风湿性二尖瓣狭窄心肌病理改变与心肌运动的关系

目的 :探讨风湿性二尖瓣狭窄 (Mitralstenosis ,MS)患者心肌病理改变与心肌运动的关系 .方法 :MS患者 2 2例术前行常规心脏超声及组织多普勒成像 (Dopplertissueimag ing,DTI)检查 ,于心尖四腔切面记录室间隔侧二尖瓣环长轴方向射血期频谱S波和舒张期频谱D波峰值及心电图R波至频谱S波起始点的时间T ,选取 3个波幅最大的心动周期 ,算出此 3个心动周期的平均值S3 、D3 和T3 ;二尖瓣置换术中切取左室乳头肌行病理检查 .结果 :微动脉Di/Do与D3 呈正相关 ,(r =0 .5 0 ,P <0 .0 5 ) ;心肌纤维化程度与T3 呈正相关 ,(r=0 .6 8,P <0 .0 5 ) ;而S3 与D3 呈正相关 ,(r =0 .4 3,P <0 .0 5 ) .结论 :术前DTI检查测量D3 及T3 ,可以反映心肌病理变化 ,有助于对MS患者手术适应证的掌握及对预后的判断     

彩色多普勒超声图指导风湿性心脏病二尖瓣狭窄球囊扩张术91例

目的：应用彩色多普勒超声心动图指导经皮二尖瓣球囊成形术(PBMV)治疗风湿性二尖瓣狭窄的价值、方法：运用彩超对行PBMV的患进行术前术后检查，观察二尖瓣钙化程度及部位、开口形状、瓣口面积、二尖瓣返流(MR)程度、瓣下病变、左房左室大小、左房有无血栓．结果：91例PBMV术后患中，术后MR72例，其中MR新出现19例，MR加重8例、与术前对比，术后二尖瓣开放幅度、二尖瓣口面积、二尖瓣跨瓣压、二尖瓣压差半降时间较术前有明显改善趋势，左房内径、肺动脉内径较术前有缩小趋势．同时，术后左房压、右室压及肺动脉压也有下降趋势。结论：彩超能明确PBMV治疗二尖瓣狭窄的效果。影响：PBMV效果的因素较多，但二尖瓣钙化的程度、部位和瓣膜形态较为重要。     

MMP-9和TIMP-1在实验性肺气肿大鼠肺组织中的表达及其意义

目的研究基质金属蛋白酶(MMP-9)及其组织抑制因子(TIMP-1)在弹性蛋白酶所致肺气肿大鼠肺组织中的表达.方法雄性Wistar大鼠20只,随机分为两组:正常对照组和肺气肿模型组,每组10只.模型组大鼠气管内滴入弹性蛋白酶复制肺气肿模型.25d后,观察各组大鼠肺组织的病理改变,免疫组化方法观察肺组织MMP-9和TIMP-1中的蛋白表达情况.结果肺气肿模型组MMP-9和TIMP-1的表达与正常对照组相比明显增强(P＜0.01),且MMP-9/TIMP-1比值失衡.结论MMP-9/TIMP-1失衡在肺气肿形成中起重要作用.     

Dynamic MRI with projection reconstruction and KWIC processing for simultaneous high spatial and temporal resolution.

A method for dynamic imaging in MRI is presented that enables the acquisition of a series of images with both high temporal and high spatial resolution. The technique, which is based on the projection reconstruction (PR) imaging scheme, utilizes distinct data acquisition and reconstruction strategies to achieve this simultaneous capability. First, during acquisition, data are collected in multiple undersampled passes, with the view angles interleaved in such a way that those of subsequent passes bisect the views of earlier ones. During reconstruction, these views are weighted according to a previously described k-space weighted image contrast (KWIC) technique that enables the manipulation of image contrast by selective filtering. Unlike conventional undersampled PR methods, the proposed dynamic KWIC technique does not suffer from low image SNR or image degradation due to streaking artifacts. The effectiveness of dynamic KWIC is demonstrated in both simulations and in vivo, high-resolution, contrast-enhanced imaging of breast lesions.     

隐性骨折的MRI诊断

目的：探讨骨隐性骨折的MRI诊断价值。方法：对25例外伤患者均行X线平片及MRI检查，10例患者同时行CT检查，受伤部位分别为股骨髁、胫骨近端及MRI检查，10例患者同时行CT检查，受伤部位分别为股骨髁、胫骨近端及胸椎、腰椎。结果：本组25例X线平片均未见骨折征象，CT检查10例亦无明显骨折征象，仅见骨小梁结构较乱，周围软组织肿胀；MRI检查25例显示隐性骨折呈现长T1、短T2或不规则状线形异常信号，其周围可见不规则长T2骨挫伤水肿异常高信号影，均伴有周围软组织水肿的异常信号。结论：MRI能早期诊断骨隐性骨折，若患者局部症状明显，X线检查无阳性征象者行MRI检查应为最佳检查手段。     

Fourier components of inhomogeneously broadened water resonances in breast: a new source of MRI contrast.

