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991.
Feng Yuan Hui-Lin Yang Kai-Jin Guo Jiang-Shan Li Kai Xu Zhi-Ming Zhang Tian-Si Tang 《European spine journal》2013,22(1):39-45
Purpose
This anatomic, radiographic study investigated locational differences in the C2 pedicle and isthmus [pediculoisthmic component (PIC)] and characterized its narrowest section for clinical application in posterior C2 screw fixation.Methods
Structures surrounding the transverse foramina of 30 dry C2s and 10 C3s were compared morphologically. Spinal CT scans of 32 Chinese adults were subjected to volume rendering and multiplanar reconstruction to identify the narrowest C2 PIC, and correlative parameters were measured and analyzed.Results
Inferior C2 and C3 structures were morphologically similar. In superior view, the C2 superior facets lay on the transverse foramen and the upper portion between superior and inferior facets was flat (average mediolateral angle, 11.1° ± 2.4°). In inferior view, the posteroinferomedial portion of the C2 transverse foramen displayed a partially tubular structure (average mediolateral angle of projection, 42.6° ± 4.9°). Average height and width were 11.6 and 6.9 mm. The inner medullary cavity was elliptical and the middle site of endosteal diameter was 3.3 ± 1.9 mm. Medial internal cortical bone was significantly thicker than lateral bone (P < 0.01).Conclusions
The PIC is located between superior and inferior C2 facets. The superior flat area is the isthmus and the inferomedial area connecting the inferior facet and vertebral body is the pedicle. The pedicle is partially tubular and projects posteromedially to the transverse foramen. The narrowest PIC section is the narrowest point of the C2 pedicle. Considering its thin lateral cortical bone, medial and superior pedicle screw placement and preoperative CT reconstruction are recommended. 相似文献992.
Purpose
To identify anterior spinal artery (ASA) infarct or occlusion by CT angiography (CTA) in patients with cervical spondylotic myelopathy (CSM).Methods
Fourteen patients with CSM were performed CTA of ASA after admission. T2-weighted hyperintensity of MR image was compared with image of CTA of ASA.Results
All patients presented spinal canal sagittal diameter compression from 10 to 80 % and different T2-weighted hyperintensity of MR images. No ASA infarct or occlusion was found in CSM patients.Conclusion
ASA infarct or occlusion is not commonly seen in CSM patients with spinal canal sagittal diameter compression less than 80 %. Pathological changes about T2-weighted hyperintensity of MR image in CSM have no close correlation with ASA infarct. 相似文献993.
Tomohiro Izumi Toru Hirano Kei Watanabe Atsuki Sano Takui Ito Naoto Endo 《European spine journal》2013,22(11):2569-2574
Background
Two-dimensional imaging is not adequate for evaluating ossification of the posterior longitudinal ligament (OPLL). This study was designed to evaluate the accuracy of a novel computed tomography (CT)-based three-dimensional (3D) analysis method that we had devised to measure volume changes in OPLL.Subjects and methods
Twenty OPLL patients (12 male and 8 female; mean age 63.6 years) who were being followed conservatively were examined twice with an interval of at least 1 year between the two scans. The mean interval was 22 (range 12–45) months. A 3D model was created with DICOM data from CT images, using the MIMICS® software to calculate the volume. The mean ossification volume was determined from two measurements. Since ossification size varies widely, evaluation of change in volume is generally affected by the original size. Therefore, the change in ossification volume between the first and second CT examinations was calculated as the annual rate of progression.Results
The type of OPLL was classified as continuous in 3 patients, segmented in 3, and mixed in 14. The mean ossification volume was 1,831.68 mm3 at the first examination and 1,928.31 mm3 at the second, showing a significant mean increase in ossification volume. The mean annual rate of lesion increase was 3.33 % (range 0.08–7.79 %).Conclusion
The 3D method used allowed detailed OPLL classification and quantification of change in the ossified volume. Thus, this method appears to be very useful for quantitative evaluation of OPLL with only minimal measurement error. 相似文献994.
Giuseppe Curigliano Xavier Pivot Javer Cortés Anthony Elias Rossano Cesari Reza Khosravan Mary Collier Xin Huang Patricia E. Cataruozolo Kenneth A. Kern Aron Goldhirsch 《Breast (Edinburgh, Scotland)》2013,22(5):650-656
PurposeThis randomized, open-label phase II study compared the efficacy of sunitinib monotherapy with that of single-agent standard-of-care (SOC) chemotherapy in patients with previously treated advanced triple-negative breast cancer (TNBC).MethodsPatients with advanced TNBC, relapsed after anthracycline- and taxane-based chemotherapy, were randomized to receive either sunitinib (37.5 mg/day) or the investigator's choice of SOC therapy. Progression-free survival was the primary endpoint.ResultsMedian progression-free survival was 2.0 months with sunitinib and 2.7 months with SOC chemotherapy (one-sided P = 0.888). Median overall survival was not prolonged with sunitinib (9.4 months) compared with SOC chemotherapy (10.5 months; one-sided P = 0.839). The objective response rate was 3% with sunitinib and 7% with SOC chemotherapy (one-sided P = 0.962).ConclusionsSunitinib monotherapy did not improve efficacy compared with SOC chemotherapy in patients with previously treated advanced TNBC, for which identification of effective treatments and therapeutic targets remains an urgent need.Trial registrationNCT00246571. 相似文献
995.
