Cpoa/cpot Glossary

Front 1

absolute scotoma

Back 1

an area in which vision is entirely absent

Front 2

accommodation

Back 2

the ability of the eye to focus

Front 3

accommodative reserve

Back 3

the difference between supply and demand in the crystalline lens

Front 4

accounts payable

Back 4

money owed by the office

Front 5

accounts receivable

Back 5

money owed to the office

Front 6

acquired immune deficiency syndrome (AIDS)

Back 6

a syndrome of the human immune system caused by infection with human immunodeficiency virus (HIV)

Front 7

add power

Back 7

refers to the multifocal segments of a lens

Front 8

alcaine

Back 8

a synthetic topical anesthetic used on the cornea

Front 9

algerbrush

Back 9

a device to remove a rust ring from a corneal foreign body

Front 10

amblyopia

Back 10

reduced VA with no apparent cause and not correctable by refractive means

Front 11

ametropia

Back 11

the refractive condition that exists when accommodation is relaxed; parallel light rays entering the eye do not focus on the eye

Front 12

amplitude of accommodation

Back 12

ability of the crystalline lens in the eye to focus

Front 13

amsler grid

Back 13

a test to evaluate the integrity of central vision (macula)

Front 14

anacel

Back 14

used as a local anesthetic on the cornea

Front 15

angle of incidence

Back 15

the angle that is formed by the light ray and the surface of the medium

Front 16

angular magnification

Back 16

expressed as a ratio of the angle subtended by the image to that subtended by the object with respect to a viewing point of reference

Front 17

aniseikonia

Back 17

a difference in the size of the two retinal images

Front 18

anisometropia

Back 18

an unequal refractive status of the two eyes

Front 19

ankylosing spondylitis

Back 19

an arthritic disease linked to uveitis

Front 20

anomalous trichromat

Back 20

individual uses three colors but in different proportions
3 types:
protanomalous
deuteranomalous
tritanomalous

Front 21

protanomalous

Back 21

red weakness

Front 22

deuteranomalous

Back 22

green weakness

Front 23

tritanomalous

Back 23

blue-yellow weakness

Front 24

aphakia

Back 24

absence of the crystalline lens

Front 25

aqueous humor

Back 25

-clear fluid produced in the ciliary processes
-fills the space from the posterior cornea to the anterior vitreous
-maintains IOP
-nourishes the cornea, iris, and lens

Front 26

arcus senilis

Back 26

a ringshaped, grayish-white deposit of phospholipid and cholesterol near the peripheral edge of the cornea

Front 27

artificial tears

Back 27

topical eye-drops for use in the eye, formulated to relieve the symptoms of dry eyes

Front 28

a-scan

Back 28

instrument that uses sound waves to measure the eyeball length

Front 29

astigmatism

Back 29

optical defect in which the light entering the eye doesn't form a single point focus, but forms two focal points
5 types:
against-the-rule
irregular
lenticular
oblique
with-the-rule

Front 30

against-the-rule astigmatism

Back 30

steeper in the horizontal meridian

Front 31

with-the-rule astigmatism

Back 31

steeper in the vertical meridian (like a football lying on its side)

Front 32

irregular astigmatism

Back 32

principal meridians are not 90 degrees apart or when they are not uniformly positioned from point along a meridian

Front 33

lenticular astigmatism

Back 33

astigmatism of the crystalline lens

Front 34

oblique astigmatism

Back 34

meridians are between 30-60 degrees and 120-150 degrees

Front 35

axial length

Back 35

the length of the eyeball from the cornea to the posterior pole

Front 36

back vertex power (BVP)

Back 36

the vergence power expressed with reference to the posterior surface of a lens

Front 37

basal cell carcinoma

Back 37

common malignancy of the eyelids as a result of excessive exposure to sunight

Front 38

base curve

Back 38

reference surface of an ophthalmic lens classified by the manufacturer, maybe on the front or back surface

Front 39

base curve radius (BCR)

Back 39

back central region of the contact lens

Front 40

basic secretors

Back 40

glands whose rate of production is relatively constant

Front 41

benzalkonium chloride (BAK)

Back 41

a preservative used in topical eye drop preparations

Front 42

benzyl alcohol

Back 42

preservative used in GP lens solution

Front 43

beta blocker

Back 43

a drug whose topical effects lower IOP by decreasing aqueous production and whose systemic effects include slowing of the heart rate

Front 44

binocular

Back 44

simultaneous use of both eyes

Front 45

binocularity

Back 45

ability to maintain both eyes pointed at precisely the same object (teaming)

Front 46

bitoric lenses

Back 46

-a lens having toroidal surfaces on both sides
-used to correct astigmatism and aniseikonia

Front 47

blending

Back 47

a technique used to render edges of a bifocal almost invisible

Front 48

blepharitis

Back 48

inflammation of the lid margin

Front 49

blepharoconjunctivitis

Back 49

inflammation of the lid margin and adjacent conjunctiva

Front 50

blepharoplasty

Back 50

surgical eyelid procedure to correct for drooping eyelids and puffy bags below the eyes

Front 51

blepharoptosis (ptosis)

Back 51

abnormal drooping of an upper eyelid

Front 52

blepharospasm

Back 52

uncontrolled blinking in which the eyelids may become so tightly closed they cannot be opened

Front 53

blind spot

Back 53

area of the visual field occupied by the optic nerve head, which has no retinal receptors

a.k.a. absolute scotoma

Front 54

blink rate

Back 54

the amount a person blinks in a given unit of time

Front 55

blood pressure

Back 55

the force exerted against the arterial walls during the left ventricular contraction (heart beat) and relaxation (heart at rest)

Front 56

Bowman's membrane

Back 56

-second layer of the cornea
-tough membrane

Front 57

branch retinal artery occlusion

Back 57

only one side of the branches is blocked, resulting in partial loss of the field of vision

Front 58

brightness acuity tester (BAT)

Back 58

instrument to test for glare disability

Front 59

Bruch's membrane

Back 59

thin layer of connective tissue that is the most internal part of the choroid

Front 60

b-scan

Back 60

-instrument that uses sound waves to provide a cross section of the eye tissue
-used to evaluate structures that cannot be viewed directly

