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61.
目的 探讨螺旋CT多期增强扫描对小肝癌诊断的临床价值.方法 回顾性分析75例确诊为小肝癌患者的临床资料,所有的病例行螺旋CT多期增强扫描,时间分别为动脉期25~35 s,门脉期60~80 s,延迟期4~6 min,经静脉以2.5~3 ml/s的速率高压注射造影剂80~95 ml,观察小肝癌在不同时期的强化情况.结果 共检出84个病灶,动脉期、门脉期以及延迟期的检出率分别是90.48%、71.43%和69.05%,而且动脉期检出的病灶数明显多于门脉期和延迟期(P<0.01).结论 螺旋CT多期增强扫描使小肝癌呈现典型的表现,提高了诊断与鉴别诊断能力及小肝癌的检出准确性.  相似文献   
62.
PURPOSE: Intracranial arterial wall calcifications are frequently observed on routine head computed tomography (CT) images. The purpose of this study was to evaluate whether calcification of the intracranial carotid artery on CT images could predict atheromatous plaque and luminal stenosis. MATERIALS AND METHODS: A total of 259 patients were examined using three-dimensional CT angiography using high-resolution 64 detector scanners. We examined patients from the petrous portion to the top of the internal carotid arteries. We evaluated the existence of calcification and atheromatous plaque based on our criteria retrospectively. The thickness of calcification was measured in each vessel, and the shape of calcification was classified into three types. RESULTS: There was low correlation between the thickness of the calcification and luminal stenosis, but the shape of the calcification corresponded well to the stenosis. The population of patients with >50% stenosis of the intracranial carotid artery differed statistically significantly for each calcification shape. There was a high negative predictive value (97.7%) in the correlation between the existence of calcification and atheromatous plaque on the multidetector CT images. CONCLUSION: Calcification of the intracranial carotid artery on CT images shows a high negative predictive value for the existence of atheromatous plaque in the same artery. The thickness of the calcification did not correlate well with luminal stenosis, but its shape seemed to predict luminal stenosis.  相似文献   
63.
Gardner MJ  Briggs SM  Kopjar B  Helfet DL  Lorich DG 《Injury》2007,38(10):1189-1196
BACKGROUND: Intertrochanteric hip fractures have become more common as the elderly population continues to increase, and surgical stabilisation of these fractures remains a persistent challenge. The purpose of this study was to analyse the ability of a new helical blade device to stabilise intertrochanteric hip fractures, and to further determine which factors are important in implant stability. METHODS: Two hundred and fifty-five patients with an intertrochanteric hip fracture were treated with a trochanteric fixation nail (TFN), 97 of whom fit strict radiographic and follow-up criteria and were included in the study group. After adjusting for magnification and rotation, blade migration within the femoral head and telescoping of the blade along its axis were measured using a custom-designed grid system. Multivariate regression analyses were performed to determine which variables predicted blade migration and telescoping. RESULTS: Fifty-nine fractures were classified as stable, and the remaining 38 were unstable. Mean telescoping was 4.3 mm in the unstable group, compared to 2.6 mm in the stable group (p<0.05). Blade migration within the femoral head averaged 2.2 mm overall, with no difference between stable and unstable fractures. For both telescoping and blade migration, no significant change occurred after the 6-week time point in the stable or unstable group. Nail length, age, and gender did not have a significant effect on either blade migration or telescoping implant position change. Of the initial cohort of 255 patients, five cutouts and one nonunion occurred, three of which required subsequent procedures. CONCLUSIONS: Subtle migration ( approximately 2mm) of the tip of the blade within the femoral head occurred in all fractures, but this did not preclude maintenance of reduction and fracture healing, and was not predicted by fracture type, reduction quality, age, or gender. More telescoping occurred in unstable compared to stable fractures, but this averaged 4mm and did not affect stable fixation or fracture healing. All position changes occurred within the first 6 weeks postoperatively, with no subsequent detectable migration or telescoping. Clinical correlations will be needed in the future to determine the significance of small amounts of migration or differences in telescoping, but this device appears to provide effective fixation in both stable and unstable intertrochanteric hip fractures.  相似文献   
64.
AIM: The purpose of this study was to review and evaluate the efficacy of contrast-enhanced helical computed tomographic (CT) scanning in evaluating potential mediastinal injuries in stable patients with transmediastinal gunshot wounds (TMGSWs). METHODS: During the review period, 01 January 2002-31 May 2005, the medical records of all haemodynamically stable patients with TMGSWs were retrieved and reviewed for demographics, diagnostic workup, treatment and complications. Screening CT was considered inconclusive in the presence of a mediastinal haematoma, pneumomediastinum or a missile track in proximity of major mediastinal structures. Inconclusive CT scans were further evaluated with angiography, and/or oesophography, and/or cardiac ultrasound. RESULTS: Fifty consecutive haemodynamically stable patients with TMGSWs were identified. Thirty-five CT scans were performed, of which 29 (82.9%) were conclusive. Further diagnostic evaluation in the remaining six patients showed no injury. All patients were observed in a high-care unit and there were no missed injuries. The hospital charges generated with the CT scan based protocol were significantly less than with standard evaluation. CONCLUSION: Contrast enhanced helical CT scanning is a safe, efficient and cost effective screening tool for evaluating haemodynamically stable patients with TMGSWs.  相似文献   
65.
66.
