Enhancement of the immune response to residual intrahepatic tumor tissue by laser-induced thermotherapy (LITT) compared to hepatic resection

BACKGROUND AND OBJECTIVES: In contrast to hepatic resection, thermally destroyed autologous tumor cells remain in situ after laser-induced thermotherapy (LITT). The aim of the study was to evaluate the effect of LITT and hepatic resection on the immune response to residual intrahepatic tumor tissue and the growth of untreated liver metastases. STUDY DESIGN/MATERIALS AND METHODS: Two independent adenocarcinomas (CC531) were implanted into 60 WAG rats, one in the right (control tumor) and one in the left liver lobe (treated tumor). The left lobe tumor was treated either by LITT or partial hepatectomy. The control tumor was submitted to further investigation 24 hours, 96 hours, 7 days, and 10 days after treatment. RESULTS: Ten days after treatment, control tumor volumes were 296+/-46 mm_ after LITT and 1,181+/-192 mm_, 1,387+/-200 mm_ after hepatic resection and no treatment, respectively (P<0.001). Peritoneal tumor spread was detected in 4/20 cases after LITT and in 17/20 cases after hepatic resection. Expression of CD8, B7-2 (CD86), and to lesser extent MHCII, LFA1 (CD11a), and ICAM1 (CD54), was significantly enhanced at the invasion front of control tumors after LITT compared to hepatic resection. CONCLUSIONS: Our results suggest that LITT increases the immune response against untreated intrahepatic tumor tissue, which can lead to reduced tumor growth.     

肿瘤姑息切除结合骨水泥强化治疗多发性胸腰椎转移性肿瘤的一年期临床观察

【摘要】〓目的〓探讨对于已经出现脊髓或神经根压迫的多发性胸腰椎转移瘤手术治疗的方法和效果。方法〓采用回顾性研究,对2013~2015年本院收治有完整随访资料的19例多发性胸腰椎转移瘤并出现神经功能受损手术患者,采用后路肿瘤姑息切除椎弓根螺钉固定结合骨水泥充填椎体强化治疗,术后随访1年期内,定期观察术后患者生存质量(包括疼痛、睡眠、食欲)改善程度和神经功能恢复程度。结果〓全组19例患者术后生存质量(疼痛、食欲、睡眠)获得显著改善(与术前比较P<0.01),术后三月约78.9%的患者神经功能获得至少Frankel 1级以上恢复。脊椎稳定性得到加强,在1年随访期内未见内固定松动移位。1例患者在随访期内死亡,2例患者出现局部复发(10.53%)。结论〓对于已经出现脊髓或神经根压迫的多发性胸腰椎转移瘤患者,肿瘤姑息切除结合骨水泥注射强化治疗可以在近期内有效改善晚期肿瘤患者神经功能恢复以及提高患者的生存质量。     

Continuous changes in the optical properties of liver tissue during laser-induced interstitial thermotherapy

BACKGROUND AND OBJECTIVE: Laser-induced thermotherapy (LITT) is a promising treatment for irresectable liver tumors. To predict the effects of laser applications and to optimize treatment planning in LITT, it is essential to gain knowledge about light distribution in tissue, tissue optical properties (absorption, scattering, anisotropy, penetration depth), and their continuous changes during therapy. STUDY DESIGN/MATERIALS AND METHODS: Measurements of optical properties were performed with a double integrating-sphere system and a laser diode (830 nm). Porcine liver tissue samples were examined in a native state (35 degrees C) and after exposure to different temperatures (45 degrees C to 80 degrees C). RESULTS: Rising temperature was accompanied by a decrease in the absorption coefficient and anisotropy factor and an increase in the scattering coefficient. These changes were only significant in the temperature range of 50 degrees to 65 degrees C (P < 0.01). The optical penetration depth decreased from 3.1mm in the native state to 1.7mm at 65 degrees C (P < 0.01). Above 65 degrees, there was no significant change in the tissue optical properties. CONCLUSIONS: The optical properties of liver tissue change significantly under the influence of tissue heating, resulting in a decreased optical penetration depth. These changes occur mainly in the temperature range of 50 degrees C to 65 degrees C, corresponding to protein denaturation. To ensure a safe and effective procedure, an adjustment of the laser power to the actual penetration depth is recommended during therapy.     

