Medical Definitions Chap.17

Front 1

Accommodation

Back 1

Normal adjustment of the eye to focus on objects from far to near. When this occurs, the ciliary body adjusts the lens (rounding it) and the pupil constricts. When the eye focuses from near to far, the ciliary body flattens the lens and the pupil dilates

Front 2

Anterior chamber

Back 2

Area behind the cornea and in front of the lens and Iris. It contains aqueous humour

Front 3

Aqueous humour

Back 3

Fluid produced by the ciliary body and found in the anterior chamber. A humor (Latin humidus meaning moist) is any body fluid, including blood and lymph

Front 4

Biconvex

Back 4

Consisting of two surfaces that are rounded, elevated, and curved evenly, like a part of a sphere. The lens of the eye is a biconvex body

Front 5

Choroid

Back 5

Middle, vascular layer of the eye, between the retina and the sclera

Front 6

Ciliary body

Back 6

Structure surrounding the lens that connects the iris to the choroid. It contains ciliary muscles, which control the shape of the lens, and it secretes aqueous humour

Front 7

Cone

Back 7

Photoreceptor cell in the retina that transforms light energy into a nerve impulse. Cones are responsible for colour and central vision

Front 8

Conjunctiva

Back 8

Delicate membrane lining the eyelids and covering the eyeball up to the cornea

Front 9

Cornea

Back 9

Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball.

Front 10

Fovea centralis

Back 10

Tiny pit or depression in the retina that is the region of clearest vision

Front 11

Fundus of the eye

Back 11

Posterior, inner part of the eye; visualized with an ophthalmoscope

Front 12

Iris

Back 12

Pigmented (coloured) layer that opens and closes to allow more or less light into the eye. The central opening of the iris is the pupil

Front 13

Lens

Back 13

Transparent, biconvex body behind the pupil of the eye. It bends (refracts) light rays to bring them into focus on the retina

Front 14

Macula

Back 14

Small oval region on the retina near the optic disc; contains the fovea centralis, which is the area of clearest vision

Front 15

Optic chiasm

Back 15

Point at which the optic nerve fibres cross into the brain

Front 16

Optic disc

Back 16

Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibres, no rods or cones, and is thus sensitive to light

Front 17

Optic nerve

Back 17

Cranial nerve carrying impulses from the retina to the brain (cerebral cortex)

Front 18

Pupil

Back 18

Central opening of the eye, surrounded by the iris, through which light rays pass. It appears dark

Front 19

Refraction

Back 19

Bending of light rays by the cornea, lens, and fluids of the eye to bring the Rays into focus on the retina. Refract means to break (-fract) Break (re-)

Front 20

Retina

Back 20

Light sensitive nerve cell layer of the eye containing photoreceptor cells (rods and cones)

Front 21

Rod

Back 21

Photoreceptor cell the retina essential for vision in low light and peripheral vision

Front 22

Sclera

Back 22

Tough, white outer coat of the eyeball

Front 23

Thalamus

Back 23

Relay centre of the brain. Optic nerve fibres pass through the thalamus on their way to the cerebral cortex

Front 24

Vitreous humour

Back 24

Soft, jelly-like material behind the lens in the vitreous chamber; helps maintain the shape of the eyeball. Often referred to as the vitreous

Front 25

Auditory canal

Back 25

Channel that leads from the pinna to the eardrum

Front 26

Auditory meatus

Back 26

Auditory canal

Front 27

Auditory nerve fibres

Back 27

Carry impulses from the inner ear to the brain (cerebral cortex). These fibres compose the vestibulocochlear nerve (cranial nerve VIII)

Front 28

Auditory tube

Back 28

Channel between the middle ear and the nasopharynx; eustachian tube

Front 29

Auricle

Back 29

Temperature Reading part of the external ear, or pinna

Front 30

Cerumen

Back 30

Waxy substance secreted by the external ear; ear wax

Front 31

Cochlea

Back 31

Snail shell-shaped, spirally wound tube in the inner ear; contains hearing-sensitive receptor cells

