Key points 5

Question 1

The most common cause of acute, painful enlargement of the lacrimal gland is

Answer 1

Acute dacryoadenitis is most often caused by ascending staphylococcal infection and is associated with a purulent conjunctival discharge. Viral dacryoadenitis is frequently painless.

Question 2

Which factors are Most important to the success of macular hole surgery?

Answer 2

Vitrectomy and ILM peeling are important in eliminating antero-posterior and tractional forces respectively, which are central to the pathophysiology of macular holes. Likewise, gas tamponade is important in creating a scaffold for hole closure. The role of posturing, however, is far less certain and remains a point of contention among surgeons. It is certainly the least important operative factor in the list above.

Question 3

What are some fundus features of Eales Disease

Answer 3

Eales disease is an uncommon, bilateral, idiopathic, occlusive condition characterized by peripheral periphlebeitis and neovascularisation. It is more common in young Asian males and there is an association with tuberculoprotein hypersensitivity.

Question 4

A child with congenital nystagmus has a null zone in right gaze and severe left head turn. Surgical intervention for the patient might include:

Answer 4

The goal of muscle surgery in congenital nystagmus is to move the null zone to primary position. This is done by shifting the resting position out of primary position toward the direction opposite to the null zone. Then, to obtain primary gaze, the child will need to innervate ocular muscles as if gaze were toward the null zone.

Question 5

A 48-year-old woman presents with reduced right vision. On examination there is 360-degree peripheral choroidal effusion in the right eye. There is no past ocular history apart from hypermetropia. There is no tobacco dust and the IOP is 18mmHg.

What is the most appropriate management?

Answer 5

The patient in the question above has uveal effusion syndrome which is treated by sclerotomy down to the choroid to allow egress of the proteinaceous fluid. This is repeated in all four quadrants.

Question 6

What is the most common site of retinoblastoma spread outside the eye?

Answer 6

Direct spread into the optic nerve and CNS is most common. Bone metastasis is seen in over half of metastatic cases. Lymph node metastases are the second most common type.

Question 7

The single most important physical property of perfluorocarbon liquids rendering them useful as vitreous substitutes in vitreoretinal surgery is their:

Answer 7

The high specific gravity of perfluorocarbon liquids renders them heavier than water and makes them a useful addition to the vitreoretinal armamentarium. They can steamroll giant retinal tears flat, act as third hands in complicated surgery, and effect drainage of subretinal fluid through breaks in the far periphery, obviating the need for drainage retinotomies.

Question 8

What are some disadvantages of using perfluorocarbon liquids in VR surgery?

Answer 8

they are not tolerated by the retina for >24 to 48 hours (histopathology shows compression of the retina) and they are not tolerated by anterior chamber structures at all.

Question 9

From anterior to posterior the medial orbital wall is composed of:

Answer 9

maxilla, lacrimal bone, ethmoid, sphenoid

Question 10

Which is the most common type of collagen in the sclera?

Answer 10

Type 1 collagen

Question 11

Systemic side-effects of beta-adrenergic blockade include

Answer 11

central nervous system depression
syncope
bradycardia

Question 12

Where is the lesion in dissociated divergence nystagmus?

Answer 12

posterior fossa lesions.

Question 13

Where is the lesion in Downbeat nystagmus

Answer 13

craniocervical junction tumours, Wernicke’s, drugs (e.g. alcohol, lithium, phenytoin) and paraneoplastic syndromes (e.g. small cell lung cancer)

Question 14

Where is the lesion in Upbeat nystagmus?

Answer 14

posterior fossa lesions, drugs and Wernicke’s.

Question 15

Where is the lesion in See Saw nystagmus

Answer 15

parasellar/chiasmal lesions

Question 16

Where is the lesion in gaze evoked nystagmus?

Answer 16

physiological, congenital motor nystagmus, posterior fossa (brainstem/cerebellar)

Question 17

What is the diagnostic criteria for Behcet’s disease?

Answer 17

oral aphthous ulcers (any shape, size, or number at least 3 times in any 12 months period) along with 2 out of the following 4 hallmark symptoms:
genital ulcers: including anal ulcers and spots in the genital region and swollen testicles or epididymitis in men
skin lesions: papulo-pustules, folliculitis, erythema nodosum, pyoderma gangrenosum, acne in post-adolescents not on corticosteroids
eye inflammation: iritis, uveitis, retinal vasculitis, cells in the vitreous
pathergy reaction: papule >2 mm diameter 24-48 hrs or more after needle-prick. The pathergy test has a specificity of 95% to 100%, but the results are often negative in American and European patients.

Question 18

Arteries vs Veins: Behcet disease and sarcoid which ones are involved?

