First Experience of Intra-Operative Radiation Therapy (IORT) during Kyphoplasty in Patients Diagnosed with Spinal Metastasis in Iran

Object: Based on previous studies, 30 to 40% of cancer patients are diagnosed with bone metastasis. Median Overall Survival (OS) of patients who are diagnosed with spinal metastasis (vertebral structures) is about 7 to 9 months which with recent progresses in oncologic and radiotherapy treatment modalities, their prognosis is slightly developed. In this study, authors plan to evaluate the effects of Intra-operative Radiation Therapy (IORT) in patients who are candidate for Kyphoplasty procedure. Methods: In this study, we have included patients who are diagnosed with spinal metastasis with radiological and histopathological confirmation. From July 2017 to December 2018, we have included 9 patients who fulfilled our predefined inclusion and exclusion criteria into our case-series study performed on Shohada Tajrish Hospital. Patients underwent radiotherapy during Kyphoplasty by our IORT device INTRABEAM (Carl Zeiss AG, Germany) as “Kypho-IORT’ procedure. We have evaluated these patients in post-operative period, as well as on 2 weeks, 1 month, 2 months and 6 months on post-operative period as our follow-up plan. Results: In this study, 9 patients (5 males and 4 females) with mean age of 68 years with spinal metastasis from breast (4 cases), prostate (2 cases), lung (2 cases) and gastrointestinal tract (1 case), underwent Kypho-IORT for 15 vertebrae levels with individualized radiation dose and interval. In postoperative follow-up period, patients exhibit pain relief (in 78%) assessed by Visual Assessment Score (VAS) and improvement in their Quality of Life (QoL). No major complications including new neurological deficit, major cement leak and embolic disorders were encountered during the study; however, minor cement leak encountered in 4 cases, and 2 patients have expired during follow up period; however, other patients are still alive and under follow-up with mean OS of 10 months. Conclusion: This study is the first experience of evaluation of IORT effects during Kyphoplasty in Iran, in patients diagnosed with spinal metastasis with poor prognosis, to improve their quality of life, local control rate and their OS. This study could be considered as one of the pioneers in continuing the evaluation of Kypho-IORT as a novel technique in these group of patients.

Clinical Outcome and Histological Findings After Induced Leakage of PMMA Loaded With Methotrexate and Cisplatin During Vertebroplasty: Experimental Model in Pigs

Study Design: Animal experimental model. Objective: To study the clinical behavior and histological changes in the spinal cord, nerve roots and perivertebral muscles of the spine after induced leakage of polymethylmethacrylate (PMMA) loaded with antiblastic drugs during vertebroplasty in an animal model of pigs. Methods: We performed vertebroplasty on 25 pigs. The animals were divided into 3 groups: vertebroplasty with PMMA alone (control group), vertebroplasty with PMMA loaded with methotrexate (MTX) and vertebroplasty with PMMA loaded with cisplatin (CYS). At 2 vertebral levels, epidural and prevertebral, massive cement leaks were induced. Animals were evaluated daily. Two weeks later, the pigs were sacrificed, and the tissues that came in contact with the cement were analyzed. Results: The clinical results for each of the groups were reported. The control group had no clinical alterations. In the MTX group, 2 pigs died before 1 week due to pneumonitis. In the CYS group, 4 animals had motor impairment, and 3 of the 4 had paraplegia. The histological results were as follows: the control and MTX groups showed synovial metaplasia, inflammatory reaction, crystal deposits, and giant cell reaction in the dura mater and muscle and all the animals in the CYS group had spinal cord and muscular necrosis. Conclusions: Massive cement leak after vertebroplasty with PMMA loaded with cisplatin is extremely toxic to the spinal cord and muscles around the spine. Therefore, its use cannot be recommended for the treatment of vertebral metastases. Using PMMA loaded with methotrexate seems to be a safe procedure, but further research is needed.

