Eyes and
Vision
[Name of Presenter]
Doctor of Optometry
Presentation provided by:
Scott A. Jens, O.D.
AOA Member
Madison, WI
The Amazing Eye
The process of vision
 An object in the world is seen by the eye
upside down
 The brain processes the eye’s image to
create the picture of the object
ANDY
ANDY
Brain
ANDY
When vision is bad...
 The cornea and lens need to focus light
onto the retina for clear vision
 Often, the focus is not sharp...
Hyperopia (farsightedness)
Myopia (nearsightedness)
Astigmatism
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
25%
 Astigmatism
23%
 Myopia (nearsightedness)
18%
 Non-strabismic binocular disorders
14%
 Strabismus
12%
 Amblyopia
7%
 Accommodative disorders
6%
 Peripheral retinal abnormalities,
2%
requiring referral or follow-up
Hyperopia (farsightedness)
 Too little focusing power causes light to be
focused “behind” the retina
 Convex lenses focus light onto the retina
 A significant cause of learning problems, as it
often goes undetected by school or
pediatrician screenings
 Common cause of reading glasses
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
 Astigmatism
 Myopia (nearsightedness)
 Non-strabismic binocular disorders
 Strabismus
 Amblyopia
 Accommodative disorders
 Peripheral retinal abnormalities,
requiring referral or follow-up
25%
23%
18%
14%
12%
7%
6%
2%
Astigmatism
 The cornea/lens optical system is different in
the horizontal and vertical focal planes
 Found in combination with farsightedness
and nearsightedness
 Results in blur at distance and near
 Compound-grind lenses focus light onto the
retina
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
 Astigmatism
 Myopia (nearsightedness)
 Non-strabismic binocular disorders
 Strabismus
 Amblyopia
 Accommodative disorders
 Peripheral retinal abnormalities,
requiring referral or follow-up
25%
23%
18%
14%
12%
7%
6%
2%
Myopia (nearsightedness)
 Too much focusing power causes light to be
focused “in front” of the retina
 Concave lenses focus light onto the retina
 Early onset occurs between 2nd and 5th
grades, onset most common between grades
6th and 10th
 Many control methods examined, and none
work!
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
 Astigmatism
 Myopia (nearsightedness)
 Non-strabismic binocular disorders
 Strabismus
 Amblyopia
 Accommodative disorders
 Peripheral retinal abnormalities,
requiring referral or follow-up
25%
23%
18%
14%
12%
7%
6%
2%
Non-strabismic binocular
disorders
 The “binocular” system of humans depends
on vision from each eye that is equally clear
and overlapped into one image instead of
double
 Eye aiming can be miscoordinated
 Many learning difficulties can result from the
eyes not easily aiming at the same point -the more the effort, the more the fatigue, etc.
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
 Astigmatism
 Myopia (nearsightedness)
 Non-strabismic binocular disorders
 Strabismus
 Amblyopia
 Accommodative disorders
 Peripheral retinal abnormalities,
requiring referral or follow-up
25%
23%
18%
14%
12%
7%
6%
2%
Strabismus
 “Eye turn”
Crossed eye, esotropia
Wandering eye, exotropia
 Double vision is uncommon because of brain
adaptation called suppression
 Treatments include: proper prescription,
patch to equalize the individual eyes’ abilities,
and surgery by age 2 for greatest chance at a
functional cure
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
25%
 Astigmatism
23%
 Myopia (nearsightedness)
18%
 Non-strabismic binocular disorders
14%
 Strabismus
12%
 Amblyopia
7%
 Accommodative disorders
6%
 Peripheral retinal abnormalities,
2%
requiring referral or follow-up
Amblyopia
 Phrase “lazy eye” is often used to describe
amblyopia
 Permanent reduction of an eye’s best
sharpness, even with glasses, that results
from the brain constantly ignoring the image
of an eye that is crossed or from an eye that
is significantly different in prescription than
the other eye
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
25%
 Astigmatism
23%
 Myopia (nearsightedness)
18%
 Non-strabismic binocular disorders
14%
 Strabismus
12%
 Amblyopia
7%
 Accommodative disorders
6%
 Peripheral retinal abnormalities,
2%
requiring referral or follow-up
Accommodative disorders
 Accommodation = ability to “zoom” focus on
near objects
 Problems can include insufficient amount of
focus, overly active focus, lock of focus, and
slowly shifting focus
 The muscle that controls focus can be trained
to work more efficiently
 Bifocals can be used for children
Incidence of eye disorders,
age 6 mos. to 18 yrs.
 Hyperopia (farsightedness)
 Astigmatism
 Myopia (nearsightedness)
 Non-strabismic binocular disorders
 Strabismus
 Amblyopia
 Accommodative disorders
 Peripheral retinal abnormalities,
requiring referral or follow-up
25%
23%
18%
14%
12%
7%
6%
2%
Peripheral retinal
abnormalities
 Dilated eye examinations are periodically
required to evaluate parts of the inner eye
that can show abnormality
 Examples include retinal degenerations,
retinal detachments, and retinal tumors.
Inside the numbers...
 26% of US population is less than 18 years of
age
 31% of those 6 to 16 years old had an eye
and vision examination within the past year
 14% of those less than 6 years old had an
eye and vision examination within the past
year
Vision checkups and
screenings
 Many people benefit from having their eyes
tested with an eye chart to see if they see
properly -- called a “screening”
 Vision screening is never a replacement
for a comprehensive eye examination
 Screenings check for vision blurriness
 Exams evaluate vision blurriness,
PLUS eye muscle teaming, focus ability,
and eye health
Why so few eye exams?
 Parent reliance on vision screenings,
provided by pediatrician or school
 Cost to uninsured families
 Lack of good public information as to the
importance of periodic eye care
Unable to pay for
professional care?
NOTE: Due to differences in state,
province, and region free services, add
info applicable to audience, or remove
slide from presentation if services are
unavailable.
The Role of Vision in
Learning
 The eyes must see clearly, without double
vision, and with accurate depth of focus
control
 A child must have the visual ability to learn to
read prior to reading to learn
 When a child cannot learn, think first of their
ability to see, then of their ability to learn
Comprehensive Eye Exams
 Optometrists and ophthalmologists are eye
doctors who provide eye examinations
 Are easy and painless!
 Can find the problems that relate to poor
learning
 Here is a “peek”...
Color Vision
Depth Perception
Keratometry
Visual Acuity
Refraction
Eye Health Test
Eye Pressure
Eye Drops -- Dilating the
Pupil
Eye Health Tests
The “Headlight” Health
Exam
Tests for Babies and
Young Children, too!
Questions??
Thank you!!