多层螺旋CT对胰周血管的显示研究

目的探讨多层螺旋CT对胰腺周围血管的显示能力。方法将225例接受上腹部增强CT的患者的扫描资料分别按动脉期和门脉期薄层重建,使用容积再现(VR)和多层面容积重建(MPVR)进行血管成像,观察两种成像方式对胰腺周围动脉、静脉的显示情况。结果多层螺旋CT对正常胰腺周围大动脉(腹腔干,肝总动脉,脾动脉,胃十二指肠动脉,肠系膜上动脉)的显示率为100%,对小动脉(胰背动脉,胰横动脉,胰大动脉,胰尾动脉,胰十二指肠上动脉,胰十二指肠下动脉)的显示率为33.8%~96.0%。所显示的胰背动脉起源变异较多,胰背动脉起源于脾动脉,肝总动脉,腹腔干,肠系膜上动脉的比例分别为55.1%、9.7%、10.6%和24.5%。对胰腺周围大静脉(脾静脉,肠系膜上静脉,门静脉主干)的显示率为100%;胰头部小静脉(胰十二指肠上前静脉,胃结肠干及其属支)的显示率为85.3%和77.3%。对于胰腺周围小血管,MPVR较VR具有较强的显示能力。结论多层螺旋CT对胰腺周围大血管具有可靠、稳定的显示率;对胰腺周围小血管也具有一定的显示能力。     

64层螺旋CT肝血管成像的临床研究

目的探讨64层螺旋CT肝脏多期血管成像不同后处理技术显示肝脏血管的能力及其临床应用价值。方法对209例肝脏多期增强扫描患者行肝动脉期、门静脉期双期血管成像,采用最大密度投影(MIP)、容积再现技术(VR)和多平面重组技术(MPR)三种重组方式,分析三种重组方法对肝动脉、门静脉系统、肝静脉以及肝肿瘤血管性病变的显示情况;同期30例患者行肝动脉DSA血管造影,并进行对照观察。结果本组肝动脉变异率为32%;VR与MIP对肝动脉2级以下分支及肿瘤供血动脉的显示无统计学意义(P>0.05),在显示3级以上肝动脉分支及肿瘤血管上有明显差异(P<0.05),MIP优于VR;30例同期行DSA检查的肝癌患者中,MIP与DSA在供血动脉及肿瘤血管的显示上完全一致,对3级以下肝动脉的显示无统计学意义,在4级以上肝动脉的显示上有差异(P<0.05),DSA优于MIP;VR与MIP在显示门静脉及肝静脉分支方面无统计学意义。门静脉有5种变异类型,变异率为27.8%。正常组肝静脉Ⅰ型80例(95%),Ⅱ型4例(5%),7例(8.3%)可见右后下肝静脉。结论64层螺旋CT肝血管成像能更准确、全方位地显示肝血管、肝血管性病变及富血管性肿瘤性病变,可为外科手术及介入术前提供准确信息。VR、MIP与MPR三种重组技术结合使用在肝血管性病变的诊断方面并不亚于DSA。     

多层螺旋CT肝血管成像

目的探讨16层螺旋CT肝脏多期血管成像方法及其临床价值。方法对70例肝脏多期增强扫描患者,行肝动脉期、门静脉期双期血管成像,采用最大密度投影(MIP)、容积再现技术(VRT)、表面遮盖显示(SSD)重建技术,分析三种重建方法对肝动脉、门静脉系统以及肝肿瘤血管性病变(HTVPC)显示情况。结果肝动脉期CT血管造影术(CTA)对二级肝动脉、三级分支以下肝动脉、肿瘤供血动脉及肿瘤血管的显示率分别约90%、69%、90%、69%。MIP与VRT对二级肝动脉分支及肿瘤供血动脉显示的差异无统计学意义(P>0.05),对三级以下肝动脉分支及肿瘤血管的显示有显著性差异(P<0.05),以MIP显示率为高。门静脉期CTA可显示正常肝内门静脉5~6级分支。肝癌肝动脉-门静脉瘘发生率约13.9%,门静脉癌栓发生率约58%,以MIP显示最佳。结论16层螺旋CT肝血管成像是了解肝动脉、门静脉系统状况及肝肿瘤血管性病变的无创性血管成像技术,以MIP及VRT价值较大,可为外科手术及介入术前提供重要信息及指导作用。     