目的:比较数字化摄影(DR)与多层螺旋CT(MSCT)在诊断足踝部骨折及关节脱位的应用价值。方法:分析2010年8月至2012年8月收治的52例足踝部骨折及脱位患者(男37例,女15例,年龄15~49岁)的DR及MSCT资料,并与手术或出院诊断对比,比较两者诊断骨折数量、关节脱位的区别,采用R统计软件Wilcoxon符号秩检验(Wilcoxon signed rank test)进行统计学分析。结果:52例MSCT结果与术后或出院诊断结果完全相符。MSCT诊断骨折172处,DR诊断骨折98处,两者在骨折诊断中差异有统计学意义(V=1081,P<0.05);MSCT诊断关节脱位24例,DR诊断关节脱位16例,两者在关节脱位诊断中差异有统计学意义(V=21,P<0.05)。MSCT纠正DR骨折诊断定位6例。结论:MSCT对足踝部骨折及关节脱位的诊断优于DR。DR应首选2个部位的检查。当DR诊断结果不明确或与临床症状不相符时应选择MSCT及多平面重建(MPR)检查,可避免漏诊及误诊。 相似文献
996.
目的:观察腰椎周围肌间隙的解剖学与影像学特点,为腰椎后路椎旁肌间隙入路的选择和操作提供形态学依据.方法:选取18具成人尸体湿性躯干标本,一侧行局部解剖观察腰椎周围肌肉及其毗邻结构,另一侧行模拟肌间隙手术入路,观察不同肌间隙的解剖构成及其显露腰椎相关结构的特点;同时选取30例健康志愿者的腰部MRI与CT图像,观察肌间隙的影像学显示特点.结果:Wiltse间隙位于多裂肌与最长肌之间,由脂肪及疏松结缔组织填充,无血管、神经穿行;通过该间隙可清晰显露腰椎关节突关节、椎间孔及横突;75.0%的CT片和93.3%的MRI片可显示Wiltse间隙.LIMP间隙位于最长肌与髂肋肌之间,由一层薄而透明的筋膜分隔两肌,69.4%标本可见脊神经后支的肌支穿行间隙内;该间隙可满意显露椎间孔区及椎弓根;41.6%的CT片和56.6%的MRI片可显示LIMP间隙.Watkins间隙位于髂肋肌与腰方肌之间,由腰背筋膜中层及少量脂肪分隔肌肉形成,75.0%标本可见脊神经后支的皮支及伴行血管走行;该间隙可满意显露椎间孔及椎体两侧;63.3%的CT片和86.6%的MRI片可显示Watkins间隙.结论:熟悉腰椎不同肌间隙的形态特点及穿行结构,术前影像学准确观测有助于椎旁肌间隙入路的选择与操作. 相似文献
997.
Robert DOrtenzio Stefano Tolhurst Melissa Harvey Ravi Ghag Manraj KS Heran 《Journal of Radiology Case Reports》2021,15(3):1
Mass lesions presenting at the craniocervical junction often present a unique challenge due to the complex anatomic arrangement limiting access for tissue diagnosis. The transoral approach has predominantly been used for percutaneous vertebroplasty of high cervical vertebrae with limited literature describing image guided biopsy for bony lesions in this region in the pediatric patient. We describe a technique of computed tomography guided transoral biopsy of a poorly differentiated chordoma located at the C1–C2 level in a 5-year-old child, and review this diagnosis. 相似文献
998.
目的:探讨颧骨颧弓缩小联合下颌角截骨术前、术后颞颌关节和咬肌的变化。方法:随机选取颧骨颧弓及下颌角肥大者80例,于术前、术后10天分别做三维CT检查,并对颜面部进行三维测量,采用自身对照进行配对资料t检验。结果:颧骨颧弓及下颌角截骨整形术后0°指标及60°指标术前术后差异无统计学意义(P>0.05),120°指标及180°指标术前术后差异有统计学意义(P<0.05);咬肌宽度及厚度术前术后差异有统计学意义(P<0.05)。结论:颧骨颧弓及下颌角截骨整形术后短期内颞颌关节上间隙及关节后间隙发生了改变,差异有统计学意义但差值较小,颞颌关节的改变仍在其代偿范围内;由于术中部分骨质的去除及咬肌被剥离附着位置发生改变再加上手术操作对咬肌的损伤,咬肌的形态随之改变,短期内咬肌宽厚度较术前增大。 相似文献
999.
1000.
目的 探讨结肠气钡双重造影和结肠CT在结直肠疾病诊断中的应用价值,并对比分析两种检查方法的优缺点.方法 回顾性分析2005年6月至2013年8月我院213例结肠气钡双重造影和结肠CT检查结果,对比观察两种检查方法所检出的病种、结直肠肿瘤和息肉的大小、部位及并发症发生情况.结果 结肠气钡双重造影对溃疡性结肠炎、慢性阑尾炎、憩室等疾病和近端结肠及小病灶的诊断能力优于结肠CT;结肠CT对结直肠肿瘤及远端结肠的诊断能力则优于结肠气钡双重造影.结论 结肠气钡双重造影和结肠CT各具优势,在临床工作中应视具体情况加以选择或联合应用. 相似文献