Chapter 11 Medical Chapter 11 Medical TerminologyTerminology

andandChapter 10 Body Chapter 10 Body

Structures:Structures:

SPECIAL SENSESSPECIAL SENSES

Functions of the EyesFunctions of the Eyes – – receive images and transmit to receive images and transmit to

brainbrainreceptor organs of sightreceptor organs of sight Optic: Optic:

pertaining to pertaining to eye or sighteye or sight

Ocular: Ocular: pertaining to pertaining to the eyethe eye Extraocular: Extraocular:

outside the outside the eyeballeyeball

Intraocular: Intraocular: within the within the eyeballeyeball

Structures of the Structures of the EyeEye

ADNEXA – ADNEXA – accessory accessory structuresstructures OrbitOrbit Eye MusclesEye Muscles Eyelids Eyelids EyelashesEyelashes ConjunctivaConjunctiva Lacrimal Lacrimal

ApparatusApparatuswww.ipo.tue.nl/.../seminar-2%20human/ sld015.htm

What structure What structure contains and contains and protects the protects the eyeball and its eyeball and its associated associated muscles, blood muscles, blood vessels, and vessels, and nervesnerves

ORBITORBIT FrontalFrontal SphenoidSphenoid EthmoidEthmoid MaxillaMaxilla ZygomaZygoma LacrimalLacrimal PalatinePalatine

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Muscles of the EyeMuscles of the Eye 6 Major muscles 6 Major muscles

attached to attached to each eyeeach eye

Superior/Superior/Inferior RectusInferior Rectus

Superior/Superior/Inferior ObliqueInferior Oblique

Lateral/Medial Lateral/Medial RectusRectus

Binocular means both eyes working together.

Eyelids:Eyelids: protect the protect the eyeball from foreign eyeball from foreign matter, excessive matter, excessive light, and impactlight, and impact

CanthusCanthus: angle where : angle where upper/lower eyelids meetupper/lower eyelids meet Inner CanthusInner Canthus Outer CanthusOuter Canthus

Conjunctiva:Conjunctiva: lines the underside lines the underside

of each eyelid and of each eyelid and provides provides protective protective covering over covering over exposed surface of exposed surface of eyeballeyeball

The Lacrimal ApparatusThe Lacrimal Apparatus – – structures that produce, store, structures that produce, store,

and remove tearsand remove tears Lacrimal Glands: secrete lacrimal fluid Lacrimal Glands: secrete lacrimal fluid

to maintain moisture on the anterior to maintain moisture on the anterior surface of the eyeballsurface of the eyeball

Lacrimal Canaliculi: ducts at the inner Lacrimal Canaliculi: ducts at the inner canthus of each eye – collect tears and canthus of each eye – collect tears and drain them into the lacrimal sacdrain them into the lacrimal sac

Lacrimal sac: an enlargement of the Lacrimal sac: an enlargement of the upper portion of the lacrimal ductupper portion of the lacrimal duct

Lacrimal duct: passageway that drains Lacrimal duct: passageway that drains lacrimal fluid into the noselacrimal fluid into the nose

Eyebrows and EyelashesEyebrows and Eyelashes

Prevent foreignPrevent foreign

matter from reaching the eyematter from reaching the eye Cilia – small hairs that areCilia – small hairs that are

located along the edgeslocated along the edges

of the eyelids (eyelashes)of the eyelids (eyelashes)

The Eyeball The Eyeball - - globeglobe

Made up of 3 Made up of 3 layerslayers ScleraSclera ChoroidChoroid RetinaRetina

Interior of eye is Interior of eye is divided into divided into anterior/posterior anterior/posterior segmentssegments

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The ScleraThe Sclera – – the white of the the white of the eyeeye

Outer layer of eyeOuter layer of eye Maintains shape of Maintains shape of

the eye and protects the eye and protects the delicate inner the delicate inner layers of tissuelayers of tissue Cornea: transparent Cornea: transparent

anterior portion of the anterior portion of the sclerasclera

Provides most of the Provides most of the optical power of the optical power of the eyeeye

The Uveal The Uveal TractTract

The vascular layer of eyeThe vascular layer of eye Choroid:Choroid: opaque (light opaque (light

cannot pass through it) cannot pass through it) middle layer of the eyeball – middle layer of the eyeball – provides blood supply for provides blood supply for entire eyeentire eye

Iris:Iris: colored layer that colored layer that surrounds pupil – it’s surrounds pupil – it’s muscles control amount of muscles control amount of light entering eye – decrease light entering eye – decrease - muscles contract making - muscles contract making opening smaller (visa versa)opening smaller (visa versa)

