7.2 Refractive Errors

Question 1

Reflective errors related to variation of:

Answer 1

Curvature of cornea
Curvature of lens
Axial length of eyes
Variation in the shape of globe

Question 2

近視
遠視
散光
老化

Answer 2

Myopia
Hyperopia
Astigmatism
Presbyopia

Question 3

Myopia

Answer 3

Cornea too curve
Anterior-posterior diameter too long
Focal point lie short of retina

Concave spherical lens

Question 4

Hyperopia

Answer 4

Cornea too flat
Anterior-posterior diameter too weak
Weak Refracting power focal point behind retina

Convex spherical lens

Question 5

Astigmatism

Answer 5

Uneven curvature of cornea or lens
Globe not round

Cylindrical lens

Question 6

Presbyopia

Answer 6

Harden and sclerotic crystalline lens due to aging
Limit focus on near object

Reading glasses

Question 7

Refractive surgery

Answer 7

LASIK
SMILE

Question 8

SPH
+
-

Answer 8

Sphere: indicate power of lens

+ hyperopia
- myopia

Question 9

CYL axis

Answer 9

Astigmatism:
Cylinder (amount of lens power)
Axis (orientation of astigmatism in degree)

Question 10

Strategies in slowing myopia

Answer 10

1. Myopia control contact lenses
   Stimulate eye growth
2. Overnight orthokeratology
   Temporary

Question 11

Contraindication of refractive surgery

Answer 11

Thin cornea
Presence of autoimmune disease
Presence of glaucoma

Question 12

LASIK vs SMILE

Answer 12

LASIK:
treat myopia, hyperopia, astigmatism
SMILE:
Treat myopia, astigmatism

Question 13

Refractive surgery
Disinfect eye lids with ____
Place a ____ in eye to maintain exposure

Answer 13

Povidone-iodine solution
Speculum

Question 14

Refractive surgery
Post-op: prevent from injury

Answer 14

No eye rubbing
Nighttime protective eye pad
Avoid strenuous activity for 1-2 weeks
No hot-tubs, sauna, swim for 2 weeks
Follow up visit: d1, w1,4, m3, 6, 12

Question 15

Refractive surgery
Complication

Answer 15

Blurred vision
Dry eye
Nighttime glare and halos
Photosensitivity
Flap related complications (flap dislocation)