Pathology of the eye Flashcards
what is the inverse care law
the availability of good medical care ends to vary inversely with the need for it in the population served
what is leading cause of blindness worldwide
- cataract
uncorrected refractive error
age-related macular degeneration
diabetic retinopathy
glaucoma
corneal opacities
what are cataract risk factors
age
diabetes
trauma
inflammation
steroid use
UV/radiation
congenital
what are corneal ulcer risk factors
CONTACT LENSES
varicella/herpes
steroid drop use
dry eyes/ exposures
trauma/burns
what is the red reflex
what is an abnormal retinal reflex
retinal reflex
if anything is obstructing the path of light from the front to the back of the eye
what is retinoblastoma
how is it caused
cancer of the retina
RB1 gene (tumour suppressor gene)
- Hereditary- earlier and bilateral
- Non-hereditary- later and unilateral
therefore every newborn gets a retinal reflex check
why do patients get diabetic retinopathy
reduced vision due to
growth of new vessels
vitreous haemorrhage
tractional retinal detachment rubeotic glaucoma
NEW VESSELS ELSEWHERE (NVE)
-HAEMORRHAE from new vessels occurs in proliferative DR
in severe DR
-fibrosis with tractional retinal detachment
leakage of fluid from damaged vessels
macular oedema with loss of central visual acuity
how to treat diabetic retinopathy
not a cure
-slow progression
LIFESTYLE- smoking, weight, exercise
blood sugar, pressure, cholesterol
support renal function
LASER
ANTI-VEGF (injection) prevent new blood vessels forming in the back of the eye
SURGERY
describe the pathogenesis of diabetic retinopathy
HIGH GLUCOSE
-glycation
-oxidative/reductive stress
causes
MICROVASCULAR ENDOTHELIOPATHY/DAMAGE
-increased permeability
-capillary occlusion
-neovascularisation
what is retinopathy of prematurity
STEVIE WONDER
Normally, the blood vessels of the retina start to develop in the fourth month of pregnancy and finish developing around the due date, or 9 months of pregnancy.
If a baby is born very early, these blood vessels may stop developing normally. The retina then develops new blood vessels that are abnormal.
It is thought to be caused by disorganized growth of retinal blood vessels which may result in scarring and retinal detachment. Preterm babies are at risk for ROP, and very low birth-weight is an additional risk factor. Both oxygen toxicity and relative hypoxia can contribute to the development of ROP.
it is the 3rd epidemic in middle-income countries
what is age-related macular degeneration
what is its treatment
most common cause of SSI in over 65 in HIC
progressive reduction in central visual acuity
due to thinning of the macular
prevention with vitamin supplements
rehabilitation
anti-VEGF injection
what are the two types of age related macular degeneration
DRY- most common
- thinning of the macular
WET
- vessels leak fluid/ blood into the macular
- METAMORPHOSIA
(shape of object is distorted)
what is glaucoma
treatment
disease of the elderly
OPTIC NEUROPATHY
with visual field defect
raised IOP
treatment:
drops/ surgery
what is optic disc swelling
also known as PAPILLOEDEMA
two types
- PSEUDO SWELLING
-small discs
-DRUSEN
-anomalous elevation of one or both optic discs without edema of the retinal nerve fiber layer - GENUINE SWELLING
-swelling of optic disc due to ICP, space occupying lesion, idiopathic intracranial hypertension, hydrocephalus
what are symptoms of ICP
headaches
vomiting/nausea
visual disturbance
tinnitus
confusion
pupillary abnormalities
diplopia
