Key points 15 Flashcards
What treatment is indicated in multifocal choroiditis due to Brucellosis?
tetracycline, doxycyline or rifampicin.
What is the formula to calculate SEM?
SEM = Standard deviation/square root of sample size
What 2 factors affect SEM?
As sample size increases, S.E.M. decreases
As standard deviation increases, S.E.M. increases
What is Schwartz’s syndrome
high IOP associated with a rhegmatogenous retinal detachment. Photoreceptor outer segments (+- RPE pigment) migrate transvitreally into the aqueous, block the trabecular outflow pathways, and result in IOP elevation.
What sign will help distinguish congenital from acquired Horner’s syndrome?
Sympathetic innervation plays a role in the development of pigmentation of the iris. Congenital interruption of the sympathetics to one eye will result in the ipsilateral iris having less pigment than the fellow eye.
Biopsy of an eyelid lesion shows intra-epidermal proliferation of atypical spindle-shaped melanocytes. What is the most likely diagnosis?
lentigo maligna
Which visual field defect on Humphrey perimetry corresponds to the greatest glaucomatous optic nerve damage?
A superior altitudinal defect in the context of glaucoma represents a substantial loss of optic nerve function, and one that encroaches near to fixation
What are the features of Brown syndrome?
congenital or acquired aetiology
inelastic superior oblique muscle tendon complex
restriction of passive or active elevation in adduction
downshoot of the eye on adduction (but no superior oblique overaction)
no superior oblique overaction
V-pattern is common
How to differentiate Brown syndrome from IO palsy?
positive forced duction test in Brown’s, negative in IO palsy
superior oblique overaction is uncommon in Brown’s but typical of IO palsy
The Geneva lens measure assesses:
the surface curvature of a lens
What are the Ocular features of fetal alcohol syndrome:
epicanthal folds
strabismus
blepharophimosis
long eyelashes
microphthalmia
telecanthus
Peter’s anomaly
anterior segment dysgenesis
tortuous retinal vessels
optic nerve hypoplasia
persistent hyaloid vessel
The most common location of a retinal tear is:
60% of retinal tears occur in the supero-temporal quadrant.
Which topical beta-blocker is LEAST likely to cause bradycardia:
Carteolol has intrinsic sympathomimetic activity, thus inducing less bradychardia and bronchospasm than timolol.
What is the most common cause of bleb failure after trabeculectomy?
bleb scarring due to episcleral fibrosis
The volume of aqueous humour in the anterior chamber is:
There are 250 microlitres of aqueous in the anterior chamber.
What is the most common bacterial aetiology in acute dacryocystitis?
Staphylococcal species
Which IOL material is most likely to develop late calcification?
Hydrophilic acrylic IOLs are the most susceptible to calcification, though this is a rare event with modern lenses.
Which is the site of pathology in Coats disease:
The vascular abnormality in Coats disease is the result of an abnormal endothelium in arterioles and venules. This causes massive leakage of lipid-rich plasma into the retina and the subretinal space.
Which optic disc anomaly may be found in conjunction with aniridia?
Optic disc hypoplasia can be associated with:
septo-optic dysplasia
aniridia
fetal alcohol syndrome
maternal: LSD, quinine, and phenytoin
What anaesthetic agent elevates intraocular pressure?
Ketamine and succinylcholine
Parents bring their 10-month-old child to you because of chronic right-sided epiphora. They have been massaging the right nasolacrimal sac for the past 6 months; however, the epiphora has persisted.
Silicone stent intubation is indicated in this patient when:
nasolacrimal system probing has proven unsuccessful
The best predictor of future contralateral visual loss in a patient with a disciform macular scar from presumed ocular histoplasmosis syndrome (POHS) is the presence or absence of:
The likelihood of contralateral choroidal neovascularization (CNV) in a patient with a disciform macular scar from presumed ocular histoplasmosis syndrome (POHS) is increased if there are focal macular scars in the better eye.