Front 61

bulbar conjunctiva

Back 61

transparent mucous membrane that covers the entire eye EXCEPT the cornea

Front 62

buphthalmos

Back 62

enlargement of the eye (seen in children with congenital glaucoma

Front 63

campimetry

Back 63

investigation of the integrity of the field of vision

Front 64

canal of Schlemm

Back 64

receives aqueous from the trabecular meshwork to be removed from the eye

Front 65

canaliculi

Back 65

small tubes located in the lacrimal sac

Front 66

canthi

Back 66

point where the upper and lower lids meet

Front 67

carbonic anhydrase inhibitors

Back 67

topical medication used to decrease aqueous production

Front 68

caruncle

Back 68

a pink fleshy mound at the medial canthus that contains sweat and oil glands, and sometimes hair

Front 69

cataract

Back 69

an opacity or cloudiness of the crystalline lens capsule
3 types:
cortical
nuclear
subcapsular

Front 70

cortical cataract

Back 70

appears within the cortex of the lens

Front 71

nuclear cataract

Back 71

positioned on the visual axis and may cause monocular diplopia

Front 72

subcapsular cataract

Back 72

appears at the posterior pole of the lens, causing glare effects in bright illumination

Front 73

cells and flare

Back 73

refers to white blood cells and protein floating in aqueous

Front 74

central corneal clouding (CCC)

Back 74

occurs when a contact lens in unable to supply enough oxygen to the central cornea

Front 75

central retinal artery

Back 75

main supplier of blood and oxygen to the retina

Front 76

central retinal artery occlusion (CRAO)

Back 76

blockage of the central retinal artery, which results in loss of oxygen in the retina, permanently destroying retinal cells (total loss of functional vision)

Front 77

central retinal vein occlusion (CRVO)

Back 77

generally caused by a thrombus (blood clot), which blocks or slows down the flow of blood, causing rapid reduction of vision

Front 78

chalazion (internal hordeolum)

Back 78

hard painless bump that results from a blocked meibomian gland of the eyelid

Front 79

chemosis

Back 79

edema of the conjunctiva

Front 80

chief complaint

Back 80

patient's reason for the office visit

Front 81

chlorhexidine

Back 81

a preservative used in RGP solutions

Front 82

choroid

Back 82

network of blood vessels that provide vascular support to the structures around it

Front 83

choriocapillaris

Back 83

choroid layer that lies next to the retina and is made up of capillaries

Front 84

ciliary body

Back 84

-located immediately behind the iris and just inside the sclera
-major functions are production of aqueous humor and accommodation

Front 85

ciliary muscle

Back 85

smooth muscle of the ciliary body that is responsible for the change in focus when looking from far to near

Front 86

computerized axial tomography (CAT) scan

Back 86

an x-ray technique used to visualize internal structures

Front 87

concave lens

Back 87

-a lens that is thinner in the center and thinker at the edges
-parallel light passing through this type of lens is diverged, refracted away from the midlne
-a.k.a. minus lens

Front 88

cones

Back 88

photoreceptors responsible for color discrimination

Front 89

confrontation fields

Back 89

a technique used to screen for visual field defects using the fingers of the examiner

Front 90

congruous

Back 90

identical defects in the visual field

Front 91

conjunctiva

Back 91

a mucous membrane that covers the inside of the eyelids and the outside of the globe

Front 92

marginal conjunctiva

Back 92

the part beginning at the gray line and covers the entire surface of the inside of the lids

Front 93

orbital conjunctiva

Back 93

the part of the conjunctiva above or below the tarsal plates

Front 94

palpebral conjunctiva

Back 94

the marginal, tarsal, and orbital portions which line the inside of the eyelids

Front 95

tarsal conjunctiva

Back 95

the part of the conjunctiva lining the inside of the lid and covering the upper and lower tarsal plates

Front 96

conjunctivitis

Back 96

inflammation of the conjunctiva

Front 97

contrast sensitivity test

Back 97

a test that measures the patient's perception of the difference between the compared stimuli

Front 98

convergence

Back 98

simultaneous turning in of both eyes that occurs when viewing an approaching object

Front 99

convex lens

Back 99

-a lens that is thicker in the center and thinner at the edges
-parallel light rays passing through this type of lens are refracted by each surface to converge toward the midline behind the lens
-a.k.a. plus lens

Front 100

cornea

Back 100

transparent, front part of the eye that covers the anterior chamber, and is the major refracting surface of the eye

Front 101

corneal abrasion

Back 101

a scraping away of part of the surface of the cornea

Front 102

corneal neovascularization

Back 102

new vessels growing into the cornea, disturbing the transparency

Front 103

corneal sensitivity

Back 103

testing the sensitivity of the cornea to external stimuli

Front 104

corneal topography

Back 104

method of analyzing the curves of the cornea

Front 105

corneal transplant/Penetrating Keratoplasty (PKP)

Back 105

replacement of a scarred cornea with a donor cornea

Front 106

CR-39

Back 106

material used to make standard ophthalmic plastic lenses

Front 107

crowding phenomenon

Back 107

the increased difficulty in identifying targets that are closely adjacent to other targets

Front 108

crown glass

Back 108

ophthalmic quality of glass used to make lenses

Front 109

crystalline lens

Back 109

a structure that changes shape to accommodate from near to far, second most powerful refracting component of the eye

Front 110

cycloplegic

Back 110

a parasympatholytic pharmocologic agent that paralyzes the ciliary body, causing loss of accommodation and, by sphincter paralysis, dilation

Front 111

cytomegalovirus (CMV)

Back 111

an infection of the retina

Front 112

dacrocyctitis

Back 112

an inflammation and/or infection of the lacrimal sac

Front 113

dacrocystorhinostomy

Back 113

surgery that creates a bypass channel from the nasolacrimal system into the nose

Front 114

decongestants

Back 114

pharmaceuticals that cause vasoconstriction and subsequent nasal relief

Front 115

dermatochalasis

Back 115

excessive eyelid skin caused by loss of elastic tissue

Front 116

Descemet's membrane

Back 116

fourth layer of the cornea; very thin, maintains integrity of corneal endothelium

