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141.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis.  相似文献   
142.
美国北卡罗来纳大学教堂丘分校的科学家们使用碳纳米管X线发展出了一种新的计算机断层成像(CT)技术。这种技术与以往的CT相比,扫描速度快很多,并且使用更低的峰值功率。他们的工作发表在最新一期的《Applied Physics Letters》上。  相似文献   
143.
陈唯唯 《放射学实践》2006,21(2):216-216
目的:评价ADC图和动态增强平面回波MR序列对诊断头颈部癌颈部淋巴结转移的临床应用价值。方法:对51名头颈部癌伴颈部淋巴结病变的患行扩散加权(DWI)和动态增强T2。灌注加权。DWI采用单次激发EPI序列,b值为500和1000s/mm^2,并重建出ADC图。多层面MR灌注成像采用单次激发平面回波T2WI,在首过团注Gadolinium-DTPA(0.2ml mol/kgBW)后每两秒采集一次,共采集2min以获得信号强度时间曲线。计算出淋巴结的ADC值和最大信号强度下降的百分比,并与组织病理学进行对照。  相似文献   
144.
目的:探讨X线、CT、MRI等检查手段在外伤性高位截瘫诊断中的价值。方法:4l例外伤性高位截瘫的临床及影像资料作回顾性分析,脊椎损伤采用Denis系统分型;脊髓损伤采用ASIA损伤分级评价其神经功能;以MRI颈髓损伤及临床表现为参照探讨影像检查方法间的相互关系。结果:颈椎损伤:过屈型7列、过伸型12例、轴向负荷型22例;脊髓的压迫程度:Ⅰ型5例、Ⅱ型27例、Ⅲ型9例;椎体骨折34处,附件骨折23处,脱位11处。结论:X线、CT、MRI等检查手段在高位截瘫诊断中相互补充,是颈部分外伤患者不可缺少的检查手段,应当作为常规检查。  相似文献   
145.
子宫腺肌症(adenomyosis)是异位的子宫内膜侵入肌层而产生的,发病率为25%~40%,近年来有明显上升趋势[1],是妇科的常见病之一。由于子宫腺肌症的临床症状、体征、实验室理化指标均没有特异性,临床上与子宫肌瘤很难鉴别,且有21%~40%的病例与子宫肌瘤并发,给临床诊断带来一定困难[  相似文献   
146.
目的评价屈颈MRI对青年性上肢远端肌萎缩症的诊断价值。方法男性患者5例,平均年龄21岁,临床表现为一侧或两侧上肢远端肌萎缩。对照组为健康志愿者,21岁男性8例。2组均行常规及屈颈颈椎MR平扫,矢状、轴面SET1WI、T2WI、液体衰减反转恢复(FLAIR)序列扫描。结果常规颈椎扫描:5例患者下段颈髓变细;屈颈位MR扫描:下颈段颈6以下脊髓前屈、变扁平,矢状径4~6mm,硬膜囊后壁前移,硬膜后间隙明显增宽,可见多发条状、迂曲流空信号影及软组织信号。对照组:常规扫描,下颈段脊髓(颈6~胸2)可见颈膨大,屈颈位脊髓略变细(6~7mm),硬膜囊后壁无前移,硬膜后间隙未见扩张血管影。结论屈颈MRI有助于显示下颈段脊髓及硬膜囊改变,结合临床资料可准确诊断青年性上肢远端肌萎缩症。  相似文献   
147.
疑似肺动脉栓塞患者联合下肢深静脉多层螺旋CT成像研究   总被引:2,自引:0,他引:2  
《中华现代中西医杂志》2005,3(6):508-510,F003
  相似文献   
148.
BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke. OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability. DESIGN: Randomly controlled animal study. SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science. MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope. MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue. RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum. CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy.  相似文献   
149.
目的 探讨磁共振脑表面成像技术在矢状窦旁腩膜瘤手术中的应用价值.方法 分析本院经头颅CT及MRI诊断为矢状窦旁脑膜瘤,利用显微手术技术切除并经病理证实的的22例患者;术前均运用磁共振脑表面成像技术评估与肿瘤关系密切的脑表面回流静脉情况.术中根据成像结果有目的 地保护重要的回流静脉,对比患者手术前后神经功能恢复状况,并进行随访来评价手术效果.结果 22例患者的术前磁共振脑表面成像中脑表面回流静脉与术中所见高度一致.术后患者恢复良好,未出现与静脉损伤相关的并发症.结论 磁共振脑表面成像技术能在术前明确矢状窦旁脑膜瘤与脑表面回流静脉之间关系,可在术前对患者肿瘤表面脑回流静脉做出正确的评估,对脑表面重要回流静脉的保护提供了准确的影像学依据,对患者神经功能的保护及术后恢复起到重要作用.  相似文献   
150.
目的:探讨眼眶病变的MRI诊断与鉴别诊断价值。方法:对29例经临床病理确诊的眼眶病变的病例进行回顾性分析,重点观察该类疾病的MRI表现。结果:眼眶病变29例,包括肿瘤10例。炎症10例,血管性病变3例,眼肌病变6例。其在MRI表现各具有影像学特征,眼眶肿瘤多表现为位于眼眶内、外的局限性软组织肿块,MR T1WI呈等或稍低信号,T2WI呈高或等信号多见;炎性假瘤则表现为眶内局限性软组织肿块或弥漫性异常信号.MR T1WI呈低信号,T2WI呈高信号,常伴有眼肌肥大或眼环增厚,泪腺肿大等。结论:MRI检查能显示眼眶病变的影像学特征,对其诊断及鉴别诊断具有重要价值。  相似文献   
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