High spectral and spatial resolution (HiSS) MR data were acquired at 1.5 T using echo-planar spectroscopic imaging from patients with suspicious breast lesions. The water resonances in small voxels are inhomogenously broadened and often have distinct components. Images were calculated with intensity proportional to the Fourier components of the water resonance in each voxel at different offsets from the peak frequency. The results demonstrate that in breast the off-peak Fourier component images of water are qualitatively different from those derived from the peak height of the water resonance. These differences most likely reflect underlying anatomy or physiology. In conventional images, the superposition of the various Fourier components of the water signal may cause loss of detail. The synthesis of water Fourier component images from high spectral and spatial resolution data may provide a new form of contrast, and increase sensitivity to subvoxel physiology and anatomy.     

k-t2 BLAST: exploiting spatiotemporal structure in simultaneously cardiac and respiratory time-resolved volumetric imaging.

Multidimensional imaging resolving both the cardiac and respiratory cycles simultaneously has the potential to describe important physiological interdependences between the heart and pulmonary processes. A fully five-dimensional acquisition with three spatial and two temporal dimensions is hampered, however, by the long acquisition time and low spatial resolution. A technique is proposed to reduce the scan time substantially by extending the k-t BLAST framework to two temporal dimensions. By sampling the k-t space sparsely in a lattice grid, the signal in the transform domain, x-f space, can be densely packed, exploiting the fact that large regions in the field of view have low temporal bandwidth. A volumetric online prospective triggering approach with full cardiac and respiratory cycle coverage was implemented. Retrospective temporal interpolation was used to refine the timing estimates for the center of k-space, which is sampled for all cardiac and respiratory time frames. This resulted in reduced reconstruction error compared with conventional k-t BLAST reconstruction. The k-t(2) BLAST technique was evaluated by decimating a fully sampled five-dimensional data set, and feasibility was further demonstrated by performing sparsely sampled acquisitions. Compared to the fully sampled data, a fourfold improvement in spatial resolution was accomplished in approximately half the scan time.     

碰撞癌的临床影像学表现及病理分析

目的:探讨碰撞癌的临床影像学表现、发病机制与病理特点。方法:回顾性分析20例碰撞癌的临床影像学资料并结合文献复习,总结其患病率、发病年龄、性别比、好发部位、临床影像学表现、治疗手段、病理特点。结果:碰撞癌罕见,好发年龄大于58岁,男性发病多见,好发部位为食管-贲门,食管-胃底等。临床表现无特殊,术前影像学检查多不能明确诊断,术后病理诊断是唯一的确诊方法。治疗以手术为主,辅以化疗或放疗。病理特点为同一宿主同一部位或器官2个不同类型肿瘤的结合,瘤组织间没有移行和混合,有各自的转移途径,碰撞癌以鳞癌和腺癌的碰撞为主。结论:碰撞癌是一种罕见的恶性肿瘤结合,临床特点有待进一步总结,影像学综合诊断有助于提高其确诊率。     

肝移植术后并发症的影像学评价

目的:采用多种影像学措施评价肝脏移植术后并发症。材料和方法:16例背驮式原位肝移植术患者,术后7天内每日行胸片及胸腹部超声检查。术后2周～12个月,当患者出现发烧、皮肤巩膜黄染及异常B型超声发现时,行上腹部CT检查5例8次、同时行胸部CT检查2例、上腹部MRI及MRCP检查6例、ERCP检查4例、PTC检查2例、“T”管造影2例和下腔静脉造影1例。结果:术后1周内诊断胸腔积液14例(14/16);术后1～2周诊断肺部感染7例(7/16);肺不张4例(4/16)。术后4个月和8个月诊断右肺和移植肝多发转移瘤各1例(2/6);术后3周～10个月诊断胆总管吻合口狭窄、胆管炎、胆泥形成等5例(5/16)。术后2周诊断下腔静脉狭窄1例(2/16)。结论:运用多种影像学检查方法有助于及时诊断肝移植术后并发症。     

彩色多普勒超声对肝癌肝动脉化疗栓塞的疗效评价

目的 :探讨彩色多普勒超声 (CDFI)在评价肝癌肝动脉化疗栓塞 (TAE)疗效中的应用价值。方法 :对 4 8例原发性肝癌TAE术前、后行CDFI检查 ,观察肿瘤大小、血供及肝动脉、门静脉血流动力学改变。结果 :TAE术后大多数肿瘤均有不同程度缩小 ;肿瘤内部及周边血供明显减少 (P <0 0 5 ) ,以肿瘤内血流减少更明显 ,其血供减少程度与肿瘤缩小程度呈正相关 (r =0 75 ,P <0 0 0 1) ,肝动脉峰值流速明显下降 ,门静脉血流速度增快 (P <0 0 0 1)。结论 :CDFI能客观判断肿瘤大小及血流灌注状态 ,是目前检验肝癌TAE效果较理想的影像学检查方法