Spinal Cord And CSF Flashcards
1) Choroid plexus
1) tela choroidea - ependyma enclosing tuft of capillary —⟩ joint together to form Choroid plexus.
— Lateral and 3rd ventricle = Anterior Choroid artery ( branch of Internal carotid) and posterior Choroid artery (branch of posterior cerebral artery)
— 4th ventricle = Posterior Inferior cerebellar artery and Anterior Inferior cerebellar artery. PICA > AICA.
CSF
1) production
2) Rate
3) Circulation
1) Choroid plexus, ependyma cell lining ventricle, brain substance.
2) 500 - 600ml/day > 600-700 ml/day
3) Lateral Ventricle ———⟩ foramen Monro ———⟩ 3rd ventricle ———⟩ cerebral aqueduct of sylvius ———⟩ 4th ventricle ———⟩central canal of spinal cord and subarachnoid space.
4th Ventricle ———⟩ Foramen of magendie (medial aperture) ———⟩ cisterna magna (cerebello medullary system) ———⟩arachnoid villi ———⟩ Dural venous sinus (superior sagittal sinus) be CSF pressure > Blood pressure.
4th ventricle ———⟩ foramen of luschka (2 lateral aperture) –——⟩ cerebellopontine cistern ———⟩ arachnoid villi.
Arachnoid villi - act as a valve, rate of absorption is controlled by CSF pressure.
1) Congenital Aqueduct stenosis
2) Dandy Walker Syndrome
1) stenosis of cerebral aqueduct of sylvius.
- 3rd ventricle dilates.
- MCC of congenital hydrocephalus.
2) atrasia of foramen of luschka and magendie.
- due to cyst in posterior cranial fossa
Dilatation of 4th ventricle
1) epidural
2) Subdural
3) pacchionian bodies
4) Dural Fold
5) plaque jaune
1) Middle cerebral artery pass in it. Pterion - junction of temporal, parital, frontal, greater wing of sphenoid. Poin of Anterior branch of middle cerebral artery. # pterion - epidural haemorrhage - idli shape, biconvex, arterial Lucid interval - epidural haemorrhage > subdural.
2) subdural
- contain bridging veins = drain cerebral vein into Dural venous sinus (space b/w two layer of Dural matter contain blood.)
Subdural haemorrhage - c shape, cresentric, venous hemorrhage.
3) hypertrophy arachnoid villi (arachnoid granulation). - focal pouches of arachnoid mater and subarachnoid space protruding through the wall of Dural venous sinuses.
4) Falx Cerebri, tentorium Cerebri.
5) shrunken, yellow brown, cystic lesions in the gyri and subarachnoid space associated with head injury.
Cistern
1) peduncular/ basal/ interpeduncular - at base of skull, circle of will
2) cisterna magna - cerebellomedullary, have vertebral artery, PICA, 9,10,11,12 CN
3) pontine - ventral surface of pons, basilar artery
4) quadrigeminal - ambient, between corpus callosum and cerebellum, contain great cerebral vein of gallan
5) sylvian - lateral sulcus, middle cerebral artery, superficial and deep middle cerebral vein.
Lateral ventricle
1) part
2) Relation
1) Anterior horn - frontal
Posterior horn - occipital
Inferior horn - temporal
Body - parital
2) A) Anterior horn - medial = septum pellucidum - Anterior = genu and rostrum of corpus callosum - roof = body of corpus callosum - floor = head of caudate nucleus.
B) Body (interventricular foramen to splenium of corpus callosum
- Roof - body of corpus callosum
- floor - body of caudate nucleus, fornix of thalamus
- medial wall - septum pellucidum
C) Posterior horn
- roof and lateral wall - tapetum (fibers from body and splenium of corpus callosum
- floor - forceps major
And Anterior part of calcarine sulcus (calcar avis is white matter of calcarine sulcus) both forms two elevation on posterior horn.
D) Inferior horn
- Roof - tail of caudate nucleus
- floor - hippocampus
3rd ventricle
Lateral - Thalamus and hypothalamus
Anterior - fornix (Anterior column), Anterior commissure, lamina terminalis
Posterior - penial gland, habenular, posterior commissure
Floor - optic chiasma, infandibulum, pitutary gland, Tuber cinereum, mammary body, posterior perforated substance, tegmentum membrane.
