tailieunhanh - Ophthalmology A Short Textbook - part 7

Cour se lâm sàng và tiên lượng bệnh: viêm màng bồ đào Posterior do toxoplasmosis thường lành mà không có tổn thất nghiêm trọng của thị lực điểm vàng không tham gia. Tuy nhiên, nó có thể tái phát bất cứ lúc nào. Không có cách chữa đối với hình thức bẩm sinh. | 349 Recurrent toxoplasmosis. --------------------------------------- 350 Cytomegalovirus retinitis. Cytomegalovirus retinitis occurs in 20-40 of older patients. Peripheral retinal necrosis and intraretinal bleeding Fig. are frequently observed. Vascular occlusion is rare. Secondary rhegmatogenous retinal detachment may develop. These lesions heal to produce fine granular pigment epithelial scars. Less frequently AIDS may involve retinal infection caused by herpes simplex and varicella-zoster viruses Toxoplasma gondii or Pneumocystis carinii. The diagnosis of a viral retinal infection in AIDS is confirmed by attempting to obtain positive serum cultures and by resistance testing. Differential diagnosis Inflammatory retinal changes due to other causes should be excluded by serologic studies. Treatment Microangiopathy does not require treatment. Viral retinitis is treated with ganciclovir or foscarnet. Herpes simplex and varicella-zoster viruses are treated with acyclovir. Proph ylaxis Ophthalmologic screening examinations are indicated in the presence of known viral infection. Clinical course and prognosis The prognosis for microangiopathy is very good. Infectious retinitis will lead to blindness if left untreated. Visual acuity can often be preserved if a prompt diagnosis is made. Retinal Inflammatory Disease 351 Viral Retinitis Definition Retinal disorder caused by viral infection. Epidemiology Viral retinitis is a rare disorder Pathogenesis Infection of the retina and retinal vasculature caused by cytomegalovirus herpes simplex varicella-zoster or rubella viruses. Viral retinitis frequently occurs in immunocompromised patients. Sympt oms Patients report loss of visual acuity and visual field defects. Diagnostic consider ations Slit-lamp examination will reveal cells in the vitreous body. Ophthalmoscopic findings will include retinal necrosis with intraretinal bleeding see Fig. . Necrosis can occur as acute lesions and spread over the entire