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Cerebral oedema in minimal hepatic encephalopathy due to extrahepatic portal venous obstruction

Amit Goel1, Santosh Yadav, Vivek Saraswat

  • 1Department of Gastroenterology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.

Liver International : Official Journal of the International Association for the Study of the Liver
|June 12, 2010
PubMed
Abstract

Insights

Minimal hepatic encephalopathy (MHE) affects nearly half of patients with extrahepatic portal venous obstruction (EHPVO). Brain imaging reveals interstitial cerebral edema linked to high ammonia levels in MHE patients.

Area of Science:

  • Neurology
  • Gastroenterology
  • Radiology

Background:

  • Minimal hepatic encephalopathy (MHE) is increasingly recognized in patients with extrahepatic portal venous obstruction (EHPVO).
  • Understanding the brain changes associated with MHE in EHPVO is crucial for patient management.

Purpose of the Study:

  • To investigate brain alterations using magnetic resonance (MR) techniques in patients with EHPVO.
  • To correlate these findings with MHE status and blood ammonia levels.

Main Methods:

  • 31 EHPVO patients and 23 controls underwent neuropsychological tests, blood ammonia level measurement, critical flicker frequency (CFF) assessment, 1H-MR spectroscopy, diffusion tensor imaging (DTI), and magnetization transfer ratio (MTR) imaging.
  • MHE was diagnosed using neuropsychological tests.

Main Results:

  • 45% of EHPVO patients had MHE, with significantly higher blood ammonia levels compared to those without MHE.
  • 1H-MR spectroscopy showed elevated Glx/Cr and decreased mIns/Cr in MHE patients.
  • DTI and MTR revealed increased mean diffusivity (MD) and decreased MTR in MHE patients, indicating interstitial cerebral edema (ICE), which correlated with ammonia and Glx levels.

Conclusions:

  • MHE is prevalent in EHPVO patients, but CFF is an insensitive marker.
  • Interstitial cerebral edema (ICE) is present in EHPVO, particularly in those with MHE.
  • Hyperammonemia appears to be a key factor contributing to ICE in EHPVO.

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