Term
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Definition
three C.T. membranes that cover spinal cord and brain.
consists of: pia mater and arachnoid and dura mater (pachymeninx)
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Term
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Definition
- delicate
- highly vascular
- covers surface of brain and spinal cord
- connected to arachnoid by trabeculae
forms:
denticulate ligaments
filum terminale |
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Term
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Definition
two lateral flatteend bands of pial tissue
adheres with dura mater w/ 21 attachments |
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Term
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Definition
nonneural band of tissue
condensation of pia mater
extends from conus medullaris to end of dural sac and fuses with it |
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Term
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Definition
- delicate
- non-vascular C.T.
- b/w dura and pia
forms:
a. arachnoid granulations/arachnoid villi
b. subarachnoid space |
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Term
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Definition
- outer layer of meninges
- dense C.T.
forms:
a. falx cerebri
b. tentorium cerebelli
c. diaphragma sellae
d. dural sinuses |
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Term
Supratentorial dura innervation |
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Definition
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Term
Posterior fossa innervation |
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Definition
vagal nerve
upper spinal nerve |
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Term
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Definition
- b/w cerebral hemispheres in long. cerebral fissures
- contains: superior and inferior sagittal sinuses b/w its two layers
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Term
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Definition
- separates: posterior cranial fossa from middle cranial fossa
- separates: temporal and occipital lobes from cerebellum and infratentorial brainstem
contains:
a. tentorial incisure |
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Term
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Definition
notch through which brainstem passes
present in tentorium cerebelli
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Term
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Definition
- roof of hypophyseal fossa
- contains: aperture through which hypophyseal stalk (infundibulum) passes
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Term
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Definition
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Term
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Definition
- Spinal Epidural Space
- Cranial Epidural Space
- Subdural Space
- Subarachnoid Space
- Subarachnoid Cisterns
a. Cerebellopontine angle cistern
b. Cerebrellomedullary cistern (cisterna magna)
c. Ambient cistern
d. Superior cistern |
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Term
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Definition
- b/w dura and vertebral periosteum
- contains:
a. loose areolar tissure
b. venous plexuses
c. lymphatics
- injected w/ local anethetic to produce paravertebral nerve block
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Term
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Definition
- potential space b/w periosteal and meningeal layers of dura
- contains:
a. meningeal a. b. meningeal v. |
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Term
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Definition
a. space b/w dura and arachnoid
b. intracranially transmits superior cerebral v. to venous lacunae of superior sagittal sinus
c. lateration of these "bridging veins" → subdural hemorrhage (hematoma) |
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Term
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Definition
- b/w pia and arachnoid
- contains: CSF
- surrounds entire brain + spinal cord
- entends below conus medullaris → S2--lumbar cistern
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Term
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Definition
- dilations of subarachnoid space
- contains CSF
- named after structures over which they lie, i.e. pontine, chiasmatic, and interpeduncular cistersn
- 4 types:
a. cerebellopontine angle cistern
b. cerebellomedullary cistern (cisterna magna)
c. ambient cistern
d. superior cistern |
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Term
Cerebellopontine angle cistern |
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Definition
- receives CSF from 4th ventricle via lateral foramina of Luschka
- contains: facial nerve (CN VII) + vestibulocochlear n. (CN VIII)
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Term
Cerebellomedullary cistern (cisterna magna) |
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Definition
- in midline b/w cerebellum and medulla
- receives CSF from 4th ventricle via median formaen of Magendie
- tapped for CSF (suboccipital tap)
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Term
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Definition
- interconnects superior and interpenduncular cisterns
- contains: trochlear nerve (CN IV)
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Term
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Definition
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Term
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Definition
- benign
- slow-growing
- well-demarcated tumors
- arise from meningotheal arachnoid cells
- 20%--primary intracranial tumors
- 25%--spinal tumors
- most frequently found in: anterior cranial fossa (parasagittal 25%, convexity 20%, basal 40%)
- histologically characterized by: whorling pattern and calcified psammoma bodies
- enlarge slowly
- create cavity in adjacent brain
- occurence: adult (20-60 yrs)