Front 32

Endolymph

Back 32

Fluid within the Labyrinth of the inner ear

Front 33

Eustachian tube

Back 33

Auditory tube

Front 34

Incus

Back 34

Second ossicle small bone of the middle ear; incus means anvil

Front 35

Labyrinth

Back 35

Maze like series of canals of the inner ear. This includes the cochlea, Vestibule, and semicircular canals

Front 36

Malleus

Back 36

First ossicle of the middle ear, malleus means hammer

Front 37

Organ of Corti

Back 37

Sensitive auditory receptor area found in the cochlea of the inner ear

Front 38

Ossicle

Back 38

Small bone of the ear; includes the malleus, incus and stapes

Front 39

Oval window

Back 39

Membrane between the middle ear and the inner ear

Front 40

Perilymph

Back 40

Fluid contained in the Labyrinth of the inner ear

Front 41

Pinna

Back 41

Auricle; flap of the ear

Front 42

Semicircular canals

Back 42

Passages in the inner ear associated with maintaining equilibrium

Front 43

Stapes

Back 43

Third ossicle of the middle ear. Stapes means stirrup

Front 44

Tympanic membrane

Back 44

Membrane between the outer and the middle ear; also called the eardrum

Front 45

Vestibule

Back 45

Central cavity of the labyrinth, connecting the semicircular canals and the cochlea. The vestibule contains two structures, the saccule and utricle, that help to maintain equilibrium

Front 46

Aque/o

Back 46

Water

Front 47

Blephar/o

Back 47

Eyelid

Front 48

Conjunctiv/o

Back 48

Conjunctiva

Front 49

Cor/o pupill/o

Back 49

Pupil

Front 50

Corne/o kerat/o

Back 50

Cornea

Front 51

Cycl/o

Back 51

Ciliary body or muscle of the eye

Front 52

Dacry/o Lacrim/o

Back 52

tears, tear duct

Front 53

Ir/o irid/o

Back 53

Iris (coloured portion of the eye around the pupil)

Front 54

Ocul/o

Back 54

Eye

Front 55

Ophthalm/o

Back 55

Eye

Front 56

Opt/o optic/o

Back 56

Eye, vision

Front 57

Palpebr/o

Back 57

Eyelid

Front 58

Papill/o

Back 58

Optic disc; nipple-like

Front 59

Phac/o phak/o

Back 59

Lens of the eye

Front 60

Pupill/o

Back 60

Pupil

Front 61

Retin/o

Back 61

Retina

Front 62

Scler/o

Back 62

Sclera (white of the eye); hard

Front 63

Uve/o

Back 63

Uvea; vascular layer of the eye (Iris, ciliary body, and choroid)

Front 64

Virtre/o

Back 64

Glassy

Front 65

Ambly/o

Back 65

Dull, dim

Front 66

Dipl/o

Back 66

Double

Front 67

Glauc/o

Back 67

Gray

Front 68

Mi/o

Back 68

Smaller, less

Front 69

Mydr/o

Back 69

Widen, and enlarge

Front 70

Nyct/o

Back 70

Night

Front 71

Phot/o

Back 71

Light

Front 72

Presby/o

Back 72

Old age

Front 73

Scot/o

Back 73

Darkness

Front 74

Xer/o

Back 74

Dry

Front 75

Acous/o audit/o

Back 75

Hearing

Front 76

Audi/o

Back 76

Hearing; the sense of hearing

Front 77

Aur/o auricul/o

Back 77

Ear

Front 78

Cochle/o

Back 78

Cochlea

Front 79

Mastoid/o

Back 79

Mastoid process

Front 80

Myring/o tympan/o

Back 80

Eardrum, tympanic membrane

Front 81

Ossicul/o

Back 81

Ossicle

Front 82

Ot/o

Back 82

Ear

Front 83

Salping/o

Back 83

Eustachian tube, auditory tube

Front 84

Staped/o

Back 84

Stapes (third bone of the middle ear)

