Age-Related Macular Degeneration

 Age-Related Macular Degeneration

Definition

Progressive degeneration of the macula in elderly patients.

Epidemiology: 

Age-related macular degeneration is the most frequent causeof blindness beyond the age of 65 years.

Pathogenesis: 

Drusen develop in the retinal pigment epithelium due toaccumulation of metabolic products.

Symptoms: 

Patients notice agradualloss of visual acuity. Where macularedema is present, patients complain of image distortion (metamorphopsia), macropsia, or micropsia.

Findings and diagnostic considerations: 

Ophthalmoscopic examinationcan distinguish two separate stages that occur in chronological order (Table 12.6).


Differential diagnosis: 

Other vascular diseases of the retina such as branchretinal vein occlusion should be excluded by ophthalmoscopy. Malignant melanoma should be excluded by ultrasound studies.

Treatment: 

No reliably effective medical therapy is available. Laser therapymay be performed in the exudative stage in about 5 – 10% of all patients without neovascularization involving the fovea centralis. Use of progressively stronger near vision aids such as a hand magnifier or binocular magnifier should be tried.

Clinical course and prognosis: 

The course of the disorder is chronic andleads to progressive loss of visual acuity.

Laser therapy may be performed in the exudative stage of late age-related macular degeneration in 10% of all patients provided the dis-order is diagnosed early.

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