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Mnemonics in Ophthalmology > Refraction > Flashcards

Flashcards in Refraction Deck (16)
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1
Q

After VA failed we check for __(3)__ one after the other (as each fails), and add __(2)__.

A
Counting fingers (CF) and specify distance--> Hand motion (HM) --> Light perception (LP).
We add Sine Correction (SC) or Cum Correction (CC).
2
Q

Light perception (LP) can be subdivided to__(3)__.

A

LPC (creta) - specify direction of light.
LPC (increta) - can’t specify the direction of light.
NLP - no light perception (totally blind)

3
Q

Diopter equals___

Give examples of negative and positive.

A

Diopter = 1/focal point

\+5 = 1/0.2
-10 = 1/-0.1
4
Q

What is the focal point?

A

distance from the lens to a specific point (in meters). Positive after the lens, and negative before it.

5
Q

Diopter - The stronger the lens the______.

A

shorter the distance (more refraction).

6
Q

Cylindrical lens allows______

A

only light form a specific axis to refract onto the retina

7
Q

_____ released by a signal from _____cells encourages the eye to grow in size.

A

Acetylcholine

Amacrine cells

8
Q

Atropine caused the children receiving it a _________

A

Halt in eye growth.

9
Q

Hypermetropia is______

A

small eye due to sharp acuity at too early

10
Q

Accommodation ability is______ related to age.

A

inversely
A 10 y.o. can accommodate +14
A 30 y.o. can accommodate +8

11
Q

Accommodation ability decrease with age is due to _____

and not_______

A

Elasticity decrease and size increases of the lense, and not ciliary muscle weakness.

12
Q

checking for hyperopia requires_____

A

paralysis of the ciliary muscle.

13
Q

Explain PRK (Photo-Refractive Keratectomy).

A

removal of epithelial lining -> polishing stoma -> epithelial lining grows back (after 3 days). Safer but painful.

14
Q

Explain LASIK - (laser-assisted in situ keratomileuses).

A

100 um flap (from epithelial lining and stoma)is cut->polishing stoma -> flap is placed back (no influence to the power of the cornea). No pain and immediate results, but a higher chance of complications.

15
Q

Refractive surgery - cant leave a cornea at less than _____um

A

300

16
Q

A known complication of refractive surgery is_____.

A

Keratoconus