PSYB65H3 Lecture Notes - Lecture 3: Intracerebral Hemorrhage, Transient Ischemic Attack, Brain Tumor

16 views3 pages
18 Nov 2012
Lecture 3
Vascular System Brain Disorders
- blood carries oxygen and sugars => oxygen is most critical bc person can only stay alive ~3 min w/o oxygen
=> brain has a very high metabolic rate, so cannot stay alive w/o oxygen even for very short periods
=> first organ to be damaged from a problem like a heart attack
Types of problems:
1. Cerebrovascular accident (CVA, stroke): severe interruption of blood supply to the brain
=> results in ischemia (not enough blood/not enough oxygen); blood will be missing glucose/o2
=> produces dead/dying tissue/severely damaged tissue – infarct
2. Encephalomalecia: very slow reduction in blood supply, due to long term blockage of arteries due to
=> softening of the brain tissue – some tissue death, but tissue as a whole hasn’t completely died; may see
swelling of tissue
=> incomplete tissue death, some cells may be dying, others healthy
3. Transient ischemic attack: temporary (comes and goes) restriction of blood flow, involving musculature of a
particular blood vessel
=> may occur during severe/migraine headaches
=> vessels constrict, reduction in vision/blurriness in a particular part of the visual field
=> do not cause brain damage – not sufficiently severe
Causes of blood flow disruption:
1. Blockage:
thrombosis: blockage that is locally formed; can form at any one site in the brain, eg blood clot => cause CVA
embolism: blockage that breaks off from a plaque in a remote location away from the brain and travel until it
lodges and blocks an artery in the brain => cause CVA
arteriosclerosis: general clogging of the arteries, occurs more in elderly individuals; if clogged in the brain can
cause encephalomalecia
2. Cerebral haemorrhage:
- burst of blood vessels, results to a loss of blood supply from the cardiovascular system and bleeds into the brain
- can be life threatening, most often associated w high blood pressure =>
critical that blood pressure is controlled
- bleeding into the brain it will kill the brain tissue where its bleeding
3. Subdural hematoma:
- bleeding into the space bw the skull and the brain, bleeding underneath the
- not bleeding inside the brain itself, but outside the brain into the area of the
- doesn’t kill the brain tissue directly, and if caught in time => puts pressure
on the brain
- pressure can be relieved w/o incurring permanent brain damage
- black is lateral ventricle, should be one on the other side, but the hematoma
(white) pushed the brain (grey) so far over that it took over the second lateral
4. Angioma:
- collection/mass of enlarged abnormal blood vessels
- congenital defect – during development, blood vessels tangled/crossed in a small area of the brain
=> can shunt blood in the wrong direction, not always a problem
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Get access

$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
1 Booster Class
$8 USD/m
Billed $96 USD annually
Homework Help
Class Notes
Textbook Notes
30 Verified Answers
Study Guides
1 Booster Class