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991.
小肠磁共振水成像检查方法及其诊断价值 总被引:2,自引:0,他引:2
目的探讨小肠磁共振水成像检查方法及其对小肠疾病的诊断价值。方法本组28例小肠磁共振水成像。25例检查前30min口服0.9%氯化钠注射液或5%葡萄糖氯化钠注射液1500ml,检查前10min静脉注射山莨菪碱20mg;3例小肠梗阻直接进行小肠磁共振水成像,6例增强扫描。诊断结果与插管法小肠气钡造影结果对照。部分病例经手术、病理证实。结果28例小肠磁共振水成像检查均获得成功,图像质量满足诊断要求。正常小肠10例,Crohn’s病2例,十二指肠乳头癌3例,十二指肠腺瘤样增生1例,十二指肠憩室2例,小肠腺癌3例,回肠息肉1例,空肠间质瘤2例,回肠梗阻3例,小肠系膜扭转1例。18例小肠器质性病变诊断敏感性100%(18/18),特异性77.8%(14/18)。结论磁共振水成像对小肠病变的诊断是一种有效的检查方法。 相似文献
992.
目的探讨多层CT冠状动脉血管成像检查患者中心肌桥的特征及临床意义。方法临床确诊冠心病或疑似冠心病而行多层螺旋CT冠状动脉血管成像检查的病例875例,男579例,女296例,年龄30~87岁,平均60岁。采用回顾性心电门控扫描,心率>75次/min,重建相位区间为30%~40%,心率<75次/min,重建相位区间为40%~50%,获得最大密度投影、曲面重组、容积重组图像,从多角度显示左、右冠状动脉主干及其各主要分支。结果检出89例心肌桥患者,检出率10.2%。其中36例(40.5%)管腔呈不同程度的狭窄(<50%)。发生于前降支中段者71例(79.8%),肌桥厚度0.06~0.55cm,其中20例近段伴有不同程度的粥样硬化斑块,管腔狭窄均接近50%。单纯心肌桥患者有心绞痛症状者39例,心肌桥伴有冠状动脉粥样硬化者有心绞痛症状23例。结论MSCT冠状动脉血管成像可以明确检出心肌桥,为临床的诊断和治疗提供了更具价值的信息。 相似文献
993.
Accelerating cardiac cine 3D imaging using k-t BLAST. 总被引:1,自引:0,他引:1
Sebastian Kozerke Jeffrey Tsao Reza Razavi Peter Boesiger 《Magnetic resonance in medicine》2004,52(1):19-26
By exploiting spatiotemporal correlations in cardiac acquisitions using k-t BLAST, gated cine 3D acquisitions of the heart were accelerated by a net factor of 4.3, making single breathhold acquisitions possible. Sparse sampling of k-t space along a sheared grid pattern was implemented into a cine 3D SSFP sequence. The acquisition of low-resolution training data, which was required to resolve aliasing in the k-t BLAST method, was either interleaved into the sampling process or obtained in a separate prescan to allow for shorter breathhold durations in patients with heart disease. Volumetric datasets covering the heart with 20 slices at a spatial resolution of 2 x 2 x 5 mm3 were recorded with 20 cardiac phases in a total breathhold duration of 25-27 sec, or 18 sec if partial Fourier sampling was additionally employed. The feasibility of the method was demonstrated on healthy volunteers and on patients. The comparison of endocardial area derived from single slices of the 3D dataset with values extracted from separate single-slice acquisitions showed no significant differences. By shortening the acquisition substantially, k-t BLAST may greatly facilitate volumetric imaging of the heart for evaluation of regional wall motion and the assessment of ventricular volume and ejection fraction. 相似文献
994.
椎管内占位病变的CT评价 总被引:4,自引:0,他引:4
本文回顾性分析了28例椎管内占位病变(包括椎管内肿瘤24例、蛛网膜囊肿2例、硬膜外脓肿和椎同盘突出各1例)的CT表现。着重讨论了造影剂增强CT的特征。大多数增强CT可显示肿块的轮廓,有助于肿块定位。室管膜瘤和星形细胞瘤的增强CT表现类似,但雪旺氏瘤、海绵状血管瘤和脓肿具有增强CT特征;同时还对脂肪瘤、脊膜瘤和蛛网膜囊肿的增强CT特征进行了探讨。增强CT定位困难时,CTM可有很大的帮助。 相似文献
995.
