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121.
122.
Guo-Wei Ma Martin Pytel Ana Luisa Trejos Victoria Hornblower Jennifer Smallwood Rajni Patel Aaron Fenster Richard A Malthaner 《Computer aided surgery》2007,12(5):270-277
OBJECTIVE: Interstitial brachytherapy is becoming an accepted treatment option for lung cancer patients for whom surgery poses a high risk. Robotic surgery has the potential to deliver brachytherapy seeds into tumors while keeping surgeons at a safe distance from the radioactive source. Our aim was to compare the accuracy, number of attempts, and time needed to place seeds next to a target when using a manual technique, video-assisted thoracoscopic surgery (VATS), and the ZEUS robot for minimally invasive surgery (MIS). METHODS: A brachytherapy seed injector was developed and attached to one of the ZEUS robotic arms. Four subjects each inserted inactive dummy brachytherapy seeds into clear agar-gelatin cubes containing a 1.6-mm stainless steel ball target. Two orthogonal radiographs were taken of each agar cube, and the corresponding distances were measured in triplicate using ImageJ processing software. The mean distance between the center of each seed and the corresponding target was calculated using the Pythagorean theorem. Comparisons were made using analysis of variance, t-tests, and Kruskal-Wallis tests, as appropriate. RESULTS: A total of 384 tests (128 for each technique) were performed. The median accuracies for the manual technique, VATS, and ZEUS were 1.8 mm (range: 0.9-6.7 mm), 2.4 mm (range: 1.0-11.3 mm), and 3.6 mm (range: 1.3-16.7 mm), respectively (p < 0.01). The median numbers of attempts for the manual technique, VATS, and ZEUS were 1 (range: 1-5), 4 (range: 1-14), and 3 (range: 1-20), respectively (p < 0.01). The median times for the manual technique, VATS, and ZEUS were 3.0 s (range: 1-43 s), 86.5 s (range: 6-372 s), and 64.5 s (range: 5-356 s), respectively (p < 0.01). CONCLUSIONS: The manual technique is the most accurate, least traumatic, and fastest method of inserting seeds into tumors. The ZEUS robotic platform was able to place seeds beside a target within a clinically acceptable distance, with an acceptable amount of trauma and time required. It achieved results equal to or better than those obtained with VATS. 相似文献
123.
Homid Fahandezh-Saddi Díaz Antonio Ríos-Luna Eduardo García-Rey Ma Jesus Rodea Butragueño Manuel Villanueva-Martinez Ma Elena Cantero-Yubero Miguel del Cerro-Gutiérrez 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(1):105-109
Treatment of chronic osteomyelitis of distal tibia is complex. It often requires the association of antibiotic therapy and a surgical procedure. This consists of exhaustive debridement of infected bone and soft tissue which must have adequate cutaneous coverage and vascular supply which enables creating a barrier to microorganisms and greater resistance to infection. Free or pedicled muscular flaps have been the techniques most often used for this type of lesions. Free flaps require a precise microsurgical technique and prolonged surgery. Pedicled muscular flaps do not provide sufficient coverage and vascularisation of the distal tibia for large size defects. The fasciocutaneous flap has been used for the treatment of coverage defects in the perimalleolar area and the heel. We report the utility of this flap as management of chronic osteomyelitis of the distal third of the tibia with complete healing of the infection and correct cutaneous coverage without complications. 相似文献
124.
拉萨地区高原肺水肿经颅多普勒21例分析 总被引:1,自引:0,他引:1
目的:通过经颅多普勒(TCD)检测,了解高原肺水肿(HAPE)患者颅内脑底动脉环上的主要动脉血流动力学及各血流的生理参数,为高原肺水肿的诊断及治疗提供一些参考.方法:将已确诊的HAPE患者,与颞窗通过低频脉冲多普勒(2MHZ),获得颅内脑底动脉环上的主要动脉的多普勒超声频移信号,进行TCD检测.结果:TCD检测后了解到颅内脑底动脉环上的主要动脉:颈内动脉末梢、大脑中动脉、大脑前动脉血流速度(收缩期血流速度,平均血流速度,舒张末期血流速度)与正常人的TCD测值相比明显增快,但舒张末期血流速度(VE )增快较收缩期血流速度(VP )不明显,故频谱仍为低阻波形,搏动指数(PI)、收缩期血流速度与舒张末期血流速度的比值(S/D)正常,阻力指数有所降低.结论:经TCD检测可知高原肺水肿患者在高原(在低氧环境下),颅内主要脑血管扩张,脑血流量增加即颈内动脉系统的MCA,ACA,PICA血流速度(Vs,Vm,Vd)增快,通过TCD检查可为高原医生早期诊断及治疗提供参考. 相似文献
125.
Ramirez Claudia C. MD Ma Fangchao MD PhD Federman Daniel G. MD † Kirsner Robert S. MD PhD ‡§ 《Dermatologic surgery》2005,31(7):748-753
Background Results from in vitro and animal studies suggest that cyclooxygenase (COX) inhibitors may reduce the risk of melanoma, but among humans, the evidence remains limited.
