Key points 21 Flashcards
To maximize the elevation generated by the superior rectus, how must the eye be rotated from primary position?
abducted 23 degrees
Steps to prevent supra-choroidal haemorrhage include:
small incision
shelved or self-sealing incisions
decompress globe before surgery with digitial compression or device
close wound with non-absorbable sutures
keep blood pressure well controlled during surgery
deep anaesthesia if GA used
The definition of a giant conjunctival papilla is one which is over what diameter?
Giant papillae are over 1 mm in diameter.
What are the features of persistent primary hyperplastic vitreous?
PHPV is usually unilateral. It is often associated with microphthalmos. Presentation is variable, some cases can be observed while others may require lensectomy or vitrectomy.
Which ERG finding is most in keeping with choroideraemia:
the scotopic ERG is typically non-recordable while the photopic ERG is severely sub-normal.
What structures pass through the annulus of zinn?
abducent nerve
inferior branch of the oculomotor nerve
superior branch of the oculomotor nerve
nasociliary nerve
Where is the canal of Petit?
between the orbiculo-posterocapsular bundle and the anterior vitreous cortex.
Where is the canal of Hannover?
between the orbiculo-anterocapsular bundle and the orbiculo-posterocapsular bundle.
In a patient with AIDS and cytomegalovirus retinitis intravenous or intravitreal antiviral induction therapy is given for how long?
Either IV or intravitreal antiviral therapy may be used for the treatment of cytomegalovirus retinitis. Induction is typically carried out for 14 days. Once the retinitis is under control, maintenance therapy is given indefinitely.
Which is true of the post-operative course of donor endothelial cell counts following penetrating keratoplasty:
Endothelial cell counts decline rapidly in the first post-operative year, followed by a slow, unrelenting loss of endothelial cells over time.
Which congenital cataract is LEAST likely to impair vision significantly?
Anterior capsular cataracts are opacities of the anterior lens capsule and epithelium that do not usually affect vision.
A conjunctival inflammatory response characterised by multiple polygonal nodules with central fibrovascular cores is consistent with a:
papillary response
Conditions that produce CMO without leakage include:
Golmann-Favre
juvenile x-linked retinoschisis
retinitis pigmentosa
nicotinic acid maculopathy
Which visual disturbance is MOST typical of a patient presenting with acute posterior multifocal placoid pigment epitheliopathy (APMPPE):
APMPPE typically presents with subacute visual impairment, associated with central and paracentral scotomas and often photopsia. The symptoms usually commence in one eye, but within several days to weeks the fellow eye becomes affected.
What are the melanoma excision margins?
5mm to 1cm.
Which is the procedure of choice in a child with asymmetric but bilateral, moderate-to-severe congenital ptosis:
bilateral frontalis suspension
The most common malignant neoplasm of the lacrimal gland is:
Benign mixed (also known as pleomorphic) adenoma is the most common (benign) neoplasm of the lacrimal gland. Adenoid cystic carcinoma is the most common malignant neoplasm of the lacrimal gland.
What is the mechanism of action of hydroxyamphetamine?
Hydroxyamphetamine causes the release of noradrenaline from the presynaptic terminal. In first and second order Horner’s, noradrenaline released from the third order neuron causes dilation of the pupil. In third order Horner’s, this neuron is damaged and no noradrenaline is released (no dilatation).
In which conditions is argon laser trabeculoplasty MOST likely to be effective:
Primary open angle glaucoma
pigmentary glaucoma
pseudoexfoliation glaucoma
normal tension glaucoma
The source of primary infection in most cases of orbital cellulitis is:
Ethmoid sinusitis is the leading risk factor for the development of orbital cellulitis.
When does PXF glaucoma present typically?
presents later in life (in the seventh decade) than primary open angle glaucoma
Which histopathologic variety of meningioma is most commonly seen within the orbit?
Meningothelial meningioma is the most common histopathologic type of meningioma seen within the orbit.
