Predictive value of pedicle involvement with MRI in spine metastases

// Wang Mi Liu 1, * , Rong Xing 1, * , Chong Bian 1 , Yun Liang 1 , Libo Jiang 1 , Chen Qian 1 , Jian Dong 1 1 Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China * These authors have contributed equally to this work Correspondence to: Jian Dong, email: dong.jian@zs-hospital.sh.cn Keywords: MRI, spine metastases, pedicle Received: February 19, 2016      Accepted: June 17, 2016      Published: July 28, 2016 ABSTRACT Objectives: The study aimed to retrospectively evaluate the accuracy and value of magnetic resonance imaging (MRI) in predicting pedicle involvement for patients with spine metastases. Methods: Forty-five patients with a vertebral metastasis encroaching at least one pedicle were studied using MRI before surgery and regularly after surgery. Patients were categorized on the basis of their numbers of pedicle involvement (Group 1: one pedicle was involved, n = 23; Group 2: two pedicles were involved, n = 22). The diagnostic accuracy was calculated, and comparisons of intraoperative blood loss and recurrence rate between the two groups were performed. Results: The overall performance of MRI in predicting the pedicle involvement was as follows: accuracy, 94.4%; sensitivity, 95.5%; and specificity, 91.3%. Less intraoperative blood loss was observed for Group 1 compared with Group 2 (1,661 ± 672 ml and 2,173 ± 790 ml, respectively, P = 0.024). Tumor relapse occurred in 8.7% (2/23) of Group 1 and in 22.7% (5/22) of Group 2 with median recurrence free survival time 14 and 9 months, respectively. Conclusions: MRI is a reliable approach to assess pedicle involvement. It has potential for use in the evaluation of the clinical characteristics of patients with spine metastases.