Eye Flashcards
What is the use of telescope lens?
for chromatic aberration correction
What is biometry?
calculation of IOL power
- Why is retinoscopy is done?
- when does it have no informative value?
- retinoscopy streak neutralisation means?
- for checking refractive power of the eye
- in patient of sudden visual loss
- that refraction is done in that meridan
Purpose of keratometer?
calculate power of front of cornea
What is measured by synaptophore?
Binocularity, retinal correspondence, angle of deviation, degree and range of fusion
In old age why does near vision decreases?
due to decrease curvature of lens
Anterior staphyloma is not?
myopic retinal change
cyclosporin MOA?
inhibit T-cell differentiation
Atropine action on eye?
paralysis of sphincter pupillae
MOA of local anaesthetics
bind to Na channels in ionised form or close Na channels
What is the primary determinant of local anaesthetic activity?
protein binding affinity and lipid solubility
Latanoprost MOA?
increase uveoscleral outflow and decrease aqueous production by 30%
MOA of atropine
competitive antagonist of muscarinic acetyl choline/ anti cholinergic
epinephrine avoided in patient taking?
amitriptyline
Drug that inhibit DNA gyrase and cell proliferation?
quinolone
What increases sensitivity to tetracaine and depolarising paralytic agents?
tetracaine
Drug causing lid retraction?
apraclonidine
Drug causing follicular conjunctivitis?
Brimonidine
Drug used to treat diabetic macular edema
Ranibizumab
Drug that cause parasympathetic blockade will cause?
dry mouth and mydriasis
When does sudden painless visual loss with no fundal glow occurs?
vitreous hemorrhage
When does sudden painless visual loss in young patient with no systemic problem occurs?
Eales disease
When does sudden painless visual loss in 25weeks pregnant lady occurs?
exudative retinal detachment
What is the first effect of HTN intraocularly?
Arteriosclerosis
Nuclear cataract conditions?
Rubella and smoking
Cortical cataract condition?
UV light and diabetes
Loss of contrast sensitivity is also a symptom of?
cataract
Posterior subcapsular cataract conditions?
Steroids and diabetes
Young boy having severe asthma treated by inhaled steroid might be at risk of developing?
Cushing syndrome
iridodonesis occurs due to?
Lens sublaxation
Xeroderma pigmentosa is caused because of? symptom?
caused = damage to DNA repair gene
symptom = corneal opacity
What is Potter syndrome?
ocular anomalies + corneal defect + lens prolapse
When do vossius rings form?
anterior lens after trauma
What is LEAST likely to influence the result of therapy?
Polarity of laser
Posterior staphyloma seen in?
dengerative myopia
Earliest visual field defect in POAG is?
isolated paracentral nasal scotoma
Damage to optic nerve head is in?
Chronic simple glaucoma
Superior and inferior polar cup notching is the specific sign of?
Glaucomatous change
Anterior chamber volume is greatest in?
congenital glaucoma
Buphthalmos is a sign of?
congential glaucoma
Hypermetropia is not a risk factor for?
POAG
Vogt’s triad seen in post attack of?
angle closure glaucoma
phacolytic glaucoma patient presents with?
raised IOP, deep anterior chamber, cells and flare, hypermature cataract and diabetes
Pigment dispersion in anterior chamber can lead to?
open angle glaucoma
Neovascular glaucoma is not a cause of?
sudden painless vision loss
In congenital glaucoma horizontal lines (Habb striae) are present on cornea due to?
disruption of decement membrane
Ophthalmia neonatorum - caused by? baby presents with?
Maternal vaginal gonococcus
pus discharge
Inclusion conjunctivitis is caused by?
Maternal vaginal chlamydia
What is the most common cause of viral corneal ulcer?
HSV-1
Retinitis pigmentosa which drug causes it?
