neuro ophthalmology Flashcards
(22 cards)
what are the pupillary reflexes?
light reflex and near reflex
what are the pupillary reflexes?
direct and and consensual light reflex
Breifly describe the pupillary [athway?
retina to pretectal nucleus
pretectal nucleus to Edinger-Wesphal nucleus
edingar - westphal nucleus to third cranial nerve and ciliary nerve
what does near reflex consists of?
accomodation reflex and convergence reflex
what are the ways to check pupillary reflex ?
direct light
indirect light
swinging flashlight test
what are the abnormal pupillary reflexes and the reason behind every one of them?
- amauratic cat eye reflex - optic nerve damage
- efferent pathway defect
- marcus gunn pupil - RAPD (relative afferent pathway defect)
- wernickes hemianopic pupil - optic trat defect
- adies pupil post ganglionic parasym pupilarymotor damage
- argyll robertson pupil - neurosuphilis (accomodation reflex present )
what is optic neuritis?
inflammation and demylienation of the optic nerve
what are the causes of optic neuritis?
idiopathic hereditary - leders disease autoimmune - sarcoidosis , SLE infectious - tb , syphilis parainfectious - measles , chickenpox toxic neuritis demylienation disorders - multiple sclerosis
what are the types of optic neuritis according to anatomical classification?
papilitis
neuroretinitis
retro orbital neuritis
what is papillitis?
type of optic neuritis which involves the optic disc
what is neuroretinitis?
involvement of optic disc and macula of the retina in optic neuritis
what is retrobulbar neuritis?
neuritis of the optic nerve present behind the eye ball.
what does typical and atypical optic neuritis mean?
typical neuritis is demylination disorder that leads to optic neuritis (esp MS)
atypical is optic neuritis is due to other reasons other than demylienation.
clinical features of optic neuritis?
# SUDDEN monoocular progressive loss of vision # DIMINISHED dark adaptations # visual obscuration (sudden grey transient loss of vision) in bright light #IMPAIRED colour vision #movement and sound PHOSPHENES # transient obscuration of vision ON EXERTION # PULFRICH'S PHENOMINON (DEPTH PERCEPTION FOR MOVING OBJECTS LOST) # pain - mild (mostly in retrobulbar)
reason for pain during movement and which movement causes more pain?
un and down movement causes more pain in RETROBULBAR optic neuritis because of superior rectus attachment to the dura mater.
what is the most affected thing in optic neuritis?
colour vision is IMPAIRED.
SIGNS of optic neuritis?
- visual acuity - red.
- colour vision - impaired
- contrast sensitivity - impaired (desaturation)
- MARCUS GUNN PUPIL
- ophthalmoscope -
# disc - hyperaemia , blurred margin, splinter hemorrhage,
fine exudates, dics edema (2-3D)
#cup - obliterated
#retinal veins - engorged and tortuous.
# vitreous - inflammatory cells.
#macula - MACULAR STAR (inn neuroretinitis - involves
retina + optic disc) - visual feild changes - central and centrocaecal scotoma
- visually evoked response - low amplitude and red.
transmission time. - fundus fluorescein angiography - slight leak and inc. over time
what kind of changes in examination is found in retrobulbar neuritis?
no changes that are noticiable except maybe sometimes temporal pallor of disc.
DD for paillitis?
papilloedema
pseudopapilledema
ischemic optic neuropathy
ant. orbital compression neuropathy
DD FOR ACUTE RETROBULBAR OPTIC NEURITIS?
Hysterical blidness
cortical blindness
indirect optic neuropathy
malingering
what is the investigation found to diagnose optic neuritis early?
multifocal visually evoked response
what are the investigations done for optic neuritis?
multifocal visually evoked response
mri of brain
optic nerve mri - gadolinium enhanced
brain - cerebral cerebellar, brainstem
