【作者】 李宁；

【导师】 杨贞振； 毕万利；

【作者基本信息】 山东大学 ， 影像医学与核医学， 2008， 硕士

【摘要】 目的利用3.0T MR低张胰胆管水成像(magnetic resonance cholangiopancreatography,MRCP)和肝脏快速容积采集(liver acquisition with volume acceleration,PropellerLAVA)技术对壶腹周围病变的影像征象进行研究,探讨二者结合在壶腹周围病变诊断及肿瘤术前可切除性评估中的价值及优势,为进一步提高壶腹周围病变的诊断率和治愈率提供可靠的影像学信息。方法对来我院就诊的43例疑为壶腹周围病变的患者行MR检查。所有患者均行常规MRI轴位T1WI、T2WI及T1WI、T2WI脂肪抑制扫描、冠状位FIESTA及2D、3D低张MRCP成像,对其中37例无法明确诊断者进一步行Propeller LAVA多期动态增强扫描,利用工作站中的Reformat、Functool功能对原始图像进行最大强度投影(maximum intensity projection,MIP)及多平面重组(multi-planarreformation,MPR)重建后处理,绘制动态强化曲线。根据病变的间接、直接征象及动态强化特点对其起源、性质、大小及范围做出术前诊断,将所得影像诊断结果与临床随访及病理组织学结果作对照研究,评估该方法诊断的灵敏度、特异度及准确度。将肿瘤病变的Propeller LAVA多期动态增强扫描结果分为3级,并与强化前常规MR平扫结果对比,利用非参数秩和检验法进行统计学处理,P＜0.05时认为差异有统计学意义。结果1.低张MRCP结合Propeller LAVA动态增强诊断结石、炎症、肿瘤的灵敏度及特异度分别为100%及100%、60%及97.4%、96.7%及76.9%,三者诊断准确度分别为100%、93.0%、90.6%。2.30例肿瘤病变中壶腹部癌、胆总管远端癌及胰头癌组织起源诊断准确度分别为93.3%(28/30)、90.0%(27/30)、86.7%(26/30)。3.37例行Propeller LAVA动态增强扫描者中,病变直接征象显示率达89.2%(33/37),肿瘤浸润范围诊断准确度为83.3%(25/30)。其中胰腺癌术前可切除性评估准确度为76.9%(10/13),胆总管远端癌为85.7%(6/7),壶腹部癌为88.9%(8/9)。4.对于临床及病理证实的30例肿瘤性病变,观察直接征象并达到3级以上者,Propeller LAVA动态增强扫描显示25例,MR平扫显示2例,前者明显优于后者,二者比较组间差异有统计学意义(P＜0.05)。5.动态强化曲线显示胆总管癌多于延迟40s—50s达到强化峰值,呈缓进缓出型;壶腹部癌达到强化峰值的时间不均一;胰腺癌强化程度较弱,峰值往往低于壶腹部癌及胆总管癌。结论低张MRCP结合Propeller LAVA动态增强扫描能够全面、直观显示壶腹周围病变的间接及直接征象,在明确肿瘤病变的起源、周围组织血管浸润及提高壶腹部较小或隐匿病变的检出方面均具有较高价值。更多还原

【Abstract】 ObjectiveTo analyze the imaging features of the periampullary diseases by hypotonic-MRCP and Propeller LAVA multi-phase dynamic enhanced sequence of the 3.0T MR, then study the value and predominance of this technique in the diagnosis and preoperative resection evaluation of periampullary diseases, so as to supply reliable imaging information to further increase the diagnosis and healing rate of periampullary diseases.Materials and Methods43 patients suspected with periampullary diseases were reviewed. All patients underwent routine MRI which include axial T1WI/T2WI and FS-T1WI/T2WI、coronal FIESTA and 2D or 3D hypotonic-MRCP scanning, 37 patients of them underwent Propeller LAVA multi-phase dynamic enhanced scan further. Reformat the original images through MIP and MPR, then draw the time-signal curve. Observe the direct and indirect signs, diagnose the genesis、nature、size and circumscription of the diseases then compared with the clinical and histopathology results. Compare the Propeller LAVA dynamic enhanced scan results to the pre-contrast MRI, use nonparametric rank sum test statistics, while P<0.05 consider it has statistical significance.Results1. For calculus、inflammation and tumor, the sensitivity and specificity of hypotonic- MRCP combine with Propeller LAVA multi-phase dynamic enhanced scan were 100% and 100%、60% and 97.4%、96.7% and 76.9%, the preoperative qualitative accuracy was 100%、93.0% and 90.6%.2. Of all the 30 tumors, 8 carcinomas of ampulla、5 cholangiocarcinomas、12 carcinomas of head of pancreas were diagnosed clearly, the accuracy rating of the tissue origin was 93.3% (28/30 )、90.0% (27/30)、86.7% (26/30) .3. 37 cases underwent Propeller LAVA multi-phase dynamic enhanced scan, the direct sign display rate was 89.2% (33/37), tumor extension diagnose accordance rate was 83.3% (25/30) .The preoperative resection rate of pancreatic carcinoma、cholangiocarcinoma and carcinoma of ampulla were 76.9% (10/13)、85.7% (6/7) and 88.9% (8/9) .4. For the 30 tumor cases, 25 cases were demonstrated clearly by Propeller LAVA multi-phase dynamic enhanced sequence while 2 cases by pre-contrast MRI, there was significant difference of demonstration ability between Propeller LAVA sequence and pre-contrast MRI (P<0.05) .5. As the time-signal curves display cholangiocarcinomas usually achieve the peak value at 40 to50 second, it is not definite for the carcinoma of ampulla which can at the arterial phase or lag period, the enhancement of pancreatic carcinoma is inferior to and later than the two formers .ConclusionHypotonic-MRCP combine with Propeller LAVA multi-phase dynamic enhanced scan can display the direct and indirect sign directly and fully, and have significance in identifying the circumscription of the tumor and its extension, they also have important diagnostic value in smaller periampullary diseases.更多还原