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
126.
保留脊柱后方韧带复合体腰椎管扩大术的基础研究与临床应用 总被引:1,自引:0,他引:1
目的评价保留脊柱后方韧带复合体腰椎管扩大术临床疗效及生物力学特征。方法取8个新鲜腰骶椎标本,根据处理方法,分为3组。A组:8个完整腰骶椎标本进行生物力学测定;B组:A组测试后,切除L3-5 3个全椎板,保留后方韧带复合体,即为保留脊柱后方韧带复合体的腰椎管扩大术(改良术式);C组:B组测试后,将保留的韧带复合体切除,即为传统术式。3组均行轴向压缩实验、三点弯曲实验及扭转实验。2000年6月-2006年6月,收治309例腰椎管狭窄症患者,行保留脊柱后方韧带复合体腰椎管扩大术。其中男152例,女157例;年龄20~80岁,平均57.2岁。病程3个月~41年。单纯腰椎管狭窄症55例;腰椎管狭窄合并腰椎间盘突出症254例,其中合并L4、5椎间盘突出105例,L4~S1椎间盘突出56例,L5、S1椎间盘突出86例,L2、3高位腰椎间盘突出7例。术后采用JOA下腰痛手术疗效评分标准、患者手术满意度及影像学观察进行疗效评定。结果轴向压缩实验:前屈时,A、B组应变、应力、轴向位移均小于C组(P〈0.01);轴向刚度大于C组(P〈0.01)。后伸时,A、B、C3组间上述指标差异无统计学意义(P〉0.05)。三点弯曲实验:在相同弯矩下,挠度、倾角、弯曲刚度A、C组及B、C组比较,差异均有统计学意义(P〈0.01),A、B组间差异无统计学意义(P〉0.05)。扭转实验:相同扭角条件,B组承载的扭矩大于C组(P〈0.01);相同扭矩条件,B组扭角小于c组(P〈0.01),B组扭转刚度大于C组(P〈0.01)。临床应用结果:术中神经根牵拉伤7例;术后脑脊液漏5例,伤口感染4例,经处理后痊愈。309例均获随访,随访时间1~7年。根据JOA下腰痛评分标准,JOA评分平均改善率为86.0%;其中优163例,良112例,可34例,优良率89%。X线片未见椎体不稳。患者手术满意度为87%。结论保留脊柱后方韧带复合体腰椎管扩大术有利于保持脊柱的力学稳定性,疗效佳。 相似文献
127.
128.
Li-xin Yu Jun-sheng Ye Jian Xu Wen-feng Deng Cong-xiang Han Gui-rong Ye Shao-jie Fu Chuan-fu Du Jun-jie Ma Yi-bin Wang Xiao-you Liu Chuan-jiang Li 《第一军医大学学报》2003,23(12):1332-3, 1337
OBJECTIVE: To study the effect of combined transplantation of the liver and the pancreas in diabetic patients with end-stage liver disease, and explore the optimal surgical procedure. METHODS: Simultaneous orthotopic liver and heterotopic pancreas-duodenum transplantations were performed in a patient diagnosed as having chronic hepatitis B, hepatocirrhosis, hepatic cellular cancer, and insulin-dependent diabetes. Immunosuppression therapy utilized prednisone, tacrolimus (FK506), mycophenolate mofetil (MMF), and simulect. The function of the liver graft, serum amylase and lipase, blood glucose, and C-peptide were monitored after transplantation. RESULTS: Insulin was withdrawn at the 6th day after operation, good liver allograft functional recovery was achieved, without such complications as pancreatitis, thrombosis, and localized infections. CONCLUSION: End-stage liver disease with concomitant insulin-dependent diabetes is the indication for combined liver-pancreas transplantations, for which simultaneous orthotopic liver and heterotopic pancreas-duodenum transplantations may constitute the optimal surgical approaches as the primary choice. 相似文献
129.
Hailong Tao Jianzeng Dong Ronghui Yu Changsheng Ma 《Journal of interventional cardiac electrophysiology》2007,19(1):41-43
Straight back syndrome (SBS) is a thoracic deformity with absence of upper thoracic spine kyphosis and heart compression.
The anatomic abnormity of SBS may raise the difficulty of introcardial operation and increase the complicated risk of intervention
performance. Here we report a case of SBS with complicated transseptal puncture during intervention catheter ablation of atrial
fibrillation. 相似文献
130.
目的:研究外伤性脾切除术后中医辨证与免疫功能变化的关系.方法:选择15例脾切除和15例非脾切除患者作为观察对象,以其症状、舌苔、脉象及免疫功能的测定作为观察指标,观察其中医辨证与免疫功能变化.结果:脾切除组在术后早期可出现脾胃虚弱的证候群,同时免疫功能测定补体C3、免疫球蛋白IgG、免疫球蛋白IgM的水平明显降低,与非脾切除组有显著性差异.结论:脾切除容易造成患者术后出现的脾胃虚弱症候群,并降低患者的免疫功能. 相似文献