Certified Ophthalmic Assistant (COA) Exam – Practice Questions and Answers Study Guide
(Latest 2026 Update)
The study of the eye and it's surrounding structures, proper functions, eye diseases and
disorders, and all aspects of vision. - ✔✔Ophthalmology
a medical doctor specializing in the prevention, diagnosis, and medical as well as surgical
treatment of vision problems and eye diseases - ✔✔ophthalmologist
independent practitioner who completes a 4-year postgraduate, doctoral-level course in
optometry after typically obtaining a bachelor's degree. - ✔✔Optometrist
independent professional usually state licensed to make (dispense) eyeglasses and contact
lenses according to prescriptions supplied by an ophthalmologist or optometrist. - ✔✔Optician
specializes in testing visual function, particularly in infants and children, evaluating eye muscle
disorders, and evaluating impairments in binocular vision such as double vision. (bachelors + 2
years) - ✔✔Orthoptist
fabricates and fits patients with prostheses which replace a surgically removed eye or cover an
unsightly eye. - ✔✔Ocularist
photographs the eye structures for diagnosis and documentation. - ✔✔ophthalmic
photographer
any individual who help the ophthalmologist with diagnostic and treatment-oriented
procedures. - ✔✔ophthalmic medical assistant
- COA certified ophthalmic assistant
,- COT certified ophthalmic technician
- COMT certified ophthalmic medical technologist - ✔✔JCAHPO 3 levels of medical assistant
ophthalmologists who confine their practice to diagnosis and treating a defined area of the eye
or disease. - ✔✔subspecialist
clear, round membrane at the front of the globe. It focuses light the eye receives. - ✔✔Cornea
colored circle of tissue. controls the amount of light entering the eye by enlarging or reducing
the size of the opening in it's center. - ✔✔Iris
opening in the center of the eye - ✔✔pupil
(AKA - lens) second part of the optical focusing system of the eye. - ✔✔crystalline lens
(AKA - vitreous body) clear, jelly-like substance. This is optically transparent so as light focuses
through the vitreous it is unaffected by the substance. - ✔✔vitreous
light sensitive cells on the back of the eye that cover the image to electric impulses and send it
to the optic nerve. - ✔✔Retina
Carry the electric impulses made by the retina to the brain. - ✔✔Optic Nerve
range of front-to-back of the eye. Normal is between 23-25 millimeters in length. - ✔✔Axial
length
average is 545 micrometers (0.5 millimeters) - ✔✔central cornea thickness (CCT)
,an ultrasound test that measures the length of the corneal thickness - ✔✔pachymetry
60 diopters. cornea = 42 (40) diopters, lens = 18 (20) diopters - ✔✔refracting power of the eye
The tissues and structures surrounding the eye. They include the orbit, extra ocular muscles,
eyelids, and tear-producing and tear-draining lacrimal apparatus. They protect the globe. -
✔✔Adnexa
the pear-shaped bony cavity in the skull, compromising 7 bones that house the globe, extra
ocular muscles, blood vessels, and the nerves. - ✔✔Orbit
fracture in the floor of the orbit that results from blunt-force trauma - ✔✔Blowout fracture
control movement of the globe.
- medial rectus
- lateral rectus
- superior oblique
- inferior oblique
- superior rectus
- inferior rectus - ✔✔extraocular muscles
rotates the eye inward toward the nose, a movement called adduction. - ✔✔medial rectus
muscle
rotates the eye outward toward the temple, a movement called abduction - ✔✔lateral rectus
muscle
, primarily causes a torsional movement and twists the eye down and inward, a movement called
incyclotorsion - ✔✔superior oblique muscle
primarily causes a torsional movement and twists the eye up and outward, a movement called
excyclotorsion. - ✔✔inferior oblique muscle
primary muscle responsible for turning the eye upward, incyclotorsion - ✔✔superior rectus
muscle
primary muscle responsible for turning the eye downward, excyclotorsion - ✔✔inferior rectus
muscle
when the eyes are directed toward a single target and are perfectly aligned. - ✔✔binocular
vision
the brain blends the separate images received by the two eyes so that the person perceives a
single view. - ✔✔fusion
- ✔✔strabismus - when the extraocular muscles do not work in a coordinated manner, the
eyes become misaligned and vision may be disturbed.
