Neuroanatomy - S&F II Flashcards
Infratentorial rumors
More common in infant/children
Supratentorial rumors
More common in adults
Dura Between the two hemispheres of cerebellum
Falx cerebelli
Supratentorial lesion can cause which vein to be compromised and impede venous outflow of blood from brain and or cause hemorrhage
Great cerebral vein of Galen
What veins converge at the confluence of sinuses?
- Superior sagittal
- Straight sinus
- Two transverse sinuses.
Two functions of venous sinus
- Venous drainage of blood from brain
2. Return of CSF to general systemic circulation.
Contents of subarachnoid space include
- Trabeculae
- CSF
- Blood vessels
Enlarged subarachinoid spaces where pools of CSF form
Cistern
CSF is found in three places
- Subarachinoid space
- Cisterns
- Ventricles (lateral and 4th)
Space in which vessels entering the brain lie in. It is made up of pia and subarachinoid space
Virchow-robin space
Meninges that covers brain cortex, internal ventricles and choroid plexus
Pia
Choroid plexus are made up of what type of cell?
Ependymal/ cuboidal epithelium cells
Normally CSF is clear and colorless with the following characteristics
Protein ~ 15-45mg/100ml
Glucose ~ 2/3rd blood glucose level; non-diabetic ~40-80mg/100ml
Cells 0-5 mononuclear lymphocytes per mm^3
Pressure ~ 50-150 mm water
Volume ~ 125-175 mls
Flow of CSF a in brain
- Lateral ventricle 1
- Septum pellucidum, inter ventricular foramen of Monroe
- Lateral ventricle 2
- 3rd ventricle
- Aqueduct of Sylvius
- 4th ventricle
- Foramina of luschka
- And Foramen of megendie
- Subarachinoid space
CPP = ICP - MABP
As ICP increases, CPP decreases
Herniation of the cingulate gyrus under the fall cerebri
Subfalcine shifts
Medial part of the temporal lobe
Uncus
Symptoms of uncal/transtentorial herniation
- Decreased level of consciousness
- Dilation of the pupil on the side of the herniation
- Fixed pupil on the side of the herniation
Symptoms of tonsillar/transforamina herniation
- Unconscious or rapidly decreasing level of consciousness
2. Abnormalities in heart rate and breathing
Aneurysm of arteries in subarachinoid space ex berry aneurysm
Subarachinoid hemorrhage
*90% in anterior part of artery
Cardinal Symptoms of subarachinoid hemorrhage
- Sudden onset of sever headache (usually during exertion)
- Nuchal rigidity (stiff neck)
- Altered level of consciousness
*on CT crab of death
Most life-threatening head fracture occurs
Base of skull
*can cause leakage of CSF from nose or ears
Epidural hematoma
Lens shaped hematoma on CT Tear of dura from bone Fracture to pterion side of skull Tear middle meningeal artery Most commonly affects area 4 of brain
Symptoms of epidural hematoma
- Initial concussion
- lucidity
- Unconsciousness
Subdural hematoma
- Bleeding of bridging veins between the dura and arachnoid space
- Crescent shape hematoma on CT/MRI
- Occurs from anterior-posterior displacement of brain
- Common in elderly
Bruise of the surface of the brain
Contusion
Concussion also known as
Mild traumatic brain injury
Linked to development of Alzheimer’s and ALS
Head trauma caused by repeated mild traumatic brain injury (TBI), prevalent among professional athletes
Chronic traumatic encephalopathy
Blockage of fluid flow from ventricles to subarachnoid space
Non-communicating or obstructive hydrocephalus
Hydrocephalus caused by increased production or reduced absorption of CSF
Communicating/non-obstructive hydrocephalus
*this can be a potentially life threatening secular to meningitis
Symptoms of meningitis/lepomeningitis
- Lethargy
- Nuchal rigidity
- Severe headache
- Fever
- Increased Sensitivity to light and sound
- Muscle twitching
- Vomiting
- complication - formation of dense adhesions between pia and arachnoid - communicating hydrocephalus
Swelling of the brain is called
Encephalitis