Answer 18

Vasculitis in Behcet’s disease involves both arteries and veins, by contrast to sarcoid for example where ocular vasculitis only involves the veins (periphlebitis).

Question 19

In which condition do we get crossed fibres at the chiasm?

Answer 19

tyrosinase-negative albinism

Question 20

What are some ocular features of tyrosine negative albinism?

Answer 20

Crossed ON fibres at chiasm
V/A less than 6/60 due to foveal hypoplasia
Squints
Nystagmus
High refractive errors

Question 21

What are the features of intermittent exotropia?

Answer 21

Amblyopia is not a feature of intermittent XT because the deviation is intermittent. Most patients with truly intermittent exotropia have excellent stereoacuity. High accommodative AC/A ratios may develop as a fusional mechanism for near work. The deviation in intermittent exotropia is highly variable and sensitive to external stimuli (stress, alcohol, tiredness). Bright light typically causes reflex closure of the deviating eye.

Question 22

What are the duration of VR gases?

Answer 22

SF6: 10-14 days
C2F6: 30-35 days
C3F8: 55-65 days

Question 23

What are 2 autosomal recessive conditions which present with albinism?

Answer 23

Hemansky-Pudlak and Chediak-Higashi

Question 24

What blood test is abnormal in Hermansky Pudlak disease?

Answer 24

Abnormal platelets causing diathesis

Question 25

What blood test is abnormal in Chediak Higashi syndrome?

Answer 25

leucocytes that cannot release enzymes from lysosomes causing recurrent pyogenic infections.

Question 26

Which visual field best corresponds to a patient with acute papilloedema?

Answer 26

the visual field generally shows only an enlargement of the blind spot. The earliest loss of visual field in chronic papilloedema is typically in the inferior nasal quadrant.

Question 27

What are the ERG findings in Birdshot Chorioretinopathy?

Answer 27

reduced b wave amplitude, decreased oscillatory potential, and delay in implicit time of 30Hz flicker (which is the most sensitive change).

Question 28

What are ocular features of Lawrence Moon syndrome?

Answer 28

Lawrence-Moon syndrome is associated with retinal pigmentary changes, spastic paraplegia, hypogonadism and mental retardation.

Question 29

Which type of basal cell carcinoma carries the worst prognosis?

Answer 29

The fibrosing (or sclerosing) type of BCC is also known as morpheaform. This pattern features strands of tumor cells infiltrating out from the central, clinically apparent lesion. Therefore, it is much more difficult to define the margins of the lesion. It is also less responsive to radiation therapy. The other forms listed above tend to be more localised.

Question 30

A 4-year-old child is under paediatricians with aminoaciduria. There is developmental delay, hypotonia, abnormal skull shape and lamellar cataract bilaterally. What is the most likely diagnosis?

Answer 30

Lowe syndrome is associated with: X linked recessive inheritance mental handicap Fanconi syndrome of proximal renal tubules muscular hypotonia congenital cataract microphakia posterior lenticonus

Question 31

What proportion of patients with sub-arachnoid haemorrhage have Terson's syndrome?

Answer 31

33%

Question 32

What is the CSMO criteria?

Answer 32

retinal thickening with 500 um of the fovea hard exudates within 500 um of the fovea with associated retinal thickening retinal thickening 1 disc area in size any part of which is within 1 disc diamter of the fovea

Question 33

Which of the following syndromes is characterised by an anti-mongoloid slant of the palpebral fissure:

Answer 33

Treacher Collins is characterised by: autosomal dominant clefting syndrome hypoplasia of the mid-face pseudocolobomas of the eyelids downward angle to the lateral canthi micrognothia dental anomalies ear anomalies: small and malformed with conductive hearing loss

Question 34

Which of the following is the most appropriate surgical treatment for acquired sixth nerve paresis with poor residual lateral rectus function:

Answer 34

The most widely accepted approach in sixth nerve palsy is a muscle-splitting operation utilising half of the superior and inferior rectus muscles in a transposition laterally (Jensen's procedure).

Question 35

In fluorescein angiography, pseudoautoflourescence occurs due to:

Answer 35

Pseudoautoflourescence occurs due to overlap in the spectral transmission of the excitation and barrier filters, meaning that some blue reflected light does pass through the barrier and appear as fluorescence.

Question 36

What is the choice of stain for Acanthamoeba

Answer 36

Calcofluor white is the stain of choice for Acanthamoeba and requires fluorescence microscopy.

Question 37

Causes of granulomatous uveitis?

Answer 37

syphilis (VDRL), sarcoid (ACE), TB (Tuberculin/purified protein derivative/PPD) among other aetiologies.

