The Study Of The Value Of The Three Dimensional Volume T2Flair Enhancement Sequence In The Diagnosis Of Brain Metastasis Of Pulmonary Cancer With Half-dose Contrast

PurposeTo study the value of the three dimensional volume T2Flair sequence in the diagnosis of brain metastasis from pulmonary cancer with half-dose contrast material.Materials and MethodsFrom june 2009 to january 2010, we gathered 21 patients with brain metastasis from pulmonary cancer. Two radiologists reviewed the set of precontrast conventional axial T1WI, T2WI,2DT2Flair, sagittal T1WI, postcontrast T1WI images on a workstation(session 1). Then after session 1, precontrast conventional axial T2WI, 2DT2Flair, together with pre-and postcontrast 3D T1BRAVO were interviewed (session 2). In the end, conventional axial T1WI, T2WI, sagittal T1WI, together with pre-and postcontrast three dimensional volume T2Flair images were interviewed(session 3). The brain metastasis, acording to the locations of the tumor, classified into the tumor in the deep brain parenchyma and the tumor in the brain parenchyma near the subarachnoid space(include the tumor in the subcortex which the distance between the tumor and the cortex is less then 0.5cm and the tumor in the meninges). The number of the tumors detected during three sessions was analysed by the software SPSS 13.0, with the method of Rank-sum test. When the value of P<0.05, the difference is belived statistical significant..In order to determine the underlying mechanisms of the experimental results, glass tube phantoms filled with solutions of varying concentrations of gadopentetate dimeglumine and the head of the volunteer were scanned with the same imaging parameters. The signal intensity of the various gadopentetate dimeglumine solutions compared with that of normal brain is plotted versus gadopentetate dimeglumine concentration.ResultsFor the total number of brain metastases, session 3>session 2>session 1. There are significant statistical difference for the difference between session 1 and session 3 and for the difference between session 2 and session 3 for the number of brain metastases, but there is no significant statistical difference for the brain metastases between session 1 and session 2. To determine the underlying mechanisms of the experimental results, we found that the degree of contrast enhancement of the three dimensional volume T2Flair sequence was more obvious than SE sequence,2DT2Flair sequence and 3D T1 BRAVO sequence.ConclusionThe three dimensional volume T2Flair sequence possess much higher sensitivity than3D T1 BRAVO sequence and normal T1WI enhancement sequence in aspect of detecting brain metastasis, and possess highter power in aspect of rule out he CSF and venous pulsation artifact, and it is more sensitive to lower concentration of contrast materal. There is great potential value for the three dimensional volume T2Flair sequence in the diagnosis of brain metastasis from pulmonary cancer.