diabetic retinopathy
diabetic papilopathy
-self limited, sometimes bilateral -optic disc swelling caused by vascular leakage and axonal edema - may have hard exudates and intaretinal hemorrhages - may affect other nerves as well through microstrokes
with decreased oxygen, how does the eye respond? does this have any negative effects?
-the eye will release VEG F to increase neovascularization of the ischemic areas -this also occurs throughout the rest of the eye however, -in the iris and the anterior chamber angle - this will block drainage of the eye and can lead to increased pressure in the eye leading to neovascular glaucoma - also grow along optic nerve and retina and these vessels are very incompentent with lots of leaking into the retina or into the vitreous (VITREOUS HEMORRHAGE)
what happens when retinal blood vessels become leaky
-the otherwise dry retina becomes wet and filled with proteins that show up as yellow hard exudates -fluid also leaks into th macula leading to macular edema -blood also leaks leading to dotblot hemorrhages all of these get in the way of light from getting to the retina leading to distortion and double vision
retinal finding consistent with proliferative diabetic retinopathy
vitreous hemorrhage
deoxygenation structures of the eye in diabetes
blood vessels are leaky from diabetes but also more than likely narrowed from HTN leading to poor oxygenation of the structures of the eye that need it
chronic changes to lens as a result of diabetes
cataractish changes that may take the form of a snowflake
diabetic eye problem tx
control sugars!! then treat the structure that is affected
rupturing of blood vessels in superficial/ant retina
flame hemorrhages
cotton wool spots
infarcted nerve fibers on the ant or superficial retina causing white spots i
mucormycosis infection in orbit -when most susceptible -present with -may find -to confirm -prognosis -tx
ketosis or hyperosmosis nonketotic acidosis they are most succeptible to this fungus -presents in obtunded state with redness and swelling of eyelids -may find esher on nose or roof of pallate -need tissue biopsy to confirm -poor prognosis especially if access to the brain through the cavernous sinus -antifunguls like amphotericin as well as surgical removal that probably is exenteration
how are retinal blood vessels affected in diabetes
pericytes (that normally prevent leakage into the surrounding retinal tissues) are very sensitive to elevated levels of glucose that gets converted to sorbitol and deposits this causes them to die leading to leaky retinal blood vessels (may cause microaneurysms as well)
pupil sparing CN III or VI palsy
results from diabetic papilopathy microstrokes
what structure of the eye is most sensitive to elevated blood glucose
retinal blood vessels
proliferative diabetic retinopathy
the changes the result from VEG F increase non proliferative is the changes before VEG F is released
how is lens affected acutely by increased glucose
the increased glucose changes to sorbitol which leads to swelling of the lens which blurs vision that resolves when glucose levels get back to normal
diabetes mellitus
type 1 - pancreas doesn't produce enough insulin type 2- body doesn't respond to insulin
one of the leading causes of blindness in the USA
vision loss from diabetes (permanent)