Transcript CRANIAL NERVES

CRANIAL NERVES
DR VINIT K ASHOK
ADJUNCT FACULTY
CRANIAL NERVES
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NERVES COMING OUT/ GOING INTO THE
BRAIN
TOTAL -12 NUMBERED IN ROMAN
NUMERICALS( I-XII)
CARRY IMPULSES TO AND FROM THE
BRAIN
EXIT OR ENTER THE SKULL THROUGH
OPENINGS IN THE SKULL
I AND 11 ARE ATTACHED TO THE
FOREBRAIN
III TO XII ARE ATTACHED TO THE BAIN
STEM
ALL SUPPLY THE STRUCTURES OF THE
HAED AND NECK EXCEPT THE X(
VAGUS) ----VAGABOND -----WANDERS TO
THE ABDOMEN
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I – OLFACTORY
II- OPTIC
III-OCCULOMOTOR
IV-TROCHLEAR
V-TRIGEMINAL( 3 DIVISIONS)
VI –ABDUCENS
VII-FACIAL
VIII-VESTIBULOCOCHLEAR
IX-GLOSSOPHARYNGEAL
X-VAGUS
XI-ACCESSORY
XII-HYPOGLOSSAL
“OH OH OH TO TOUCH AND FEELVERY
GOOD VELVET AH
FORAMINA /OPENINGS FOR THE
CRANIAL NERVES
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I –OLFACTORY FORAMINA
II-OPTIC FORAMEN
III- SUPERIOR ORBITAL FISSURE
IV-SUPERIOR ORBITAL FISSURE
V- 3 DIVISIONS
A) OPTHALMIC- SUPERIOR ORBITAL FISSURE
B) MAXIALLRY-FORAMEN ROTUNDUM
C) MANDIBULAR- FORAMEN OVALE
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VI-INFERIOR ORBITAL FISSURE
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VII- ENTERS THE INT ACCOUSTIC MEATUS---- EXITS THE SKULL THROUGH THE
STYLOMASTOID FORAMEN
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VIII- INT ACCOUSTIC MEATUS
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IX-JUGULAR FORAMEN
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X-JUGULAR FORAMEN
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XI- JUGULR FORAMEN
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XII-HYPOGLOSSAL CANAL
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I-OLFACTORY NERVE-SENSORY NERVES OF SMELL
II - OPTIC NERVE-SENSORY NERVE OF VISION
III- OCCULOMOTOR-( EYE MOVER)-INNERVATES 4 EXTRINSIC MUSCLES OF THE
EYEBALL
1V- TROCLEAR NERVE- ( MEANS PULLEY) –SUPPLIES THE SUPERIOR OBLIQUE MUSCLE
OF THE EYEBALL
V-TRIGEMINAL ( 3 FOLD) –THIS NERVE HAS 3 BRANCHES. SENSORY INNERVATION TO
THE FACE AND MOTOR TO MUSCLES THAT HELP US CHEW( MASTICATE)
VI-ABDUCENS NERVE- IT SUPPLIES THE MUSCLE OF THE EYEBALL THAT ABDUCTS THE
EYE( LATERAL RECTUS)
VII-FACIAL NERVE-INNERVATES MUSCLES OF FACIAL EXPRESSION
VIII-VESTIBULOCOCHLEAR-SENSORY NERVE OF HEARING AND EQUILIBRIUM
IX-GLOSSOPHARYNGEAL NERVE-( MEANS TONGUE AND PHARYNX), STRUCTURES THIS
NERVE INNERVATES
X-VAGUS ( WANDERER)-INNERVATES THE STRUCTURES IN THE THORAX AND ABDOMEN
XI-ACCESSORY- ( ACCESSORY TO THE VAGUS)-SUPPLIES THE TRAPEZIUS AND
STERNOCLEIDOMASTOID
XII-HYPOGLOSSAL( BELOW THE TONGUE)-RUNS INFERIOR TO THE TONGUE AND
SUPPLIES THE TONGUE MUSCLES
SENSORY/MOTOR NERVE
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CRANIAL NERVES --- PURELY
SENSORY / MOTOR / MIXED
 SENSORY NERVE- RECEPTORS---GENARAL SENSATIONS( TOUCH,
PAIN TEMP,PRESSURE,) SPECIAL --SMELL,VISION, HEARING,
EQUILIBRIUM.---CRANIAL NERVE—
BRAIN.( I, II AND VIII) ( AFFERENT
IMPULSES)
 MOTOR NERVE-IMPULSE FROM
THE BRAIN----CRANIAL NERVE ---ACTION----( MUSCLE/GLAND)---EFFERENT IMPULSES( III,IV,VI,XI
AND XII)
 MIXED ( BOTH TYPE OF FIBRES)
NERVES
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MOTOR ( TYPES)
1. VISCERAL MOTOR
( MOTOR NERVE SUPPLY TO
THE VISCERA AND GLANDS)
2. BRANCHIAL MOTOR
MOTOR NERVE SUPPLY OF THE
BRANCHIAL ARCH
MUSCULATURE
3. SOMATIC MOTOR
MOTOR SUPPLY TO ALL OTHER
SKELETAL MUSCLES
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SENSORY
1.VISCERAL SENSORY
A) SPECIAL—TASTE
B) GENERAL---VISCERA—
PAIN,TOUCH,PRESSURE,
TEMP
2.SOMATIC SENSORY
A) SPECIAL- SMELL, VISION
HEARING
B) GENERAL—TOCH ,PAIN
PRESSURE FROM THE
LIMBS, BODY WALL
CRANIAL NERVES WITH
PARASYMPATHETIC FIBRES
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III- OCCULOMOTOR
-1. CONTRICTOR PUPILLAE
2. CILIARIS- CHANGES THE SHAPE OF THE LENS
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VII- FACIAL
1.
