Transient hepatic intensity differences

Transient hepatic intensity differences (THIDs) are a phenomenon observed on MRI imaging of the liver. They are considered a direct equivalent to transient hepatic attenuation differences (THADs) noted on CT. They may be focal or nonfocal.


Focal lesions

A focal THID lesion can arise from four pathological mechanisms

  • directly by a siphoning effect (lobar multisegmental shape)
  • indirectly by means of portal hypoperfusion (sectorial shape) due to portal branch compression or infiltration
  • by thrombosis resulting in a portal branch blockade
  • by flow diversion caused by an arterioportal shunt
Non focal lesions

These can be sectorial, polymorphous or diffuse and can arise from a veriety of aetiologies.

Share article

Article information

rID: 17528
Synonyms or Alternate Spellings:
  • Transient hepatic intensity differences (THID)
  • THID
  • Transient hepatic intensity difference (THID)
  • THIDs

Support Radiopaedia and see fewer ads

Updating… Please wait.

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.