OCANZ Written Exam 2024 | OCANZ
Exam Update Latest 2024 Questions and
Correct Answers Rated A+
What is Stargardt disease -ANSWER-is the most common form of
inherited juvenile macular degeneration.
Wife calls requesting details on husbands eye test. Do you: get verbal
consent, refuse call, get written consent -ANSWER-get written
consent
Diabetic recently diagnosed unstable. Refraction reveals significant
myopic shift compared to last visit 12 months ago. Which is the most
appropriate course of action:
a/ prescribe specs & report to GP
b/ Refer to Ophthalmologist,
c/ Discuss findings with GP before prescribing Rx,
d/ Obtain info on current blood glucose levels -ANSWER-c/ Discuss
findings with GP before prescribing Rx,
The main cause of amblyopia in a child: anisometropia >2,
accommodative eso, intermittent exo -ANSWER-anisometropia >2,
Which of the following can match Illuminant c: Incandescent, Halogen,
Flourescent, sodium -ANSWER-Fluorescent
25 years old enquiring her suitability for laser refractive surgery. Which
of the following is NOT essential pre-operatively:
a/ Tonometry,
b/ Tear film stability
,c/ pupil size,
d/ Gonio -ANSWER-d/ Gonio
What is Kolleners rule in relation to colour vision? -ANSWER-outer
retinal diseases and media changes result in blue-yellow color defects
inner retina, optic nerve, visual pathway, and visual cortex will result in
red-green defects.
(increased susceptibility of S-cones and rods to ischaemia and
oxidative damage, although S-cone loss is more noticeable due to
their lower density and their higher metabolic rate) (Kollners rule,
retinal disease will give a blue yellow defect and optic nerve disease
will give a red green defect but the exceptions are glaucoma which will
give a blue yellow defect and central cone degeneration which will
give a red green defect)
Which causes a red defect- red cap test: optic neuritis, Amd -
ANSWER-Optic neuritis
Lissamine green; what does it stain? -ANSWER-Lissamine green
stains dead and degenerate cells, yet does not stain healthy epithelial
cells.
(NaFl permeates into the intercellular space associated with any
epithelial cellular disruption)
Is gonio indicated with Hyphaema? -ANSWER-no
What is prenticies rule? -ANSWER-P (prism dioptres =c (decentration
in cm) x F(power of lens in dioptres)
What is the most preventable cause of AMD? -ANSWER-Smoking
,15 years old attends eye examination, best Va's R6/6, L 6/24 (told
ambloypic). Which occuptation should he NOT pursue:
a/ Train driver,
B/ construction worker,
c/ Electrician,
d/ Dentist -ANSWER-a/ Train driver
RGP fit with lens riding high and bubbles underneath. What is the
bubbles underneath- name? What is the cause? How would you
change the fit? Rewrite the prescription, base curve/power/diameter
according to change in fit. 0.05 base curve change the rx by 0.25,
0.5mm diam change etc...all the rules of thumb -ANSWER-DimpleVeil
RGP too steep - reduce total diameter, flatten
Change BOZR by 0.1mm then change power of 0.50D to keep NaFL
pattern?
Increase TD by 0.1mm then flatten BOZR by 0.05mm
Picture of GPC, differential diagnosis, treatment
Treatment method for GPC? -ANSWER-improve lens hygeine
Increase lens replacement frequency
DD if possible
Reduce modulus of lens material (Swap to hydrogel lens, be aware
more difficult to handle)
Manage lid margin disease
If sever - topical Mast cell stabalisers
Colour vision: What careers can you do if you have a defect?
What is the fail criterion for D15.
, What test would you do to confirm ishihara? -ANSWER-Fail criterion is
2 or more diagonal crossings
D15 can classify but not grade severity
63 year old elderly woman with purple loss in vision for past 3 weeks,
she is experiencing jaw claudication.
a) What is your diagnosis?
b)What is your systemic and optometric management?
c) Patients prognosis? -ANSWER-GCA
evaluating visual acuity, pupils (looking for a relative afferent defect),
intraocular pressures, anterior segment examination, motility
examination (looking for ocular misalignment and/or evidence of
cranial neuropathies), and a dilated fundus examination (evaluating for
signs of optic nerve or retinal ischemia)
Visual fields testing
ESR (erythrocyte sedimentation rate), high then indicated inflamation
CRP (C reactive protein) - produced by liver with inflamation
platelets
temporal artery biopsy
prog good if no CRAO or AAION, better prognosis the sooenr steroids
are started
Patient burnt with laser. Management -ANSWER-NSAID or Anti VEGF
depending on severity
Name of drops post cataract and percentages post op. -ANSWER-
Different ophthals do different things. Ideally you want an antibiotic eg
chloramphenicol for 1 month qid and a steroid eg maxidex for 1 month