Pupil:Pupil: black circular opening black circular opening in center of iris – permits in center of iris – permits light to enter eyelight to enter eye

Lens:Lens: focuses images on the focuses images on the retina – located behind iris retina – located behind iris and pupiland pupil

Ciliary Body:Ciliary Body: located located within the choroid, set of within the choroid, set of muscles and ligaments muscles and ligaments that adjust lens to refine that adjust lens to refine the focus of light rays on the focus of light rays on the retinathe retina

Near-by objects = thickerNear-by objects = thicker Distance objects = thinnerDistance objects = thinner

The RetinaThe Retina Nerve layer located Nerve layer located between the posterior between the posterior chamber and the chamber and the choroid layer at the choroid layer at the back of the eyeback of the eye

Contains light Contains light sensitive rods sensitive rods (black/white (black/white receptors) and cones receptors) and cones (color receptors)(color receptors) Receive images and Receive images and

convert them into convert them into nerve impulsesnerve impulses

Optic disk: (blind Optic disk: (blind spot) – contains no spot) – contains no rods/cones – nerve rods/cones – nerve endings of retina endings of retina gather to form gather to form optic optic nerve nerve which which transmits nerve transmits nerve impulses from the impulses from the retina to the brainretina to the brain

The Anterior Segment The Anterior Segment – – front 1/3 of eyefront 1/3 of eye

Divided into anteriorDivided into anteriorand posterior and posterior chamberschambers

Anterior chamberAnterior chamber behind the cornea inbehind the cornea in

front of the irisfront of the iris Posterior chamberPosterior chamber

Between the back of the iris and Between the back of the iris and the front of the lensthe front of the lens

These chambers filled with These chambers filled with aqueus humor (fluid)aqueus humor (fluid) Nourishes intraocular structures Nourishes intraocular structures Constantly filtered and drained which regulates Constantly filtered and drained which regulates

intraocular pressure (IOP = btwn 12 & 21 mm Hg)intraocular pressure (IOP = btwn 12 & 21 mm Hg)

The Posterior The Posterior Segment – Segment – posterior 2/3 of posterior 2/3 of

eyeeye Aids in maintaining theAids in maintaining the

shape of the eyeshape of the eye Contains Contains vitreous vitreous

humorhumor Lined with retina and Lined with retina and

it’s related structuresit’s related structures

Normal Action of the EyeNormal Action of the Eye Accommodation:Accommodation: the eyes make the eyes make

adjustments for seeing at various distancesadjustments for seeing at various distances Includes constriction or dilation of the pupil, Includes constriction or dilation of the pupil,

movement of the eye, and changes in the shape movement of the eye, and changes in the shape of the lensof the lens

Convergence:Convergence: simultaneous inward simultaneous inward movement of both eyes – in an effort to movement of both eyes – in an effort to maintain single binocular vision as an object maintain single binocular vision as an object comes nearercomes nearer

Visual Acuity:Visual Acuity: the ability to distinguish the ability to distinguish object details and shape at a distanceobject details and shape at a distance Normal vision = 20/20Normal vision = 20/20 Snellen Chart: used to measure visual acuitySnellen Chart: used to measure visual acuity

GlaucomaGlaucoma

Glaucoma is the increase of the IOP (intra-ocular pressure)

Macular DegenerationMacular Degeneration

Loss of central vision over a period of time but,not total blindness

Pathology of the Eyes - Pathology of the Eyes - EYELIDSEYELIDS

Blepharoptosis Blepharoptosis (A)(A)

Ectropion (C)Ectropion (C) Entropion (B)Entropion (B) Hordeolum: (D)Hordeolum: (D)

AB

C D

Functions of the EarsFunctions of the Ears Receive sound Receive sound

impulses and impulses and transmit them to the transmit them to the brainbrain Inner also helps Inner also helps

maintain balancemaintain balance

Auditory:Auditory: pertaining to the pertaining to the sense of hearingsense of hearing

Acoustic:Acoustic: relating relating to sound or hearingto sound or hearing

Structures of the EarStructures of the Ear

The Outer EarThe Outer Ear The Middle EarThe Middle Ear

The Auditory The Auditory OssiclesOssicles

The Eustachian The Eustachian TubesTubes

The Inner EarThe Inner Ear

The Outer The Outer EarEar

Pinna:Pinna: auricle – auricle – External portionExternal portion Catches soundCatches sound

waves and transmitswaves and transmitsthem into the them into the external auditory canalexternal auditory canal(EAC)(EAC)

EAC:EAC: transmits sound waves from pinna to middle transmits sound waves from pinna to middle earear

What is the name for the sticky yellow-brown What is the name for the sticky yellow-brown substance that functions to prevent bacteria and substance that functions to prevent bacteria and dust from entering the middle ear??dust from entering the middle ear??

