Objective To explore the image features of benign fibrous histiocytoma of bone and its correlative differential diagnosis.Methods Nine cases of benign fibrous histiocytoma of bone were retrospectively analyzed by comparing the imaging findings with surgical and pathological results.Results In all 9 cases,the tumors were single,ranged from 10 mm?15 mm?20 mm to 50 mm?50 mm?60 mm in diameter,which appeared as round or oval destruction with clear border in the bone,neither calcification nor ossification.The border of tumors in 5 cases was accompanied by integrated sclerosis ring with homogeneous thickness.There were expanding changes in 6 cases,no expanding changes in 3 cases.4 cases underwent MRI,2 cases were homogeneous,low signal on both T1WI and T2WI,and 2 cases were low signal on T1WI and high signal on T2WI with low signal sclerosis ring in circumference.There were no periosteum reaction and soft-tissue tumor in 9 cases.Conclusion X-ray,CT and MRI are valuable in the diagnosis of benign fibrous histiocytoma of bone,for some typical cases,the correctly diagnosis of it can be made before operation.

Objective: To investigate the changes of brain gray matter volume in patients with occupational noise-induced hearing loss by voxel based morphometry (VBM) . Methods: 16 age-and education-matched healthy controls and 42 patients with occupational noise induced hearing loss, including 27 in mild group and 15 in severe group, received MRI 3D-FSPGR sequence T1WI sagittal scan, and then underwent VBM of brain gray matter volume data analysis. Results: The brain gray matter volume of the left occipitotemporal lateral gyrus, the anterior cingulate gyrus, the bilateral angular gyrus, the precuneus and the near midline area of cerebellum differed between experimental group and control group (P<0.01) . Conclusion The volume of gray matter in specific brain areas of patients with occupational noise-induced hearing loss was changed, and the effect of noise on brain structure was revealed from the perspective of imaging.

Objective To explore the application of double-parameter three-dimension arterial spin labeling (3D-ASL) in evaluating collateral circulation in patients with unilateral chronic middle cerebral artery (MCA) occlusion.Methods From May 2015 to November 2017,24 patients with unilateral chronic MCA occlusion were scanned in Yantaishan Hospital by conventional MRI,DWI,3D-TOF-MRA and 3D-ASL (post-labeling delays:1.5 s and 2.5 s respectively) using a 3.0 T MR scanner.The cerebral blood flow (CBF) values were measured in region of interest in the occlusive cortical area and in the contralateral normal cerebral area.The differences in CBF value measured by 3D-ASL (PLD=1.5 s and PLD=2.5 s) were analyzed by statistical methods.Results All the patients (n=24) on 3D-ASL (PLD=1.5 s) presented with apparent hypoperfusion in the MCA occlusion territory;but 3D-ASL (PLD=2.5 s) demonstrated the basically same perfusion in bilateral MCA territories,without apparent hypoperfusion in one cerebral hemisphere.The subtraction images of 3D-ASL (PLD 2.5 s-PLD 1.5 s)presented laminated high signal areas in the cortical region of MCA occlusion.There was no statistically significant difference in CBF value of the contralateral normal cerebral area between measurements by 3D-ASL (PLD=1.5 s) and by 3D-ASL (PLD=2.5 s) (6.39±5.01 mL/100 g·min versus 55.87±6.89 mL/100 g· min) (P＞0.05).The CBF value of region of interest in the occluded cortical area (23.34±4.53 mL/100 g· min) was significantly lower than that in the contralateral normal cerebral area (55.87±6.89 mL/100 g·min) by 3D-ASL (PLD=1.5 s) (P＜0.05).The CBF value of region of interest in the occluded cortical area (53.93±8.59 mL/100 g·min) by 3D-ASL (PLD=2.5 s) was significantly higher than that by 3D-ASL (PLD=1.5 s) (23.34±4.53 mL/100 g·min) (P＜0.05).There was no statistically significant difference between the CBF value of region of interest in the occluded cortical area and that in the contralateral normal cerebral area by 3D-ASL (PLD=2.5 s) (P＞0.05).Conclusions 3D-ASL (PLD=1.5 s and PLD=2.5 s) can noninvasively and intuitively demonstrate the collateral circulation compensation in patients with chronic MCA occlusion.3D-ASL (PLD=1.5 s) can reflect the first-order collateral circulation compensation while 3D-ASL (PLD=2.5 s) can reflect accurately the secondary collateral circulation compensation.