1. CLINICAL PERSPECTIVES
STRUCTURES AROUND THE GLOBE
Orbit- provides a safe place for the eyeball
eyelids- closes light off of eye, protects, distributes tears
tears- lubricates & protects
lacrimal system- distributes tears
conjunctiva- covers sclera and inner surface of eyelids
orbital septum- bone covering top of orbit
eyebrow- covers orbital septum, protects eye from sweat

2. Photos courtesy of the National Eye Institute

3. Extraocular Muscles Superior & Inferior Recti Medial & Lateral Recti
Superior & Inferior Obliques

4. Eyelids & eyelashes
meibomian glands- oil glands

5. Conjunctiva sclera- white fibrous covering of eyeball
limbus- point where sclera and cornea meet

6. Lacrimal Apparatus puncta- inner margin of the upper & lower lids
caniliculi- passages to sacs & ducts
lacrimal sac- contains some tears
nasolacrimal duct- drains tears into nose

7. Eye Divided Into Two Parts
Anterior Segment
aqueous humor
pupil
Iris
lens
Posterior Segment
vitreous humor
retina
optic nerve

8. Cornea
clear, avascular window of the eye, most refractive power

9. Anterior Segment aqueous humor trabecular meshwork canal of Schlemm
ciliary process
lens

10. Pupil & Iris
Pupil- adjusts light
Iris- pigmented muscular ring

11. Structures In the Globe
3 Main Structures:
protective outer layer
vascular inner layer
sensory retina

12. Vascular Inner Layer
Uveal tract
Ciliary body
Choroid

13. Sensory Layer Central Retina Peripheral Retina
Macula & fovea contain mostly cones
Optic disk
Peripheral Retina
Contains mostly rods

14. Transmission of Visible Information to the Brain
Light energy from environment to chemical energy in retina to electrical energy in optic nerve & synapses to chemical energy in nerve cells

15. Relationship of Sight to Vision
Images from eye structures must be interpreted in the visual cortex for sight to occur

16. The eyes and associated structures must be normal in structure & function.
The neurological pathways from the retina & optic nerve to the visual cortex must be in tact.
The brain must be capable of interpreting the information received.

17. MEDICAL EYE REPORT Name Sex Age Family Medical Hx General Medical Hx
Surgical Hx
Medications
Ophthalmic complaint

18. Eye Care Professionals
Optometric technicians, ophthalmic technicians
Vision Rehabilitation practitioner
Teacher of Visually Impaired
D.O.- doctor of optometry, doctor of ophthalmology, low vision specialist
M.D.- ophthalmologist
Specialist- did fellowship in specialty, FACS
optician

19. VISUAL ACUITIES
Autorefractor
Lensometer
Snellen chart (distance)

20. Checking distance each eye using an occluder

21. Jaeger near vision chart

22. Ishihara- color vision charts

23. Titmus fly
Amsler grid

24. External Examination
LLL- Lids, lens, lacrimal system

25. CAUSES & FUNCTIONAL IMPLICATIONS OF VISUAL IMPAIRMENT

26. PERL- Pupils equal & reactive to light

27. MM- Muscular motility

28. Eye Muscle Balance

29. Cornea & Anterior Segment
Ophthane- numbs eye
Midriatic- dilates pupil
Cycloplegic- relaxes lens

30. Tonometer- measures pressure
FP- finger pressure
Air puff
Contact

31. Keratometer- measurement of corneal thickness

32. Goniometer- measures angle of anterior segment (risk factors for glaucoma)

33. Slit lamp

34. Direct ophthalmoscope

35. Undilated versus Dilated Pupil

36. Indirect ophthalmoscope

37. Normal Fundus

38. Phoropter

39. Functional & Visual Efficiency Testing
Behavioral
Electrophysiological
Subjective

40. Behavioral OKN (optokinetic nystagmus)- cortical
PLT (preferential looking test)- Teller acuities
Chromatic luminance- contrast sensitivity
Tracking a toy or light

41. Electrophysiological
Fundus photos & OCT
VER- visual evoked response- visual pathways, cortical function
ERG- electroretinogram (cone & rod function)
EOG- electrooculogram (measures charge & potentials of eyes)

42. Subjective Acuity CSF- contrast sensitivity function
Lea charts
Snellen
Tumbling E
Amsler grid
CSF- contrast sensitivity function
Flicker fusion macular & foveal function
Color- Ishihara & Farnsworth
Visual fields
Confrontation
Ganzfeld globe
computerized

43. Visual Efficiency Testing
ISAVE
Program to Improve Visual Efficency (Barraga)

44. Conditions That Result In Low Visual Acuity

45. Ocular Muscle Disorders-
eyes that are not in proper alignment

46. Strabismus & Amblyopia
amblyopia- a reduction in visual acuity due to non-use of the eye

47. tropia- marked deviation of an eye
esotropia- turning in of one or both eyes
exotropia- turning out of one or both eyes
hypertropia- turning up of one or both eyes
hypotropia- turning down of one or both eyes
phoria- tendency of eye to deviate, particularly when fatigued or fusion broken

48. Nystagmus
Involuntary, rhythmical repeated movement of one or both eyes in a horizontal, vertical or pendular motion
null point- point of least nystagmus & best vision
pendular nystagmus- up-and-down movements of equal speed, amplitude & duration
jerk nystagmus- slower movement in one direction