6  MRI Technique

6.1 Blood Signal

Figure 6.1: MRI Signal of Aging Blood [1] and blog post

	Time	T1	T2
Hyperacute	< 12 hr	Isointense	Bright
Acute	12 hr - 2 days	Isointense	Dark
Early subacute	2 - 7 days	Bright	Dark
Late subacute	1 wks - 2 mos	Bright	Bright
Chronic	> 2 mos	Dark	Dark

[1]

W.G. Bradley, MR appearance of hemorrhage in the brain, Radiology. 189 (1993) 15–26. https://doi.org/10.1148/radiology.189.1.8372185.