Analysis of the effect of percutaneous vertebroplasty combined with (125)I seed implantation in the treatment of spinal metastatic epidural spinal cord compression

Abstract

Objective: To investigate the clinical efficacy of percutaneous vertebroplasty (PVP) combined with iodine-125 ((125)I) seed brachytherapy in the treatment of spinal metastatic epidural spinal cord compression (MESCC) and toassess the changes inthe grade of epidural spinal cord compression (ESCC) by magnetic resonance imaging (MRI). Methods: A total of 37 MESCC patients treated with PVP combined with (125)I seed brachytherapy in the interventional and vascular surgery department of Zhongda Hospital affiliated to Southeast University from January 2014 to June 2019 were retrospectively analyzed, including 23 cases of bilateral lower limbs paralysis. Total diseased vertebrae are 39 segments. Visual analogue scale (VAS) and paralysis of lower extremities were evaluated regularly before and after treatment, and VAS values at different follow-up time points were compared. At the same time, MRI was used to evaluate the changes of ESCC grade in the spinal canal and calculate the local lesion efficiency after operation. The postoperative local lesion efficiency at different follow-up times was compared. Results: PVP combined with (125)I seed implantation in all diseased vertebral bodies was successful. The average injection volume of polymethylmethacrylate (PMMA) was (3.2±1.3) ml/segment, the average number of (125)I seed implanted was (25.0±8.6) seeds/segment and the average radiation dose was (15.0±5.1) mCi/segment. The VAS before operation was 8.5, and postoperative VAS were respectively 3.6±1.3, 3.8±1.5, 3.4±1.4, 5.5±1.0, 5.9±1.4 at 5 days, 1 month, 3 months, 6 months, and 1 year after operation. The differences between all follow-up time points and preoperative VAS values were statistically significant (all P<0.001). Compared with 5 days, 1 month and 3 months after operation, VAS increased significantly at 6 months and 1 year after operation, and the difference was statistically significant (all P<0.001); there was no significant difference between the VAS value at 6 months after operation and 1 year after operation (P=0.405). At a follow-up of 3 months, 22 of 23 patients with paralysis of bilateral lower limbs regained the functions of autonomous walking and voiding; the effective rates of MESCC local lesions evaluated by MRI at 1 month, 3 months, 6 months, and>1 year were 89.7%, 91.9%, 90.6%, and 94.7%, respectively, and there was no statistically significant differences among those follow-up time points (all P>0.05). Conclusions: PVP combined with (125)I seed brachytherapy in the treatment of MESCC has significant improvement in immediate pain relief and spinal cord function. After combined treatment, MRI showed that the tumors around the spinal cord regressed dramatically, which could considerably reduce the MESCC grade and remain stable for a long time.