Anatomi Sistem Saraf Pusat
SISTEM SARAF PUSAT dan TEPI(mencakup komponen fungsional:
motorik, sensibel/sensorik, otonom, luhur)
Komponen otak Fungsi otak
Korteks serebrum Persepsi sensorik
Kontrol gerakan volunter
Bahasa
Sifat pribadi
Proses mental canggih (berpikir, mengingat, membuat keputusan)
Nukleus basal Inhibisi tonus otot
Koordinasi gerakan yang lambat dan menetap
Penekanan pola gerakan yang tidak berguna
Talamus Stasiun pemancar untuk semua masukan sinaps
Kesadaran kasar terhadap sensasi
Beberapa tingkat kesadaran
Berperan dalam kontrol motorik
Komponen otak Fungsi otak
Hipotalamus Mengatur fungsi homeostasis (suhu, haus, urin, asupan makanan)
Penghubung penting antara sistem saraf dengan endokrin
Emosi dan pola perilaku dasar
Serebelum Memelihara keseimbangan
Peningkatan tonus otot
Koordinasi dan perencanaan aktivitas otot volunter yang terlatih
Batang otak Asal dari sebagian besar saraf kranialis perifer
Pusat pengaturan kardiovaskuler, respirasi, dan pencernaan
Pengaturan refleks otot yang terlibat dalam keseimbangan & postur
Penerimaan dan integrasi semua masukan sinaps dari korda spinalis
Pusat tidur
Lobus Otak • Lobus Oksipitalis
– Posterior penglihatan• Lobus Temporalis
– Lateral sensasi suara• Lobus Parietalis
– Di puncak kepala di belakang sulkus sentralis menerima sensasi sentuhan, tekanan, panas, dingin, nyeri, posisi tubuh
• Lobus Frontalis– Di korteks bagian depan mengatur aktivitas motorik
volunter, kemampuan berbicara, dan elaborasi pikiran
Bagian-bagian otak:• A. Berdasarkan letak:
– Prosencephalon, terdiri dari:a. Telencephalonb. Diencephalon
– Mesencephalon– Rombencephalon, terdiri dari:
a. Cerebellumb. Ponsc. Medulla oblongata
• B. Berdasarkan fungsi1. Cerebrum, terbagi menjadi:
a. Hemisfer cerebri dextrab. Hemisfer cerebri sinistraKeduanya dipisahkan oleh fisura longitudinalis
– Struktur cerebrum terdiri dari sulcus dan gyrusLobus pada cerebrum:a. Lobus frontalis → untuk pergerakanb. Lobus parietalis → untuk sensori (rasa/raba)c. Lobus temporalis → untuk pendengarand. Lobus okcipitalis → untuk penglihatan
• 2. Cerebellum, terbagi menjadi:a. Hemisfer cerebri dextrab. Hemisfer cerebri sinistraKeduanya dipisahkan oleh fisura formis
• 3. Truncus cerebri– Medulla spinalis terbagi menjadi:
a. Cervical → 8 Cb. Torakal → 12 Tc. Lumbal → 5 Ld. Sacral → 5 Se. Koksigeal → 3 pasang
Lapisan Pelindung
SSP
Sawar Darah Otak
Korteks Serebrum• Terbagi menjadi hemisfer kanan dan kiri• Terdiri dr substansia alba & grisea• Fungsi :
– Persepsi sensorik– Kontrol gerakan volunter– Bahasa– Sifat pribadi– Berpikir, mengingat,
membuat keputusan, kreativitas, dan kesadaran diri
Daerah Fungsional Korteks Serebrum
Kemampuan Berbahasa
VASKULARISASI OTAK
Arteries to Brain Schema
Vaskularisasi Otak • Arteri karotis interna regio sentral dan lateral hemisfer.• Arteri serebri anterior korteks orbitalis, frontalis, parietalis
bagian tengah, korpus kalosum dan nukleus kaudatus.• Arteri serebri media korteks orbitalis, lobus frontalis,
parietalis dan temporalis. • Arteri vertebralis batang otak dan medula spinalis atas. • Arteri basilaris pons. • Arteri serebri posterior lobus temporalis, oksipitalis, sebagian
kapsula interna, talamus, hipokampus, korpus genikulatum dan mamilaria, pleksus koroid dan batang otak bagian atas.
• Arteri koroidal pleksus koroid temporal lateral ventrikel.
