Brain MR imaging changes in patients with hepatic schistosomiasis japonicum without liver dysfunction.

BACKGROUND

The hyperintense signal on T1-weighted magnetic resonance (MR) images in the globus pallidus and substantia nigra of the brain can be found in patients with liver cirrhosis. The abnormality has been considered resulting from the manganese (Mn) deposition caused by liver failure and portal-systemic shunting. However, similar finding may also be found in hepatic schistosomiasis patients, who lack the biochemical evidence of liver dysfunction.

OBJECTIVES

To describe the brain MR imaging findings in patients with hepatic schistosomiasis japonicum (HSJ) without liver dysfunction.

METHODS

Brain MR and CT images of 18 patients with HSJ without liver dysfunction and 9 healthy volunteers were reviewed by two radiologists in consensus. The signal index (SI) in globus pallidus was obtained on T1-weighted images. Whole blood Mn, serum iron, serum calcium, and other laboratory tests of liver function were investigated.

RESULTS

Symmetric hyperintense signal in the globus pallidus and substantia nigra was observed in 15 of 18 HSJ patients (83.3%) and in none of controls on T1 weighted imaging. No abnormal CT findings were seen in both groups. Blood Mn level in patients was significantly higher than controls (p<0.05). Significant correlations were demonstrated between blood Mn and SI (p<0.05). No significantly abnormal results of serum iron, serum calcium and other laboratory tests were shown (p>0.05).

CONCLUSION

The portal-systemic shunting leading to Mn deposition may be the main cause of the basal ganglia hyperintense signal on T1-weighted MR imaging, which is a frequent finding in patients with HSJ without liver dysfunction.