4th ventricle
Roof - superior medullary velum (white matter) , Inferior medullary velum ( ventricular ependyma and pia mater of tela choroidea, pierce by magandie in the mid line)
Floor - lower part of pons, upper part of medulla
Between medulla and pons - striae medullaris
Center of floor - (medial to lateral) median sulcus ———⟩ medial eminence and facial colliculus ———⟩ sulcus limitans ———⟩ vestibular area ———⟩ superior cerebellar penduncles.
Upper part of sulcus limitans - locus coernuleus / substantia ferruginea ( pigmented gray matter structure)
Medulla - (above to downward and medial to lateral) - hypoglossal triangle ———⟩ Inferior fovea ———⟩ vagal triangle ——⟩ area postrema ——⟩ gracile tubercle ——⟩ cuneate tubercle ———⟩ Inferior cerebellar penduncles.
Lateral - cerebellar penduncles
T shaped choroid plexus is formed from the tela choroidea and two layer of pia matter.
Circumventricular organ
Penial gland Organum vasculosum of Lamina terminalis Median eminence (hypothalamus) Pars nervosa (pitutary gland) Area postrema (in floor of 4th ventricle) Sub commissural organ Sur fornical organ
No blood brain barrier.
1) Facial colliculus
2) Tumor in pineal gland
3) Brain sand
Axon of 7th CN covering 6th CN nucleus.
Injury - affect on 7>6
2) parinaud syndrome - compression on dorsal part of brain.
3) A/K/A corpora arenacea - calcareous deposit in the astrocytes of pineal gland.
1) Size of spinal cord
2) meningis - denticulatum
3) spinal enlargement
Adult - upto lower border of L1
Child - upto upper border of L3
Become like adult after 2 years
2) pia meter is upto L1
Filum terminale - pia from L1 to 1st coccyx.
- internum - pia from L1 to S2, inside arachnoid matter. 15cm
- externum - S2 to coccyx.5cm
Denticulatum - tooth like projection of pia matter. Serrated appearance. Between ventral and dorsal root. On each side 21 projection. Connect pia to Dura Last projection at T12- L1 Imp for sx.
— Arachnoid - upto lower border of S2
— Dura (single layer) - coverages at level of S2 and continue upto coccyx.
3) cervical - C4 to T2
Lumbar - L2 to S3
Spinal nerves and vertebrae
31 pairs of spinal nerve
33 vertebrae
Spinal nerves. Vertebrae Upper cervical C2. - C2 Lower cervical C6. C5 Upper thorasic T5 T3 Lower thorasic T10. T7
1) Conus medullaris
2) cauda equina
1) Taper end of spinal cord - sacral and coccygeal nerve arise from here
Syndrome
- CNS injury
- motor involvement is less
- Ankle jerk S1, S2 - Absent
- knee jerk L3, L4 - present
- perianal anesthesia
- Bladder involvement
» Detrusor muscle via pelvic splanchnic nerve - S2, S3, S4 ( nervi erigentes)
» Spincter urethra via pudendal nerve - S2, S3,S4
Urinary retention and incontinence.
- Importance - bulbocavernosus and ischiocavernosus muscle (S2, S3, S4 - pudendal nerve)
2) Bunch of spinal nerve of L2 to coccyx.
- PNS injury
- motor involvement is more.
- Knee and ankle jerk both absent
- perianal anesthesia + sensory loss over public region
- bladder and importance - very late.
Nucleus of spinal cord
1) Anterior horn
- lateral = innervates limb muscle
- medial = axial muscle
- intermediate = phrenic nereve (C3 to C5) and spinal accesory nerve (C1 to C5)
2) posterior horn nucleus :
- substatia gelatinosa - it continues as spinal nucleus of trigeminal. It is a nucleus of spinothalamic track.
- nucleus proprius - few fibres of dorsal column. Rely reflex.
- nucleus dorsalis or Clarke’s column - spinocerebellar track.
- Visceral afferent
3) lateral horn nucleus
- medial - parasympathetic (S2 - S4)
- lateral - sympathetic (T1 - L2)
Sympathetic chain ganglion
Lateral horn —⟩ preganglionic fibers —⟩ ventral root —⟩ white Rami communicant (myelinated, Ach., —⟩ sympathetic ganglion — ⟩ post ganglion fibers —⟩ grey Rami communicant (noradrenaline, medial to white rami) —⟩ spinal nerve.
While in somatic system fibers directly goes to spinal nerve to target organ.
