RÉSUMÉ
Objective To analyze and compare the independent and combined diagnostic values of high frequency ultrasonography (HFU) and molybdenum target imaging (MTI) for early breast tumor in a prospective study.Methods 258 patients with breast mass which were suspected as breast tumors by physical examination received HFU,MTI,their combined applications and operative treatments.Comparative studies were made between the surgical pathology and imaging evaluations.Results Totally 258 cases were enrolled in this study.Surgical pathology confirmed 135 cases of early breast cancer and 123 cases of benign breast tumor.For the diagnosis of early breast cancer,combined application was more effective than HFU or MTI alone in sensitivity (P0.05).In the patients of early breast cancer, compared with HFU,MTI found less nodules of calcification(18.3% vs 36.5%,P<0.01),but revealed more axillary lymph metastasis (69.0% vs 33.3%,P<0.01).Conclusion HFU and MTI alone or their combined application are reliable imaging methods for the diagnosis of early breast cancer.For the sensitivity and accuracy of diagnosis, combined applications has more superior advantages.
RÉSUMÉ
Objective To establish animal model of arterial vulnerable plaques for molecular imaging study.Methods Fifteen New Zealand white rabbits were randomly divided into high lipid diet+balloon-injury group (A),high lipid diet group (B)and regular diet group (C).Ultrasound (US)and magnetic resonance (MR)imaging were used to dynamically observe the formation of plaque in abdominal aorta. Results were compared with blood lipid level and pathological indicators.Results At 4 weeks,several plaques could be seen in group A.The plaque number increased rapidly and reached to 22 at 12 weeks,which was in parallel with the change of blood lipid. Only a few plaques were observed in group B,while no vulnerable plaque was revealed in group C.All the plaques were judged to be soft plaques on US and MR images,which was consistent with the macrophages gathering and smooth muscle cell proliferating in plaques.Conclusion High lipid diet+balloon-injury is an ideal method to build animal model for molecular imaging of atherosclerotic plaque.
RÉSUMÉ
ObjectiveTo investigate the value of diffusion tensor imaging (DTI) at high b value for unilateral middle cerebral artery (MCA) occlusive disease in patients without obvious infarct lesions on conventional MR imaging.MethodsDTI at high b value (2200 s/mm2 ) was performed using a 3.0 Tesla MR scanner in 34 patients with unilateral middle cerebral artery occlusion,who had no obvious infarct lesions on conventional MR imaging. Fractional anisotropy (FA),apparent diffusion coefficient (ADC),axial diffusivity (eigenvalue λ1) and radial diffusivity (eigenvalues λ2,λ3) were measured at the ipsilateral and contralateral corona radiata,anterior and posterior limbs of the internal capsule,cerebral peduncle and pons in all subjects.Mean ADC,FA,λ1,λ2 and λ3 values of corona radiata,anterior and posterior limbs of the internal capsule,cerebral peduncle and pons were compared between the ipsilateral and contralateral MCAterritory by t test. Results Among the 34 patients,left MCA occlusion in M1 segment occurred in 16 patients and right MCA occlusion in Ml segment occurred in 18 patients.At the ipsilateral corona radiata,mean FA,ADC,λ1,λ2 and λ3 were 0.419 ±0.032,(5.975 ±0.272) × 10 3,(5.704 ±0.365) ×10-3,(6.412 ±0.368) × 10-3 and (6.605 ±0.343) × 10-3 mm2/s,respectively.At the contralateral corona radiata,mean FA,ADC,λ1,λ2 and λ3 were 0.443 ± 0.033,(5.804 ± 0.282) × 10 -3,(5.651 ±0.350) × 10-3,(6.099 ±0.353) × 10-3 and(6.372 ±0.355) × 10-3 mm2/s,respectively.At the ipsilateral corona radiata,mean FA was significantly decreased(t =11.614,P ＜0.01),and mean ADC (t=12.421,P＜0.01),λ1(t =7.447,P＜0.01),λ2(t=10.244,P＜0.01) and λ3(t=9.890,P＜0.01) were significantly increased.At the ipsilateral anterior and posterior limb of the internal capsule,mean FA were 0.609 ±0.026 and 0.674 ±0.033,λ1 were(5.330 ±0.462) × 10 -3 and(5.171 ±0.456) ×10-3 mm2/s,respectively.At the contralateral anterior and posterior limb of the internal capsule,FA were 0.622 ±0.026 and 0.694 ±0.034,λ1 were(5.064 ± 0.448) × 10 -3 and(4.924 ± 0.365) × 10 -3 mm2/s,respectively.Mean FA was significantly decreased (t =7.823,8.013,all P ＜ 0.01) and mean λ1 was significantly increased (t =7.811,8.800,all P ＜0.01) at the ipsilateral anterior and posterior limbs of the internal capsule.There was no significant difference in ADC,λ2 and λ3 value between the ipsilateral and contralateral sides.And all the DTI parameters,including mean ADC,FA,λ1,λ2 and λ3 values,showed no statistical difference between both sides of cerebral peduncle and pons.ConclusionDTI at high b valuc can provide useful information for visualizing ischemic white matter injury in patients without obvious infarct lesions on conventional MR imaging.