Age related macular degeneration (AMD) 0.0 / 5 ? MedicineOphthalmologyUniversityAll boards Created by: zCreated on: 13-03-16 18:03 AMD gradual loss of central vision may be v slow, over years or sudden deterioration if assoc w/ haemorrhage first symptom ususlaly distortion eventual severe loss of central vision but maintain peripheral vision difficulty w/ reading, recognising faces use Amsler chart square grid, one eye at a time, mark any distortions on chart 1 of 6 AMD gradual loss of central vision may be v slow, over years or sudden deterioration if assoc w/ haemorrhage first symptom ususlaly distortion eventual severe loss of central vision but maintain peripheral vision difficulty w/ reading, recognising faces use Amsler chart square grid, one eye at a time, mark any distortions on chart 2 of 6 Dry AMD geographic atrophic causing severe central vision loss accounts for 90% of AMD no Rx that can halt or reverse the progression precursor lesion that leads to geographical atrophy is a small yellowish macular lesion called 'drusen' of which there are 2 types- soft or hard soft drusen: pale yellow, large, ill-defined margins- sign of AMD if >63 microns and pt >55yrs, evolve to macular degeneration hard drusen: round, yellow, well definied margins- relatively common not always assoc. w/ AMD 3 of 6 Wet AMD less common but more severe 10% of AMD but 90% of blindness from AMD characterised by choroidal neovascularisation (CNV) CNV: the development of abnormal blood vessels beneath retinal pigment epithelium (RPE) layer of the retina identified on funduc flouroscein angiography new bvs penetrate into the macula region and bleed this causes macula scarring (disciform scar) which causes loss of central vision most eyes with AMD due to CNV udner the fovea are legally blnd w/in 2 yrs of diagnosis 4 of 6 Progression of AMD + risk factors Drusen evolve from hard to soft, incr in size, number and confluence - evolve to dry or wet macular degeneration 5 yr risk of pt >80yrs w/ soft drusen is 42% if AMD in one eye, risk of fellow eye developing AMD is 39-55% progression: no maculopathy + hard drusen > soft drusen +/- pigment changes > geographic atrophy/CNV + disciform scar risk factors: age smoking FHx complement factor H gene (CFH) possible RFS: sunlight CV: high BP, high chol, obesity 5 of 6 AMD treatment dry no Rx magnifiers for reading vitamins- if advance AMD in one eye to prevent deterioration in other eye- high dose zinc and antioxidant vitamins (vit C, vit E, beta-carotene) severely sight impaired/sight impaired registration social support wet previously- verteporfin ranibizumab, bevacizumab (avastin) non-selective VEGF-A inhibitors b/c VEGF-A implicated in bv growth and leakage, involved in CNV intravetreal injections, either in clean room or theatre- risk of endophthalamitis 2 year course can stabilise condition and sometimes restore vision aflibercept soluble VEGF receptor fusion proteins- binds all forms of VEGFA,B 6 of 6
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