Diagnostic value of Vascular functionnal parameters in dynamic contrast-enhanced MRI for pituitary microadenomas

ZHANG Yumei; WANG Qing; HE Jingzhen; WANG Fang; WANG Jieqiong; XU Xinghua

Abstract：Objective To investigate quantitatively microvascular parameters in pituitary microadenomas by dynamic contrast -enhanced magnetic resonance imaging ( DCE-MRI) .Methods MRI date was analyzed in 20 normal female adenohypophysis , 24 patients with hyperprolactinemia and 34 patients with pituitary hyperprolactinemia microadenomas conformed with clinical , labora-tory examination or diagnostic treatment retrospectively .The microvascular function parameters of pituitary gland ( volume transfer constant, Ktrans;extravavascular extracelluar volume fraction , Ve;rate constant, Kep;time to peak, TTP) were obtained.A t test was used to compare the difference of parameters between microadenomas and its surrounding pituitary tissue .Analysis of variance ( ANOVA ) was used to evaluate the difference of parameters among these three groups and the difference of parameters of left, median and right pituitary gland in control group .Least significant difference ( LSD) was used for pairwise comparison .The sensi-tivity and specificity of each parameter in diagnosing pituitary microadenomas were analyzed by ROC curve .A P value of ≤0.05 was considered significant .Results 1) TTP value was significantly lower in media pituitary gland than that in left and right pitui -tary gland;2) Ktrans and Kep value of pituitary microadenomas were significantly lower and TTP value of pituitary microadenomas was significantly higher than those of their surrounding tissue respectively;3) Ktrans and Kep value were significantly lower and TTP value was significantly higher in microadenomas group than those in both hyperprolactinemia and control group .There was no sig-nificant difference in Ktrans, Kep and TTP between hyperprolactinemia and control group;4) The diagnostic efficacy of Ktrans and Kep was significantly higher than that of TTP for micro-adenomas.The diagnostic efficacy of the combined use of K trans-Kep was sig-nificantly higher than that of the combined use of K trans-TTP, and TTP and Kep, respectively.The diagnostic efficacy of the com-bined use of K trans-Kep-TTP was the highest for microadenomas .Conclusion The vascular functionnal parameters in DCE-MRI could quantitatively analyze the microvascular change of pituitary microadenomas , parameter Kep show higher diagnostic efficacy and the combined use of multi-parameters is helped to improve the diagnosis of pituitary microadenomas .