the opening between the upper and lower lids - ✔✔palpebral fissure
the point where the eyelids meet on the nasal side of the palpebral fissure - ✔✔medial
canthus
the point where the eyelids meet on the temporal side of the palpebral fissure - ✔✔lateral
canthus
(Latest 2026 Update)
The study of the eye and it's surrounding structures, proper functions, eye diseases and
disorders, and all aspects of vision. - ✔✔Ophthalmology
a medical doctor specializing in the prevention, diagnosis, and medical as well as surgical
treatment of vision problems and eye diseases - ✔✔ophthalmologist
independent practitioner who completes a 4-year postgraduate, doctoral-level course in
optometry after typically obtaining a bachelor's degree. - ✔✔Optometrist
independent professional usually state licensed to make (dispense) eyeglasses and contact
lenses according to prescriptions supplied by an ophthalmologist or optometrist. - ✔✔Optician
specializes in testing visual function, particularly in infants and children, evaluating eye muscle
disorders, and evaluating impairments in binocular vision such as double vision. (bachelors + 2
years) - ✔✔Orthoptist
fabricates and fits patients with prostheses which replace a surgically removed eye or cover an
unsightly eye. - ✔✔Ocularist
photographs the eye structures for diagnosis and documentation. - ✔✔ophthalmic
photographer
any individual who help the ophthalmologist with diagnostic and treatment-oriented
procedures. - ✔✔ophthalmic medical assistant
- COA certified ophthalmic assistant
,- COT certified ophthalmic technician
- COMT certified ophthalmic medical technologist - ✔✔JCAHPO 3 levels of medical assistant
ophthalmologists who confine their practice to diagnosis and treating a defined area of the eye
or disease. - ✔✔subspecialist
clear, round membrane at the front of the globe. It focuses light the eye receives. - ✔✔Cornea
colored circle of tissue. controls the amount of light entering the eye by enlarging or reducing
the size of the opening in it's center. - ✔✔Iris
opening in the center of the eye - ✔✔pupil
(AKA - lens) second part of the optical focusing system of the eye. - ✔✔crystalline lens
(AKA - vitreous body) clear, jelly-like substance. This is optically transparent so as light focuses
through the vitreous it is unaffected by the substance. - ✔✔vitreous
light sensitive cells on the back of the eye that cover the image to electric impulses and send it
to the optic nerve. - ✔✔Retina
Carry the electric impulses made by the retina to the brain. - ✔✔Optic Nerve
range of front-to-back of the eye. Normal is between 23-25 millimeters in length. - ✔✔Axial
length
average is 545 micrometers (0.5 millimeters) - ✔✔central cornea thickness (CCT)
,an ultrasound test that measures the length of the corneal thickness - ✔✔pachymetry
60 diopters. cornea = 42 (40) diopters, lens = 18 (20) diopters - ✔✔refracting power of the eye
The tissues and structures surrounding the eye. They include the orbit, extra ocular muscles,
eyelids, and tear-producing and tear-draining lacrimal apparatus. They protect the globe. -
✔✔Adnexa
the pear-shaped bony cavity in the skull, compromising 7 bones that house the globe, extra
ocular muscles, blood vessels, and the nerves. - ✔✔Orbit
fracture in the floor of the orbit that results from blunt-force trauma - ✔✔Blowout fracture
control movement of the globe.
- medial rectus
- lateral rectus
- superior oblique
- inferior oblique
- superior rectus
- inferior rectus - ✔✔extraocular muscles
rotates the eye inward toward the nose, a movement called adduction. - ✔✔medial rectus
muscle
rotates the eye outward toward the temple, a movement called abduction - ✔✔lateral rectus
muscle
, primarily causes a torsional movement and twists the eye down and inward, a movement called
incyclotorsion - ✔✔superior oblique muscle
primarily causes a torsional movement and twists the eye up and outward, a movement called
excyclotorsion. - ✔✔inferior oblique muscle
primary muscle responsible for turning the eye upward, incyclotorsion - ✔✔superior rectus
muscle
primary muscle responsible for turning the eye downward, excyclotorsion - ✔✔inferior rectus
muscle
when the eyes are directed toward a single target and are perfectly aligned. - ✔✔binocular
vision
the brain blends the separate images received by the two eyes so that the person perceives a
single view. - ✔✔fusion
- ✔✔strabismus - when the extraocular muscles do not work in a coordinated manner, the
eyes become misaligned and vision may be disturbed.
the opening between the upper and lower lids - ✔✔palpebral fissure
the point where the eyelids meet on the nasal side of the palpebral fissure - ✔✔medial
canthus
the point where the eyelids meet on the temporal side of the palpebral fissure - ✔✔lateral
canthus