Front 117

diabetes mellitus

Back 117

metabolic disease in which the body doesn't produce or properly use insulin

Front 118

diabetic retinopathy

Back 118

retinal damage occurring to patients with diabetes

Front 119

dilator muscle

Back 119

responsible for the opening of the pupil

Front 120

diastolic pressure

Back 120

-2nd and lowest number of a blood pressure reading
-reflects the amount of force when the heart is at rest

Front 121

diopter

Back 121

unit of refractive power (D)

Front 122

diplopia

Back 122

double vision

Front 123

direct ophthalmoscope

Back 123

used to examine the optic disc and central retina

Front 124

disinfection

Back 124

to destroy harmful bacteria and viruses

Front 125

divergence

Back 125

ability of both eye to move laterally simultaneously

Front 126

ductions

Back 126

monocular eye movements

Front 127

dynamic stabilization

Back 127

-alteration of the edge design of a lens
-thin zones are at the top and bottom and covered by the lids, thicker center positions horizontally between the lids

Front 128

eccentric fixation

Back 128

retinal area fixation other than the fovea

Front 129

eccentric lenticulation

Back 129

front surface, off-center lenticular cut in the direction of the prism apex

Front 130

ectropion

Back 130

abnormal outward turning of an eyelid

Front 131

edema

Back 131

swelling of tissues due to fluid influx

Front 132

eikonometer

Back 132

instrument that measures aniseikonia

Front 133

electronic magnification

Back 133

a combination of relative size and relative distance magnification accomplished through the use of electronic equipment

Front 134

electronic medical record (EMR)

Back 134

records in offices that enter all patient medical information into a computer database

Front 135

emergency

Back 135

a sudden, generally unexpected occurrence or set of circumstances demanding immediate attention

Front 136

emmetropia

Back 136

the power of the cornea and the lens at rest correspond with the axial so, parallel light rays are appropriately refracted to focus on the retina

Front 137

endothelium

Back 137

deepest layer of the cornea, single thickness layer of cells

Front 138

entropion

Back 138

abnormal inward turning of an eyelid

Front 139

Epi-LASIK

Back 139

uses a slightly different microkeratome which removes only the epithelium, the rest of the procedure is similar to LASEK

Front 140

epiphora

Back 140

an excessive amount of tearing (reflex tearing)

Front 141

episclera

Back 141

layer of connective tissue lying between the sclera and the bulbar conjunctiva supplying most of the nutrients to the sclera

Front 142

episcleritis

Back 142

inflammation of the episclera

Front 143

epithelium

Back 143

top layer of the cornea

Front 144

-eso

Back 144

in

Front 145

ethylenediaminetetracetic acid (EDTA)

Back 145

eyedrop preservative

Front 146

excimer laser

Back 146

produces high-energy laser light which causes an almost instantaneous vaporization of small amounts of the cornea by direct photochemical disruption of molecular bonds, with minimal impact on neighboring ocular areas

Front 147

-exo

Back 147

out

Front 148

exophthalmometer

Back 148

instrument used to measure and monitor exophthalmos and lid retraction

Front 149

exophthalmos

Back 149

a protrusion or forward bulging of the eye with retraction of the eyelid

Front 150

extraocular muscles

Back 150

six muscles which are attached to the globe and coordinate eye movements

Front 151

exudates

Back 151

fluid, fat, and protein leaking from faulty blood vessels

Front 152

eye teaming

Back 152

ability to maintain both eyes pointed at precisely the same object (binocularity)

Front 153

facility

Back 153

the ability to be able to change the focusing system accurately and sustain focusing for long periods of time

Front 154

Fairness to Contact Lens Consumers Act (FCLCA)

Back 154

legislation that requires practitioners provide their contact lens patient with a copy of their RX on completion of the fitting process

Front 155

femtosecond laser

Back 155

used in creating the flap by placing tiny bursts of energy at a prescribed depth in the stroma during LASIK

Front 156

first-degree fusion

Back 156

superimposition

Front 157

flashes

Back 157

caused by the physical stimulation of the retina or loose portions of a retinal flap within the vitreous

Front 158

flat fusion

Back 158

two similar objects are seen as a single object (second-degree fusion)

Front 159

floaters

Back 159

dark or translucent floating specks in the vitreous that cast a shadow on the retina

Front 160

fluorescein

Back 160

a dye used topically to evaluate corneal integrity and intravenously to evaluate blood vessels integrity

Front 161

fluorescein angiography

Back 161

a specialized technique for observing the retina, in which rapid serial photography records retinal circulation following the intravenous injection of fluorescein

Front 162

fluoro-silicone acrylate (F-S/A_

Back 162

material used in second generation GP lenses, with the addition of fluorine

Front 163

focal length

Back 163

the distance from the lens to the point where the light rays meet on the midline

Front 164

follicles

Back 164

holes in the eyelid skin through which hairs (eyelashes) protrude

Front 165

foramens

Back 165

opening which allow arteries, veins, and nerves to enter and leave the orbit

Front 166

fornix

Back 166

junction between the bulbar and palpebral conjunctiva

Front 167

fovea centralis

Back 167

-central 1.5 mm area of the macula
-responsible for the sharpest vision, fine discriminations, and high VA
-area of the highest concentration of cone cells and no blood vessels

Front 168

front surface toric lenses

Back 168

a lens with toricity on the front surface

Front 169

fundus

Back 169

interior portion of the eyeball that can be seen on ophthalmoscopy or photography; includes the retina and optic disc

Front 170

fundus photography

Back 170

color photos taken of the posterior portion of the patient's eye

Front 171

fusion

Back 171

the merging of the images from each eye into a single visual image

Front 172

Galilean telescope

Back 172

a refracting telescope that produces an erect, virtual image

Front 173

gas permeable (GP)

Back 173

contact lens materials that maximize oxygen permeability and transmission

Front 174

glands of Krause

Back 174

accessory glands that produce the watery layer to the tear film in conjunction with the lacrimal gland

Front 175

glands of Moll

Back 175

sweat glands located in the lid margin

Front 176

glands of Wolfring

Back 176

accessory glands that produce the watery layer to the tear film in conjunction with the lacrimal gland

Front 177

glands of Zeis

Back 177

sebaceous glands attached to the follicles of the eyelashes, producing oil that protects the lashes from drying out and becoming brittle

