Final: Accommodation Dysfunction Flashcards
3 types of accommodation insufficiencies. Explain them.
1) Ill-sustained - dramatic decrease in performance over time
2) Paralysis
3) Unequal accommodation
Duane’s Accommodative Classifications (3)
1) Accommodative Insufficiency
2) Accommodative Excess
3) Accommodative Infacility
What do you need to make sure you do with Donders Amp testing? What can you do to diminish inaccuracies?
Make accurate measurements.
Run through a -4.00 lens to make inaccuracies less.
Describe the Alternative Pull Away Method for testing Accommodative amplitude. What can give inaccuracies and by how much?
Start with target really close to pt. and pull back until target just readable. Relative Size Magnification can give overestimation of amplitude up to 2.00D.
Hofstetters Formula for average Amp.
18 - (1/3) Age
Hofstetters Formula for minimum amp.
15 - (1/4) age
What does facility testing test?
Ability to stimulate and relax accommodation. Recorded in cycles per minute.
How would you record if patient cleared 24 times and failed on minus lenses at 55 seconds?
12 cycles, failed (-) @ 55
How would you record if patient cleared 24 times in 60 seconds and did not fail the testing
12 cpm
Expected cpm for 6 year old
5.5 cpm +/- 2.5
Expected cpm of 7 year old
6.5 cpm +/- 2.0
Expected cpm for 8-12 year old
7.0 cpm +/- 2.5
Expected cpm 13-30 years old
11 cpm +/- 5.0
How do you test MEM (near ret Lag)? What results would we expect?
Have MEM card attached to retinoscope. Have them read at 40 cm for adults and Harmons distance for children. Quickly drop in loose lenses and neutralize. We would expect +0.25 to +0.50.
Accommodative Insufficiency Symptoms (6)
1) Blurred Vision
2) Headache
3) Eyestrain
4) Reading Problems like comprehension, avoidance of reading, and movement of print when reading.
5) Pulling sensation around eyes
6) Fatigue and Sleepiness
Accommodative Insufficiency Signs (Direct measurements)
High UFCC
High MEM
Reduced amplitude of accommodation
Difficulty clearing -2.00D with monocular facility
Accommodative Insufficiency Signs (Indirect measurements)
Reduced PRA
Difficulty clearing -2.00D with binocular facility
Low BO reserves at near
High FCC
Accommodative Excess Symptoms
When relating to near tasks:
Blurred vision, worse after reading/near work
Headaches
Eyestrain
Difficulty focusing from near to far
Photophobia- due to ciliary bodies getting tired, send pain signal.
Accommodative Excess Signs (Direct measurements)
Difficulty clearing +2.00D on mono. accom. facility
Low lag to lead on UFCC/MEM
Accommodative Excess Signs (Indirect measurements)
Low NRA
Difficulty clearing +2.00D on bino. accom. facility
Low FCC
Low BI reserves at near
What would we see if we saw a Pseudo CI? What signals a pseudo CI? How do we resolve?
High exo at near with low BO reserves and low amplitude of accommodation.
Poor results on all tests that stimulate accommodation is what signals that it may be Pseudo CI.
If given plus, the exophoric at near will decrease (unlike what it is predicted).
What would vision therapy do for patient who has accommodation excess?
Make patient be able to accept more plus
What would vision therapy do for patient who has accommodation insufficiency?
Make patient try to work on accepting minus.
