OCANZ Written April 2017 Exam Questions &
Answers
25 year old with stargardts disease requests assistance with reading tasks,
lighting at work and travel, which of the following professional below will
assist him-
occuptational therapist,
orientation instructor,
phsycologist & GMP,
Physiotherapist & Rehab,
Social worker & Ophthalmologist - -
-What is Stargardt disease - -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 - -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 - -c/ Discuss findings with GP
before prescribing Rx,
-The main cause of amblyopia in a child: anisometropia >2, accommodative
eso, intermittent exo - -anisometropia >2,
-Which of the following can match Illuminant c: Incandescent, Halogen,
Flourescent, sodium - -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 - -d/ Gonio
-What is Kolleners rule in relation to colour vision? - -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 - -Optic
neuritis
-Lissamine green; what does it stain? - -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? - -no
-What is prenticies rule? - -P (prism dioptres =c (decentration in cm) x
F(power of lens in dioptres)
-What is the most preventable cause of AMD? - -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 - -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 - -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? - -improve lens hygeine
Increase lens replacement frequency