1. Hyperdensity on CT scan: blood - amyloid angiopathy 
-Amyloid builds up in blood vessels, weakening them.
-Most common in older people, and generally lobar. If the bleed is in the deep brain or cerebellum, this is much less likely
-Classic story is someone who comes in with recurrent lobar hemorrhages.
-Diagnosis of exclusion-- as you can only formally diagnose with a tissue sample.
2. Hyperdensity on CT scan: blood - hypertensive hemorrhage
-Most common places for hypertensive hemorrhage: (1) basal ganglia/putamen (2) thalamus (3) pons (4) cerebellum.
-Lenticulostriate
-Common in older people with a history of hypertension.
3. Hyperdensity on CT scan: blood - coagulopathy 
-Find out if the patient is on anticoagulation, check coag labs. Remember that some of the new direct thrombin inhibitors can't be monitored by blood tests, and that they were recently recommended as first-line treatment for a-fib by the american chest physicians guidelines.
4. Hyperdensity on CT scan: blood - hemorrhagic infarct
-About 20-30% are ischemic infarcts that converted to hemorrhagic
-Most of the rest are people who had a history of ischemic infarcts, that they then bled into as a result of starting anticoagulants.
-You will not see much mass effect with these.
5. Hyperdensity on CT scan: blood - vascular malformations
-Aneurysm: you will almost always see some subarachnoid blood with aneurysmal bleeds. If you look at the cisterns and they are all clear of blood, this is much less likely. Aneurysms at the MCA bifurcation may rupture into the brain and present as a temporal lobe hematoma due to the vessels being semi-embedded into the temporal lobe.
-AVM: you will not see much mass effect; the bleeding is usually within the AVM.
-Cavernoma/CCM: little mass effect, usually presents with microbleeds, rarely will you get clinically significant bleeds
-Other rarer entities: venous angioma, capillary teleangiectasias, hemangiomas; these are rarer and generally benign.
6. Hyperdensity on CT scan: blood - tumor
-Usually there is significant edema, and there will be noticeable mass effect from both the tumor mass and the surrounding edema.
-Benign tumors are less likely to have severe edema/mass effect than malignant.
7. Management of suspected intracranial hemorrhage: Step 1: stabilize
Airway, breathing, circulation
Airway, breathing, circulation
Airway, breathing, circulation
8. Management of suspected intracranial hemorrhage: Step 2: figure out if they need emergency surgery 
-Supratentorial bleeds rarely do, unless there is significant mass effect leading to herniation or threatened herniation.
-Posterior fossa bleeds- check for
(1) brainstem compression (look at cistern in front of the brainstem- cerebellopontine cistern, cerebellomedullary cistern). If present, this person will require an emergency decompressive posterior fossa craniectomy.
(2) signs of hydrocephalus from compression of 4th ventricle. Look at the 4th ventricle and the aqueduct to make sure they are open. If they have hydrocephalus, they will need an EVD soon but it's not quite as emergent.
9. Management of suspected intracranial hemorrhage: Step 3: Medical optimization 
-Blood pressure should be high enough to perfuse their brain (esp if there is an ischemia component to the stroke) but low enough that it won't worsen the hemorrhage. If the person has a long-standing history of hypertension, you will want to keep their pressures higher than in someone who doesn't to ensure adequate perfusion. Currently, keeping systolic <160 seems to be a good compromise between the increased ischemia at 140 and the increased hemorrhage at 180.
-Reverse anticoagulation: If they were on an antiplatelet agent, transfuse platelets. If they were on an anticoagulant, transfuse factors. It's important to know the reason for the anticoagulation, and to weigh the risk of an adverse cardiac event against an adverse neurological event. Fresh cardiac stents have a 10-15% risk of clotting off with a platelet transfusion, which may not be worth it with a small cerebral hemorrhage; while embolic events in patients with a-fib are rare, and will be outweighed by even a small cerebral hemorrhage.
10. Management of suspected intracranial hemorrhage: Step 4: imaging to determine etiology
-MRI +/- contrast to rule out tumor
-CT angio to rule out vascular malformation
-Coagulation workup
-If all your tests are negative, hypertensive hemorrhage or hemorrhagic infarct are the most likely. Teh management is the same (see step 3).
-It's important to get follow up imaging 2-3 weeks after the bleeding event (both MRI and CT angio) as a fresh bleed can hide a tumor or a vascular malformation (ex: aneurysms can thrombose in an acute setting, and be hidden on CT angio). This is especially important in younger, otherwise healthy people.
(from ricky)