Palliative pain relief and safety of percutaneous radiofrequency ablation combined with cement injection for bone metastasis.

PURPOSE: To investigate the pain relief effect and safety of percutaneous radiofrequency ablation (RFA) with a multitined electrode combined with cement injection in patients with painful metastatic bone tumors. MATERIALS AND METHODS: Sixteen patients with 34 osteolytic metastatic lesions were treated with RFA including 4 males and 12 females (age range 54-84). Thirteen patients with spinal metastases received additional cement injection. Medical imaging, a visual analog scale (VAS) and the EORTC QLQ-C30 were performed to evaluate the metastatic lesion, pain and quality of life, respectively, before and after RFA and at follow-ups. RESULTS: The RFA and/or vertebroplasty with cement injection were successful in all patients (100%). Except for one patient who had cement leakage, no intraprocedural complications occurred. After RFA, severe refractory pain was greatly relieved in all patients, with pretreatment VAS score of 8.1 ± 1.4 significantly reduced to 5.5 ± 1.1 at 24 h, 2.8 ± 0.6 at 1 week and 1.4 ± 0.8 at 6 months (P < 0.01). The EORTC QLQ-C30 scale at 1 month demonstrated significant improvement (P < 0.05) in the physical (P = 0.03) and emotion function (P = 0.003), global health status (P = 0.002), pain (P = 0.001) and insomnia (P = 0.002). The analgesics were reduced after the procedure and stopped 2 months later in all patients, with greatly improved quality of life and no apparent pain. Followed up for 6-12 months, all patients remained alive with no recurrence of pain. Palliative pain relief and safety of percutaneous radiofrequency ablation combined with cement injection for bone metastasis. CONCLUSION: RFA with or without bone cement is safe and effective in the palliative treatment of pain caused by metastatic bone tumors.

Prophylactic abdominal aortic balloon occlusion: An effective method of controlling hemorrhage in patients with placenta previa or accreta.

Postpartum hemorrhage is considered to be a serious complication in patients with pernicious placenta. Approaches employing abdominal aortic balloon occlusion to control hemorrhage are extremely effective for such patients. The present study analyzed 9 patients with pernicious placenta previa in a single hospital from June 2016 to November 2017. Prior to cesarean hysterectomy, an abdominal aortic balloon catheter was placed in all patients. The balloon was inflated and evacuated alternately using saline following delivery of the fetal head. The X-ray dose, bleeding volume and complications during the procedure were observed. Balloon catheterization was successfully performed in all 9 patients. The dose of X-rays ranged from 15.8 to 24.5 mGy, with a mean of 19.3±2.7 mGy; the volume of blood loss ranged from 50 to 4,000 ml, with a mean of ~1,800 ml. Uterine artery embolization was successfully performed in 2 cases due to bleeding following the cesarean hysterectomy, and every uterus was retained. Abdominal aortic balloon occlusion can effectively reduce the amount of bleeding during cesarean hysterectomy in patients with pernicious placenta previa. This may serve as technical support for patients in whom retention of the uterus is expected. However, it is necessary to identify any abnormal uterine tissue above the level of the renal artery in order to avoid ineffective balloon occlusion.

Thermal effect of percutaneous radiofrequency ablation with a clustered electrode for vertebral tumors: In vitro and vivo experiments and clinical application.

PURPOSE: To investigate effects and heat distribution of radiofrequency ablation (RFA) on vertebral tumors in vitro and in vivo swine experiments and its clinical application. MATERIALS AND METHODS: RFA was performed on the swine spine in vitro and in vivo for 20 min at 90 °C at the electrode tip, and the temperature at the electrode tip and surrounding tissues were recorded. Clinical application of ablation combined with vertebroplasty was subsequently performed in 4 patients with spinal tumors. RESULTS: In the in vitro study, the mean temperature at the front and ventral wall of the spinal canal was 50.8 °C and 43.6 °C, respectively, at 20 mm significantly greater than 37.7 °C and 33.7 ± 1.7 °C, respectively, at 10 mm ablation depth. The coagulative necrosis area was significantly (P < 0.0001) greater at 20 mm depth than at 10 mm depth (mean 17.0 × 20.7 mm2 vs. 14.2 × 16.6 mm2). In the in vivo experiment, the local temperature increased significantly (P < 0.05) from around 36 °C before ablation to over 41 °C at 20 min after ablation, with the temperature at the electrode tip (90.4 °C) and within the vertebral body (67.0 °C) significantly (P < 0.05) greater than at the posterior (41.9 °C) and lateral wall (41.8 °C). From 2 to 5 weeks, bone remodeling began. Clinically, all four patients had successful RFA and vertebroplasty, with no neurological deficits. The pain scores were significanlty (P < 0.05) improved before (4.5-10, mean 8.0) compared with at four weeks (0-1.8, mean 1.8). CONCLUSION: The clustered electrode can be efficiently and safely applied in the treatment of spinal tumors without damaging the spinal cord and adjacent nerves by heat distribution.

In vivo effects of radiofrequency ablation on long bones and the repair process in swine models.

PURPOSE: To investigate in vivo effect of radiofrequency ablation (RFA) on swine long bones and the repair process. MATERIALS AND METHODS: RFA was performed in six swine at the end and middle part of the tibia or femur. After RFA, radiological examinations were performed, and the swine were killed immediately and at different time points post-RFA for histopathological examination. RESULTS: All swine had successful RFA. The RFA-induced elliptical necrotic area ranged from 3.81-5.24 cm2 (mean 4.08 ± 0.73 cm2) at the bone end but 5.60-8.98 cm2 (mean 7.58 ± 1.41) at the middle part immediately after RFA until 10 days, with the necrosis area significantly smaller (P = 0.000) at the end than at the middle. RFA only damaged the cortical bone slightly (0.01 cm thick) with no damage to the soft tissues outside the compact bone at both the end and middle. Surrounding the elliptic pale zone of coagulative necrosis was a narrow brown band of hemorrhage and inflammatory exudate. From day 10 until week 12, tissue proliferation and repair became increasingly apparent, with proliferated granulation, fibrous tissue, and fresh and mature bone trabecula. CONCLUSION: RFA can quickly and effectively destroy the cancellous bone tissue without affecting the cortical bone and activate bone remodeling.

Dynamic expression of molecules that control limb muscle development including Fhl1 in hind limbs of different gestational age.

Muscle abnormality could be a key reason for congenital clubfoot (CCF) deformity, which manifests itself during fetal development. FHL1 down-regulated expression is involved in the formation of skeletal muscle abnormalities in CCF and FHL1 gene mutations contribute to the development of some kinds of myopathies. Therefore, detecting dynamic expression of Fhl1 and other molecules (Hgf, MyoD1, Myogenin, and Myh4) that control limb muscle development in hind limbs of different gestational age will provide a foundation for further research on the molecular mechanism involves in the myopathies or CCF. The dynamic gene expression levels of Fhl1, Hgf, MyoD1, Myogenin, and Myh4 in the lower limbs of E16, E17, E19, and E20 rat embryos were examined by real-time RT-PCR. Immunofluorescence was used to detect formation of specific muscle fibers (fast or slow fibers) in distal E17 hind limbs. The expression levels of Fhl1, Hgf, MyoD1, Myogenin, and Myh4 were varying in hind limbs of different gestational age. Real-time PCR results showed that all the genes that control skeletal muscle development except for Fhl1 exhibited a peak in E17 lower limbs. Immunofluorescence results showed obviously positive fast-myosin in the distal E17 lower limbs and meanwhile slow-myosin had no apparently signals. E17 was a critical time point for terminal skeletal muscle differentiation in the lower limbs of rat embryos.