Thioridazine
In iridocyclitis ‘water logging’ causes
increased water in iris stroma and release of prostaglandins cause miosis
Nanaophthalmia does not present as?
cystic palperbral bulge
In albinism there is? 3 things
photophobia, strabismus and nystagmus
Eye findings in turner syndrome are?
ptosis, blue sclera and dyschromatopsia
findings in Patau syndrome (trisomy 13)?
intraocular cartilage, ciliary body colobomas, small eyes, iris and ciliary body deformities, renal dysplasia and vasculature in vitreous
Persistant hyperplastic vitreous is
sporadic
CRAO likely cause is?
arteriosclerosis
What slows down the progress of diabetic retinopathy?
ipsilateral glaucoma and chorioretinal scarring
If a person has difficulty in looking down lesion is in?
midbrain
Band keratopathy means?
calcium deposits between cornea and bowman membrane
A pt can’t see laterally with his left eye and don’t feel sensations in the lower right body the lesion will be in?
internal capsule
Lesion of PICA=?
nystagmus, hemianopia, horner and loss of temperature sensation on face
Painful peripheral corneal ulceration of unknown ethology is called? treatment by?
mooren ulcer treated by steroids
White pupillary reflex (leukocoria) in an infant diagnosed with PHPV is because of?
hyperplastic pupillary membrane
When are rods and cones visible?
end of first trimester
When does corneal nerves appear?
5th month of gestation
when does the pupillary membrane disappears?
8th month of gestation
When does the frontal sinus form?
after birth
How long does the optic nerve take to me completely myelinated?
until 3 months after birth
Where are the sphincter and dilator pupillary muscles derived from?
ectoderm of optic cup
What is the afferent and efferent of corneal reflex?
ophthalmic branch of the trigeminal is afferent and facial nerve is efferent
What type of epithelium of cornea?
st. squamous non-keratinised
What is the corneal basement membrane attached to?
bowman layer
What anatomical limbus and what is surgical limbus?
Anatomical limbus is schwalbe’s line and surgical limbus is beginning of bluish area marking the transition between cornea and sclera
Canal of Schlemm/sinus venosus sclera location?
posterior to limbus and anterior to scleral spur
Where does the lacrimal nerve arises from? what are its components?
arises from origin of lateral rectus and includes sensory, sympathetic and parasympathetic components
what is the longest portion of optic nerve and its length?
intraorbital portion and length 25mm
where is the nucleus of oculomotor nerve?
midbrain
What is the blood supply of intracranial, intraorbital and intracanicular portion of optic nerve?
ophthalmic artery
What does lesion of Edinger Westphal nucleus cause?
absent light reflex and absent accomodation
Sympathetic supply to dilator pupillae?
long ciliary nerve
In cranium, what is the relation of optic nerve to internal carotid artery and anterior cerebral artery?
medial to internal carotid artery and inferior to anterior cerebral artery
Where do the infraorbital nerve and nerve from pterygopalantine ganglion run through?
inferior orbital fissure
In cavernous sinus, where do the trochlear nerve lie in respect to oculomotor and ophthalmic nerve?
Lies between oculomotor nerve above and ophthalmic nerve below.
HTN with blurred vision, improves on tilting to left side and right eye moves upward and inward, lesion?
right superior oblique
Bilateral peripheral vision loss after trauma to which vessel?
PCA
Where does PCA pass from in respect to oculomotor nerve?
PCA passes above oculomotor nerve and joins PCA to ICA
Afferent and efferent of light reflex?
afferent is optic nerve and efferent is oculomotor nerve
Trigeminal ganglion is like?
posterior root ganglion of spinal cord
Where is maxillary nerve?
pterygoid fossa
Central retinal artery lies? where does it emerge from?
lies within optic nerve and emerges from optic disc within optic nerve
Patient can easily see far objects and can move eye in all directions but cannot focus at near objects, this is due to?
dysfunction of short ciliary nerve and ciliary ganglion
Posterior part of posterior limb of internal capsule/ retrolental part of internal capsule related to?
optic radiation