Vaskularisasi otak - arteri
Vaskularisasi otak - vena
Superior sagittal sinus laid open after remova of the skull cap. The chordæ Willisii are clearly seen. The venous lacunæ are also well shown; from two of them probes are passed into the superior sagittal sinus
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Middle Cerebral Artery
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Anterior Cerebral Artery
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Anterior Cerebral Artery
Middle Cerebral Artery
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Posterior Cerebral Artery
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Posterior Cerebral Artery
hartono prabowo 43
BasilarArtery
Vertebral Artery
PosteriorCerebralArtery
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•
•
CCA
ICA
ACA
MCA
PCA
VA
BA
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MCA
ACA
PCA
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ACA
PCA
MCA
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ACA
MCA
PCA
hartono prabowo 48
Cerebral Venous System
Nervus Kranial
Cranial Nerves
• Terdapat 12 pasang nervus kranialis
• Meninggalkan otak melalui foramen-foramen kranial
• Beberapa berupa motorik, sensorik atau berupa campuran
Cranial Nerve I: Olfactory
Berasal dari epitel olfaktorius, melalui celah cribriform oleh os ethmoid, serabut saraf menjalar menuju korteks
Berupa kemoreseptor penciuman
CN I. Olfactory – four respects1. The somas of the primary
afferent neurons occupy a surface of epithelium.
2. The axons of the primary afferents enter the cerebral cortex directly.
3. The primary afferent neurons undergo continuous turnover, being replaced from basal stem cells.
4. The pathway to the highest cortical centers (in the frontal lobe) is entirely ipsilateral.
Olfactory
Unilateral Anosmia
Bilateral Anosmia
ANOSMIA
Head Trauma
Frontal Meningioma
Especially with leakage
of cerebrospinal
fluid
Cranial Nerve II: Optic
Arises from the retina. Optic nerves pass through the optic canals and converge at the optic chiasm. They continue to the thalamus where they synapse and the optic radiation fibers run to the visual cortexCarries afferent impulses for vision (Sensory) Symptoms of dysfunction: loss of vision
Visual Pathway
Retina
N. II
OpticalChiasma
Optical Tract
CGL
Opt. Radiation
Primary Visual Cortex
Lesions of the visual pathwaysLesions Field defects
Partial CN. II. Ipsilateral scotoma.
Complete CN. II.
Blindness in that eye.
Optic chiasm. Bitemporal hemianopia
Optic tract. Homonymous hemianopia.
Meyers loop Homonymous upper quadrant anopia.
Optic radiation Homonymous hemianopia.
Visual cortex Homonymous hemianopia.
Bilateral macular cortex
Bilateral sentral scotomas
CN. III (Oculomotor) , CN. IV (Trochlear) & CN. VI (Abducen)
• Motor nerves that innervate muscles of eye and orbit
• Leave cranial cavity by passing through superior orbital fissure to enter orbit
• Supply total of 9 muscles of the eye that include 6 skeletal muscles arising from the walls of the orbit and attaching to the eye, 2 smooth muscles within eye and 1 skeletal muscle of upper eyelid
Function of CN III, IV, VIRL6 (SO4)3
Cranial Nerve III: Oculomotor
Fibers extend from the ventral midbrain, pass through the superior orbital fissure, and go to the extrinsic eye muscles (4 of 6). Functions in raising the eyelid, directing the eyeball, constricting the iris, and controlling lens shape. (Parasympathetic cell bodies are in the ciliary ganglia)
CN. III: Oculomotor
Major functions: innervates all extraocular muscles - except superior oblique and lateral rectus – and striated muscles of eyelid
Motor: eye movements – elevation (superior rectus when the eye is abducted and inferior oblique when adducted), depression (inferior rectus when eye is abducted), adduction and elevates upper eyelid
Parasympathetic: pupillary constriction in response to light; increases convexity of lens for near vision
Symptoms of dysfunction: double vision, drooping eyelid, deviation of eye outward, uneven dilation of pupils
CN. IV: Trochlear CN. VI: Abducens
• Motor• Innervates superior
oblique muscle• Depresses the
adducted eye• Symptoms of
dysfunction: double vision
• Motor• Innervates lateral
rectus muscle• Major function in
eye movement – abduction of eye
• Symptoms of dysfunction: double vision and inward deviation of eye
Cranial Nerve IV: Trochlear
Fibers emerge from the dorsal midbrain and enter the orbits via the superior orbital fissures; innervate the superior oblique musclePrimarily a motor nerve that directs the eyeball
Cranial Nerve VI: Abducens
Fibers leave the inferior pons and enter the orbit via the superior orbital fissurePrimarily a motor nerve innervating the lateral rectus muscle
