MRI manifestations of hepatic perfusion disorders.

The present study aimed to analyze the magnetic resonance imaging (MRI) results from patients with hepatic perfusion disorders (HPD) and liver diseases, in order to assess the pathogenetic mechanisms. This was completed byanalyzing the causes of HPD in 35 patients to assess if they were associated with arterioportal shunt, and classify the patients according to results from the MRI scans. Of the 35 patients, 26 (74.3%) with HPD presented with hepatocellular carcinoma, a major cause of HPD. The HPD phenomenon in 35 patients was not identified as obvious abnormal lesions on T2WI and T1WI according to the isointensity on diffusion weighted images. Enhanced scanning showed hyperintense signals on the arterial phase images, isointense or hyperintense signals on portal phase and delayed phase images. According to their MRI findings, hepatic perfusion disorders may be divided into different types, as follows: Diffuse, lobe or segment type, wedge type and platy. The HPD phenomenon may herald an underlying abnormality of liver disease and MRI may accurately diagnose HPDs in liver diseases.

Heat stroke: typical MRI and (1)H-MRS features.

Heat stroke (HS) is a life-threatening condition characterized by severe hyperthermia associated with central nervous system abnormalities. We present two interesting cases of HS with symmetric lesions in the dentate nuclei and cerebellar peduncles. Typical MRI and (1)H-MRS features including follow-up studies are illustrated.

Diffusion tensor imaging of the cerebellum in patients after heat stroke.

To explore the application value of cerebellar diffusion tensor imaging (DTI) in patients after heat stroke (HS). Eleven patients after HS with a score of 3-9 in Glasgow Coma Scale (GCS) and seven age-matched healthy volunteers were selected to undergo MR examinations during the same hot summer. The MR studies including DTI were performed with a 1.5 T scanner. Fractional anisotropy (FA) values of normal-appearing cerebellar white and gray matter were measured and the differences between the two groups were evaluated with Mann-Whitney U test. The FA value of normal-appearing cerebellar white matter in patients after HS was found to be decreased compared to normal control subjects (652.5 ± 86.1 vs 769.5 ± 58.4, p = 0.025). The FA value of normal-appearing cerebellar gray matter in patients after HS was found to be decreased compared to normal control subjects (158.8 ± 27.9 vs 187.5 ± 15.8, p = 0.040). Neural damage of the cerebellum induced by HS may be effectively evaluated by DTI with the decrease of FA value in normal-appearing cerebellum structures.