Front 178

glare test

Back 178

a test for glare induced by cataract

Front 179

glaucoma

Back 179

elevated IOP
6 types:
low tension
acute angle closure
congenital
low/normal tension
primary open angle
secondary

Front 180

low/normal tension glaucoma

Back 180

IOP within normal range, but either or both the optic nerve and visual field are damaged

Front 181

acute angle closure glaucoma

Back 181

anterior chamber angle becomes blocked, stopping aqueous outflow, resulting in a rapid increase in IOP

Front 182

congenital glaucoma

Back 182

high IOP in one or both eyes from birth

Front 183

primary open angle glaucoma (POAG)

Back 183

steady inflow/outflow of aqueous is no longer maintained, resulting in increased IOP

Front 184

secondary glaucoma

Back 184

results from a separated ocular manifestation or injury which decrease outflow of aqueous

Front 185

glaucoma surgery

Back 185

procedures performed to reduce IOP
7 types:
aqueous shunt
cyclocryotherapy
iridectomy
trabeculotomy
selective trabeculoplasty
trabeculoplasty
iridotomy

Front 186

aqueous shunt

Back 186

insertion of a tiny plastic tube from the anterior chamber to reservoir that is placed halfway back around the eye for treating glaucoma

Front 187

cyclocryotherapy

Back 187

a freezing probe is placed to half the ciliary body, destroying a portion of the fluid making ability of the eye for treating glaucoma

Front 188

iridectomy

Back 188

a small piece of the iris is removed, allowing an alternate route for aqueous flow

Front 189

trabeculotomy

Back 189

surgical procedure for glaucoma that creates a bypass drain which is located in the sclera under the upper lid

Front 190

selective trabeculoplasty (SLT)

Back 190

uses a laser that produces less energy than the one used for trabeculopasty and can be repeated up to 4 time

Front 191

trabeculoplasty

Back 191

procedure used for POAG; microscopic burns are made in the trabecular meshwork

Front 192

iridotomy

Back 192

laser beam makes a small hole in the iris allowing an alternate route for aqueous flow

Front 193

Grave's disease

Back 193

associated with hyperthyroidism

Front 194

gray line

Back 194

junction of the skin and conjunctiva which is gray in color

Front 195

Haller's layer

Back 195

outermost layer of the choroid, made up of large vessels

Front 196

Health Insurance Portability and Accountability Act (HIPAA)

Back 196

regulations developed to protect patient's health information

Front 197

hemianopsia/hemianopia

Back 197

a defect affecting about half the visual field

Front 198

hepatitis B

Back 198

inflammation of the liver caused by the hepatitis B virus

Front 199

herpes zoster ophthalmicus (shingles)

Back 199

caused by the varicella virus; forehead, eyelids, and conjunctiva are involved

Front 200

high-index plastic

Back 200

made of polyurethane, and due to its properties, these lenses are the thinnest

Front 201

histoplasmosis capulatum

Back 201

fungal infection thought to be responsible for ocular histoplasmosis syndrome

Front 202

Hofstetter's formula

Back 202

A=18.5-0.15Y

where A is the average amplitude of accommodation and Y is age

Front 203

homonymous

Back 203

a defect exists in both eyes and affects the same field in both eyes

Front 204

hydrogen peroxide

Back 204

chemical disinfectant used for contact lens disinfection

Front 205

hydrophilic

Back 205

related to having a strong attraction to water

Front 206

hyper

Back 206

up

Front 207

hyperopia

Back 207

a refractive condition in which, when accommodation is relaxed, parallel light rays entering the eye focus behind the retina

a.k.a. farsighted

Front 208

hyperosmotic

Back 208

a solution with a greater osmotic gradient than surrounding tissues

Front 209

hypertension

Back 209

elevated blood pressure

Front 210

hyphema

Back 210

pooling of blood in the anterior chamber

Front 211

hypo

Back 211

down/under

Front 212

ICD-9-CM Diagnosis Codes for Optometry

Back 212

codes used for billing

Front 213

index of refraction

Back 213

a number that indicates the speed of light through a medium compared with the speed of light in a vacuum (n)

Front 214

inferior

Back 214

one of the four principle anatomic directions; towards the feet

Front 215

interpupillary distance (PD)

Back 215

distance between the centers of the pupil of each eye

Front 216

intraocular lens implant (IOL)

Back 216

a replacement lens surgically inserted i the same area from which a patient's crystalline lens was removed

Front 217

intraocular pressure (IOP)

Back 217

fluid pressure maintained in the eye by the aqueous humor; measure with a tonometer

Front 218

intraocular silicone oil

Back 218

tamponade injection of silicone oil into the vitreous to treat retinal detachment

Front 219

iridocyclitis

Back 219

occurs during uveitis when the swollen iris adheres to peripheral cornea (anterior synechia)

Front 220

iris

Back 220

colored part of the eye

Front 221

isopter

Back 221

a contour line in visual fields representing connecting points of retinal sensitivity

Front 222

Kaposi's sarcoma

Back 222

malignant growth on the eyelids and conjunctiva

Front 223

Keplerian telescope

Back 223

an astronomic telescope

Front 224

keratitis

Back 224

inflammation of the cornea

Front 225

keratitis sicca

Back 225

corneal inflammation resulting from deficient tear production

Front 226

keratoconjunctivitis

Back 226

inflammation of the cornea and conjunctiva

Front 227

keratoconus

Back 227

degenerative corneal disease characterized by thinning and cone-shaped protrusion of the cornea

Front 228

keratometer/ophthalmometer

Back 228

an instrument used to measure the curvature of the central 3.3 mm cornea in each of its two meridians

Front 229

keratometry

Back 229

measurement of the corneal curvature; measured with a keratometer

Front 230

kinetic perimetry

Back 230

target is in motion during visual field testing

Front 231

k-readings

Back 231

measurement obtained from the keratometer used to determine astigmatism and for contact lens fitting

Front 232

lacrimal fossa

Back 232

two depressions in the orbit

Front 233

lacrimal sac

Back 233

located in the first "lacrimal fossa", located nasally where tear fluid is collected

