OCANZ Quiz Tim: Questions & Answers
List and briefly discuss the major causes of visual impairment in Australia.
List and briefly discuss the major causes of visual impairment in developing
countries. - -In Australia
1.AMD cause of 50% of all blindness-less common in developing countries
due to lower life expectancy
2.Glaucoma- 16% of blindness
3.Cataract-11% of blindness
3. Diabetic retinopathy (+ other= 20%)- Most common cause of visual
impairment in working age population
4. 3% uncorrected refractive error
Developing countries -uncorrected refractive errors, cataract- unavailable
surgery, trachoma- river water parasite, glaucoma
-A teenage male attends your practice because he knows he is colour
defective and he has been told that there are some professions where
restrictions are placed on those with a colour vision problem. What advice
would you give this patient? - -Careers with strict restrictions: ARMED
SERVICES
POLICE
AIR TRAFFIC CONTROLER
FIRE SERVICES
Also have restrictions but candidate can work within some divisions:
COMMERCIAL PILOT
MARINE and MARINE PILOT etc;
TRAIN DRIVER
ELECTRICIAL ENGINERING
ELECTRICAL TRADES
COMMERCIAL ARTIST, HOSPITAL LABORATORY TECHNICIANS
PROFFESSIONAL TRANSPORT DRIVER- don't accept protanomaly- do accepy
deuteranomoly
-Indicate the review cycle you would recommend for the following patients
including your rationale behind the review cycle suggested
a) a patient with mild background retinopathy annual review - -annual
review
-Indicate the review cycle you would recommend for the following patients
including your rationale behind the review cycle suggested
,a patient from whom you have just removed a superficial corneal foreign
body - -1/52 to check for signs of infection/inflammation and healing process
-Indicate the review cycle you would recommend for the following patients
including your rationale behind the review cycle suggested
A patient with a branch retinal vein occlusion - -3/12 review- check for '90-
day glaucoma' rubeosis iridis/neovascularistion and macular oedema
-Indicate the review cycle you would recommend for the following patients
including your rationale behind the review cycle suggested
a 6 year old child with hypermetropia and an alternating esotropia wear full
cycloplegic rx - -review in 6 months if no amblyopia
-Indicate the review cycle you would recommend for the following patients
including your rationale behind the review cycle suggested
a patient with optic nerve head drusen - -3 years with medicare?
-Discuss the indications for gonioscopic assessment of a patients' anterior
chamber angle. Describe the structures you will see if the angle is open.
(Open to closed) - -increased IOPs, CAG symptoms, retinal vein/artery
occlusions, pseudoexfoliation/PDS, pxs with glaucoma, anterior uveitis pxs
with inc. IOPs, before dilation if van herick < grade 2
ciliary body, scleral spur, Anterior/ posterior trabecular meshwork, schwalbes
line,
-Central visual field testing has an important role in the diagnosis of
glaucoma.
What type of central field test would you use for a patient who was a
glaucoma suspect?
How would you determine whether the test was reliable?
What information would you concentrate on in the printout to help decide as
to whether the patient had glaucoma? - -Humphreys visual field analyser-
c24-2 full threshold
Fixation losses <20%
False positives <33%
False negatives < 33%
Glaucoma hemifield test, total deviation, pattern deviation type of loss
present- paracentral, arcuate, nasal step, generalised depression, temporal
wedge
, -Discuss the ophthalmic drugs most commonly used for dilation. Include in
your answer their mode of action, duration and side effects. What patients
should not be dilated? - -Tropicamide 1%< anticholinergic, 4-6 hours risk of
CAG, blurred vision,photophobia
Cylopentalate 1%< anticholinergic - 12-24hours risk of CAG, blurred
vision,photophobia
Atropine 1%<
Homatropine 2%<
Pxs with iris fixed IOLs or pxs at risk of angle closure, pxs with known
allergies to mydriatic agents, downs syndrome pxs?
-Define stereopsis. How would you measure stereopsis? What are normal
values? - -the perception of depth produced by the reception in the brain of
visual stimuli from both eyes in combination, combining areas in panums
fusional area.
TNO dependent on age
5 years, 140 seconds:
5 1/2 years, 100 seconds;
6 years, 80 seconds;
7 years, 60 seconds;
9 years, 40 seconds.
-Describe how you would assess whether a patient was suppressing an eye.
- -Check if Vas are equal/ history of
amblyopia/strabismus/surgery/patching/cover test are all useful factors to
consider. Main test of suppression is worths 4 dot- if only 2-3 dots are seen
then one eye is supressed i.e eye with red filter should see green dots, eye
with green filter shot see red dot/ if unavailable can use mallet unit-
polarisation filter means one eye sees 12 and 3 o'clock lines, one eye sees 6
and 9 o'clock lines. If one eye is suppressed only 2 of the four lines will be
visible.
-Dry eye is a common disorder of the tear film caused by tear deficiency or
excessive tear evaporation. What are the major causes of dry eye and how
should dry eye be assessed? - -Causes of dry eye are related to:
• poor tear quality; i.e deficient lipid layer (MGD dysfunction- cause of 50%
of dry eye), deficient mucous layer (e.g stevens-johnson syndrome which
effects goblet cells)