Front 85

Vestibul/o

Back 85

Vestibule

Front 86

-opia -opsia

Back 86

Vision

Front 87

-tropia

Back 87

To turn

Front 88

-acusis -cusis

Back 88

Hearing

Front 89

-meter

Back 89

Instrument to measure

Front 90

-otia

Back 90

Ear condition

Front 91

Astigmatism

Back 91

Defective curvature of the cornea or lens of the eye

Front 92

Hyperopia (hypermetropia)

Back 92

Farsightedness

Front 93

Myopia

Back 93

Nearsightedness

Front 94

Presbyopia

Back 94

Impairment of vision as result of old age

Front 95

Cataract

Back 95

Clouding of the lens, causing decreased vision

Front 96

Chalazion

Back 96

Small, hard, cystic mass (granuloma) of the eyelid

Front 97

Diabetic retinopathy

Back 97

Disease of the retina caused by diabetes mellitus, exudates is fluid leaking from the blood

Front 98

Glaucoma

Back 98

Increased intraocular pressure results in damage to the retina and optic nerve with loss of vision, glaucoma is diagnosed by means of tonometry, trabeculoplasty laser therapy for chronic open-angle glaucoma causes scarring in the drainage angle, improving aqueous humour outflow and reducing introcular pressure,

Front 99

Blepharitis

Back 99

Inflammation of the eyelid, causing redness, crusting, and swelling along lid margins

Front 100

Dacryocystitis

Back 100

Blockage, inflammation, and infection of the nasolacrimal duct and lacrimal Sac, causing redness and swelling in the region between the nose and the lower lid

Front 101

Ectropion

Back 101

Outward sagging and eversion of the eyelid, leading to improper lacrimation and corneal drying and ulceration

Front 102

Entropion

Back 102

Inversion of the eyelid, causing the lashes to rub against the eye; corneal abrasion may result

Front 103

Hordeolum (stye)

Back 103

Small, superficial white nodule along lid margin due to infection of a sebaceous gland

Front 104

Ptosis

Back 104

Drooping of upper lid margin from neuromuscular problems or trauma

Front 105

Xanthelasma

Back 105

Raised yellowish plaque on eyelid caused by a lipid disorder (xanth/o = yellow, -elasma = plate)

Front 106

Macular degeneration

Back 106

Progressive damage to the macula of the retina, drusen is atrophy and degeneration of retinal cells and deposits of clumps of extracellular debris

Front 107

Nystagmus

Back 107

Repetitive rhythmic movements of one or both eyes

Front 108

Retinal detachment

Back 108

Two layers of the retina separate from each other, photosia are bright flashes of light, floaters are black spots or filmy shapes,

Front 109

Strabismus

Back 109

Abnormal deviation of the eye, (esotropia one eye turns inward cross-eyed) (exotropia one eye turns outward wall-eye) (hypertropia upward deviation of One Eye) (hypotropia downward deviation of One Eye) (amblyopia partial loss of vision from lazy eye) (diplopia double vision)

Front 110

Fluorescein angiography

Back 110

Intravenous injection of fluorescein (a dye) followed by serial photographs of the retina through dilated pupils

Front 111

Ophthalmoscopy

Back 111

Visual examination of the interior of the eye

Front 112

Optical coherence tomography (OCT)

Back 112

Non-invasive Imaging technique using light waves to take cross-sectional pictures of the retina

Front 113

Slit lamp microscopy

Back 113

Examination of anterior ocular structures and under microscopic magnification

Front 114

Visual Acuity test

Back 114

Clarity of vision is assessed

Front 115

Visual field test

Back 115

Measurement of the entire scope of vision (peripheral and Central)

