickle-cell retinopathy can be divided into five self-explanatory stages as follows: 1. Stage of peripheral aeriolar occlusion. 2. Stage of peripheral aeriovenous anastomoses. 3. Stage of neovascularisation. 4. Stage of vitreous haemorrhage. 5. Stage of vitreoretinal traction bands and tractional retinal detachment. Treatment  Panretinal photocoagulation (PRP) is effective in regressing the neovascularisation.  Pars plana vitrectomy is required for vitreoretinal tractional bands. It should be followed by repair of the retinal detachment, when present Ref:comprehensive ophthalamology A k khurana 4/E pageno:264.