Laser induced thermotherapy (LITT) of experimental liver metastasis-detection of residual tumors using Gd-DTPA enhanced MRI

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the accuracy of Gd-DTPA MRI in the detection of recurrent tumor after laserinduced thermotherapy (LITT) of experimental liver metastases. STUDY DESIGN/MATERIALS AND METHODS: LITT was performed at different energy levels in VX-2 tumor-bearing rabbits (n = 80). MRI and histology were placed at 0, 24, 96 hours, and 14 days. Signal intensities were calculated of the transition between thermally damaged and undamaged tissue (transition zone = TZ) and of the surrounding tissue (reference zone = RZ). RESULTS: Tumor recurrence was seen in 47 animals. At 24 hours sensitivity, specificity and accuracy was 92, 100, and 95% in TZ and 23, 100, and 50% in RZ. At 14 days sensitivity, specificity and accuracy was 100, 11, and 60% in TZ and 100, 89, and 95% in RZ. CONCLUSIONS: Recurrence is best excluded in TZ at 24 hour and in RZ at 14 day with an accuracy up to 95%.     

Colorectal tumors and hepatic metastases differ in their optical properties-relevance for dosimetry in laser-induced interstitial thermotherapy

BACKGROUND AND OBJECTIVES: The therapeutic application of laser light is a promising alternative to surgical resection of colorectal liver metastases. The extent of tumor destruction achieved by this strategy depends primarily on light distribution in the target tissue. Knowledge about optical properties is necessary to predict light distribution in the tissue for careful irradiation planning. The aim of this study was to compare the optical behavior of healthy colon tissue with that of colorectal carcinomas and their hepatic metastases in the native and coagulated state in order to test the effect of malignant degeneration, metastasis, and thermal coagulation on optical parameters. MATERIALS AND METHODS: Ninety tissue samples were taken from patients with a colorectal carcinoma and concomitant liver metastases: healthy colon tissue (n = 30); colon carcinoma (n = 30); liver metastases (n = 30). Optical properties were measured according to the single integrating sphere principle in the native state and after thermal coagulation in the wavelength range of 800-1,100 nm and analyzed by inverse Monte Carlo simulation. RESULTS: The highest optical penetration depth for all tissue types was obtained at the end of the spectral range investigated. The highest penetration depths of 4.13 mm (healthy colon), 7.47 mm (colon carcinoma tissue), and 4.08 (liver metastases) were at 1,060 nm, although the values decreased significantly after thermal coagulation. Comparing healthy colon-to-colon carcinoma always revealed a significantly lower absorption and scattering coefficient in the tumor tissue. This resulted in a higher optical penetration depth of the laser light in the colon carcinoma tissue (P < 0.05). A direct comparison disclosed no agreement between the optical properties of the primary tumor and the liver metastases. In the native state, colon carcinoma tissue had a lower scattering coefficient (P < 0.05), higher anisotropy factor, and optical penetration depth than liver metastases (P < 0.05). The absorption coefficient did not differ significantly. The differences in the native state were equalized by tissue coagulation. CONCLUSIONS: Colon carcinoma tissue has a higher optical penetration depth than healthy colon tissue, which speaks in favor of tumor selectivity for interstitial laser application, since large treatment volumes can be obtained in the tumor. The lack of agreement between primary tumors and their concomitant liver metastases indicates a modification of optical behavior through metastasis. Thermal coagulation of tissue leads to changes in the optical properties, which are clearly less pronounced in carcinoma tissue. The data obtained in this study clearly show that an individual irradiation schedule is necessary for effective and safe dosimetry in laser-induced thermotherapy (LITT).     

Effectivity of laser-induced thermotherapy: in vivo comparison of arterial microembolization and complete hepatic inflow occlusion

BACKGROUND AND OBJECTIVES: Laser-induced thermotherapy (LITT) is a promising method for local treatment of liver metastases. The aim of this study was to compare the effect of LITT on lesion size when combined with hepatic arterial microembolization or complete hepatic blood flow occlusion. STUDY DESIGN/MATERIALS AND METHODS: In a porcine liver model, LITT (30 W 15 minutes) was performed with either normal (n = 12), partially interrupted (arterial microembolization via a hepatic artery catheter n = 12) or completely interrupted hepatic perfusion (Pringle's maneuver, n = 12). LITT lesions were macro- and microscopically assessed after liver dissection. RESULTS: Hepatic inflow occlusion led to a fourfold increase in lesion volume after arterial microembolization and a ninefold increase after complete interruption (6.3. cm3 vs. 27.1 cm3 vs. 58.8 cm3, P < 0.01). CONCLUSIONS: Interrupting hepatic perfusion significantly increases lesion volumes in LITT. This beneficial effect can also be achieved in the percutaneous application mode by LITT combined with arterial microembolization via a hepatic artery catheter.     

