Cause of brain dysfunction Flashcards
Encapsulated tumors
- Tumors, aka neoplasms
- Grow between the meninges
- Encapsulated - tend to be benign (not growing super fast/ aggressive, when removed, it won’t grow back)
Infiltrating tumors
Infiltrating tumours
Grow diffusely through surrounding brain tissue
Malignant
Infiltrating tumors
Tendrils in the tumors
In certain aggressive tumors, the boundaries between healthy tissue and the tumor are indistinct, making it difficult to determine where healthy tissue begins and where the tumor’s tendrils end.
impossible to remove all of the tumor, resulting in a high likelihood of recurrence
Metastatic tumors
- Some infiltrating brain tumors grow from tumor fragments carried to the brain from another body part via the bloodstream
- Commonly originate from a breast cancer or a lung cancer
Glioblastoma (glioma)
- Most common type of malignant brain tumors in adults (aka glioma)
- Median survival rate: 14 months (short survival rate)
- Most malignant
- Grows in CNS
Stroke
sudden-onset cerebrovascular disorders than cause brain damage
Stroke
Infarct
no longer any blood flow coming, area of dead/ dying tissue
Stroke
Penumbra
dysfunctional area surrounding the infarct; tissue in penumbra may either recover or die
Types of stroke
- Ischemic
- Hemorrhagic
What is Ischemic stroke
resulting from cerebral ischemia (blocked blood flow)
What is a Hemorrhagic stroke
- Resulting from cerebral hemorrhage (rupture in or around tissue)
- Additional problem: blood itself is toxic, bleeding into the brain
- Most common cause: aneurysm
Cerebral hemorrhage
What is aneurysm
- Water balloon swelling in our brain→ stretched out by blood
- Can be congenital or develop later
-** Commonly at base of brain** (e.g. Circle of Willis) - Risk factors: diabetes, hypertension, smoking cigarettes, alcoholism, aging (big predictor)
Cerebral hemorrhage
What is clipping?
-Open head surgery
- Pinch neck of aneurysm with titanium clips, all the blood will stay there and the blood will clot itself, close up
- Lower rate of recurrence
- 60-80 yr old can’t handle full anesthetic anymore because have anesthesia the whole body
Cerebral hemorrhage
What can treat cerebral hemmorhage
- Clipping
- Endovascular coiling
Cerebral hemorrhage
What is endovascular coiling?
- Much less invasive, less risk
- Slightly higher rate of recurrence than option 1
- Only surgical cutting is at the femoral artery (largest artery we have) insert tube into femoral artery and drive all the way up to brain with real time x ray→ driven to the site of aneurysm, unspools platinum coil into the aneurysm itself→ cause any blood in the aneurysm to clot together so no blood could come in again
3 main causes of cerebral ischemia
A disruption of blood supply to some area of the brain
Three main causes:
1. Thrombosis: a plug; blood clots block your blood vessels
2. Embolism: a moving thrombosis; refers to air bubble, fat, air tissue
3. Arteriosclerosis; narrowing of arteries, cholesterol thickening of arteries
3 can interact with 1 or 2
Ischemia-produced brain damage
- It takes a while to develop (can be days) - build up as malaise over days
- Damage is more likely in some parts of the brain (e.g. hippocampus- sensitive to insults related to stress, mental health)
- The mechanisms of ischemia-induced damage vary between brain structures (one example: excitotoxicity and apoptosis)
Autoreceptors important for negative regulating→ when it’s overwhelmed, we have these receptors for glutamates, some will be the NMDA receptors, let calcium into the cell triggers self destructing mechanisms (apoptosis)
Open-head injuries
- Aka penetrating (something entered into your skull), perforating (entered into your skull and comes out at another part) head injuries
- Typically very severe gunshots succumb to injuries at the site of crime
- High risk of infection, complications
- High velocity objects worse than low (speed of it)
Classic example: phineas gage
Close-head injuries
Contusion
Closed-head injuries that involve damage to the cerebral circulatory system
type of hemorrhage or hematoma- solid swelling of blood
When do contusions occur?
- Occurs where the brain slams against the skull
- It can be between meninges and skull (epidural), meninges and brain (subdural), within brain (intracranial)
-If you slam into something, your brain slams to the opposite side of head; hit immovable object (coup contrecoup), injury on the impact and also at the opposite side
Close-head injury
Mild traumatic brain injury (mTBI)
No obvious evidence of contusion or injury (bleeding in the brain) but have symptoms; relatively normal
Close-head injury
What is synonymous to concussions?
Mild traumatic brain injury (mTBI)- a checklist, collection of symptoms
- Can disrupt sleep, sensitivity to light, sleep problems, fatigue, headache, appetite