Complete left III Nerve paralysis
Complete left VI nerve paralysis
Weber Syndrome
Pyramidal tract - contralateral UMN syndrome at the body and lower face (contralateral hemiparesis)
Oculomotor Nerve - ipsilateral ocular palsy - external strabismus - mydriasis - loss of accommodation - normal consensual light reflex
CN. V: Trigeminal
• Mixed motor and sensory• Has small motor root and large
sensory root; extends from brain stem to sensory ganglion (trigeminal ganglion) found in apex of petrous temporal bone
• Nerve divides into 3 branches beyond ganglion: V1(Opthalmic), V2 (Maxillary) and V3 (Mandibular)
• Sensory fibers enter each of divisions, motor fibers only enter V3 (only one mixed)
CN. V: Trigeminal
• V1 enters orbit through superior orbit fissure
• V2 enters pterygopalatine fossa through foramen rotundum
• V3 exits through foramen ovale to reach infratemporal fossa
• Major functions: -V1 – innervate structures of the orbit,
nose and forehead and scalp back to vertex of skull
-V2 – provide sensation from the skin over the cheek and to upper portion of oral cavity
CN. V: Trigeminal
- V3 – supplies sensation from the skin over the jaw , the area over the ear and the lower part of the oral cavity, including tongue (supplies muscles of mastication)
Symptoms of dysfunction: numbness in face, weakness and wasting of jaw muscles, brief attacks of severe pain, asymmetric chewing
Cranial Nerve V: Trigeminal
Trigeminal Neuralgia(tic douloureux)
- excruciating episodic pain in the area supplied by trigeminal nerve, especially second and third division- trigger point- intense pain makes the patient grimace (tic)- antiepileptic drug (phenytoin, carbamazepine) is effective- surgical treatment
Cranial Nerve VII: Facial
Fibers leave the pons, travel through the internal acoustic meatus, and emerge through the stylomastoid foramen to the lateral aspect of the faceMixed nerve with five major branchesMotor functions include facial expression, and the transmittal of autonomic impulses to lacrimal and salivary glandsSensory function is taste from the anterior two-thirds of the tongue
CN. VII: Facial
• Also parasympathetic and preganglion fibers
• Leaves cranial cavity by passing through internal auditory meatus where sensory ganglion is located; then runs in a bony facial canal in the temporal bone and exits the base of the skull through stylomastoid foramen; divides into terminal branches on face
VII. Facial Nerve
1. Facial Motor Nucleus
2. Superior Salivatory
Nucleus
3. Nucleus Tractus Solitarius
4. Spinal Tract Nucleus of V
VI. Abducens Nerve 5. Abducens Nucleus
Cranial Nerve VII: Facial
CN. VII: Facial
• Major functions: sensory – supply taste buds in anterior two-thirds of
tongue motor – innervates muscles of facial expression
(smiling, frowning, whistling)• Parasympathetic – innervates salivary glands except
parotid, as well as lacrimal glands and cerebral vasculature
• Symptoms of dysfunction: facial paralysis, loss of taste over anterior two-thirds of tongue
Right facial paralysis
Facial Palsy (Bell’s Palsy)
Central TypeFacial Palsy
Upper MotorNeuron
Syndromefacial motor nucleus neuronssupplying forehead muscle
Bilateral Corticobulbar Tract
Facial Palsy(Bell’s Palsy)
Lower MotorNeuron
SyndromeTriple W Sign - Wrinkle, Wink, Whistle
Cranial Nerve VIII: Vestibulocochlear
Fibers arise from the hearing and equilibrium apparatus of the inner ear, pass through the internal acoustic meatus, and enter the brainstem at the pons-medulla border. Two divisions – vestibular (balance) and cochlear (hearing)Functions are solely sensory – equilibrium and hearing
CN. VIII: Vestibulocochlear
• Sensory• Two components: cochlear and vestibular• Leaves cranial cavity by entering internal auditory
meatus; ends in specialized receptors of the inner ear located in the petrous temporal lobe
• Major functions: vestibular nerve conveys information regarding changes in position and movements of head needed to maintain equilibrium; cochlear aids in hearing
• Symptoms of dysfunction: deafness, feeling of distortion in space, dysequilibrium
CN. IX: Glossopharyngeal
• Mixed, with large sensory and small motor components, also parasympathetic and preganglion fibers
• Leaves cranial cavity by passing through jugular foramen in company of nerves X & XI to reach lateral aspect of pharynx
• Major functions: Sensory – supplies mucosa of posterior tongue and pharynx
including tonsillar area, so branches convey sensation and taste; provide sensory supply to specialized receptors in carotid body and sinus for reflex regulation of of blood pressure and respiration
CN. IX: Glossopharyngeal
• Motor – supplied one muscle of pharynx, the stylopharyngus; aids in swallowing
