Hepatic encephalopathy: what should the radiologist know?

This poster is published under an open license. Please read the disclaimer for further details.

Congress:

ECR 2016

Poster Number:

C-1352

Type:

Educational Exhibit

Keywords:

Metabolic disorders, Cirrhosis, Diagnostic procedure, MR-Spectroscopy, MR-Diffusion/Perfusion, MR, Neuroradiology brain

Authors:

L. Farras Roca¹, J. J. Sánchez Fernández², P. Puyalto³, P. Mora Montoya², M. Cos Domingo², C. M. Grassi Zamora², D. S. Palominos Pose², J. C. Sardiñas Barrero², C. Majós Torró²; ¹Barcelona/ES, ²L\' Hospitalet de Llobregat-Barcelona/ES, ³Badalona/ES

DOI:

10.1594/ecr2016/C-1352

DOI-Link:

https://dx.doi.org/10.1594/ecr2016/C-1352

Fig. 1: Axial MRI, T2 weighted image (A) and FLAIR (B), showing moderate signs of...

Fig. 2: Axial MRI T1 weighted image (A) and FLAIR (B) demonstrating a subtle...

Fig. 3: Axial FLAIR MRI in a patient with hepatic encephalopathy demonstrating...

Fig. 4: Axial MRI FLAIR sequences (A,B,C) show a diffuse gray matter hyperintensity and...

Fig. 5: Axial MRI FLAIR sequences (A,C,D) and diffuse sequence (B) show a diffuse white...

Fig. 6: Sagital T1 weighted image showing a small pituitary gland with a diffuse...

Fig. 7: Proton MR spectroscopy of an hepatic encephalopathy, demonstrating an elevated...

Fig. 8: A comparative FLAIR axial images, showing on the left (A) a patient affected by...

Learning objectives

To review the clinical setting and MRI typical findings of hepatic encephalopathy (HE). To review the more classical MRI features of acute toxic and acquired metabolic encephalopathies in order to provide the radiologist the skills to differentiate each entity.

Background

Hepatic encephalopathy can occur in the setting of acute fulminant hepatic failure or as a more chronic disease, which is usually a more indolent process. Although its pathogenesis is not clear and many hypotheses have been proposed, the physiopatothology is thought to be due to the cerebral edema and raised intracranial pressure caused by an increased intracellular osmolytes, which are usually metabolized by the liver, such as manganese and ammonia. The clinical manifestations are secondary to a misbalance between inhibitory and excitatory neurotransmission. This misbalance...

Findings and procedure details

MRI can show a specific pattern of cerebral metabolic changes and measure abnormal deposits of different substances that under normal circumstances are metabolized by the liver. T1-weighted images show hyperintense signal in the globus pallidus, subthalamic region and midbrain (Fig. 1,2,3). The increased T1 signal is due to a rise in manganese concentration (a paramagnetic substance), with preferential deposition in the globus pallidus and substantia nigra. This finding has also been seen in patients receiving total parenteral nutrition, those with occupational exposure to manganese from...

Conclusion

MRI plays an important role in the diagnosis of acute encephalopathic patients. The knowledge of the typical MRIfindings is essential for an accurate diagnosis.Often the image diagnosis can be a challenge for the radiologist, but understanding the characteristic imaging features coupled with a detailed clinical history, can often help to establish the correct diagnosis.

Personal information

References

A. Rovira, J. Alonso, J. Córdoba. MR Imaging Findings in Hepatic Encephalopathy. Am J Neuroradiol 2008; 29:1612-21. P. Sharma, M. Eesa, J. N.Scott. Toxic and Acquired Metabolic Encephalopathies: MRI appearance. AJR 2009; 193:879-886. A.M. McKinney, B.D. Lohman, B.Sarikaya, E.Uhlmann, J.Spanbauer, T.Singewald, J.R.Brace. Acute Hepatic Encephalopathy: Diffusion-Weighted and Fluid-Attenuated Inversion Recovery findings, and correlation with plasma ammonia level and clinical oucome. Am J Neuroradiol 2010; 31:1471-79. T. Naegele, W. Grodd, R. Viebahn, U. Seeger, U. Klose, D. Seitz, S. Kaiser, I. Mader, J. Mayer, W. Lauchart,...