Front 234

lacrimal system

Back 234

responsible for the production, maintenance, and elimination of tear film

Front 235

lacrimation

Back 235

tearing of the eye

Front 236

lagophthalmos

Back 236

eyelid retraction or downward gaze, ocular symptom of exophthalmos

Front 237

LASIK

Back 237

-Laser Assisted In Situ Keratomileusis
-refractive surgery procedure that uses the excimer laswer and a specially designed knife blade called a microkeratome

Front 238

LASEK

Back 238

-Laser Epithelial Keratomileusis
-removes surface epithelium with a trephine, which is then folded back and the excimer laser is used to remove the corneal tissue; the epithelial flap is placed back over the eye and a temporary bandage contact lens is used to keep the flap in place

Front 239

lateral

Back 239

one of the four principle anatomical directions, away from the midline

Front 240

lateral canthus

Back 240

angle created where the upper and lower lids are joined close to the ear

Front 241

lateral geniculate nucleus (LGN)

Back 241

area where synapse occurs between the terminal ends of the ganglion cell axons and the dendrites of the nerve fibers, which carry visual information to the visual cortex

Front 242

left optic tract

Back 242

combination of fiber bundles from the two optic nerves continues from the left side of the ciasm (represents the right visual field)

Front 243

legal blindness

Back 243

patient with 20/200 or worse in the better eye, or with less than 20 degrees of visual field in the better eye

Front 244

lens clock

Back 244

instrument used to measure the surface powers of a lens

Front 245

cylindrical lenses

Back 245

power in only one meridian

Front 246

spherocylindrical lenses

Back 246

has a different power in each of its principle meridians

Front 247

aphakic lenses

Back 247

lenses fitted on a patient who has had a cataract surgery but didn't have an IOL implanted during surgery

Front 248

blanace lenses

Back 248

a lens ordered for a monocular patient to balance the eye wear cosmetically

Front 249

bifocal lenses

Back 249

a lens that provides both distance and near correction

Front 250

fresnel press-on lenses

Back 250

a thin plastic sheet that is placed on the ocular surface of an existing lens; available in prism, plus, and minus powers, and a precut plus power bifocal power

Front 251

lenticular lenses

Back 251

a design used on lenses to reduce thickness and weight

Front 252

myodisc lenses

Back 252

high minus lenses with a lenticular design

Front 253

planocylindrical lenses

Back 253

has no power in one meridian and the meridian 90 degrees away has the most power

Front 254

progressive addition lenses

Back 254

have distance power in the upper portion of the lens, with the power progressively changing to the near prescription in the lower portion of the lens

Front 255

spherical lenses

Back 255

has the same power in all meridians

Front 256

spherocylindrical lenses

Back 256

has spherical components throughout the lens, and is the exclusive power in the axis meridian' the cylindrical power varies in all meridian, with the maximum cylindrical power being 90 degrees from the axis meridian

Front 257

trifocal lenses

Back 257

lenses that correct for distance, intermediate, and near vision

Front 258

lensometer/lensmeter

Back 258

an instrument used to measure the power of a lens

Front 259

leukocytes

Back 259

white blood cells floating in the aqueous

Front 260

levator palpebrae superioris

Back 260

eyelid muscle that is responsible for eyelid retraction (opening)

Front 261

limbus

Back 261

-the area of the eye dividing the cornea from the sclera
-the junction, marked by a furrow, where the sclera and cornea meet

Front 262

macula lutea

Back 262

central portion of the retina surrounding the fovea; responsible for acute central vision

Front 263

macular degeneration

Back 263

a disease of the eye involving loss of structure and function of the macula; also called age-related (AMD) and senile
2 types:
dry
wet

Front 264

dry macular degeneration

Back 264

most common form, develops slowly as the submacular tissue gradually deteriorates

Front 265

wet macular degeneration

Back 265

formation of abnormal blood vessels that have a tendency to leak fluid or bleed (more severe)

Front 266

macular sparing

Back 266

term given to a visual field where a complete hemianopsia exists, except for the central 2-5 degrees, where it is intact

Front 267

magnetic resonance imaging scan

Back 267

a noninvasive diagnostic technique that produces computerized images of the internal structures of the body

Front 268

magnification

Back 268

an increase in apparent size of an image or object

Front 269

malingering

Back 269

feigning or deliberately giving false test responses, indicating illness or disability for personal gain

Front 270

medial

Back 270

one of the four principle anatomical directions; toward the midline - the nose is on the midline

Front 271

medial canthus (nasal)

Back 271

angle created where the upper and lower lids are joined near the nose

Front 272

meibomian glands (tarsal)

Back 272

glands with openings in the upper and lid margins which produce the oil that floats on the watery layer of the tear film

Front 273

melanocytes

Back 273

pigment cells

Front 274

metamorphopsia

Back 274

distortion of vision

Front 275

microaneurysms

Back 275

retinal blood vessels that have enlargened and developed weak spots

Front 276

microkeratome

Back 276

an instrument that cuts a thin flap in the cornea during the LASIK procedure

Front 277

microscope

Back 277

a magnifying optical instrument

Front 278

minus lens

Back 278

a lens that diverges light

Front 279

miotic drugs

Back 279

stimulate the sphincter muscle of the iris, causing constriction of the pupil

Front 280

monochromat

Back 280

individual who sees everything in the same color

Front 281

monocular

Back 281

use of only one eye

Front 282

monovision

Back 282

technique that sets one eye for distance vision (normally the dominant eye) and one eye for near vision

Front 283

motor fusion

Back 283

eye movement that occurs to keep eyes aligned on the target

Front 284

Mueller's muscle

Back 284

one of the muscle's involved in the retraction of the eyelid

Front 285

multifocals

Back 285

lenses designed to meet visual rquirements for different circumstances

Front 286

Myasthenia Gravis

Back 286

a systemic acquired autoimmune disorder resulting in abnormal fatigue and exhaustion of striated muscles

Front 287

mydriatic drugs

Back 287

stimulate the dilator muscle to make the pupil larger

Front 288

myopia

Back 288

a refractive condition in which, when accommodation is relaxed, parallel light rays entering the eye focus in front of the retina; also called nearsighted

Front 289

nasolacrimal duct

Back 289

larger tube leading to the nasal cavity

Front 290

neurologist

Back 290

a physician who specializes i the study of the nerves

Front 291

non-pigmented epithelium

Back 291

central layer of the iris

Front 292

non-proliferative (background)

