Retinoscopy/Refraction Goals Flashcards
Tendency for the refractive state of the eye to change close to plano.
Emmetropization
What is considered emmetrope?
+0.50D to -1.00D
What is the average refraction of a newborn?
+2.00
What percent of newborns are between Plano and +4.00
88%
What percent newborns have astigmatism?
30%
What percent newborns have astigmatism?
30%
How does the eye shape change during process of emmetropization?
eye lengthens axially
What structural changes happen in eye during emmetropization?
-Crystalline lens thickens in infancy and school years but gets flatter
-Corneal power decreases
-Has axial growth
When does the majority of emmetropization occur?
3-9 months
What is the best predictor of emmetropization?
cycloplegia refraction
What is the best predictor of emmetropization?
cycloplegia refraction
Are large amounts of astigmatism common in children less than 3 years old?
Yes, 30% are 1D astigmatic
Is against the rule (ATR) or with the rule (WTR) more common in children under 3?
Against the rule
At what age does cylinder prescription not change as much?
4 to 5 year olds. Reaches adults levels, think about prescribing.
What is the prevalence of vision disorders (astigmatism) in hispanics according to “Prevalence Vision Disorders Head Start”?
11.1%
What is the prevalence of vision disorders (astigmatism) in American Indians according to “Prevalence Vision Disorders Head Start”?
4.28%
Ethnicity with highest hyperopia prescriptions in children in LA study. What is average prescription?
White
+2.1D
Ethnicity with lowest hyperopia prescriptions in children in LA study. What is average prescription?
Asian, 0.83D
In age group 5-7, what is the typical refractive error?
+0.50 to +3.00
If you are examining a 5 or 6 year old and they are Plano or +0.25, what would you expect when they get older?
They would be myopes. Females become myopic earlier than males.
If you are examining a 5 or 6 year old and they are Plano or +0.25, what would you expect when they get older?
They would be myopes. Females become myopic earlier than males.
Describe Mohindra near retinoscopy
A near retinoscopy technique for assessment of distance refractive error. In completely dark room. Infant fixate at retinoscope at 50 cm. Subtract -1.25D from result.
Describe Mohindra near retinoscopy
A near retinoscopy technique for assessment of distance refractive error. In completely dark room. Infant fixate at retinoscope at 50 cm. Subtract -1.25D from result.
How do you do ret on an infant?
Skioscopy bars. Use cyclopentolate.
