Hawighorst H, Knapstein P G, Schaeffer U, Knopp M V, Brix G, Hoffmann U, Zuna I, Essig M, van Kaick G
Department of Radiological Diagnosis and Therapy, German Cancer Research Center, Heidelberg, Germany, USA.
AJR Am J Roentgenol. 1996 Feb;166(2):401-8. doi: 10.2214/ajr.166.2.8553955.
Dynamic MR image series were analyzed with a pharmacokinetic two-compartment model. To preserve the spatial resolution of the dynamic MR images, the pharmacokinetic parameters were computed pixel by pixel, color coded, and superimposed on conventional MR images (pharmacokinetic mapping). The efficacies of pharmacokinetic mapping and conventional MR imaging in distinguishing between recurrent tumors and benign conditions in patients who have pelvic lesions after treatment of cervical carcinoma were compared.
Twenty-one women with 24 suspected pelvic lesions and a history of treated cervical carcinoma (stages IB-IIIA) were included in this study. Patients had been treated before MR imaging with surgery or irradiation alone (eight patients) or a combination of the two (13 patients). Patients were referred because of our findings from CT examinations and/or clinical examinations. Of 24 suspected lesions, 17 were histologically verified as tumor recurrences and seven were classified as benign masses (histologically diagnosed as fibrosis and granulation tissue). T1- and T2-weighted spin-echo images were interpreted by three observers. During and after constant-rate infusion of gadopentetate dimeglumine, the kinetics of lesion response were determined with a strongly T1-weighted saturation recovery turbo-fast low-angle shot sequence. The signal-time curves for the suspected lesions were analyzed within the framework of a pharmacokinetic two-compartment model and displayed as color-coded images. The calculated pharmacokinetic parameters (amplitude [A] and tissue distribution time [t21]) were evaluated retrospectively to obtain optimal threshold values for differentiating malignant lesions from benign lesions.
Analysis of the pharmacokinetic mapping data showed significantly shorter (p < .005) and stronger (p < .001) contrast medium enhancement of malignant lesions (t21, 24 sec; A, 1.5 arbitrary units) than of benign lesions (t21, 65 sec; A, 0.7), resulting in a sensitivity of 100%, a specificity of 88%, and an accuracy of 96%. Interpretation of the lesions on conventional T2-weighted MR images resulted in a sensitivity of 90%, a specificity of 38%, and an accuracy of 74%.
Analysis of color-coded pharmacokinetic maps is more effective than conventional MR imaging in distinguishing between malignant and benign conditions in patients who have pelvic lesions after treatment of cervical carcinoma.
采用药代动力学双室模型分析动态磁共振图像序列。为保留动态磁共振图像的空间分辨率，逐像素计算药代动力学参数，进行颜色编码，并叠加在传统磁共振图像上（药代动力学图谱）。比较药代动力学图谱和传统磁共振成像在鉴别宫颈癌治疗后盆腔病变患者的复发性肿瘤与良性病变方面的效能。
本研究纳入21例患有24处疑似盆腔病变且有宫颈癌治疗史（IB-IIIA期）的女性。患者在磁共振成像前已接受单独手术或放疗（8例）或两者联合治疗（13例）。患者因CT检查和/或临床检查结果而被转诊。24处疑似病变中，17处经组织学证实为肿瘤复发，7处被分类为良性肿块（组织学诊断为纤维化和肉芽组织）。由三名观察者解读T1加权和T2加权自旋回波图像。在恒速输注钆喷酸葡胺期间及之后，采用强T1加权饱和恢复快速低角度激发序列测定病变反应的动力学。在药代动力学双室模型框架内分析疑似病变的信号-时间曲线，并显示为颜色编码图像。回顾性评估计算得到的药代动力学参数（幅度[A]和组织分布时间[t21]），以获得区分恶性病变与良性病变的最佳阈值。
药代动力学图谱数据分析显示，恶性病变（t21，24秒；A，1.5任意单位）的对比剂增强明显短于（p <.005）且强于（p <.001）良性病变（t21，65秒；A，0.7），灵敏度为100%，特异性为88%，准确率为96%。对传统T2加权磁共振图像上病变的解读，灵敏度为90%，特异性为38%，准确率为74%。
在鉴别宫颈癌治疗后盆腔病变患者的恶性与良性病变方面，颜色编码药代动力学图谱分析比传统磁共振成像更有效。