Question 38

The prevalence of HLA-B27 in the UK general population is approximately:

Answer 38

estimated at 8%.

Question 39

ERG findings in LCA

Answer 39

Leber's congenital amaurosis is a disorder of congenital blindness that often presents with a normal appearing fundus in the neonatal period. However, an ERG done at this time will show a severely attenuated or extinguished ERG.

Question 40

Features of direct CCF?

Answer 40

arterio-venous communication caused by communication between ICA and cavernous sinus (c.f. meningeal branches of ICA for indirect) trauma responsible for 75% of cases - others spontaenous from age-related arteriosclerosis presents days to weeks after head injury high flow shunt blood flows anteriorly into ophthalmic veins raised episcleral venous pressure ocular congestion pulsatile proptosis - bruit and thrill anterior segment ischaemia ophthalmoplegia disc swelling, retinal haemorrhages open angle glaucoma not life-threatening but sight-threatening Treatment: await spontaenous thrombosis OR balloon occlusion of fistula

Question 41

The b wave of the ERG is formed by:

Answer 41

Bipolar cells

Question 42

The extraocular muscle with the shortest length of active muscle belly is the:

Answer 42

The belly of the superior oblique is approximately 32 mm (the others are 37 to 40 mm)

Question 43

What is the Bonferroni correction?

Answer 43

the Bonferroni correction is used to reduce the chance of a Type I error

Question 44

A variant of Guillain-Barre syndrome that involves mainly the brainstem and cranial nerves is known as:

Answer 44

Miller Fisher syndrome, which is a variant of Guillan-Barre syndrome, is characterised by: ophthalmoplegia ataxia areflexia descending paralysis (as opposed to GBS where it is ascending) positive anti-GQ1b antibodies in 90% treatment by plasmapheresis and iv immunoglobulin

Question 45

Name some ocular conditions with cataracts associated with urinary features

Answer 45

galactosaemia: reducing substance in urine Lowe's: aminoaciduria Fabry's: sediments Wilson's: copper Alport's: blood (glomerulonephritis)

Question 46

Features of VHL

Answer 46

autosomal dominant inheritence retinal capillary haemangioma CNS haemangioma cysts of kidneys, pancreas and ovaries renal cell carcinoma phaeochormocytoma

Question 47

What is the Quickert procedure?

Answer 47

combines horizontal lid shortening with a transverse lid split and everting sutures, and would be the procedure of choice in this case.

Question 48

What is the Wies procedure

Answer 48

involves a horizontal lid split and everting sutures, but it does not address the issue of horizontal lid laxity.

Question 49

What is the Jones procedure

Answer 49

involves plication of the lower lid retractors, but once again, unless combined with another procedure, the Jones procedure does not address the issue of horizontal lid laxity

Question 50

When is tarsal fracture done?

Answer 50

reserved for cicatricial entropion

Question 51

Which arteries make up the circle of willis

Answer 51

Anterior cerebral arteries Anterior communicating artery Internal carotid arteries Posterior cerebral arteries Posterior communicating arteries

Question 52

Features of Goldenhar syndrome

Answer 52

preauricular appendages aural fistulas maxillary or mandibular hypoplasia hemifacial microsomia vertebral deformities lid coloboma Duane's syndrome limbal dermoids sensorineural deafness

Question 53

The finding most frequently associated with degenerative retinoschisis is:

Answer 53

peripheral cystoid degeneration

Question 54

A 7-year-old boy presents via his opticians with visual acuity of 6/6 right eye; 6/15 left eye. Motility is full, and there is no apparent tropia on cover-uncover testing. The child has stereoacuity of 120 seconds of arc. Distance Worth four-dot testing reveals fusion. Convergence and divergence amplitudes are normal at distance. There is no movement detected when a 4-prism dioptre is placed over the left eye. What additional finding is MOST likely:

Answer 54

The clinical features of mild amblyopia, mildly impaired stereopsis, peripheral fusion, eccentric fixation with a central suppression scotoma are typical of a microtropia (the tropia is either too small to detect or does not exist because of parafoveal fixation and anomalous retinal correspondence). Microtropia is most common in the setting of anisometropia, usually hypermetropic anisometropia. Microtropia can also occur after (almost) successful strabismus surgery where the child controls to a microtropia.

Question 55

Which of the following features in the history of a patient with a lacrimal gland mass is MOST important in determining aetiology?

Answer 55

The most helpful features in discriminating lacrimal gland masses are: pain: more typical of acute inflammatory, infectious, or malignant lesions onset: slow onset suggests a benign lesion, acute suggests inflammation or malignancy bony erosion: favours a malignant lesion