Back 292

subtle changes found in a diabetic eye

Front 293

occlusion amblyopia

Back 293

reduced, uncorrectable VA caused by inadequate sensory information as a result of congenital ptosis

Front 294

ocular adnexa

Back 294

structures surrounding the eye

Front 295

ocular toxoplasmosis

Back 295

protozoan causing inflammation of the retina and choroid resulting in a dense pigmented-surrounded scar when healed

Front 296

oculoplasty surgery

Back 296

involves the treatment of eye disorders

Front 297

ophthalmoscope - indirect

Back 297

an instrument uses to take stereoscopic views of the fundus

Front 298

ophthetic/ophthaine

Back 298

a synthetic topical anesthetic used on the cornea

Front 299

ophthalmoscopy

Back 299

examination of the interior of the eye with an ophthalmoscope

Front 300

optic chiasm

Back 300

formed by the fusion of the optic nerves near the pituitary gland; at this point the nasal retinal fibers cross to join the temporal fibers of the other eye

Front 301

optic radiations

Back 301

axons of the cells in the LGN that continue to the visual cortex

Front 302

optical cross

Back 302

a diagram that denotes the dioptic power in the two principle meridians of a lens

Front 303

optical infinity

Back 303

the distance where light rays become parallel - 20 ft or 6 m

Front 304

optical zone diameter (OAZ)

Back 304

central area of the contact lens that corrects the patient's vision

Front 305

ora serrata

Back 305

marks the end of the choroid; one of the areas where the retina is attached to the choroid

Front 306

orbicularis oculi

Back 306

eyelid muscle that is responsible for eyelid closure

Front 307

orbit

Back 307

the bony socket that contains the eye and most of its accessory muscles, glands, nerves, and blood vessels

Front 308

ortho

Back 308

referring to the eyes being in perfect, or straight ahead, alignment

Front 309

orthokeratology

Back 309

a treatment for myopia that uses a series of progressively flatter contact lenses to flatten the cornea

Front 310

orthoptics

Back 310

another term used for vision therapy

Front 311

over-refraction

Back 311

refraction of a patient wearing a contact lens

Front 312

oxygen permeability (Dk)

Back 312

the ability for oxygen to penetrate a contact lens

Front 313

pachymeter

Back 313

instrument that determines the thickness of the cornea

Front 314

pachymetry

Back 314

measuring the thickness of the cornea

Front 315

palpebrae (eyelids)

Back 315

reinforced folds of skin that protect the eyes and orbits

Front 316

palpebral aperture/fissure

Back 316

the space between the eyelid margins

Front 317

palpebral conjunctiva

Back 317

lines the inner lids, meeting the bulbar conjunctiva at the fornix

Front 318

pan-retinal photocoagulation

Back 318

laser burns in the peripheral retina to reduce swelling and risk of bleeding

Front 319

pantoscopic tilt

Back 319

the angle that the frame front makes with the temples when viewed from the side

Front 320

papilla

Back 320

a small, nipple-shaped elevation

Front 321

periballasting

Back 321

limiting the prism ballast to the contact lens periphery only; it's excluded from the optical zone

Front 322

perimetry

Back 322

the study of the visual fields

Front 323

peripheral bevel

Back 323

the width of the outside or peripheral curve of a contact lens

Front 324

peripheral vision

Back 324

the visual fields representing side vision

Front 325

permeability

Back 325

the ability of the contact lens material to allow oxygen to pass through it, commonly referred to as 'Dk'

Front 326

phacoemulsification

Back 326

uses an ultrasonic instrument to break up the cataract into tiny fragments that can be suctioned out of the capsular bag

Front 327

phoria

Back 327

tendency of an eye or eyes to deviate from the ortho

Front 328

phoropter

Back 328

trademark of one specific manufacturer or refractors

Front 329

photophobia

Back 329

symptom causing pain on viewing a light; light sensitive

Front 330

photopic

Back 330

pertaining to daylight vision

Front 331

photopigments

Back 331

chemicals used to collect the light energy in the photoreceptors

Front 332

photoreceptors

Back 332

retinal elements that convert light to electrical impulses

Front 333

photorefractive keratectomy (PRK)

Back 333

an excimer laser is used to reshape the cornea

Front 334

physiologic blind spot

Back 334

the area of scotoma associated with the optic nerve head

Front 335

pigmented epithelium

Back 335

deepest layer of the iris

Front 336

pilocarpine

Back 336

most commonly used miotic drug

Front 337

pinguecula

Back 337

a yellowish-white, slightly raised mass found in the nasal and temporal conjunctiva, resulting from excessive sun exposure

Front 338

plica semiluminaris

Back 338

a crescent-shaped conjunctival fold at the medial canthus, lateral to the caruncle

Front 339

plus lens

Back 339

a lens that converges light

Front 340

pneumatic retinopexy

Back 340

intraocular injection of an inert gas into the vitreous used to treat retinal detachment

Front 341

polyaminopropyl biguanide (PAPB)

Back 341

preservative used in GP lens solution

Front 342

polycarbonate

Back 342

a form of plastic which is highly impact-resistant, used to make ophthalmic lenses

Front 343

polymethylmethacrylate (PMMA)

Back 343

a clear plastic material used for RGP; first material used after glass

Front 344

polyquad

Back 344

preservative used in GP lens solutions

Front 345

pontocaine

Back 345

used as a local anesthetic on the cornea

Front 346

posterior capsule opacity (secondary cataract)

Back 346

haze of opacity that develops in the membrane (posterior capsule), behind the intraocular lens implant

Front 347

posterior vitreous detachment (PVD)

Back 347

the detachment of the vitreous from its attachment on the retina and producing symptoms of a floater (normally age-related)

Front 348

potential acuity meter (PAM)

Back 348

used to determine the patient's potential visual acuity after cataract surgery

Front 349

presbyopia

Back 349

the condition in which lost elasticity of the lens leads to the inability to accommodate

Front 350

pressure patch

Back 350

placement of a patch over the eye in some cases of corneal abrasion

Front 351

presumed ocular histoplasmosis syndrome (POHS)

Back 351

an infection that causes decreased or distorted central vision, frequently diagnosed in patients with an exposure to pigeons or chickens