- most often in women (60%)
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Term
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Definition
- lined by ependyma
- contain: choroid plexus, which produces CSF @ rate of 500 ml/day
- communicate w/ subarachnoid space via 3 foramina in 4th ventricle
- consists of: 4 fluid-filled communicating cavities w/in brain
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Term
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Definition
- two ventricles
- located w/in cerebral hemispheres
- communicate w/ 3rd ventricle via interventricular foramina of Monro
- consists of 5 parts:
a. frontal (anterior) horn
b. body
c. temporal (inferior) horn
d. occipital (posterior) horn
e. trigone (atrium) |
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Term
Frontal (anterior) horn--lateral ventricle |
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Definition
- w/in frontal lobe
- lateral walls are formed by head of caudate nucleus
- lacks choroid plexus
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Term
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Definition
- w/in medial portion of frontal and parietal lobes
- contains choroid plexus
- communicates via interventricular foramen of Monro w/ 3rd ventricle
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Term
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Definition
- w/in medial part of temporal lobe
- has choroid plexus
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Term
Occipital (posterior) horn |
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Definition
- w/in parietal and occipital lobe
- lacks choroid plexus
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Term
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Definition
- @ the junction of body, occipital horn, and temporal horn of lateral ventricle
- contains: glomus
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Term
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Definition
- found w/in trigone
- large tuft of choroid plexus
- calcified in adults
- visible on x-ray films and computed tomography (CT)
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Term
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Definition
- slitlike vertical midline cavity of diencephalon
- communicated w/ lateral ventricles via interventricular foramina of Monro + 4th ventricle via cerebral aqueduct
- contains: pair of choroid plexuses in its roof
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Term
Cerebral aqueduct (aqueduct of Sylvius) |
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Definition
- w/in midbrain
- connects 3rd ventricle w/ 4th ventricle
- lacks choroid plexus
- blockage → hydrocephalus (aqueductal stenosis)
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Term
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Definition
- b/w cerebellum and brainstem
- contains: pair of choroid plexus in caudal roof
- expresses CSF into subarachnoid space via two lateral foramina of Luschka and single medial foramen of Magendie
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Term
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Definition
- clear, colorless, acellular fluid
- found in: subarachnoid space + ventricles
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Term
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Definition
- produced by choroid plexus
- rate: 500 ml/day
- total CSF volume = 140 ml
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Term
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Definition
- supports and cushions CNS against concussive injury
- transports hormones + hormone-releasing factors
- removes metabolic waste products through absorption
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Term
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Definition
- site of greatest absorption
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Term
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Definition
- flows from ventricles via 3 foramina of 4th ventricle → subarachnoid space and over the convexity of hemisphere → superior sagittal sinus → venous circulation
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Term
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Definition
- no more than 5 lymphocytes/µl
- sterile--usually
- normal values
a. pH: 7.35
b. Specific gravity: 1.007
c. Glucose: 66% of plasma glucose
d. Total protein: < 45 mg/dl in lumbar cistern |
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Term
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Definition
- 80-180 mm of water (CSF) in lumbar subarachnoid space when pt is in a lateral recumbent (decubitus) position
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Term
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Definition
- dilation of cerebral ventricles
- caused by blockage of CSF pathways
- characterized by: excessive accumulation of CSF in cerebral ventricles or subarachnoid space
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Term
5 types of Hydrocephalus: |
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Definition
- noncommunicating hydrocephalus
- communicating
- normal-presure
- hydrocephalus ex vacuo
- pseudotumor cerebri (benign intracranial hypertension)
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Term
Noncommunicating hydrocephalus |
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Definition
- due to obstruction w/in ventricles
- i.e. congential aqueductal stenosis
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Term
Communicating Hydrocephalus |
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Definition
- due to blockage w/in subarachnoid space
- i.e. adhesions after meningitis
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Term
Normal-pressure hydrocephalus |
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Definition
- CSF is not absorbed by arachnoid villi
- secondary to post-traumatic meningeal hemorrhage
- clinically characterized by: triad of progressive dementia, ataxic gait, urinary incontinence (wacky, wobbly, and wet)