64排螺旋CT血管成像诊断肠系膜上动脉病变

目的:探讨64排螺旋CT血管成像在肠系膜上动脉病变及肠系膜上动脉相关病变中的诊断价值.方法:回顾性分析经CT血管成像诊断肠系膜上动脉病变或肠系膜上动脉相关病变26例的64排螺旋CT资料.使用philips 64排螺旋CT容积扫描,增强扫描于注射对比剂后延迟25 ～ 30 s扫描动脉期,60～ 65s扫描门静脉期.在工作站采用多平面重组(MPR)、最大密度投影(MIP)及容积再现(VR)重组肠系膜上动脉图像,分析64排螺旋CT血管成像对肠系膜上动脉病变和肠系膜上动脉相关病变的诊断价值.结果:26例患者均清晰显示肠系膜上动脉及其分支.26例中发现肠系膜上动脉夹层6例,其中单纯性肠系膜上动脉夹层1例,腹主动脉夹层累及肠系膜上动脉5例,CT表现为肠系膜上动脉内真假腔和低密度的内膜片;肠系膜上动脉缺血性病变16例,CT表现为肠系膜上动脉管壁钙化、管腔狭窄、血栓形成,肠壁增厚、水肿.肠系膜上动脉压迫综合征4例,包括十二指肠瘀滞症3例,CT表现为十二指肠第一、二段扩张,肠系膜上动脉与腹主动脉夹角变小;“胡桃夹”综合征1例,CT表现为左肾静脉受压及远端左肾静脉扩张.结论:64排螺旋CT肠系膜上动脉血管成像可以明确观察肠系膜上动脉各类病变情况及周围血管情况,对肠系膜上动脉病变及肠系膜上动脉相关病变具有广泛的临床应用价值.     

64层螺旋CT对孤立性肠系膜上动脉夹层的诊断价值

目的：探讨64层螺旋CT血管成像在孤立性肠系膜上动脉夹层中的诊断价值。方法：回顾性分析2003年1月—2011年3月在深圳市中医院确诊的11例孤立性肠系膜上动脉夹层病人的64层螺旋CT血管成像影像特征,运用多平面重建、最大密度投影和容积再现等后处理方法显示真腔、假腔和内膜片。结果：64层螺旋CT对11例病人肠系膜上动脉夹层的真腔、假腔和低密度内膜片的显示率均为100%,肠系膜上动脉夹层破口位置距腹主动脉开口平均24.1 mm,累及范围平均48.5 mm,夹层段肠系膜上动脉管腔直径平均增粗12.7 mm。11例病人中,肠系膜上动脉主干血栓形成8例,假腔内血栓形成4例。结论：64层螺旋CT血管成像能清楚显示孤立性肠系膜上动脉夹层病变,可作为该病无创性确诊的金标准。     