明胶海绵在经皮椎体成形术中预防骨水泥渗漏的作用研究

目的 观察明胶海绵在经皮椎体成形术(percutaneous vertebroplasty,PVP)中预防骨水泥渗漏的作用效果.方法 回顾性分析2014年6月至2015年12月于我院行PVP治疗伴椎体前壁破损的骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCF)病人72例,术中应用明胶海绵预先填塞椎体破损处的36例病人纳入明胶海绵组,未使用明胶海绵填塞的36例病人纳入常规组.收集并比较两组病人的疼痛视觉模拟量表(visual analogue scale,VAS)评分改善、椎体高度改善、Cobb角改善以及骨水泥渗漏率.结果 明胶海绵组未发生骨水泥渗漏,常规组发生6例(16.67%)骨水泥渗漏,两组间渗漏率的差异有统计学意义(χ2=4.546,P=0.033);明胶海绵组的VAS评分改善、椎体高度改善和Cobb角改善分别为(5.14±1.08)分、(8.70±3.64)mm、17.15°±6.81°,常规组的各项指标分别为(5.11±1.34)分、(8.69±4.31)mm、15.80° ±6.61°,两组间以上三项指标比较,差异均无统计学意义(P均>0.05).结论PVP治疗伴有椎体前壁破损的OVCF术中应用明胶海绵可以有效降低骨水泥的渗漏率,对骨水泥渗漏具有一定的预防作用.     

腹腔镜下微波消融剜除术治疗肾脏肿瘤的疗效分析

目的 探讨腹腔镜下微波消融肾肿瘤剜除术治疗肾脏肿瘤的疗效与安全性.方法 本组84例肾肿瘤患者,予以腹腔镜下辅助微波消融,尔后手术剜除肾肿瘤,记录术中出血量、手术时间,观察术中、术后并发症及疗效与安全性.结果 84例患者手术均顺利完成,术中均未阻断肾动脉,无术中大出血或中转开放手术,出血量为50~350 ml,手术时间为70~120 min.术后病理诊断为肾透明细胞癌60例,血管平滑肌脂肪瘤16例,嗜酸性细胞瘤4例,嫌色细胞癌2例,乳头状肾细胞癌2例.术中血管平滑肌脂肪瘤普遍出血较多.术后血管平滑肌脂肪瘤出血1例.全部病例随访12个月,无肿瘤复发、远处转移或死亡病例.结论 腹腔镜下微波消融肾肿瘤剜除术是一种安全有效的保留肾单位的手术方式,具有出血量少、手术时间短、术后并发症少等优点.     

A thoracic and lumbar spine injury severity classification based on neurologic function grade, spinal canal deformity, and spinal biomechanical stability

