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1. Photo of bones of cranial base.
a. Name the foraminae/meati labelled A to E (5)
Optic Canal, Foramen Ovale, Foramen Rotundum, Foramen Spinosum,
Internal Acoustic Meatus
b. What structures pass through each of these? (5)
2. 32 year old lady with Neurofibromatosis 2 and epilepsy. Has back lumps
which biopsy shows schwannoma. She complaint of loss of vision and enucleation
was done. Histology picture:Shown 2 histology photos
a. What structures are arrowed 1, 2 and 3? (3)
b. What cell type is 1 and what is the site of origin in the orbit? (2)
c. What is the diagnosis (1)
Optic nerve sheath Meningioma
d. Four associations of NF-2 (4)
3. Young lady with lethargy, fever, joint pains, weight loss, thinning of
hair. Blood results shows FBC (pancytopenia), raised ESR, renal panel with
raised Creatinine, ANA and RF positive
a. List the 4 key types of immunological hypersensitivity reactions of Gell and
Coombs (4)
b. What are the 4 main abnormalities? (2)
c. What is the likely diagnosis (1)
d. Name two other tests you should do? (2)
e. Name one fatal complication of this disease (1)
4. Optics
a. When considering refraction by an eye, four catopric (Purkinje- Sanson)
images are formed. Why are there four? (1)
b. Draw a diagram to show the position of these images as seen by an observer
(4)
c. One of these images is inverted. Which one and why? (2)
d. One of these images is routinely used in
clinical practice. Which image and give 2 examples of its use? (2)
5: Optics
a. Express the distance spectacle prescription in positive cylinder form and
describe the type of refractive error in each eye (4)
b. What symptom may arise if this person has
spectacles dispensed? (1)
c. Give three options which may help reduce this problem for the patient (3)
d. Give two methods by which this patient’s cylindrical correction could be
reduced at the time of right cataract surgery? (2 marks)
6. Optics
a. What type of lenses form the constituent parts of a Maddox Rod? (2)
b. Draw a ray diagram to indicate how a Maddox rod produced the image seen by a
patient (4)
c. A patient using a Maddox rod in front of the right eye sees the following
images. In each case how would the motility be described in ophthalmic terms?
(3)
- 1: Right exophoria. 2: orthophoria. 3: Right hypophoria
d. What adaptation to this test should be made for a patient who is red/green
colour blind? (1)
7. Optics
a. Draw two ray diagrams to demonstrate how increasing the back vertex distance
changes the power of a plus lens to produce emmetropia (6)
b. What is the minimum power of lens before the back vertex distance needs to be
documented in a prescription? (1)
c. If a convex lens is moved further from the eye, what is the impact on the
effectivity of the lens? (1)
d. An aphakic patient requires 9 diopterlens at a back vertex distance of 10mm.
What power of contact lens is required? Show how you reach your answer rounded
up or down to the nearest 0.25 diopters.
8.
a. Write short notes on Sherrington’s law of reciprocal innervations, as it
applies to the actions of the extraocular muscles. You should provide an example
and define any terms you use. (4)
b. The HESS or Less screen tests are used to assess patients with incomitant
strabismus. Complete the HESS charts below illustrating the likely abnormalities
for a patient with a recent onset right abducens nerve palsy (6)
9. ERG question
7 Graphs of ERGs shown (control and affected eye): Pattern ERG, on/off cone,
dark adaptation early and late, light adaptation, S cone
Of the seven tests performed, using the letters above each of the tests (A-G),
which tests do the following: (4)
o Tests macular function
o Tests the rod pathway exclusively
o Determines the combined response of both the rod and cone pathways
o Is the only one of the seven tests that may be affected by optic neuropathy
Regarding the ERGs in this patient, one noticeable abnormality is the bright
white flash test (Dark adapted 11.5cd s/m2) in which the positive B wave does
not achieve the same voltage deflection as the negative a wave. This is known as
‘negative ERG’. Consider the following questions:
1. What does this tell us about the site of retinal abnormality in this patient?
(1)
2. Give two acquired causes of a ‘negative ERG’ (2)
3. Give two inherited disorders that characteristically cause a ‘negative ERG’
4. Tests F examines specific retinal cells. What is the abnormality in the
patient (1)
10. Photos of (X) B-scan/A-scan (Y)
a. What are the investigations X and Y? (2)
b. List 3 clinical situations in which investigation X is useful (3)
c. Describe the abnormalities seen in X (2)
d. What additional information is given in Y? (2)
e. What is the likely diagnosis? (1)
- Retinal detachment
11. HVF showing dense right superior temporal
visual field defect and scattered left superior temporal field defects
a. This is a Humphrey visual field test. What type of field test is this? (1)
b. What does 24/2 mean? (2)
c. Has this test been performed reliably? Explain your answer (2)
d. Describe the abnormalities present (2)
e. Where is the lesion and give 2 possible causes (3)
12. Biostatistics
a. Research studies often designed to test a hypothesis. A new published paper
seeks to assess the IOP lowering effects of a new drug (Glucocure) when compared
to the standard medication (Timolol). Explain the meaning of the following terms
in this context:
i. Null hypothesis (2)
ii. Alternate hypothesis (2)
b. 100 patients with raised IOP recruited into study. Patients randomly
allocated into Glacocure or Timolol treatment groups. 50 were given glucocurebd
for 3 months, and 50 timololbd for 3 months. IOP measured at entry and after 3
months. Neither the investigators or patients knew the drug they were using.
What type of study design have the investigators used? Explain (2)
c. Results states that mean reduction in IOP in glucocure group was 8.3mmHg (95%
confidence interval 6.5-10.1mmHg) and in timolol group 6.8mmHg (95% CI
5.5-7.7mmHg). Would the investigators be justified in claiming that Glucocure
was a effective IOP lowering agent than Timolol? Explain (2)
d. The mean IOP at entry to study group for Glucocure was 27.5mmHg and 28.9mmHg
in Timolol group. This difference in IOP had a p value of 0.11 (student
t test). Explain the significance of this p value (2)
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