The Experiment Study Of Magnetic Resonance Imaging With Pathologic Correlation In The Margin Of Malignant Bone Tumors

Objective To observe the medullary extent of rabbit VX2malignant bone tumor by the modalities of magnetic resonance imaging (MRI) and pathology so as to investigate the role of MRI in displaying the margin of malignant bone tumor. Materials and methods Twenty-five rabbits were used to erect experimental phantom. The tumor was implanted into the proximate metaphysis of right tibia. Radiological examinations were taken after four to five weeks. The sweep sequences included SE T1WI、Fat-Sat FSE T2WI、STIR、 Fat-Sat SE T1WI+C. After the examination, experimental rabbits would be put to death immediately and taken pathological examination. The medullary margin of tumor was measured from the most distal site to the tibial plateau. Statistical study was processed with statistical software SPSS17.0. Result (1) No statistical significance was found among all series of MRI (F=0.802, P=0.497>0.05). The average of tumor margin in marrow cavity with group SE T1WI、Fat-Sat FSE T2WI、 STIR、Fat-Sat SE T1WI+C were (44.5±10.8)mm、(41.0±9.7)mm、(40.7±9.4)mm、(40.3±9.5)mm, respectively.(2) Statistical significance were found between the difference of tumor margin in group SE T1WI、Fat-Sat FSE T2WI、STIR、Fat-Sat SE T1WI+C and pathological sample(t=7.05、 6.34、6.45、8.15, P<0.05).(3) The sensitivity of group SE T1WI and group Fat-Sat SE T1WI+C was58.3%、88.9%, respectively. The specificity of group SE T1WI and group Fat-Sat SE T1WI+C was44.4%、100%, respectively.(4) The average difference of tumor margin between group SE T1WI and group pathology、group Fat-Sat FSE T2WI and group pathology、 group STIR and group pathology、group Fat-Sat SE T1WI+C and group pathology was5.2mm、1.7mm、1.5mm、1.0mm, respectively. Conclusion (1) The accuracy of MRI in displaying the tumor margin in marrow savity of malignant bone tumor was rational.(2) Both sensitivity and specificity of Fat-Sat SE T1WI+C were highest among all the sequences of MRI.(3) Fat-Sat SE T1WI+C was the optical scanning sequence in displaying the tumor margin of malignant bone tumor.