• Parasympathetic – innervates parotid gland; essential for secretion of saliva
• Symptoms of dysfunction: spasms of pain in posterior pharynx, maybe in fall of blood pressure
CN. X: Vagus
• Mixed and has additional large parasympathetic portion
• Leaves cranial cavity by passing through jugular foramen, along with IX & XI to reach lateral aspect of pharynx and larynx
• Major functions: Motor – supplies skeletal muscles of
pharynx, larynx and soft plate (important in swallowing)
Sensory – mediates sensation from posterior pharynx, visceral sensation from pharynx, larynx, thoracic and abdominal organs
CN. X: Vagus
Parasympathetic – innervates smooth muscle and glands of gastrointestinal, pulmonary, cardiovascular systems in neck, thorax and abdomen
• Symptoms of dysfunction: hoarseness, poor swallowing, loss of gag reflex
Cranial Nerve X: Vagus
Fibers emerge from the medulla via the jugular foramen - a mixed nerveMost motor fibers are parasympathetic fibers to the heart, lungs, and visceral organsIts sensory function is in taste
The Human Cranial Nerves Parasympathetic Ganglia
General Visceral Efferent Nuclei (GVE)
Dorsal Motor Nucleus of Vagus X
Inferior Salivatory Nucleus IX
Superior Salivatory Nucleus VII
Edinger-Westphal Nucleus III
Cranial Nerve XI: AccessoryFormed from a cranial root emerging from the medulla and a spinal root arising from the superior region of the spinal cord. The spinal root passes upward into the cranium via the foramen magnum. The accessory nerve leaves the cranium via the jugular foramenPrimarily a motor nerve -supplies fibers to the larynx, pharynx, soft palate, trapezius, and sternocleidomastoid
CN. XI: Spinal Accessory
• Motor• Arises from upper cervical spinal cord
and enters cranial cavity through foramen magnum; leaves via jugular foramen
• Major function: innervates trapezius and sternocleidomastoid muscles
• Symptoms of dysfunction: inability to shrug, wasting of neck with weakened rotation
CN. XII: Hypoglossal• Motor• Leaves cranial cavity through hypoglossal (anterior condylar)
canal• Major function: innervates muscles of tongue• Symptoms of dysfunction: wasting of tongue with deviation to
side of lesion on protrusion
Wallenberg SyndromeSpinothalamic tract - contralateral loss of pain and temperature sensation at the body
Spinal tract of trigeminal nerve - ipsilateral loss of pain and temperature sensation at the face
Nucleus ambiguus - dysphageia, dysarthria, hoarseness
Descending autonomic pathway - Horner’s syndrome (miosis, ptosis, anhydrosis)
•Sensory:
•I Olfactory •II Optic •VIII Vestibulocochlear
•Mixed Sensory & Motor:
•V Trigeminal •VII Facial •IX Glossopharyngeal •X Vagus
•Motor:
•III Oculomotor •IV Trochlear •VI Abducens •XI Accessory •XII Hypoglossal
•Parasympathetic:
•III Oculomotor •VII Facial •IX Glossopharyngeal •X Vagus
•Key: Blue - sensory Green - motor Red - mixed
Summary of cranial nerve
Summary of Function of Cranial Nerves
Nerve & Component fibres
S = Sensory M = MotorP = Parasympathetic
Function Structures innervated
I Olfactory S smell olfactory bulbsII Optic S vision retinaIII Oculomoto
r Meyeball movement
4 eyeball muscles & 1 eyelid muscle
lens accomodation
III Oculomotor P pupil
constriction
IV Trochlear M eyeball movement
superior oblique muscles
V Trigeminal S sensations face, scalp, teeth, lips, eyeballs, nose & throat lining
general sensory from tongue
anterior two thirds of tongue
proprioception muscles of masticationV Trigeminal M chewing muscles of mastication
Summary of cranial nerve
Summary of cranial nerve
VI Abducens M eyeball movement
lateral rectus muscle
VII Facial S taste anterior two thirds of tongue
proprioception
face & scalp
VII Facial M facial expressions
muscles of the face
VII Facial P salivation and lacrimation
salivary and lacrimal glands via submandibular and pterygopalatine gamglia
VIII Vestibulocochlear
S balance vestibular apparatus of internal ear
hearing cochlear of internal ear
Nerve & Component fibres
S = Sensory M = MotorP = Parasympathetic
Function Structures innervated
Summary of cranial nerve
X Vagus S chemoreceptors blood oxygen concentration, aortic bodies
pain receptors respiratory & digestive tractssensations external ear, larynx &
pharynxtaste tongue
X Vagus M heart rate & stroke volume
pacemaker & ventricular muscles
peristalsis smooth muscles of digestive tract
air flow smooth muscles in bronchial tubes
speech & swallowing
muscles of larynx & pharynx
XI Spinal Accessory
M head rotation trapezius & sternocleidomastoid muscles
XII Hypoglossal
M speech & swallowing
tongue & throat muscles
Nerve & Component fibres
S = Sensory M = MotorP = Parasympathetic
Function Structures innervated
CRANIAL NERVES
GSA SpSA VA GSE SpVE GVEV VIII
a. N. Cochl.
b. N. Vest.
