动态增强MRI对眼眶肿块的诊断价值

目的评价动态增强MRI检查对眼眶良、恶性肿块的诊断价值。方法经病理证实的眼眶肿块共89例,男35例,女54例。常规MRI检查后采用3D快速扰相梯度回波(FSPGR)序列进行动态增强扫描,获得动态增强曲线(TIC),计算峰值时间(Tpeak)、最大上升斜率(Slope)、流出率(WR)、最大强化率(ER)等参数。结果64例良性肿块中有48例的动态增强曲线为A型,25例恶性肿块中有17例的动态增强曲线为C型。良、恶性肿块总体比较,良性肿块的Tpeak值大于恶性肿块(P<0.01),WR和Slope值低于恶性肿块(P<0.01),ER值两者差异无统计学意义(P>0.05)。泪腺区、肌锥外间隙及肌锥内、外间隙的良性肿块的Tpeak值均大于恶性肿块(P<0.05),Slope、WR值均低于恶性肿块(P<0.05)。肌锥内间隙良、恶性肿块间差异无统计学意义(P>0.05)。结论动态增强扫描有助于眼眶良、恶性肿块的诊断和鉴别诊断。

The Diagnostic Value of Dynamic Contrast-Enhanced MRI in Detection of Orbital Masses

Objective To evaluate the diagnostic value of dynamic contrast-enhanced MRI(DCE-MRI) in the differentiation on benign and malignant masses in the orbit.Methods Eighty-nine patients with orbital masses confirmed by pathology were studied.The study group consisted of 54 women and 35 men.After conventional MR imaging,dynamic contrast-enhanced MR imaging was performed using a 3D fast spoiled gradient echo sequence.Calculated values included time to peak(Tpeak),washout ratio(WR),Slope and enhancement ratio(ER),The types of the time-intensity curves(TICs) were studied.Tpeak,WR,slope and ER were calculated preoperatively.Results The TIC of 48 of 64 benign masses were type A,while 17 of 25 malignant masses were type C.Benign masses of the orbit had a significantly longer Tpeak(P<0.01),slower WR(P<0.05) and lower slope(P<0.01) than malignant masses.No significant differences in ER(P>0.05) was seen between benign and malignant masses.Of masses of lacrimal gland region,within the extraconal space,and involving both the extra and intra-conal spaces,There was longer Tpeak(P<0.05),slower WR(P<0.05) and lower slope(P<0.05) in benign masses compared with malignant masses.There was no significant differences between the benign and malignant tumors within the intraconal space(P>0.05).Conclusion DCE-MRI is useful in the diagnosis and differential diagnosis of benign and malignant masses of the orbit.