Acquired Macular Diseases Flashcards
name 7 acquired macular diseases
-age related macular degeneration
-central serous retinopathy
-drug related retinopathies
-idiopathic macular hole
-epiretinal membrane
-cystoid macular oedema
-myopic maculopathy
what is AMD?
a progressive disease of the retina occurring in people over 55 years old causing damage to the macula resulting in loss of central vision while peripheral vision is usually spared
what kind of complaints do AMD patients report?
-reduced reading ability
-reduced ability to recognise people’s faces
-difficulty making out what people are saying
-initially starts out as distortion which turns into blur as central vision loss
what is the difference between prevalence and incidence?
Prevalence is number of cases overall and incidence is the number of cases per year
What are general stats on AMD?
-most common cause of blindness certification in people over 65 in the UK
-up to 30 million worldwide have AMD
-incidence of AMD in US is up to 200,00 people per year are diagnosed
what stats indicate AMD is increasing in prevelance?
-US and UK studies suggest that 20 –30 % of patients over the age of 65 are affected with AMD
-n UK 16 % of the population is currently over the
age of 65 and therefore at significant risk of
developing AMD
-The current demographic projections indicate that
the segment of the UK population over the age of
65 will increase by 29 % in the next 20 years
name the risk factors of AMD and state which is most common
– ageing
– smoking = most common
– family history AMD
– fair skin, light iris colour
– hypertension
– arteriosclerosis
– prolonged exposure to sunlight
pathogenesis of AMD
-drusen forms between bruchs membrane and the retinal pigment epithelium in dry AMD
-abnormal blood vessels grow under the rpe through retinal layers in wer AMD
-this is affected by genes, choroidal blood flow and inflammation
which form of amd is most common?
dry amd - 85-90% have dry amd and 10-15% have wet
what is the difference between dry and wet AMD?
dry is based on the absence of abnormal growth of blood vessels under the retina whereas wet is based on the presence of abnormal growth of blood vessels under the retina so in wet amd you would see blood leakages and drusen whereas in dry you would see just drusen
why does wet AMD cause more rapid and severe vision loss than dry AMD?
as in wet amd, the growth of abnormal blood vessels can cause leakage, bleeding and scarring
what are the signs if dry amd?
-non exudative
-drusen usually bilateral
-rpe hyperpigmentation
-geographic atrophy (later stage): round/ oval and well demarcated atrophy patches in the parafoveal/ foveal region
What are the three types of drusen?
-hard
-soft
-diffuse
-calcified
what does hard drusen look like?
Nodular, appear as
small discrete
yellowish-white spots
what does soft drusen look like?
– indistinct edges
– larger than hard drusen
– frequently become
confluent
describe diffuse drusen
– Represent a
widespread
abnormality of the
RPE
what’s different between the symptoms of dry and wet amd?
wet amd onsent of symptoms is sudden whereas in dry its gradual
what are the investigations for suspected amd in primary care?
-best corrected distance and near vas
-amsler grid
-fundoscopy
-oct
what is the neovascularisation in wet amd called?
-subretinal neovascular membrane (SRNVM) or choroidal neovascularisation (CNV)
what are the signs of wet AMD?
-pigment epithelial detachment
-retinal thickening and elevation
-subretinal fluid pinkinsh/ grey in colour
-blood
-exudate
-fibrosis
what amd investigation are done at secondary/ tertiary referral?
Further OCT, OCTa
why may you not advise a patient with AMD to get surgery?
May not be realistic as it is a complex surgery which may not have a positive outcome for majority of patients
what can high speed video
angiography be useful for when investigating amd?
it can help show feeder vessels in choroidal neovascularisation of wet amd
what referrals should you give for the two types of amd
wet - URGENT
dry - non urgent