Front 116

Enucleation

Back 116

Removal of the entire eyeball

Front 117

Keratoplasty

Back 117

Surgical repair of the cornea

Front 118

Laser photocoagulation

Back 118

Intense, precisely focussed Light Beam (argon laser) creates an inflammatory reaction that seals retinal tears and leaky retinal blood vessels

Front 119

LASIK

Back 119

Use of an excimer laser to correct errors of refraction (myopia, hyperopia, and astigmatism)

Front 120

Phacoemulsification

Back 120

Cataract removal surgery in which ultrasonic vibrations break up the lens; the pieces are then aspirated through the ultrasonic probe

Front 121

Scleral buckle

Back 121

Suture of a silicone band to the sclera over a detached portion of the retina

Front 122

Vitrectomy

Back 122

Removal of the vitreous humour

Front 123

Acoustic neuroma

Back 123

Benign tumour arising from the acoustic vestibulocochlear nerve (8th cranial nerve) in the brain

Front 124

Cholesteatoma

Back 124

Collection of skin cells and cholesterol in a Sac within the middle ear

Front 125

Deafness

Back 125

Loss of the ability to hear, nerve deafness (sensorineural hearing loss) results from the impairment of the cochlea or auditory acoustic nerve. Conductive deafness results from the impairment of sound wave transmission from the external ear to the cochlea

Front 126

Meniere disease

Back 126

Disorder of the Labyrinth of the inner ear; elevated endolymph pressure within the cochlea (cochlear hydrops) and semicircular canals and (vestibular hydrops)

Front 127

Otitis media

Back 127

Inflammation of the middle ear, acute Hostess media is an infection of the middle ear often following an upper respiratory infection pain and fever with redness and loss of mobility of the tympanic membrane occur, as bacteria invade the middle ear, pus formation occurs suppurative otitis media, serous otitis media is an noninfectcious inflammation with accumulation of serous fluid

Front 128

Otosclerosis

Back 128

Hardening of the Bony tissue of the middle ear, (ankylosis stiffening) (prosthesis artificial part) (fenestrated opened)

Front 129

Tinnitus

Back 129

Sensation of noises in the ears without an external source

Front 130

Vertigo

Back 130

Sensation of irregular or whirling motion either of oneself or of external objects, in benign paroxysmal positional vertigo a patient experiences repeated, brief episodes (proximal means sudden onset with a short duration) of vertigo

Front 131

Audiometry

Back 131

Testing the sense of hearing with an audiometer

Front 132

Cochlear implant procedure

Back 132

Surgical incision of a device that allows sensorineural hearing impaired persons to understand speech

Front 133

Ear thermometry

Back 133

Measurement of the temperature of the tympanic membrane by detection of infrared radiation from the eardrum

Front 134

Otoscopy

Back 134

Visual examination of the ear canal with an otoscope

Front 135

Tuning fork test

Back 135

Cast of ear conduction using a vibration Source (tuning fork), (Rinne test; examiner places the base of the vibrating floor contains the patient's mastoid bone and in front of the auditory meatus) (weber test; The Tuning Fork is placed on the centre of the forehead)

Front 136

Blepharoptosis

Back 136

Also called ptosis. This condition may be caused by abnormalities of the eyelid muscle or by nerve damage

Front 137

Conjunctivitis

Back 137

Commonly called pinkeye. Conjunctivitis occurs when blood vessels dilate from allergens like pollen (allergic conjunctivitis), bacterial infection (bacterial conjunctivitis), or virus (viral conjunctivitis)

Front 138

Anisocoria

Back 138

Anis/o means unequal, anisocoria may be an indication of neurologic injury or disease

Front 139

Iritis

Back 139

Characterized by pain, sensitivity to light, and lacrimation. A corticosteroid is prescribed to reduce inflammation

Front 140

Iridectomy

Back 140

A portion of the iris is removed to improve drainage of aqueous humour or to extract a foreign body

Front 141

Ophthalmologist

Back 141

Medical doctor who specializes in treating disorders of the eye

Front 142

Optometrist

Back 142

Non Medical Professional who can examine eyes to determine vision problems and prescribed lenses; a doctor of Optometry O.D.