BACKGROUND CONTEXT: Current well regarded thoracic and lumbar spine injury classifications use mechanistic and anatomical categories, which do not directly rely on quantifiable management parameters. Their clinical usefulness is not optimal. PURPOSE: Formulate an injury severity based classification. STUDY DESIGN/SETTING: This retrospective investigation studied patients who suffered thoracic and lumbar spine injuries, and examined the following three quantifiable parameters: 1) neurologic function grade; 2) spinal canal deformity; 3) biomechanical stability. These parameters are the primary clinical indications for management decisions. PATIENT SAMPLE: One hundred twenty-six consecutive patients with spinal trauma admitted to a level 1 tertiary trauma center from January 1997 to November 2005 were enrolled in this study. OUTCOME MEASURES: Spine injury severity was independently scored on three parameters: 1) neurologic function impairment grade according to the modified Frankel grading method and the American Spinal Injury Association (ASIA) function scale; 2) spinal canal deformity from translation and intrusion, measured as percent canal cross-sectional area compromise; 3) failure of five possible biomechanical functions in Denis's three anatomic columns, and a sixth group of unstable deformities. All three columns contribute to tensile function. Only the anterior and middle columns provide compression load-bearing function. A combination of three or more column biomechanical function failure or an unstable deformity renders the injury unstable. METHODS: Five fellowship-trained spine surgeons from one institution took part in the study. Hospital medical records, including admission history and physical examination, discharge summary, and operative report (if surgery was performed), were examined for neurologic deficit. Plain radiographs, computed tomographic scans and magnetic resonance imaging were assessed for canal compromise and biomechanical function status. RESULTS: Injuries were located from T3 to L5, 58% of which were at the thoracolumbar junction (T11-L2). Neurologic impairment occurred in 45% (57/126) of patients, with 19 complete paraplegias (Frankel grade A). The average spinal canal cross-sectional area compromise was 56.1% in neurologically impaired and 14.2% for patients who where neurologically intact. The number of tensile element failure patients in neurologically impaired versus intact are as follow: tri-columns 22/4; two columns 16/8; one column 11/17; all columns intact 8/40. Load-bearing element failed in 55/57 neurologically impaired and 63/69 intact patients. Sixty-seven patients had spinal reconstructive surgery. Their average instability profile score was 4.4 out of 6, and canal compromise score was 3.3 out of 5. CONCLUSIONS: A clinically useful thoracic and lumbar spine injury classification should be based on parameters that are the primary indications for management decisions. The same parameters should be injury severity quantifiable as to guide treatment. In this study we introduced spinal canal deformity and column biomechanical functions as quantifiable parameters in thoracic and lumbar injury severity classification. Validation of this method is beyond the scope of this preliminary study.     

单纯椎板减压椎弓根螺钉内固定术与联合微波消融治疗脊柱转移瘤的疗效比较

目的:比较单纯椎板减压、椎弓根螺钉内固定术与联合应用病灶微波消融术治疗脊柱转移瘤的临床效果.方法:回顾性分析2017年1月～2020年1月四川大学华西医院及四川省第四人民医院收治的69例脊柱转移瘤伴病理性骨折患者的临床资料,男41例,女28例,年龄27～71岁(52.8±9.7岁),单椎体受累43例,两个及以上椎体受累...     

Radiofrequency ablation of primary and metastatic liver tumors: a critical review of the literature

BACKGROUND: Surgical resection is the treatment of choice for hepatic tumors; however, for various reasons, the vast majority of patients are not operative candidates. As a result, several local ablative therapies have emerged as alternatives to resection or as adjuncts in total oncologic care. Presently, the most widely employed liver-directed treatment is radiofrequency thermal ablation. METHODS: To define the current status of radiofrequency ablation (RFA), the authors reviewed available safety and efficacy data from select studies on RFA. A MEDLINE search was performed using the keywords "tumor type" + "radiofrequency ablation" + "survival." Only those studies containing long-term survival data on greater than 50 patients were included in this analysis. CONCLUSIONS: Although RFA has been readily adopted into treatment paradigms, more rigorous trials are needed to solidify its place in the armamentarium of therapeutic strategies for hepatic malignancy.     

A 3D finite element model of prophylactic vertebroplasty in the metastatic spine: Vertebral stability and stress distribution on adjacent vertebrae

Background and Objective: Patients with metastatically compromised vertebra can experience pathologic fracture with relevant neurological complications. Vertebroplasty is a low cost procedure and it can potentially prevent neurologic impairment if performed at an early stage. The aim of this study is to evaluate the effects of prophylactic vertebroplasty on stability of the metastatic spine and analyze load distribution at adjacent vertebrae.

Setting: A 3D finite element model of two spinal motion segments (L3-L5) was developed. A central core of elements was selected in L4 vertebral body and material properties of a lytic metastasis and successively PMMA were assigned. The model was settled in order to simulate a non-osteoporotic spine and an osteoporotic spine.

Outcome Measures: Vertebral stability was assessed by the measurement of vertebral bulge (VB) and vertebral height (VH) on L4. Load transfer on adjacent vertebrae was evaluated by observing the distribution of the von Mises stress on L3 and L5 endplates.

Results: The metastasis increased VB by 424% and VH by 626%, while prophylactic vertebroplasty decreased VB and VH by 99% and 95%, respectively, when compared to the normal/non-metastatic model. Prophylactic vertebroplasty increased the average von Mises stress of L3 lower endplate by 1.33% in the non-osteoporotic spine, while it increased to 16% in the osteoporotic model.