64层螺旋CT血管成像评价胰腺直接供血动脉的价值

目的 探讨64 层螺旋CT 血管成像对胰腺直接供血动脉的显示价值.方法 对91 例非胰腺器质性病变行胰腺供血动脉64 层螺旋CT 造影检查,应用腹部容积扫描程序,采用最大密度投影法(MIP)和容积再现(VR)技术获得胰腺直接供血动脉图像,并以DSA 造影结果为金标准进行比对,观察分析MIP、VR 对胰腺直接供血动脉的显示率,并对其显示真实性、可靠性及收益进行评价;采用卡方检验比较两种方法间的差异性.结果 MIP 和VR 对胰腺直接供血动脉的显示率不同,MIP对胰十二指肠上前动脉、胰十二指肠上后动脉、胰十二指肠下前动脉、胰十二指肠下后动脉、胰背动脉、胰横动脉、胰大动脉显示率明显优于VR,经卡方检验,差异有统计学意义(P ＜0.05).MIP 对胰尾动脉显示率与VR 间差异无统计学意义.而且MIP 方法可提高胰腺直接供血动脉显示的敏感度、正确诊断指数和阳性预测值;但其对显示的特异度及阴性预测值与VR 比较差异无统计学意义.结论 64 层螺旋CT 血管成像是一种简便、快速、无创显示胰腺供血动脉检查手段,能够显示胰腺直接供血动脉,并可为临床提供有价值的参考依据;MIP 多角度三维重建能比VR 更准确显示胰腺直接供血动脉解剖结构.     

多层螺旋CT血管成像在肝移植前后的诊断价值

目的评价多层螺旋CT(MSCT)在肝移植手术前后的临床应用价值.方法 7例肝移植患者(男6例,女1例,平均年龄45岁),手术前后1周内均行MSCT肝脏平扫、动态多期增强扫描、3D血管重建、体积测量,CT结果与手术进行对照.结果肝硬化7例,伴有严重肝萎缩2例、小肝癌4例.3D血管成像:100%显示肝总动脉、门静脉、肝静脉起源、长度及主分支;1例肝动脉变异起自肠系膜上动脉,肝总动脉狭窄1例,门静脉狭窄1例,门静脉主干血栓1例,移植后血管并发症1例.术前、术后CT结果均与术中相符.结论 MSCT在肝移植手术前后是一种可行性检查方法,能准确、客观反映肝实质及肝血管情况.     

原发性肝细胞癌的多层CT血管造影表现及临床应用价值

目的探讨原发性肝细胞癌的多层螺旋双期CT血管造影表现及后处理技术.方法所有42例于MX8000 4层螺旋CT机上进行增强扫描,有效层厚3.2 mm,重建间隔1.6 mm,对比剂用量1.5 ml/kg体重,注射速率3 ml/s,延迟时间分别为25 s、50～55 s.进行最大密度投影(MIP)、多平面重组(MPR)、容积再现(VR)处理.结果动脉期显示肿瘤染色者18例,肿瘤血管23例.12例进行了DSA检查,MSCT所显示的肿瘤染色、肿瘤血管及供血动脉的来源与分布与DSA检查一致.门静脉期,检出门静脉瘤栓12例,门静脉闭塞14例,动-静脉分流8例.MIP、MPR及VR有利于检出肝癌的肿瘤染色、肿瘤血管、供血动脉、门静脉闭塞及动-静脉分流.结论 MSCT肝脏双期血管造影可以提供有关肝癌本身、供血动脉及门静脉改变的信息.     

肠系膜上动脉血栓128层螺旋CT血管成像特征及诊断价值分析

目的:分析肠系膜上动脉血栓128层螺旋CT血管成像特征并对CT检查的诊断价值进行探究。方法:回顾性分析2015年5月～2017年12月于我院接受治疗的30例肠系膜上动脉血栓患者128层螺旋CT血管成像资料,探究患者128层螺旋CT血管成像特征。结果:30例患者均存在肠系膜上动脉增粗、血管腔内充盈缺损的情况。其中1例显示腹腔、肠系膜内或者肠壁的气体聚集,2例存在肠系膜水肿,3例存在肠系膜积液,4例患者肠壁明显增厚,6例患者肠系膜不强化,6例患者肠壁变薄,8例患者肠腔扩张、积气或者积液。结论:128层螺旋CT血管成像技术不但能够清楚地反映肠系膜上动脉血栓的血管情况,还具有提示患者肠壁缺血程度的作用,为肠系膜上动脉血栓临床治疗医师治疗方案的制定与实施提供了可靠的影像学支撑,在临床上的应用价值高。     