Adult medulloblastoma: review of 13 cases with emphasis on MRI 总被引:8,自引:1,他引:7
Medulloblastomas are generally associated with childhood, but 14–30% occur in adults, accounting for 1% of adult central nervous system tumors. While approximately one third of adult medulloblastomas present as vermian tumors similar to those seen in childhood, the majority differ substantially from the childhood variety. In this series of 13 patients, 5 had lateral, seemingly extra-axial masses in the cerebellopontine angle or at the tentorium, simulating meningiomas or acoustic neuromas, but angiographic hypovascularity in 2 of the latter suggested a diagnosis other than meningioma. Of 4 paramedian tumors, 3 diffusely infiltrated the cerebellar white matter, showed little or no gadolinium enhancement and were not associated with hydrocephalus. Hydrocephalus was present in less than half of our patients; in childhood the reported incidence is 85–100%. A possible association with pregancy was noted. 相似文献
996.
为了提高对胃平滑肌肿瘤的认识,作者回顾性分析了20例经手术、病理证实的胃平滑肌肿瘤的钡餐造影所见。结果表明,胃底与胃体上部是胃平滑肌肿瘤的病变高发区。本病具有典型胃粘膜下肿瘤的X线特征,腔内型者可见胃内边缘光滑的充盈缺损或软组织肿块,粘膜展平或推移;腔外型者可见突出胃外肿块或/和胃与邻近脏器受压;腔内外型者具有上述双重特征,肿瘤较大者多有溃疡形成,甚至囊变,根据肿瘤的大小、形态、生长类型及溃疡表现可作良恶性鉴别。本病的术前诊断主要依靠X线钡餐检查,但无胃肠压迫的腔外型肿瘤,钡餐则难以发现,CT或选择性血管造影可助诊断。 相似文献
997.
M. Uhl K. H. Allmann C. Ihling M. P. Hauer W. Conca M. Langer 《Skeletal radiology》1998,27(12):677-682
Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis.
Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint
surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS
spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge
staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically
tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions
in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of
cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions
in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions
in rheumatoid arthritis. 相似文献
998.
Sybille Spicker Jörg B. Schulz Dirk Petersen Michael Fetter Thomas Klockgether Johannes Dichgans 《Journal of neurology》1995,242(8):517-521
Eye movements were studied in 13 patients with Friedreich's ataxia and correlated with MRI findings to investigate whether oculomotor abnormalities can be traced to cerebellar disturbances in this disease. One of the most prominent eye signs was fixation instability (square-wave jerks, SWJ.). Besides SWJ the patients showed various combinations of cerebellar, vestibular and brain-stem oculomotor signs. Our patients did not comprise a homogeneous group with regard to their oculomotor findings. There was no correlation between the severity of any of the so-called cerebellar oculomotor disturbances and the number of SWJ. We tried to correlate the extent of oculomotor disturbances with floccular atrophy and atrophy of the dorsal vermis on MRI in seven of the patients. None of the oculomotor features (including SWJ) correlated with flocculus or dorsal vermis size. Furthermore, floccular and vermal measurements on MRI were normal. Accordingly, we think it unlikely that the oculomotor disturbances, including SWJ, are attributable to cerebellar pathology per se. 相似文献
999.
医疗照射剂量水平及其防护 总被引:1,自引:0,他引:1
本文讨论了医疗照射的频度、剂量水平和防护问题。诊断X线检查频度在发达国家为每年每千人300—900人次,在发展中国家为100—200人次/千人·年,我国为124.5人次/千人·年;平均有效剂量当量在发达国家为1mSv/年·人,全世界平均值为0.4mSv/年·人,我国为 0.5mSv/年·人;医疗照射所致超额死亡率在发达国家估计为10—15/百万人,我国为4.27/百万人。 我国的诊断X线检查频度和剂量水平将进一步增长,为减少医疗照射,我们必须采取预防措施。 相似文献
1000.
①目的进一步了解动物心肌细胞的种属特性。②方法应用电子显微镜对鲤、蟾蜍、鳖和家鸽等几种脊椎动物心肌细胞进行了观察。③结果这几种动物心肌细胞的侧面连接较多见。除家鸽外,心肌细胞的肌原纤维的排列比较松散。所观察各种属动物的心肌细胞均含有单位膜包绕的特殊颗粒,以心房肌细胞为多,但这几种动物心肌细胞的特殊颗粒在大小、形态、分布等方面均有明显差异。家鸽心肌细胞的特殊颗粒小,常成群分布于肌膜下方,并可见颗粒外排迹象。其它种属的特殊颗粒大小不等,多位于核周区。横小管系统以家鸽心室肌最易辨认,其它均少见。家鸽心肌细胞中的肌原纤维较其它动物密集,且排列整齐。④结论脊椎动物心肌细胞的超微结构有种属特性。 相似文献