TEAR , NASAL AND PALTINE GLANDS
2.
SUBMANDIBULAR AND SUBLINGUAL GLANDS
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IX- GLOSSOPHARYNGEAL
1.
PAROTID GLAND
X- VAGUS
1. THORACIC AND ABDOMINAL VISCERA
SPECIAL SENSES
VISION
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2.
3.
4.
5.
ORGAN- EYE
1/6 TH SEEN OUTSIDE REST
INSIDE---ORBITAL CAVITY(
FAT)
ACCESSORY STRUCTURES
Eyebrows
EYELIDS
CONJUNCTIVA
LACRIMAL APPARATUS
EXTRINSIC MUSCLES
EXTERNAL ANATOMY
CLINICAL CONDITIONS
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CHALAZION-INFECTION OF THE
TARSAL GALNDS( MEBOMIAN )
STY- INFECTION OF THE CIALIARY
GLANDS
CONJUNCTIVITIS- ( PINK EYE) --INFLAMMANTION OF ?
LACRIMAL APPARATUS
EXTRINSIC MUSCLES OF THE
EYE
EXTRINSIC MUSCLES
ANATOMY OF THE EYEBALL
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FUNCTIONS
A) PROTECTS AND SUPPORTS THE
DELICATE PHOTORECEPTOR CELLS
B)GATHERS,FOCUSES AND
PROCESSES LIGHT INTO PRECISE
IMAGES
PARTS
1.
ANTERIOR POLE
2.
POSTERIOR POLE
3.
TUNICS( EXTERNAL WALL)
4.
HUMORS( FLUID ) INSIDE
5.
LENS
TUNICS
FIBROUS
SCLERA
VASCULAR
SENSORY
CHORIOD
CORNEA
RETINA
CILIARY BODY
IRIS
• FIBROUS TUNIC(OUTERMOST)
• - DENSE CONNECTIVE TISSUE( PROTECTION, MUSCLES
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INSERTED)
POSTERIOR 5/6TH ( SCLERA) –WHITE OF THE EYE
ANTERIOR 1/6TH TRANSPARENT –CORNEA( AVASCULAR)
LIMBUS
SCLERAL VENOUS SINUS( DRAINS AQUEOUS HUMOR)
• VASCULAR TUNIC( MIDDLE)
• CHOROID, CILIARY BODT AND IRIS
• CHOROID--- VASCULAR , PIGMENTED( LIGHT IS NOT
SCATTERED)
• CILIARY BODY---CILIARY MUSCLE----CIRIARY PROCESSES
• IRIS---( COLOR OF THE EYE)----CENTRAL OPENING ---PUPIL
INTERNAL ANATOMY
SAGITTAL SECTION
INTERNAL ANATOMY
RETINA
LIGHT
PHOTORECEPTOR
BIPOLAR CELLS
• SENSORY(
• INNERMOST)
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GANGLION CELLS
OPTIC NERVE
BRAIN
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RETINA( MOST IMPORTANT)
OUTER ---PIGMENTED(
PREVENTS LIGHT
SCATTERING)
INNER---NEURAL ( LIGHT
SENSITIVE PHOTORECEPTOR
CELLS, BIPOLAR AND GANLION
CELLS
PHOTORECTORS----RODS/
CONES
OPTIC NERVE
EAR
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SOUND WAVES
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EAR DRUM
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OSSICLES
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INNER EAR
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RECEPTOR ORGAN FOR
HEARING AND EQUILIBRIUM
OUTER/ MIDDLE EAR-----HEARING
INNER EAR---HEARING/EQUILIBRIUM
OUTER EAR
PINNA---AURICLE( ELASTIC
CARTILGE,EXCEPT—LOBULE)
EXT ACOUSTIC MEATUS—
2.5MM TUBE---AURICLE----EAR
DRUM( EAR WAX)
EAR DRUM---TYMPANIC
MEMBRANE---BOUNDARY
BETWEEN OUTER AND MIDDLE
EAR
MIDDLE EAR
• ALSO CALLED TYMPANIC CAVITY
• AIR FILLED / INSIDE THE PETROUS TEMPORAL
• LATERAL BOUNDARY—TYMPANIC MEMBRANE, MEDIAL
BOUNDARY—BONE SEPERATING IT FROM THE MIDDLE EAR
SUPERIOR BOUNDARY-PETROUS TEMPORAL
POSTERIOR WALL—MASTOIOID ANTRUM
INFERIOR BOUNDARY----BONE/IJV
ANTERIOR BOUNDARY-BEHIND ICA
• MEDIAL WALL---OVAL AND ROUND WINDOW
• PHARYNGOTYMPANIC TUBE CONNECTS IT TO THE
NASOPHARYNX
• OSSICLE ARE PRESENT
• 2 MUSCLES- STAPEDIUS/ TENSOR TYMPANI
INNER EAR
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ALSO CALLED LABYRINTH(
MAZE LIKE)
BONY
LABYRINTH/MEMBRANOUS
LABYRINTH
BONY---PETROUS TEMPORAL---SEMICIRCULAR CANALS,
VESTIBULE AND COCHLEA---PERILYMPH
MEMBRANOUS –SMICIRCULAR
DUCTS,UTRICLE, SACCULE,
COCHLEAR DUCT
SEMICIRCULAR CANALS
VESTIBULE
UTRICLE/SACCULE
EQUILIBRIUM
SEMICIRCULAR DUCTS
HEARING
COCHLEA
COCHLEAR DUCT