肾癌常见病理亚型的多层螺旋CT表现及诊断   总被引:4,自引:0,他引:4  
目的:探讨肾细胞癌常见病理亚型多层螺旋CT多期增强扫描表现特征,提高其诊断及鉴别诊断水平。方法:回顾性分析192例经手术和病理证实的肾细胞癌多层螺旋CT平扫及增强检查皮髓质期、实质期和排泄期扫描的影像资料,观察并比较各种亚型CT动态强化方式及表现特征。结果:平扫CT,160例透明细胞癌中密度不均141例,24例乳头状癌中密度不均17例,而8例嫌色细胞癌中6例密度均匀。多期增强检查,透明细胞癌(153/160)增强皮髓质期呈明显不均匀强化,实质期强化程度快速下降,排泄期持续下降,表现为"快进快出"型;而乳头状癌(23/24)和嫌色细胞癌(6/8)皮髓质期均呈轻、中度强化,实质期和排泄期呈持续强化,表现为"渐进性强化"型。经统计学分析,三种亚型肾癌间的平扫及排泄期CT值无统计学差异;而皮髓质期及实质期透明细胞癌与乳头状癌和嫌色细胞癌间的CT值有统计学差异,但乳头状癌与嫌色细胞癌间CT值在皮髓质期无统计学差异。结论:多层螺旋CT多期增强扫描对透明细胞癌与其它亚型肾癌的鉴别有一定的价值,但乳头状癌与嫌色细胞癌的鉴别常常较为困难。  相似文献   
67.
The purpose of this study is to examine risk factors for late rectal toxicity for localized prostate cancer patients treated with helical tomotherapy (HT). The patient cohort of this retrospective study was composed of 241 patients treated with HT and followed up regularly. Toxicity levels were scored according to the Radiation Therapy Oncology Group grading scale. The clinical and dosimetric potential factors increasing the risk of late rectal toxicity, such as age, diabetes, anticoagulants, prior abdominal surgery, prescribed dose, maximum dose of the rectum, and the percentage of the rectum covered by 70 Gy (V70), 60 Gy (V60), 40 Gy (V40) and 20 Gy (V20) were compared between ≤ Grade 1 and ≥ Grade 2 toxicity groups using the Student''s t-test. Multivariable logistic regression analysis of the factors that appeared to be associated with the risk of late rectal toxicity (as determined by the Student''s t-test) was performed. The median follow-up time was 35 months. Late Grade 2–3 rectal toxicity was observed in 18 patients (7.4%). Age, the maximum dose of the rectum, V70 and V60 of the ≥ Grade 2 toxicity group were significantly higher than in those of the ≤ Grade 1 toxicity group (P = 0.00093, 0.048, 0.0030 and 0.0021, respectively). No factor was significant in the multivariable analysis. The result of this study indicates that the risk of late rectal toxicity correlates with the rectal volume exposed to high doses of HT for localized prostate cancer. Further follow-up and data accumulation may establish dose–volume modeling to predict rectal complications after HT.  相似文献   
68.
The classical interpretation of myocardial activation assumes that the myocardium is homogeneous and that the electrical propagation is radial. However, anatomical studies have described a layered anatomical structure resulting from a continuous anatomical helical disposition of the myocardial fibers. To further investigate the sequence of electromechanical propagation based on the helical architecture of the heart, a simplified computational model was designed. This model was then used to test four activation patterns, which were generated by propagating the action potential along the myocardial band from different activation sites.  相似文献   
69.
《Cancer radiothérapie》2022,26(5):654-662
PurposeIntensity-modulated radiotherapy with helical Tomotherapy is a novel radiation therapy technique, which may be beneficial in several features compared to traditional methods. Our aim was to evaluate the local control, overall survival, progression free survival and adverse events in breast cancer patients treated with this new technique.Material and methodsThis is retrospective analysis of patients irradiated with intensity-modulated radiotherapy with helical Tomotherapy. Overall survival and progression free survival curves were plotted with Kaplan-Meier method. We also analysed the overall survival and progression-free survival data by molecular subgroups. Long-term toxicity including skin, cardiac and pulmonary complications were also evaluated. Multivariant logistic regression analysis was performed to determine the predictors of the side effects.ResultsBetween 2009–2015, 179 consecutive patients with 194 treated breasts were irradiated with intensity-modulated radiotherapy with helical Tomotherapy. The median follow-up were 65 months. The overall survival rate was 89.2% (95% confidence interval [95CI]: 83.5–95.4%), while disease-free survival rate was 85.4% (95CI: 80.2–91%). The Human epidermal growth factor receptor 2-positive patients had the best 5-year overall survival data of 95% (95CI: 85.9–100%). Long-term skin toxicity was the most common, seen in a total of 20.7% of the patients.ConclusionIntensity-modulated radiotherapy with helical Tomotherapy could be safely used for adjuvant breast cancer irradiation in patients with complex anatomy and provides favourable long-term prognosis with acceptable late toxicity.  相似文献   
70.
外伤性脑梗死的CT诊断(附39例分析)   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:探讨螺旋CT在外伤性脑梗死诊断中的价值及其特征。方法:对39例头颈部外伤后临床主要表现为不同程度的偏瘫患者行横断面螺旋CT扫描,分析外伤性脑梗死的CT表现。结果:根据临床和CT表现分为两型:I型(21例),外伤性腔隙性脑梗死,好发于基底节-内囊区,均位于豆状核、尾状核及内囊区,呈小片状腔隙性低密度区;Ⅱ型(18例),外伤性大面积脑梗死,为脑叶梗死呈扇形低密度区,与大脑前中后供血动脉或颈内动脉分布一致,范围较大。结论:螺旋CT扫描检查对外伤性脑梗死的准确诊断、估计病变程度,分析两型脑梗死的不同发生机制,为临床诊断、治疗及判断预后提供重要信息。  相似文献   
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