SOLs Flashcards
SIGNS of RAISED ICP? (4)
Papilloedema, Headache, N.V, Stiff Neck
Name the dif. forms of herniation? (4)
Subfalcine, Tentorial, Cerebellar, TransCalvarial
Where is Hydrocephalus Ex Vacuo seen?
Alzheimer’s Disease
Name 4 kinds of SOLs
Tumors/Abscess/Hematomas/Localized brain swelling (EDEMA around infarct)
70% of childhood brain tumors arise from ________
BELOW the tentorium cerebelli
—WHILST 70% OF ADULT CNS tumors= ABOVE
Where do brain tumors usually metastasize from?
breast, bronchus, kidney, thyroid, colon carcinomas and MALIGNANT melanoma
Most common malignant primary intracranial tumors in KIDS and ADULTS
ASTROCYTOMA (45-50%) and oligodendroglioma (1-6% incidence)
Why do high grade tumors cause edema?
- they interfere with the integrity of the BBB, causing vasogenic edema
Name a grade 1 Astrocytoma. Can this become malignant?
Pilocytic Astrocytoma —no remains benign
Name a distinct histological ft of High grade tumors.
neo-angiogenesis- so very vascular tumors
Name 3 fts of a Medulloblastoma
- radiosensitive
- arises Midline of cerebellum
- poorly differentiated cells (EMBRYONAL cells)
Best management of Medulloblastoma
75%, 5 year survival with RESECTION and RADIOTHERAPY
Causes of Single Abscesses
- Local Extension (mastoiditis)
2. Direct Implantation (skull #)
Name 2 conditions which may cause Multiple Abscess formation
HEMATOGENOUS spread:
- Bronchopneumonia
- Bacterial Endocarditis
- —also seen at the boundary of G-W matter
How to manage brain abscesses?
- CT/ MRI to confirm
- aspiration for CULTURE and rx
- weeks of antibiotics
What organism usually causes ear abscesses?
B.Fragilis
What usually causes peripheral abscesses and deep abscesses?
peripheral- Bacterial
deep (basal ganglia)- Toxoplasma
How does meningitis cause raised ICP?
Becauses it causes edema and arachnoiditis–> lack of CSF absorption and therefore hydrocephalus
Gram +ve Cocci cause of bacterial meningitis in older adults/ children
Strep. Pneumoniae
Gram - rods cause of Meningitis
E.coli
Gram -ve cocco bacilli that causes bact. meningitis in KIDS
H.influenzae
What gram - diplococci commonly infects young children and aldolescents?
Neisseria Meningitidis
How does high vs low velocity missile injury differ?
High velocity penetrating wound, causes FAR MORE DAMAGE to the surrounding tissue than a low velocity wound; the SMALLER the contact time THE LARGER the force
Name the 3 types of skull fracture
- Linear - straight sharp #; but NO movement of bone
- Compound- full thickness scalp lacerations
- Depressed
What risk does a Linear Fracture hold?
Risk of potentially RUPTURING the Middle Meningeal Artery
Where does DIFFUSE AXONAL INJURY usually occur?
in central areas of the brain, at moment of injury
Main difference between Epidural and Subdural Hematoma?
Epidural - accumulation of ARTERIAL blood
Subdural is accumulation of venous blood
Common Extradural hematoma
fracture of the pterion bone on the tempero-parietal region causing the rupture of the Middle Meningeal Artery
What occurs if you leave an extradural hematoma untreated?
- compression, midline shift and herniation
- mortality of 10-20%
Subdural hemorrhage involves what blood vessels?
It involves the disruption of the BRIDGING veins which extend from the brain surface into the subdural space…between dura mater and arachnoid mater
What is different about an Acute Subdural hematoma and a Chronic one?
Chronic subdural hematoma results in prodn of a yellow fluid called Neomembrane
What occurs in Cerebellar Tonsil Herniation?
Caused by increased pressure in the POSTERIOR fossa forcing cerebellar tonsils out through the foramen magnum.
What is the presentation of a Cerebellar Tonsil Herniation?
Ataxia/ VI CN palsy/
+Babinski’s>loss of consciousness
-apneoa/ irregular breathing
Subfalcian herniation is caused by a _______
Frontal Mass—the cingulate gyrus is forced under the rigid falx cerebri…..SILENT until anterior cerebral artery is compressed and causes STROKE (==> c/l LEG weakness and abulia)
Why does hydrocephalus develop secondary to Alzheimer’s disease?
- d.t LOSS of brain parenchyma in AD
- –> dilatation of the VS and compensatory INCR. in CSF volume
What are the effects of RAISED ICP?
- intracranial SHIFTS and HERNIATIONS- CONING
- midline SHIFT
- PRESSURE on CRANIAL nerves and vital neurological centres
- impaired blood flow (CPP= MAP- ICP)
- Reduced level of consciousness
What are the common fts of brain tumors?
- focal symptoms (70%)
- HEADACHE (50%)
- seizures (30%)
- vomiting
- visual disturbances
—-PAPILLOEDEMA
and focal deficit
Name 2 fts of metastatic brain tumors.
- multiple
2. often seen in the BOUNDARIES between grey and white matter
What is the grading of prmary brain tumors based on?
- Mitoses
- Neovascularisation
- Necrosis
- Atypia
Name the most common benign adult brain tumor?
- Meningioma and Pituitary adenoma
Most common benign children tumor?
craniopharyngioma
List the 4 genetic mutations that predispose a person to v. agressive brain tumors?
- IDH1
- P53
- PDGFRA
- PI3KCA
Histologically, palisading of the cells is commonly seen in which brain tumor?
- Glioblastoma
2nd most common tumor in children AFTER pilocytic astrocytomas.
- medulloblastoma
20% of pediatric CNS neoplasms
What is seen morphologically in brain abscesses?
- central necrosis
- edema
- fibrous capsule
What are the symptoms of abscesses?
- fever
- raised ICP
What is seen in the CSF in bact. meningitis?
- abundant polymorphs
- decr. glucose
Causal organism for bacterial meningitis in NEONATES?
- E-COLI
Possible, gram +ve rod, causal pathogen for bacterial meningitis in an older person?
Listeria Monocytogenes
What is the relation between time of force of contact in blunt injuries of the brain?
- the SMALLER the contact time; the LARGER the force
- —-so the brain moves within the cranial cavity and makes contact with the inner table of the cranium and BONY protrusions
What is primary injury?
- the direct impact that has occurred TO the NEURONES
- —irreversible
Examples of primary injuries to the brain>
- diffuse axonal injury
- diffuse VASCULAR injury
- surface contusions/ lacerations
- petechial hemorrhage
How is a linear # managed?
- no interventions needed
- pts pbserved for a while
- back to normal activities
What is diastatic #?
- when the # occurs ALONG the suture lines of the skull
-
Name the most SERIOUS skull #?
- basillar skull #
What is coup and contracoup?
- coup : occurs to the brain on the SIDE of the IMPACT
- contracoup: diamtrically OPP. point of impact
Why are contracoup injuries worse?
- theory: denser CSF moves to coup side 1st –FORCING brain to contra-coup side
- Cavitation theory—- low pressure at side of contr-coup creates CAVITATION bubbles ==> damaged parenchyma
What may occur post DAI?
-as many as 50% develop COMA after trauma
- to be d.t white matter damage and DAI
- reduced consciousness
> vegetative state