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Term
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Definition
- loss of cells in caudate nucleus
- i.e. Huntington disease
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Term
Pseudotumor cerebri (benign intracranial hypertension) |
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Definition
- increased resistance to CSF outlfow @ arachnoid villi
- characterized by:
a. papilledema w/o mass
b. elevated CSF pressure
c. deteriorating vision
- ventricles may be slit-like
- occurs in obese young women
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Term
Meningitis (pl. meningitides) |
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Definition
- inflammation of pia-arachnoid of brain, spinal cord or both
- types:
a. bacterial (pyogenic)
b. viral (lymphocytic)
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Term
Bacterial (pyogenic) meningitis |
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Definition
- common in children under 5 yrs (>70% of all cases)
- clinical characterization:
a. fever
b. headache
c. nuchal rigidity w/ kernig sign
- result in cranial n. palsies (CN III, IV, VI, VIII) and hydrocephalus
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Term
Common etiologic agents--bacterial meningitis |
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Definition
cause: group B streptococci (S. agalactiae) + E. coli
immunization against Haemophilus influenzae has significantly reduced this type of meningitis
- older infants and young children: 1 month- 9 yrs
frequent cause: S. pneumoniae + Neisseria meningitidis
cause: S. pneumoniae
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Term
CSF findings in bacterial meningitis |
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Definition
- numerous neutrophils
- decreased glucose level
- elevated protein level
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Term
Viral (lymphocytic) meningitis |
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Definition
- also known as: aspectic meningitis
- characterized by:
a. fever
b. headache
c. nuchal rigidity w/ Kernig sign
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Term
Virus causing viral meningitis: |
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Definition
- Mumps virus
- Enteric cytopathic human orphan (ECHO) viruses
- Coxsackie virus
- Epstein-Barr
- Herpes simplex virus (type 2)
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Term
CSF findings from viral meningitis: |
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Definition
- numerous lymphocytes
- normal glucose
- normal to slightly increased protein
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Term
3 froms of herniation in brain: |
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Definition
- transtentorial (uncal)
- transforminal (tonsillar)
- subfalcial
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Term
Transtentorial (uncal) herniation: |
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Definition
brain protrudes through tentorial incisure |
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Term
Transforaminal (tonsillar) herniation |
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Definition
brainstem and cerebellum protrudes through foramen magnum |
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Term
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Definition
herniation below falx cerebri |
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Term
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Definition
- chemosensitive zones
- monitor concentrations of circulating hormones in blood + CSF
- located in periphery of 3rd ventricle
- area prostrema--found in floor of 4th ventricle
- highly vascularized w/ fenestrated capillaries
- no blood-brain barrier (subcommissural organ--exception)
- includes:
a. organum vasculosum of lamina terminalis
b. median eminence of tuber cinereum
c. subfornical organ
d. subcommisural organ
e. pineal body
f. area postrema |
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Term
Organum Vasculosum of lamina terminalis |
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Definition
- vascular outlet for LH releasing hormone + somatostatin
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Term
Median eminence of tuber cinereum |
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Definition
- contains neurons that release and inhibit hormones into hypophyseal portal system
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Term
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Definition
- located on inferior surface of fornix @ level of interventircular foramen of Monro
- contains neurons that project to supraoptic nuclei + organum vasculosum
- central receptor site for angiotensin II
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Term
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Definition
- below the posterior commisure @ junction of 3rd vent + cerebral aqueduct
- composed of:
a. specialized ependymal cells
b. glial elements
c. capillary bed--contains nonfenestrated endothelial cells |
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Term
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Definition
a. calcareous granules--in brain sand/acervulus
i. seen on x-ray film + C.T.
ii. occur after 16 yrs of age
b. pinealocytes--epiphyseal cells
i. highly vascular w/ fenestrated capillaries
- derived from: diencephalon
- innervated solely via postganglionic fibers from superior cervical ganglion of ANS
- synthesizes: serotonin + melatonin.
- antigonadotrophic function
- pinealosomes--found in dorsal midbrain syndrome
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Term
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Definition
- two small subependymal oval areas on either side of 4th ventricle rostral to obex
- contains modified neurons + astrocytes-like cells surrounded by fenestrated capillaries
- chemoreceptor zone--triggers vomiting in response to circulating emetic substances
- role in food intake + cardiovascular regulation
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