Aging blood on MRI (mnemonic)

Ageing blood on MRI is dependentdependant on the varying MRI signal characteristics of haemorrhagic collections with time and can be very useful in correlating the imaging findings with the clinical picture. However, as it can be complicated to recall the MRI features of ageing blood through the five stages of haematoma evolution several mnemonics have been devised:

• I Be, IdDy, BiDy, BaBy, Doo Doo
• I Bleed, I Die, Bleed Die, Bleed Bleed, Die Die
• I BID BaD BaBy DO
• I Bleed, I Die, But Department Boss Bleeds, Department Dies

Mnemonic(s)

The first two mnemonics use the first letters of the words and word pairs to denote the signal characteristics of blood at each stage as isointense (I), bright (B), or dark (D). The first bold letter in each pair denotes the typical T1 signal finding, while the second denotes the T2 signal change.

1. I Be
   • T1 Isointense
   • T2 Bright
   • hyperacute < 1day
2. IdDy
   • T1 Isointense
   • T2 Dark
   • acute 1 to 3 days
3. BiDy 
   • ​T1 Bright
   • T2 Dark
   • early subacute 2 to 7 days
4. BaBy 
   • T1 Bright
   • T2 Bright
   • late subacute 7 to 14-28 days
5. Doo Doo 
   • ​​T1 Dark
   • T2 Dark
   • chronic >14 to 28 days

For those that find it difficult to memorise the mnemonic above an alternative is found below which uses full word pairs.​

• I Bleed 
  • T1 Isointense
  • T2 Bright
  • hyperacute < 1 day
• I Die
  • T1 Isointense
  • T2 Dark
  • acute 1 to 3 days
• Bleed Die 
  • ​T1 Bright
  • T2 Dark
  • early subacute 2 to 7 days
• Bleed Bleed 
  • T1 Bright
  • T2 Bright
  • late subacute 7 to 14-28 days
• Die Die
  • ​​T1 Dark
  • T2 Dark
  • chronic >14 to 28 days

This mnemonic uses bold capital letters of the sentence in pairs of two to denote the signal characteristics of blood at each stage as isointense (I), bright (B), or dark (D). The first bold letter in each pair denotes the typical T1 signal finding while the second denotes the T2 signal change.

• I B
  • T1 Isointense
  • T2 Bright
  • hyperacute < 1 day
• I D
  • T1 Isointense
  • T2 Dark
  • acute 1 to 3 days
• BaD 
  • ​T1 Bright
  • T2 Dark
  • early subacute 2 to 7 days
• BaBy
  • T1 Bright
  • T2 Bright
  • late subacute 7 to 14-28 days
• DO
  • ​​T1 Dark
  • T2 dark (O represents the haemosiderin ring)
  • chronic >14 to 28 days

See also

• ageing blood on MRI