Front 352

principle meridians

Back 352

meridians with the greatest and least power and are 90 degrees apart

Front 353

prism

Back 353

a lens that bends light

Front 354

prism ballast

Back 354

incorporation of prism into a lens to maintain rotational stability

Front 355

proliferative retinopathy

Back 355

appearance of new, abnormal blood vessels that grow (proliferate) over the retina and optic nerve

Front 356

proparacaine hydrochloride

Back 356

generic name for ophthaine, alcaine, and ophthetic

Front 357

prostaglandin analogs

Back 357

topical medication used to increase aqueous outflow

Front 358

pseudoaphakia

Back 358

term used for the aphakic correction after a lens implant

Front 359

pterygium

Back 359

a raised, whitish, triangle-shaped wedge of fibrovascular tissue, which can extend across the cornea

Front 360

puncta

Back 360

small holes in the upper and lower lid margin (tear drain) near the nasal canthus

Front 361

pupillary frill

Back 361

part of the pigmented epithelium that extends around the edge of the pupil

Front 362

pursuits

Back 362

eye movements as the follow a moving target: smooth eye movements

Front 363

quadrantanopsia/quadrantanopia

Back 363

a defect affecting about a quarter of the visual field

Front 364

Radial Keratotomy (RK)

Back 364

refractive error corrected by surgically creating a series of cuts into the cornea to flatten the center

Front 365

radiuscope

Back 365

an instrument that measures the curvature of a contact lens

Front 366

recession

Back 366

eye muscle is cut from its original attachment and is reattached further back on the eye

Front 367

reflex blinking

Back 367

rapid forceful closure of the eyelids to protect the eyes

Front 368

refraction

Back 368

altering of the pathway of light as it passes from one medium to another

Front 369

refractor

Back 369

instrument used to determine subjective refraction

Front 370

relative distance magnification

Back 370

an apparent change in an object size based on moving the object close to the observer

Front 371

relative size magnification

Back 371

physically enlarging an object when seen at the same viewing distance

Front 372

residual astigmatism

Back 372

difference between corneal toricity and refractive astigmatism

Front 373

reticle

Back 373

a hand-held magnifier used to verify the overall contact lens diameter

Front 374

retina

Back 374

the light sensitive tissue lining the back of the eye, containing sensory receptors (rods & cones)

Front 375

pneumatic retinopathy

Back 375

retinal repair with either a laser or cryotherapy and then placement of a gas bubble inside the vitreous cavity

Front 376

scleral buckle

Back 376

silicone band sutured onto the sclera to apply pressure over the retina to treat for a detachment

Front 377

retinal detachment/tear

Back 377

occurs when the sensory retinal tissue separates from the underlying pigment epithelium

Front 378

retinal hole

Back 378

a hole which allows fluid from the vitreous to pass into the subretinal area

Front 379

retinitis pigmentosa

Back 379

bilateral, hereditary, progressive degeneration of the retina, mainly the rods, leaving the patient with "tunnel vision"

Front 380

retinoscope

Back 380

an instrument used to perform an objective refraction

Front 381

retinoscopy

Back 381

determining the refractive state of an eye objectively

Front 382

right optic tract

Back 382

combination of fiber bundles from the two optic nerves continues from the right side of the ciasm (represents the left visual field)

Front 383

rods

Back 383

photoreceptors whose function is based on the presence or absence of light energy (used for peripheral and night vision)

Front 384

saccades

Back 384

eye movements when looking from one target to another; jumping, two-eyed movements

Front 385

Sattler's layer

Back 385

next distinct layer of the choroid, made up of vessels that are considered to be medium-sized

Front 386

Schirmer test

Back 386

filter paper strips used to evaluate tear quantity

Front 387

sclera

Back 387

the "white" part of the eye; covers the posterior 5/6 of the fibrous tunic

Front 388

scleritis

Back 388

inflammation of the sclera

Front 389

scotoma

Back 389

area of absent vision or an area of depressed sensitivity in the visual field

Front 390

second-degree fusion

Back 390

-flat fusion
-two similar objects are seen as one object

Front 391

seconds of arc

Back 391

measurement units for recording stereopsis results

Front 392

senile ptosis

Back 392

age related drooping of an eyelid

Front 393

sensory fusion

Back 393

process by which a single image is perceived from two separate ocular images

Front 394

sickle cell disease

Back 394

systemic inherited blood disorder that affects the red blood cells

Front 395

sickle cell retinopathy

Back 395

neovascularization in the eye as a result of sickle cell disease

Front 396

silicone/acrylate (S/A)

Back 396

material used in the first successful GP lenses

Front 397

sinuses

Back 397

air spaces within bones in the head

Front 398

slit-lamp (biomicroscope)

Back 398

a microscope with specialized light source used to examine the eye

Front 399

slit-lamp examination

Back 399

examination of the eye performed using a biomicroscope

Front 400

soft contact lenses

Back 400

flexible lenses made from materials that absorb and bind water into its molecular structure

Front 401

soft perm

Back 401

styrene-based materials used for GP lenses

Front 402

sphincter muscle

Back 402

responsible for the closing of the pupil

Front 403

sphygomanometer

Back 403

-blood pressure cuff
-a cuff with two tubes attached to the bladder: one attache to the manometer, which registers the pressure, and the other is attached to a bulb used to inflate the bladder

Front 404

spud

Back 404

instrument used to peel the foreign body from the cornea

Front 405

squamous cell carcinoma

Back 405

second most common malignant eye tumor, as a result of excessive exposure to sunlight

Front 406

static perimetry

Back 406

target stationary and is presented in lighter or darker increments during visual field testing

Front 407

stereo vision

Back 407

use of two eyes in looking at an object to gain stereopsis

Front 408

stereopsis

Back 408

ability to see or appreciate depth using both eyes; highest degree of depth perception (third-degree fusion)

Front 409

sterilization

Back 409

to free objects from living micro-organisms by subjecting the objects to intense heat or chemical action

Front 410

steroid

Back 410

a drug used to reduce inflammation

Front 411

stethoscope

Back 411

instrument that carries sounds of the body to the examiner's ear

Front 412

strabismus

Back 412

ocular misalignment due to an imbalance of the extraocular muscles

Front 413

stroma

Back 413

third layer of the cornea; 90% of the cornea

Front 414

stye (external hordeolum)

