OSCE 1

Question 1

Pupil distance OC Distance/near

Answer 1

• Ambient lighting
	- Pen torch under my left eye, shown on pX
	- 40cm from pX
	- Px focuses on open eye
	- Measure distance PD via both eyes
	- Reading PD via focus on nose
Record as 65/63

Question 2

Retinoscopy (one eye) instructions

Answer 2

• Clean phoropter
  
  • Set phoropter with Px PDs, and place in position
    • Red/Green on screen (with big E)
    • Dim lights
    “please focus on the green, let me know if I get in the way”
  • Set phoropter with R setting (+1.50D)
    • Set ret with sheath down (diverging lens)
    “I am going to shine a light in your eyes to check your vision”
  • Be 67cm from phoropter and shine ret into chosen eye
    Sweep horizontally, observe motion of reflex light

Question 3

Retinoscopy procedure following reflex

Answer 3

1. Angled reflex line
   Change angles to find the motion with the most SLOW WITH MOTION
   Change angle of ret, to match angle of reflex
   
   2. With motion
      Sweep and increase power of phoropter until reverse and take one step back
      - Change to other angle and adjust cyl
   3. Against motion
      Sweep and increase -cyl power until reverse and take one step back.
      VA is written after Rx

Question 4

VA (from ret in one eye)

Answer 4

• Set Snellen chart near where unaided VA was observed
• Brighten lights
• Occlude one eye
“please read down the chart”
- Terminate at <3 letters read
Record smallest line read plus or take missed/added letters to the nearest 2
6/4.8 is written next to Rx

Question 5

Distance/Near cover test

Answer 5

• Quick unaided VA
“please focus on the letter above where you last read”
“I am going to check your eyes resting state”
- Hold occluder infront of left eye for 3s
- Remove and observe right eye
- Hold occluder infront of right eye for 3s
- Remove and observe left eye
• Record tropia, motion for eye reflex (eso, exo, ortho)
- Hold occluder infront of left eye for 3s
- Swap quickly to right eye for 3s
- Observe eye that is about to be uncovered
• Record phoria / preform phi test
REPEAT ABOVE WITH PX HOLDING READING CHART

Question 6

Cover test recording

Answer 6

Orthophoria: no motion between eyes “Theta sign”
Heterophoria: eye turn with cover “eso/exop”
Heterotropia: constant eye turn “eso/exot R/LE”
With glasses: “C Rx” (with a line on top)
Without glasses: “S Rx” (with a line on top)
Eg. D: Exop S Rx

Question 7

Phi test:

Answer 7

During alternating cover test “is target moving with/against cover”
With = Exop/Exot
Against = Esop/Esot
None = Ortho

Question 8

MOTILITY

Answer 8

” focus on big H, keep head still”
“ lemme know if there is pain/double vision”
Swing target in HH pattern

Question 9

Recording motility

Answer 9

Tick HH where motion is fine
Cross + (L/R), (Muscle failure)
“ full and smooth, - pain/diplopia)

Question 10

Relative afferent pupil test:

Answer 10

• Focus on white dot on screen, din lights
“lemme know if I get in the way, imma shine some light”
- Shine light close/inferior into left eye for 3s
- Quickly swap to right eye for 3s
Look for difference in pupil size.
If good, record as -RAPD

Question 11

Direct/consensual response

Answer 11

• Focus on white dot, dim lights
“ lemme know if I get in the way”
- Shine light into right pupil
Note RE constriction (direct)
- Remove light for 3s then shine again into right eye
Note LE constriction (consensual)
- Repeat in LE
Record as PERRL (pupils are equal, round, reactive), and DCN (Direct, consensual, near response)
Only include Accomodation (PERRLA) is PERRL is abnormal