Eligibility Criteria:
Inclusion Criteria:
* ICH:
1. Age:above 20 years old.
2. Evidence of intraparenchymal hemorrhage on CT or MRI.
3. Patient agrees to participate in the study and receive neurophsychological examinations, genetic and biochemical markers test, MRI and PET imaging.
* AD:
1. Age:above 20 years old.
2. Patients who fulfills the clinical criteria of possible or probable Alzheimer's disease (AD).51
3. Patient agrees to participate in the study and receive neurophsychological examinations, genetic and biochemical markers test, MRI and PET imaging.
* Control:
1. Age:above 20 years old.
2. Patient agrees to participate in the study and receive neurophsychological examinations, genetic and biochemical markers test, MRI and PET imaging.
Exclusion Criteria:
* ICH:
1. patients with potential causes of hemorrhage including trauma, structural lesion, brain tumor, or coagulopathy due to systemic disease or medication.
2. Patients could not receive the PET and MRI studies, including but not limited to poor cooperative agitation impeding adequate study, allergy to contrast medium, hemodynamic instability, implantation of cardiac pacemaker, past history of receiving aneurysm clipping, panic mood to MRI study, impaired kidney function.
3. Patients with pregnancy or recently having a plan for pregnancy.
4. Patients with breast feeding or recently having a plan for breast feeding.
5. Patients with history of allergy to 11C-PiB and 18F-T807, or severe allergy history.
6. Patient or family who does not agree to participate in the study.
7. patient with high risk by doctor evaluate.
* AD:
1. Patients could not receive the PET and MRI studies, including but not limited to poor cooperative agitation impeding adequate study, allergy to contrast medium, hemodynamic instability, implantation of cardiac pacemaker, past history of receiving aneurysm clipping, panic mood to MRI study, impaired kidney function.
2. Patients with pregnancy or recently having a plan for pregnancy.
3. Patients with breast feeding or recently having a plan for breast feeding.
4. Patients with history of allergy to 11C-PiB and 18F-T807, or severe allergy history.
5. Patient or family who does not agree to participate in the study.
6. patient with high risk by doctor evaluate.
* Control:
1. History of neurological or psychiatric disease, abnormal neurological examination.
2. Patients could not receive the PET and MRI studies, including but not limited to poor cooperative agitation impeding adequate study, allergy to contrast medium, hemodynamic instability, implantation of cardiac pacemaker, past history of receiving aneurysm clipping, panic mood to MRI study, impaired kidney function.
3. Patients with pregnancy or recently having a plan for pregnancy.
4. Patients with breast feeding or recently having a plan for breast feeding.
5. Patients with history of allergy to 11C-PiB and 18F-T807, or severe allergy history.
6. Patient or family who does not agree to participate in the study.
7. patient with high risk by doctor evaluate.