Stent screw–assisted internal fixation (SAIF): clinical report of a novel approach to stabilizing and internally fixating vertebrae destroyed by malignancy

OBJECTIVESevere lytic cancerous lesions of the spine are associated with significant morbidity and treatment challenges. Stabilization and restoration of the axial load capability of the vertebral body (VB) are important to prevent or arrest vertebral collapse. Percutaneous stent screw–assisted internal fixation (SAIF), which anchors a VB stent/cement complex with pedicular screws to the posterior vertebral elements, is a minimally invasive, image-guided, 360° internal fixation technique that can be utilized in this patient cohort. The purpose of this study was to assess the feasibility, safety, and stabilization efficacy of VB reconstruction via the SAIF technique in a cohort of patients with extensive lytic vertebral lesions, who were considered to have an unstable or potentially unstable spine according to the Spinal Instability Neoplastic Score (SINS).METHODSThis study was a retrospective assessment of a prospectively maintained database of a consecutive series of patients with neoplastic extensive extracompartmental osteolysis (Tomita type 4–6) of the VB treated with the SAIF technique. VB reconstruction was assessed on postprocedure plain radiographs and CT by two independent raters. Technical and clinical complications were recorded. Clinical and imaging follow-ups were assessed.RESULTSThirty-five patients with extensive osteolytic metastatic lesions of the VB underwent 36 SAIF procedures. SAIF was performed as a stand-alone procedure in 31/36 cases and was associated with posterior surgical fixation in 5/36 (4/5 with decompressive laminectomy). In 1 case an epidural cement leak required surgical decompression. VB reconstruction was categorized as satisfactory (excellent or good rating) by the two raters in 34/36 cases (94.5%) with an interrater reliability of 94.4% (Cohen’s kappa of 0.8). Follow-up, ranging from 1 to 30 months, was available for 30/36 levels. Long-term follow-up (6–30 months, mean 11.5 months) was available for 16/36 levels. Stability during follow-up was noted in 29/30 cases.CONCLUSIONSSAIF provides 360° nonfusion internal fixation that stabilizes the VB in patients with extensive lytic lesions that would otherwise be challenging to treat.

Surgical Trend Analysis for Use of Cement Augmented Pedicle Screws in Osteoporosis of Spine: A Systematic Review (2000-2017)

Study Design: Systematic review. Objectives: (1) Study indications for cement-augmented pedicle screws (CAPS) in patients with osteoporosis. Have they changed over the years (2000-2017)? Are there any differences in usage of CAPS based on the geographical region? (2) What were the outcome of the studies? (3) What are the complications associated with this technique? Methods: Electronic database and reference list of desired articles were searched from the database (2000-2017). Articles were selected discussing indications, clinical and radiological outcomes, and complications in cases of preexistent osteoporosis treated surgically using CAPS. Results: Seventeen studies were identified; 3 were comparative studies and had a control arm (cemented vs noncemented screws). Most studies originated from Europe (10) or Asia (7). Painful vertebral fracture with or without neurological deficit, Kummell’s lesion, deformity and failure to respond to conservative treatment are the common indications for cement augmentation. Visual analogue scale score was the most commonly used to assess pain and average improvement after surgery was 6.1. Average improvement in kyphosis was 13.21° and average loss of correction at the end of the study was 3°. Cement leak was the most common complication observed and pulmonary cement embolism was the most dreaded complication. Nevertheless, majority of cement leaks discussed in studies were asymptomatic. Conclusion: CAPS are being increasingly used in osteoporotic spine. Pain scores, functional quality of life, and neurological function indices were studied. CAPS improved anchorage in osteoporotic vertebra and helped improve/maintain clinical and radiological improvement. Common risks of cement leak were observed.

Impact of the quantity of intradiscal cement leak on the progression of intervertebral disc degeneration

Introduction We aim to assess the impact of the quantity of intradiscal cement leak during kyphoplasty on the rate of progression of degenerative changes in the affected disc. Methods Of 316 kyphoplasty procedures, we identified 32 episodes of intradiscal cement leak in 26 patients. The quantity of cement leaked was graded from I to IV. Disc degenerative changes were assessed at presentation and follow-up using radiographical scoring and magnetic resonance imaging (MRI) grading systems. Data for low-grade leaks (grade I) were compared with the medium- and high-grade leaks (grades II–IV) using a chi-squared test. Results Median follow-up radiographic and MRI assessments were made at 18 and 21 months, respectively. Medium- and high-grade leaks were associated with a significantly higher radiographic disc degeneration scores compared with low-grade leaks (P = 0.04295) but no difference was found in MRI disc degeneration grades and in adjacent vertebral fracture rates. Conclusions Our findings indicate that the quantity of cement leaking into the disc space significantly influences the rate of progression of disc degeneration.