Front 143

Optician

Back 143

Non Medical Professional who grinds lenses and fits glasses but cannot prescribe lenses

Front 144

Papilledema

Back 144

The suffix -edema means swelling, this condition is associated with increased intracranial pressure and hyperemia increase blood flow in the region of the optic disc

Front 145

Phacoemulsification

Back 145

Technique of cataract extraction using ultrasound vibrations to fragment emulsify the lens and aspirate the pieces from the eye

Front 146

Aphakia

Back 146

This condition may be congenital, but most often is the result of extraction of a cataract-clouded lens without placement of an artificial lens pseudophakia

Front 147

Retinitis

Back 147

Retinitis Pigmentosa is a genetic disorder pigmented scar forms on the retina that destroys retinal rods. Decreased vision and night blindness nyctalopia occur

Front 148

Hypersensitive Renopathy

Back 148

Changes such as a narrowing of arterioles, microaneurysms, hemorrhages, and exudate fluid leakage are found on examination of the fundus

Front 149

Intravitreal

Back 149

Intravitreal injections are a method of treatment for ophthalmologic conditions such as diabetic retinopathy and macular degeneration

Front 150

Amblyopia

Back 150

The suffix -opia means Vision. Amblyopia is decreased visual Acuity often in a single eye and appearing in children. It can occur from misalignment of the eyes, such as with strabismus, and it is known as lazy eye

Front 151

Glaucoma

Back 151

Here, -oma means mass or collection of fluid aqueous humour. The term comes from the dollar gray-green colour of the affected eye in advance cases

Front 152

Miosis

Back 152

Contraction of the pupil. A miotic is a drug (such as pilocarpine) that causes the pupil to contract

Front 153

Mydriasis

Back 153

Enlargement of the pupils. Tropicamide, atropine, and cocaine cause dilation, or enlargement, of pupils

Front 154

Nyctalopia

Back 154

-opia means vision; -al comes from greek ala, meaning blindness. Night blindness is poor vision at night but good Vision on Bright Days. Deficiency of vitamin A leads to Nyctalopia

Front 155

Photophobia

Back 155

Sensitivity to light

Front 156

Scotoma

Back 156

Area of decreased Vision surrounded by an area of normal vision; a blind spot. This can result from damage to the retina or the optic nerve

Front 157

Hemianopia

Back 157

Absence of vision in half of the visual field (space of vision of each eye). Stroke victims frequently have damage to the brain on one side of the visual cortex and experience Hemianopia (the visual loss is in the right or left visual field of both eyes)

Front 158

Esotropia

Back 158

Inward (eso-) turning of an eye. Exotropia is an outward turning of an eye. These conditions are examples of strabismus keep acting eye muscle so that both eyes cannot be focussed on the same point at the same time

Front 159

Audiologist

Back 159

A healthcare professional specializing in the evaluation and Rehabilitation of people with hearing loss

Front 160

Mastoiditis

Back 160

The mastoid process is the posterior portion of the temporal bone extending downward behind the external auditory meatus. Mastoiditis, caused by bacterial infection, spreads from the middle ear

Front 161

Otolaryngologist

Back 161

An otolaryngologist is a medical doctor specializing in the ear, nose, and throat

Front 162

Salpingopharyngeal

Back 162

In the context of female reproductive Anatomy, Salping/o means the fallopian tubes

Front 163

Stapedectomy

Back 163

After stapedectomy a prosthetic device is used to connect the Incus and the oval window

Front 164

Tympanoplasty

Back 164

Surgical reconstruction of the bones of the middle ear with reconnection of the eardrum to the oval window

Front 165

Hyperacusis

Back 165

Abnormally acute sensitivity to sounds

Front 166

Presbycusis

Back 166

This type of nerve deafness occurs with the process of Aging

Front 167

Macrotia

Back 167

Abnormally large ears; congenital anomaly