Objective: To investigate CT and MRI manifestations of Langerhans cell histiocytosis (LCH) involving the liver in children. Methods: CT and MRI findings of 22 children with LCH involving the liver were retrospectively analyzed. Results: Hepatomegaly was found in all 22 children, while widening of Glisson sheath and track sign and halo sign of portal area were observed in 20 cases. CT showed low density in 16 cases, 5 cases showed mild to moderate enhancement, and MRI showed high signal intensity in 4 cases and 2 cases showed mild enhancement of T2WI. Fourteen children presented multiple nodules in the liver, with diameters of 0.51-2.35 cm, distributed along the portal vein in 10 cases and diffusely distributed in 4 cases. Among them, CT showed low densities in 11 cases and 5 cases showed mild to moderate enhancement, while T1WI showed low signal intensities and T2WI showed high signal intensities in 3 cases and 2 cases showed mild enhancement. Intrahepatic bile duct alternative stenoses/dilatation were noticed in 8 cases. Conclusion: CT and MRI findings of LCH involving the liver in children have certain characteristics.

Objective To investigate the application value of magnetic resonance diffusion tensor imaging (DTI) in auditory pathway of sensorineural hearing loss (SNHL) infants caused by cytomegalovirus (CMV) infection.Methods Thirtyone SNHL infants caused by CMV infections were included,and were divided into bilateral hearing loss (BPHL;n=13) group and unilateral hearing impairment (UPHL;n=18) group (including damaged side [lpsi subgroup] and the undamaged side [contrast subgroup]).Thirty-one infants without hearing loss as control group.The fractional anisotropy (FA),the mean diffusivity (MD),the axial diffusivity (AD) and the radial diffusivity (RD) of bilateral inferior colliculus (IC)and lateral lemniscus (LL) were obtained with DTI technique.The statistical analysis was performed.Results Compared with the control group,the FA value reduced and the RD value increased at LL and IC in the BPHL group (all P＜0.001).Compared with the contrast subgroup,the FA value reduced and the RD value increased at IC and LL in lpsi subgroup (all P＜0.001).Compared with the control group,the FA value reduced at LL in the lpsi subgroup,and FA values reduced and RD value increased at IC (all P＜0.001).Compared with the contrast subgroup,the FA value reduced and RD value increased at LL,and RD value increased at IC in the BPHL group (all P＜0.001).The FA value at IC was negatively correlated with auditory threshold (r=-0.966,P＜0.001).No matter in IC or in LL,the MD and AD had no statistical differences (all P＞0.05).Conclusion White matter of auditory pathway of SNHL infant caused by CMV infection is obviously altered,suggesting white matter myelination or myelin dysplasia.