Conclusions: Prophylactic vertebroplasty could represent an interesting option to improve vertebral strength of metastatically compromised spine without excessively increasing the stresses on adjacent vertebrae in non-osteoporotic spine.     

Laser-induced thermotherapy (LITT) elevates mRNA expression of connective tissue growth factor (CTGF) associated with reduced tumor growth of liver metastases compared to hepatic resection

BACKGROUND AND OBJECTIVES: Proliferation and synthesis of hepatocellular tissue after tissue damage are promoted by specific growth factors such as hepatic tissue growth factor (HGF) and connective growth factor (CTGF). Laser-induced thermotherapy (LITT) for the treatment of liver metastases is deemed to be a parenchyma-saving procedure compared to hepatic resection. The aim of this study was to compare the impact of LITT and hepatic resection on intrahepatic residual tumor tissue and expression levels of mRNA HGF/CTGF within liver and tumor tissue. STUDY DESIGN/MATERIALS AND METHODS: Two independent adenocarcinomas (CC531) were implanted into 75 WAG rats, one in the right (untreated tumor) and one in the left liver lobe (treated tumor). The left lobe tumor was treated either by LITT or partial hepatectomy. The control tumor was submitted to in-situ hybridization of HGF and CTGF 24-96 hours and 14 days after intervention. RESULTS: Volumes of the untreated tumors prior to intervention were 38+/-8 mm(3) in group I (laser), 39 +/- 7 mm(3) in group II (resection), and 42 +/- 12 mm(3) in group III (control) and did not differ significantly (P > 0.05). Fourteen days after the intervention the mean tumor+/-SEM volume of untreated tumor in group I (laser) [223 +/- 36] was smaller than in group II (resection) [1233.28 +/- 181.52; P < 0.001], and in group III (control) [978.92 +/- 87.57; P < 0.003]. Forty-eight hours after the intervention intrahepatic mRNA expression level of HGF in group II (resection) was almost twofold higher than in group I (laser) [7.2 +/- 1.0 c/mf vs. 3.9 +/- 0.4 c/mf; P<0.01]. Fourteen days after the intervention intrahepatic mRNA expression level of CTGF in group I (laser) was higher than in group II (resection) [13.89 +/- 0.77 c/mf vs. 9.09 +/- 0.78 c/mf; P < 0.003]. CONCLUSIONS: LITT leads to a decrease of residual tumor growth in comparison to hepatic resection. Accelerated tumor growth after hepatic resection is associated with higher mRNA level of HGF and reduced tumor growth after LITT with higher mRNA level of CTGF. The increased CTGF-mediated regulation of ECM may cause reduced residual tumor growth after LITT.     

Application of cement on strategic vertebrae in the treatment of the osteoporotic spine

Background Context

The application of pedicle screws with cement to strengthen the fixation of the osteoporotic spine has increasingly gained popularity. However, the technique has also led to an increase in cement-related complications.

Comparison of the effect of two different bone-targeted radiofrequency ablation (RFA) systems alone and in combination with percutaneous vertebroplasty (PVP) on the biomechanical stability of the metastatic spine

Introduction

Radiofrequency ablation (RFA) and percutaneous vertebroplasty (PVP) are used independently and in combination to treat metastatically involved vertebrae with the aim of relieving pain, reducing tumour burden and providing bony mechanical stabilization.

Purpose

The aim of this work was to characterize the effect of two bone-targeted RFA devices, alone and in combination with PVP, to improve strength and mechanical stability in vertebrae with osteolytic metastatic disease.

Methods

Simulated spinal metastases (n = 12) were treated with one of two bone-targeted RFA devices (bipolar cooled or bone coil RF electrodes), followed by PVP. Under axial compressive loading, spinal canal narrowing was measured in the intact specimen, after tumour simulation, post-RFA and post-PVP.

Results

RFA alone resulted in successful tumour shrinkage and cavitation, but further increased canal narrowing under loading. RFA combined with PVP significantly reduced posterior wall stability in samples where sufficient tumour shrinkage and cavitation were coupled with a pattern of cement deposition which extended to posterior vertebral body.

Conclusions

RFA combined with cement deposition in the posterior vertebral body demonstrates significantly more stable vertebrae under axial loading.

