Key points 10 Flashcards
Which prognostic factor favors an excellent outcome after surgery for rhegmatogenous retinal detachment:
RD secondary to dialysis
small round holes
detachments with demarcation lines (chronic)
detachments with minimal sub-retinal fluid
Generalised vs ocular myasthenia features
more auto-immune disease correlations e.g. Graves
more commonly associated with thymoma
more likely to be anti-ACh receptor positive
more likely to have positive nerve conduction studies
more likely to have remission induced by thymectomy
A 7-year-old boy returns 1 day after bilateral lateral rectus recessions for intermittent exotropia. He measures 8 PD of consecutive esotropia and has diplopia. The parents are concerned.
Which of the following management options is MOST appropriate:
An immediate overcorrection of 8 to 12 PD is a desirable result. Often, over the first or second postoperative week, the effect of the surgery will lessen and the eyes will straighten.
A 78-year old man is diagnosed with acute retinal necrosis. PCR of a vitreous sample is most likely to reveal:
ARN occurs in otherwise healthy individuals of all ages. In younger patients, HSV tends to be the causative organism whereas in older patients (over 50) the cause tends to be varicella zoster virus.
Which investigation is contraindicated in individuals with an allergy to shellfish?
ICG
What are the results from the DRS study at 3 years in patients with mild NVD, severe NVD +/- haem and NVE.
Mild NVD with Hg: 26% severe vision loss, reduced to 4% with PRP
Severe NVD without Hg: 26%, reduced to 9% with PRP
Severe NVD with Hg: 37%, reduced to 20% with PRP
Severe NVE with Hg: 30%, reduced to 7% with PRP
what are the features of atypical CHRPE?
bilateral, widely separated lesions seen throughout both fundi
spinde-shaped lesions
lesions hypopigmentation at one margin
Definition of true congenital glaucoma?
(40%) which develops in utero
Definition of Infantile glaucoma
(55%) which develops before the third birthday
Definition of Juvenile Glaucoma?
(5%) develops after the third birthday but before the age of 16 years
Causes of negative ERG
This is the result of disruption in communication between the photoreceptors and the bipolar cells.
Causes of a negative ERG include:
X-linked retinoschisis
congenital stationary night blindness (usually in scotopic ERG initially)
central retinal artery occlusions
What are junctional naevi?
flat or slighly elevated and are comprised of nests of nevus cells in the basal epithelial layer. They have the greatest potential for malignant transformation to melanoma by comparison to intradermal nevi and compound nevi.
Indications for therapeutic intervention for optic nerve glioma include
intracranial spread
rapid growth simulating a malignant variety
loss of functional vision
What are Herbert’s pits?
They are the scarred remnants of inflammatory nodules on the limbus.
What are hassall Henle warts?
nodular excrescences on the posterior surface of Descemet’s membrane found in Fuch’s dystrophy.
What is the most common cause of painless bilateral enlargement of the lacrimal gland.
Sarcoidosis
What is the treatment of choice for uncomplicated acute retinal pigment epitheliitis (Krill’s disease)?
Krill’s disease usually subsides without any treatment over 2 to 3 months.
What is cyclic esotropia?
The cycle is typically 48 hours long: 1 day of esotropia, and 1 day of orthotropia. Many experts believe that this is a variety of accommodative esotropia, with many features similar to it.
Which condition is closely associated with multiple evanescent white dot syndrome:
may form part of a spectrum of disease that includes acute idiopathic blind spot enlargement, acute zonal occult outer retinopathy and acute macular neuroretinopathy.
Which study, conducted in the 1970s defined diabetic retinopathy risk factors and confirmed the benefits of extensive scatter retinal photocoagulation for high-risk disease:
DRS
What are the features of Weil Marchesani syndrome.
AD inheritence
mental retardation
short stubby fingers
downward lens subluxation
microspherophakia
What are the features of iridocorneal endothelial syndrome?
abnormal proliferation of corneal endothelial cells, which invade anterior segment structures including the trabecular meshwork and the iris, resulting in corneal endothelial dysfunction, iris abnormalities and secondary glaucoma.
What are the 3 recognised clinical variants of ICE?
Progressive iris atrophy: severe iris changes including atrophy, corectopia and pseudopolycoria
Cogan-Reese syndrome: diffuse iris naevus covering the anterior iris or iris nodules with or without iris atrophy
Chandler syndrome: hammered-silver corneal endothelial abnormalities with corneal decompensation
Irrigation of PMMA IOLs just before insertion is intended to
PMMA lenses may pick up static charges that attract dust and debris when opened. Therefore the lens may be rinsed with balanced salt solution before insertion.
What is normal steroacuity in various parts of the vision?
Centrally: 20-40 seconds of arc
Peripherally: 200 seconds of arc
Maximal at 0.25 degrees off dead-centre of the fovea
Minimal beyond 15 degrees of eccentricity
What are fundus features of FEVR?
failure of vascularisation of the temporal retinal periphery, similar to that seen in ROP but in the absence of low birth weight or prematurity. Complications include tractional retinal detachment and massive sub-retinal exudation. Prognosis is generally poor.
The triad of adenoma sebaceum, mental retardation, and seizures is considered pathognomonic for
tuberous sclerosis
What are the features of tuberous sclerosis?
cerebral cortical tubers, after which the disease is named
astrocytic hamartomas of retina and brain (often calcified)
seizures
mental retardation
renal angiomyolipomas
adenoma sebaceum
cafe-au-lait spots
ash leaf depigmentation
shagreen patches
periungual fibromas
Where is lattice dystrophy commonly seen?
common superiorly rather than inferiorly, and more common temporally than nasally.
When is enucleation performed?
large tumours (too large to be treated by other means e.g. brachytherapy and radiotherapy)
tumours extending to the optic nerve
eyes with severe complications e.g. painful secondary glaucoma, RD’s, etc.
What is normal stereoacuity?
Normal stereoacuity is approximately 60 seconds of arc,