Back 414

an infection located in an eyelash follicle

Front 415

subconjunctival hemorrhage

Back 415

spontaneous bleeding from a blood vessel under the conjunctiva and the episclera

Front 416

subcutaneous areola layer

Back 416

eyelid layer directly below the upper layer

Front 417

submuscular areola layer

Back 417

eyelid layer that contains most of the major nervous and circulatory supplies to the lids

Front 418

superimposition

Back 418

overlapping of two dissimilar onjects (first-degree fusion)

Front 419

superior

Back 419

one of the four principle anatomical directions; toward the head

Front 420

sutures

Back 420

lines where orbital bones are fused together

Front 421

sympathomimetric agents

Back 421

topical glaucoma medication used to increase aqueous flow

Front 422

synapse

Back 422

small gap between the axon of one cell and the dendrite of the next cell

Front 423

synechia (anterior)

Back 423

occurs during uveitis, when the swollen iris adheres to peripheral cornea (iridocyclitis)

Front 424

synechia (posterior)

Back 424

occurs during uveitis when the swollen iris adheres to the lens capsule

Front 425

Systemic Lupus Erythematosus (SLE)

Back 425

systemic chronic inflammatory disease that affects various parts of the body

Front 426

systolic pressure

Back 426

the first and largest number of a blood pressure reading; reflects the amount of force on artery walls when the heart beats

Front 427

tarsal plate

Back 427

responsible for the shape and rigidity of the eyelids (both upper and lower)

Front 428

tear break-up time

Back 428

the amount of time it takes for the tear film on the cornea to break up

Front 429

tetracaine hydrochloride

Back 429

chemical compound closely related to procaine, used as a local anesthetic (generic name for pontocaine and anacel)

Front 430

thimerosal

Back 430

a mercury-based preservative used in contact lens solution

Front 431

third-degree fusion

Back 431

stereopsis

Front 432

thrombus

Back 432

blood clot

Front 433

tonometer

Back 433

instrument used to measure IOP
4 types:
Goldmann (applanation)
tono-Pen
noncontact
indentation (Schoitz)

Front 434

Goldmann (applanation) tonometer

Back 434

attached to a slit lamp and measures the IOP by flattening a small portin of the cornea

Front 435

Tono-Pen tonometer

Back 435

an applanation tonometer that is portable and hand-held

Front 436

noncontact tonometer

Back 436

tonometer uses a puff of air to flatten the cornea, requires no corneal anesthetic

Front 437

indentation (Schoitz) tonometer

Back 437

measures the IOP by indenting a small portion of the cornea

Front 438

tonometry

Back 438

measurment of IOP

Front 439

toric base curve lens

Back 439

back surface toric lens has two different curves on the back and front spherical curve

Front 440

toric peripheral curve lens

Back 440

has one primary spherical back curve with two different peripheral curves on the back (optical zone is elliptical)

Front 441

trabecular meshwork

Back 441

drain for the intraocular fluid

Front 442

transposition

Back 442

changing a prescription written in plus cyl to minus cyl

Front 443

trephine

Back 443

a fine blade that is used to remove the surface epithelium

Front 444

trichromatism

Back 444

normal color vision

Front 445

tri-curve design

Back 445

a noncontact lens that has two peripheral curves

Front 446

trifocal

Back 446

a lens that provides correction for distance, intermediate, and near

Front 447

Trivex

Back 447

a newer plastic lens which is the lightest weight material and is highly impact-resistant; is also has the same optical properties as crown glass, and CR-39 materials

Front 448

trochlea

Back 448

small bony loop at the front of the orbit

Front 449

tropia

Back 449

constant or actual deviation of an eye

Front 450

truncation

Back 450

portion of contact lens is removed producing different diameters in the horizontal and vertical meridians

Front 451

tunics

Back 451

three concentric spheres that make up the globe: fibrous, nervous, and vascular

Front 452

fibrous tunic

Back 452

outermost layer, comprised of the cornea and the sclera

Front 453

nervous tunic

Back 453

innermost layer, which consists of the retina and the retinal pigment epithelium (RPE)

Front 454

vascular tunic

Back 454

also called the "uvea", is the middle layer of the globe and consists of the iris, ciliary body, and choroid

Front 455

uveal tract

Back 455

contains the pigmented, vascular layers of the eye (i.e. anterior iris, ciliary body, and posterior choroid)

Front 456

uveitis

Back 456

inflammation of the uveal tract
4 types:
heterochromic
lens-induced
posterior
anterior

Front 457

heterochromic uveitis

Back 457

a unilateral low-grade infection of the iris and ciliary body, in which affected iris appears lighter

Front 458

lens-induced uveitis

Back 458

occurs after the lens capsule has been torn

Front 459

posterior uveitis

Back 459

inflammation of the choroid

Front 460

anterior uveitis

Back 460

inflammation of the iris and ciliary body

Front 461

vergence

Back 461

movements of the two eyes in opposite directions

Front 462

versions

Back 462

binocular eye movements in the same direction

Front 463

vertex distance

Back 463

measurement from the corneal surface of the eye to the eyeglasses correction

Front 464

vision therapy/vision training

Back 464

process during which patients are given practice and feedback that teaches them to develop or enhance their visual skills

Front 465

visual abilities

Back 465

skills that give us the power of means to locate, identify, and remember what we see

Front 466

visual acuity

Back 466

ability of the eye to resolve detail

Front 467

visual efficiency

Back 467

includes accommodation, binocular vision, and ocular motor skills

Front 468

visual field

Back 468

extent of space visible to an eye in a given position

Front 469

visual processing

Back 469

includes directionality, visual spatial skills, visual analysis skills, and visual motor integration

Front 470

vitrectomy

Back 470

surgical procedure that removes and replaces cloudy vitreous

Front 471

vitreous humor

Back 471

transparent, thick, jelly-like substance that fills the posterior 2/3 of the eye, between the lens and the retina

Front 472

xanthelasma

Back 472

small, yellowish fatty deposits that occur on the eyelids, usually on the medial side

Front 473

YAG Laser capsulotomy

Back 473

a procedure used to remove the capsular opacity after cataract surgery