     

骨水泥分布对单侧经椎弓根穿刺治疗脊柱骨质疏松骨折临床效果的影响

目的:探讨单侧穿刺行椎体成形术(percutaneous vertebroplasty,PVP)治疗脊柱骨质疏松骨折骨水泥不同形态分布对临床疗效的影响。方法:回顾性选取2019年1月至2020年4月接受单侧穿刺PVP治疗的骨质疏松压缩性骨折患者66例(男16例,女50例),共83个椎体(胸椎45个,腰椎38个),其中单节段55例,双节段6例,3节段4例,4节段1例。纳入患者年龄60~93(76.83±8.65)岁,纳入患者发病后1~10 d就诊,术前均摄患椎正侧位X 线片、行 MRI 及骨密度仪检查明确诊断。按照术后X线中骨水泥的形态分为O形组(28例)和H形组(38例)。O形组骨水泥在术后X线患椎中呈聚集团块样分布;H形组骨水泥在术后X线患椎中呈弥散蜂窝状分布。收集两组患者骨水泥注射量;观察两组患者术中骨水泥渗漏及术后邻近椎体骨折的情况;比较两组患者术前及术后1 d、1个月、6个月、1年的视觉模拟评分(visual analogue scale,VAS)和术后1 d、6个月、1年的Oswestry功能障碍指数(Oswestry Disability Index,ODI);测量两组患者术前及术后1周、1年的患椎后凸角和患椎椎体前缘高度。结果:66例患者均完成了1年以上的随访,术后穿刺处均愈合良好,O形组和H形组术中分别出现1例和8例骨水泥的渗漏(P<0.05),但均无严重的并发症发生;术后1年的随访中两组均出现1例邻椎骨折(P>0.05)。两组骨水泥注射量差异无统计学意义(P>0.05)。术前、术后1 d、术后6个月、术后1年VAS评分 O形组分别为7.89±0.79、2.75±1.08、0.46±0.58、0.36±0.49,H形组分别为8.00±1.04、2.58±1.15、0.53±0.56、0.42±0.50,组间比较差异均无统计学意义(P>0.05);而术后1个月O形组和H形组VAS评分分别为0.96±0.58和1.18±0.83,差异有统计学意义(P<0.05)。术后1 d、6个月、1年的ODI评分O形组分别为12.43±3.78、10.00±2.46、8.43±1.50,H形组分别为12.11±3.68、9.53±2.35、8.32±1.51,组间比较差异无统计学意义(P>0.05)。术前、术后1周、术后1年患椎后凸角和前缘高度两组间比较差异均无统计学意义(P>0.05)。结论:无论骨水泥分分布形态是O形还是H形都能达到良好的临床效果,且预后效果相当。所以在进行单侧穿刺PVP手术时,不必为了达到患椎充分弥散的目的而刻意的增加穿刺针的穿刺角度,进而降低损伤重要结构、减少骨水泥渗漏等风险。     

MR弥散加权成像骨髓对比率与核素骨显像在脊柱转移瘤诊断中的价值

目的:对比MR弥散加权成像(DWI)骨髓对比率与核素骨显像在脊柱转移瘤诊断中的价值.方法:脊柱转移瘤患者40例,21例经骨穿刺检查、13例手术病理证实,其余6例经MRI、CT(或X线)、核素骨显像综合分析和随访证实为转移瘤.均进行b=500s/mm2的DWI扫描,在DWI图上描出感兴趣区(ROI),ROI应尽量包括最典型病灶并避开坏死部分,于病灶ROI上测量异常骨髓信号强度值为SIA,并与相邻椎体ROI上测量的正常骨髓信号强度值SIN比较,骨髓对比率的计算公式为(SIA-SIN)/SIN,测量得出脊柱转移瘤DWI上最典型病灶的骨髓对比率.观察DWI信号变化,测量表观弥散系数(ADC),计算骨髓对比率;并同时进行核素骨显像检查对比.结果:40例脊柱转移瘤患者中,DWI阳性共39例,其中颈椎5例,胸椎14例,腰椎20例;并在病变椎体上发现高信号病灶162个;核素骨显像检查共31例阳性,并在脊柱发现病灶131个.经统计学处理结果:转移瘤的阳性检出率磁共振DWI(97.5％)高于核素骨显像检查(77.5％)(采用两独立样本t检验,P＜0.05).病灶腰椎体的ADC值[(1.37±0.51)×10-3mm2/s]明显高于邻近正常腰椎体[(0.534±0.23)×10-3mm2/s],DWI病灶与邻近正常腰椎体信号强度的骨髓对比率(1.65±1.38)差异大.椎体转移瘤病灶的高信号(162个)和骨髓对比率变化检出比核素骨显像(131个)阳性率高,两者具有显著性差异(P＜0.05).结论:与核素骨显像比较,DWI的高信号或骨髓对比率在脊柱转移瘤的诊断中有一定的优势.     