CERUMEN (earwax)CERUMEN (earwax)

The Middle The Middle EarEar

Tympanic Membrane (eardrum)Tympanic Membrane (eardrum) Transmits sound by vibratingTransmits sound by vibrating Surrounded by hollow air spaces – Surrounded by hollow air spaces – mastoid mastoid

cells cells (which can easily become involved in (which can easily become involved in a middle ear infection)a middle ear infection)

The Auditory The Auditory OssiclesOssicles 3 small bones in the 3 small bones in the

middle earmiddle ear Transmit sound waves Transmit sound waves

from the eardrum to the from the eardrum to the inner ear by vibrationinner ear by vibration

Named for their shapeNamed for their shape

Malleus:Malleus: hammer hammer

Incus:Incus: anvil anvil

Stapes:Stapes: stirrup stirrup

malleus

incus

stapes

The Inner The Inner Ear-Ear-

labyrinthlabyrinth

Contains sensory receptors for Contains sensory receptors for hearing and balancehearing and balance Cochlea:Cochlea: spiral shaped passage that leads spiral shaped passage that leads

from the oval windowfrom the oval window Cochlear duct:Cochlear duct: filled with fluid that vibrates when filled with fluid that vibrates when

sound waves strike itsound waves strike it Organ of Corti:Organ of Corti: receptor site receptor site

that receives vibrations and that receives vibrations and relays them to the auditory relays them to the auditory nerve fibers that transmit nerve fibers that transmit them to the auditory center them to the auditory center of the cerebral cortex, where of the cerebral cortex, where they are interpreted and heardthey are interpreted and heard

Semicircular canals:Semicircular canals: helps maintain helps maintainequilibriumequilibrium

Normal Action of the Normal Action of the EarsEars

Air conduction:Air conduction: sound waves enter the ear sound waves enter the ear through the pinna, travel down the auditory through the pinna, travel down the auditory canal, and strike the TM between the outer canal, and strike the TM between the outer and middle earand middle ear

Bone conduction:Bone conduction: as the eardrum vibrates, it as the eardrum vibrates, it moves the auditory ossicles and these moves the auditory ossicles and these conduct sound waves through the middle conduct sound waves through the middle earear

Sensorineural conduction:Sensorineural conduction: sound vibrations sound vibrations reach the inner ear via the oval window reach the inner ear via the oval window where the structures of the inner ear where the structures of the inner ear receive the sound waves and relay them to receive the sound waves and relay them to the brainthe brain

Pathology of the EarsPathology of the Ears Outer EarOuter Ear

Otalgia: earacheOtalgia: earache Otitis: inflammation of the earOtitis: inflammation of the ear Otomycosis: swimmer’s earOtomycosis: swimmer’s ear

Middle EarMiddle Ear Eustachitis: inflammation of the eustachian tubeEustachitis: inflammation of the eustachian tube MastoiditisMastoiditis Otosclerosis: ankylosing of the bones of the middle ear Otosclerosis: ankylosing of the bones of the middle ear

= hearing loss= hearing loss Otitis MediaOtitis Media

Inner EarInner Ear Meniere’s syndrome: vertigo, fluctuating hearing loss, Meniere’s syndrome: vertigo, fluctuating hearing loss,

tinnitus (ringing or buzzing in the ears)tinnitus (ringing or buzzing in the ears) Hearing LossHearing Loss

DeafnessDeafness Noise-Induced hearing lossNoise-Induced hearing loss

Diagnostic Procedures of the Diagnostic Procedures of the EarsEars

Audiometry:Audiometry: use of audiometer to use of audiometer to measure hearingmeasure hearing

Speech audiometry:Speech audiometry: measures the measures the threshold of speech reception and threshold of speech reception and speech discriminationspeech discrimination

MonauralMonaural: testing involving one ear: testing involving one ear Binuaral:Binuaral: testing involving both ears testing involving both ears

audiometry

Left ear - ASRight ear - AD

Both ears - AU

Treatment Procedures of the Treatment Procedures of the EarsEars

Outer EarOuter Ear Otoplasty: surgical repair of the pinna of Otoplasty: surgical repair of the pinna of

the earthe ear Middle EarMiddle Ear

MastoidectomyMastoidectomy TympanocentesisTympanocentesis Tympanostomy tubesTympanostomy tubes

Inner EarInner Ear FenestrationFenestration LabyrinthectomyLabyrinthectomy LabyrinthotomyLabyrinthotomy

otoplastyMastoidectomy

tympanostomy labyrinthectomy