1. Chapter 12
Eye

2. Objective 1: Identify organs and structures of the eye.
Chapter 12
Objective 1: Identify organs and structures of the eye.

3. The Eye
The eyes are organs of vision and are located in a bony protective cavity of the skull called the orbit. Only a small portion of the eye is visible from the exterior.

4. Eye sclera: outer protective layer of the eye (white of eye)
cornea: transparent anterior part of the sclera; allows the light rays to enter the eye
choroid: middle layer of the eye interlaced with blood vessels that supply nutrients to the eye
iris: the pigmented muscular structure that regulates the amount of light entering the eye by controlling the size of the pupil
pupil: opening in the center of the iris
Discuss these structures and their functions.
Iris was the special messenger of the Queen of Heaven according to Greek mythology. In this role she passed from heaven to earth over the rainbow while dressed in rainbow hues. Her name was applied to the circular eye muscle because of its varied colors.

5. Eye (cont’d)
lens: lies directly behind the pupil; focuses and bends light
retina: innermost layer of the eye, which contains the vision receptors
aqueous humor: watery liquid found in the anterior cavity of the eye; provides nourishment to nearby structures and maintains shape in the anterior part of the eye
vitreous humor: jellylike liquid found behind the lens in the posterior cavity of the eye that maintains its shape
Discuss these structures and their functions.

6. Eye (cont’d)
meibomian glands: oil glands found in the upper and lower edges of the eyelids that help lubricate the eye
lacrimal glands and ducts: produce and drain tears
optic nerve: carries visual impulses from the retina to the brain
conjunctiva: mucous membrane lining the eyelids and covering the anterior portion of the sclera
Discuss these structures and their functions.

7. Objective 2: Define and spell word parts related to the eye.
Chapter 12
Objective 2: Define and spell word parts related to the eye.

8. Combining Forms of the Eye
blephar/o
conjunctiv/o
cor/o, core/o, pupill/o
corne/o, kerat/o
dacry/o, lacrim/o
irid/o, ir/o
ocul/o, ophthalm/o
opt/o
phac/o, phak/o
retin/o
scler/o
Discuss how to build medical terms related to the eye from these combining forms.
Discuss how the combining forms cor/o and corne/o are similar but have different meanings.

9. Combining Forms Commonly Used with the Eye
cry/o
dipl/o
is/o
phot/o
ton/o
Discuss how to build medical terms related to the eye from these combining forms.

10. Prefixes and Suffixes Prefixes bi-, bin- Suffixes -opia -phobia
-plegia
Give examples of how these prefixes and suffixes are used to build medical terms related to the eye.
Prefixes
bi-, bin- = two
Suffixes
-opia = vision (condition)
-phobia = abnormal fear of or aversion to specific things
-plegia = paralysis

11. Spelling “ophthalm” Look closely at the spelling of “ophthalm.”
Medical terms containing “ophthalm” are often misspelled by omitting the first “h.” “ph” gives the “f” sound followed by the “th” sound of “thal.”
Think pronunciation when spelling terms that contain “ophthalm” as in “of[ph]-thal-MOL-o-jē”

12. Review Question Which is correct? opthalm/o ophthalm/o ophtham/o
Answer: b) ophthalm/o
Ask students to provide medical terms using the combining form ophthalm/o.

13. Chapter 12
Objective 8: Interpret, read, and comprehend medical language in simulated medical statements, documents, and electronic health records.

14. Read Medical Terms in Use
An elderly gentleman visited his ophthalmologist because of decreased vision. A tonometry examination showed borderline readings. Visual acuity measurement indicated a mild degree of myopia and presbyopia. A diagnosis of glaucoma was suspected in this case, and Timoptic eye drops were prescribed, one drop daily. A cataract of the right eye was found. Lens implant surgery will be performed when the cataract matures sufficiently. Approximately 5 years ago the patient had a detached retina of the left eye. A scleral buckling procedure was performed and was successful in halting the process of retinal detachment.
Ask students to define the bolded terms.