胸腰椎转移瘤后路手术中骨水泥的应用

目的:探讨骨水泥在胸腰椎转移瘤后路手术中的应用价值.方法:2004年3月～21208年12月,后方入路手术治疗胸腰椎转移性肿瘤患者26例,原发肿瘤:肺癌9例,乳腺癌7例,肝癌4例,前列腺癌2例,肾癌1例,来源不明3例.病灶累及单节段17例,两节段9例.23例伴不同程度的腰背部疼痛:神经功能按Frankel分级:B级6例,C级7例,D级11例,E级2例.术中采用骨水泥联合椎弓根螺钉重建脊柱稳定性,其中骨水泥填塞15个椎体,骨水泥前方重建9个椎体,骨水泥椎体成形11个椎体,10例合并骨质疏松患者同时采用骨水泥加强椎弓根钉道.结果:术中未发现骨水泥放热效应引起的神经功能受损.24例患者获得完整随访,随访时间3～42个月,平均18.2个月,23例术前有不同程度腰背疼痛者术后疼痛消失6例,缓解14例;术前伴神经功能障碍者17例(77%)获得神经功能改善.随访期间未发现骨水泥下沉、椎节塌陷及向前成角.1例骨水泥填塞术后3个月骨水泥界面出现松动,但未引起神经压迫症状.15例随访期间死亡.结论:在胸腰椎转移性肿瘤后路手术治疗中,根据患者的全身情况、预期寿命、肿瘤类型、转移椎体位置及骨密度,充分利用骨水泥独特的理化特性,进行多种不同方式的应用,可以减小手术创伤,提高生存质量.     

Evaluation of a bipolar-cooled radiofrequency device for ablation of bone metastases: preclinical assessment in porcine vertebrae

Background contextCancer spread to the spine affects bone stability and can lead to pathologic fracture and neurologic impairment. Radiofrequency ablation (RFA) recently has gained popularity in treating skeletal tumors. Conventional RFA devices use a monopolar design, which limits the ability to comprehensively treat large tumors in bony tissues and may pose risks to adjacent critical normal neurologic tissues when applied to vertebrae. New bipolar-cooled radiofrequency (BCRF) may generate larger controlled lesions without the same degree of risk to adjacent structures.PurposeThe purpose of this study was to evaluate the feasibility, efficacy, and safety of RFA with the use of a new bone-specific, BCRF probe in a porcine vertebral model and to evaluate the ability of magnetic resonance (MR) imaging to represent histologic outcomes of RFA treatment.Study designBasic science: preclinical in vivo study.MethodsRFA was evaluated in three noncontiguous lumbar vertebrae in six Yorkshire pigs (25–30 kg). Via a transpedicular approach for probe placement, two vertebrae received BCRF treatment and one vertebrae served as a sham control. MR imaging and neurological assessments were conducted pre- and posttreatment as well as immediately before animal sacrifice (n=3 at day 0, n=3 at day 14). MR ablation zones were compared with hematoxylin and eosin–stained histological sections.ResultsWith BCRF, large reproducible zones of ablation were achieved, confined within the vertebrae, without damage to adjacent tissues or the spinal cord. All animals demonstrated normal consistent neurologic behavior pre- and posttreatment. External tissue temperatures around targeted vertebrae were not increased. MR imaging after 14 days was more effective in demonstrating ablation effects than images on day 0, with radiologic findings most apparent on T2-weighted sequences. Histologic analysis of samples corresponded well to the zones of ablation observed on MR images (R=0.9, p<.01).ConclusionsThe study demonstrated feasibility, safety, and effectiveness of BCRF ablation of vertebral bone. This motivates ongoing preclinical evaluation in diseased models to further explore the potential for its use in clinical treatment of metastatic vertebrae.