Sp.VA I, V, VII,
IX, X
III, IV, VI, XII
V, VII, IX, X, XI
III, VII, IX, X
GVAIX, X
No. Disease / Symptoms
Lesion of Oculomotor Nerve
III~Droopy eyelid; pupil dilation - unresponsive to light & accommodation; inability to move eyeball up, down and inwards.
Lesion of Abducens Nerve
VI ~Inability to move eyeball outwards.
Lesion of Trigeminal Nerve
V
~Herpes zoster infection of sensory roots of Trigeminal Nerve leads to pain & eruption of vesicles of dermatome supplied by opthalmic, maxillary & mandibular branches of trigeminal nerve.~Syringobulbia leads to selective loss of pain & temperature sensibility in the face.
Lesion of Facial Nerve VII
~Bell's palsy - pain around ear; paralysis of the facial muscles; failure to close eye; absent corneal reflex; hyperacusis on affected side; loss of sensation in anterior two thirds of tongue
Lesion of Vestibulocochlear Nerve
VIII~Acoustic neuroma - dizziness & deafness; ataxia & paralysis of the cranial nerves (especially V - VII) and limbs
The Human Cranial Nerves Diseases of the Cranial Nerves
Cranial nerve
Nucleus name Nucleus location Function Symptom/sign of damage
Olfactory (CNI)
Anterior olfactory
Olfactory tract
Smell Anosmia
Optic (CNII)
Lateral geniculate nucleus
Thalamus Vision Blindness, hemianopsia
Oculomotor (CNIII)
OculomotorEdinger Westphal
MidbrainMidbrain
Eye movement(elevation, adduction)
Eye deviates down & outLoss of pupillary/accommodation reflexes
Trochlear (CNIV)
Trochlear Midbrain Eye movement(depression of adducted eye)
Diplopia, lateral deviation of eye
Trigeminal (CNV)
PrincipalSpinalMesencephalicMotor
PonsMedullaPons/midbrainPons
Facial sensationMastication
Facial aneasthesia Loss of pain sensationInsignificantWeakness/loss of mastication
CRANIAL NERVES: SUMMARY TABLE.
CRANIAL NERVES: SUMMARY TABLE.
Abducent (CNVI)
Abducent Pons Eye movement (Abduction)
Medial eye deviation
Facial (CNVII)
MotorSolitarySuperior salivatory
PonsPonsPons
Facial expresssion TasteSalivation, lacrimation
Paralysis of facial nerve muscles (+ hyperacuisis)Loss of taste (anterior 2/3rds of tongue)Dry mouth, loss of lacrimation
Vestibulocochlear (CN VIII)
VestibularCochlear
MedullaMedulla
BalanceHearing
Vertigo, dysequilibrium, nystagmusHearing
Glossopharyngeal (CN IX)
Nucleus ambiguusInferior salivatorySolitary
MedullaMedullaMedulla
TasteSalivationInnervation of pharynx
Loss of taste (posterior 1/3rd of tongue)InsignificantLoss of gag reflex
Cranial nerve Nucleus name Nucleus location
Function Symptom/sign of damage
Vagus (X) Nucleus ambiguusDorsal motor vagal Solitary
MedullaMedullaMedulla
Swallowing & talkingCardiac, GI tract, respirationTaste
Dysphagia & hoarseness of voiceInsignificantLoss of cough reflex (larynx/pharynx), loss of taste (hard palate)
Cranial Accessory (XI)Spinal accessory
Nucleus ambiguusSpinal accessory
MedullaCervical cord
Pharynx/larynx musclesNeck & shoulder movement
InsignificantHead turning/shoulder shrugging weakness
Hypoglossal (XII)
Hypoglossal
Medulla Tongue movement
Atrophy of tongue muscles, deviation on protrusion, fasciculaations
CRANIAL NERVES: SUMMARY TABLE.
Cranial nerve
Nucleus name
Nucleus location
Function Symptom/sign of damage