OPTHALMOLOGY 8 Flashcards
tapetum is only in which half of the fundus? (dorsal vs ventral)
dorsal
4 reflexes to eb tested during neuropthalmuc exam
menace
dazzle (very bright light source causes a blink)
pupillary light
palpebral
what are the 3 types of opthalmoscopic examinations?
which one provides an upside-down view?
distant direct opthalmoscopy
close direct opthalmoscopy
indirect opthalmoscopy (UD)
what is the function of tropicamide in opthalmic examinations?
how long to take effect?
parasympatheticolytic: causes mydriasis
15-20 mins to take effect
what are the side effects of atropine
decreases tear prod
increased intraocular pressure
salivation
hyper vs hypo?
hyper vs hypo?
what are these
progressive retinal atrophy (PRA) affects what structure in the eye?
between rods and cones, which is affected first?
which is lost first: night or day vision?
tx?
retinal photoreceptors
rods
night vision
no tx, but condition is painless
what are the changes to retinal appearance in PRA?
bilaterally symmetric: diffuse tapetal hyperreflectivity
vascular attenuation
optic nerve atrophy
progressive retinal atrophy y(PRA) takes how long before full vision loss?
usually 18 months. progressive loss, so good quality of life
what condition?
retinal dysplasia is due to what structural change in the retina?
retinal folds & rosettes
what r the 3 types of retinal dysplasia?
which is the most severe?
multifocal
geographic
total (S)
what is SARDS (Sudden Acquired Retinal Degeneration Syndrome)
typically occurs in which type of dogs?
sudden onset blindness with normal fundus appearence
middle age small breed female
what are the 3 clinical signs of SARDS
*vision loss w normal fundus
*PUPD
*PLR absent with RED light only
how can SARDS diagnosis be confirmed? (other than PLR)
electroretinogram: abscent trace
what are the 4 causes/types of chorioretinities?
-infectious
-inflammatory
-neoplasia
-immuen mediated
what are some features of active chorioretinitis
inflammatory cells around retinal blood vessels
retinal oedema, focal haemorrhage, retinal detachment
what are some features of chronic chorioretinitis
focal, sharply demarcated densely pigemnted lesions
what are 5 causes of retinal hemorrhage
hypertension
coaulopathy
trauma
chorioretinitis
septicaemia
what are the two types of retinal detachemnts?
total
bullous
what is a Rhegmatogenous detachment
tear in retina -> disinsertion from periphery.
what are the 4 optic nerve diseases
optic nerve hypoplasia
optic nerve atrophy
optic neuritis
optic nerve cupping
what is optic nerve hypoplasia
rare congenital hypoplasia -> disc is abnormally small
what is optic nerve atrophy
What does it look like on the fundus view?
advanced retinal degeneration
what is optic neuritis?
What does it look like on the fundus view?
inflammation of the optic nerve. appears swollen and hyperaemic
what is optic nerve cupping
Compression of the optic
nerve head due to high
intraocular pressure