螺旋CT肝双期扫描及血管三维重建技术对原发性肝癌动静脉瘘的诊断

目的探讨螺旋CT肝双期扫描及血管三维重建对原发性肝癌动静脉瘘(AVS)的诊断价值.方法回顾性分析了21例原发性肝癌并动静脉瘘螺旋CT肝双期扫描及其中9例血管三维重建的表现,血管三维重建方法有2种:表面遮盖成像(SSD)和最大强度投影(MIP).结果肝动脉-门静脉瘘(APVS,中央型)6例,肝动脉-门静脉瘘(APVS,周围型)10例.肝动脉-肝静脉瘘(AHVS)4例,混合型1例.9例肝动脉期血管三维重建均显示强化肝动脉、门静脉影及部分强化正常肝组织,图像直观,立体感强,但不能显示动静脉瘘口.根据肝癌APVS螺旋CT肝双期扫描表现,其程度分为三种:轻度(3例),中度(9例)及重度(4例).结论螺旋CT肝双期扫描及三维重建是诊断与评价肝癌动静脉瘘有效无创伤性方法.     

Involvement of superior mesenteric vessels and portal vein in pancreatic adenocarcinoma: Detection with CT during arterial portography

A prospective study was designed to determine the utility of computed tomography (CT) during arterial portography (CTAP) in the detection of superior mesenteric vessels and portal vein involvement in patients with pancreatic adenocarcinoma. Eighteen patients with adenocarcinoma of the head of the pancreas and eight patients with benign pancreatic disease were investigated with CTAP, dynamic contrast-enhanced CT, and angiography. Appropriate review was made to determine presence or absence of superior mesenteric vessels and portal vein involvement. Final diagnosis was obtained in all cases by surgical explorations. The overall accuracy rate for detecting or excluding superior mesenteric vessels and portal vein involvement was 96% (25 of 26 patients) with CTAP, 88% (23 of 26 patients) with dynamic contrast-enhanced CT, and 85% (22 of 26 patients) with angiography. No statistically significant difference in accuracy was found among the three techniques. Our results suggest that the use of CTAP is not indicated in the preoperative detection of superior mesenteric vessels and portal vein involvement in patients with pancreatic adenocarcinoma.     

螺旋CT血管造影评价胰腺癌可切除性的意义

目的探讨螺旋CT血管造影（SCTA）诊断胰腺癌胰周血管侵犯及评价可切除性的价值。方法10例疑有局部浸润的胰腺癌患者术前行横断面CT及螺旋CT血管造影检查。比较分析SCTA与横断面CT诊断肿瘤侵犯胰周血管情况以及评价肿瘤可切除性。结果SCTA诊断胰周血管侵犯的敏感度、阴性预测值（100％、100％）高于横断面CT（81．8％、92．6％）。两者差异有统计学意义（P〈0．05）。SCTA术前评价胰腺癌可切除性的阳性预测值高于横断面CT。结论SCTA可精确地诊断胰腺癌侵犯胰周血管的情况，术前可准确评价胰腺癌可切除性。     

CT depiction of small arteries in the pancreatic head: assessment using coronal reformatted images with 16-channel multislice CT

Background To assess the capabilities of 16-channel multislice CT in acquiring almost exclusively arterial-phase images of the pancreas and depicting small pancreatic arteries in coronal reformatted images. Materials and methods In 45 consecutive patients, arterial-phase contrast enhancement was measured in the aorta and its branches, portal venous system, and pancreas. Coronal reformatted images of 1.2- or 1.3-mm slice thickness at 0.8- or 0.9-mm intervals were generated from axial images acquired with 0.5-mm collimation. Two radiologists evaluated the quality of imaging in the arterial phase and the visibility of the pancreatic arteries in coronal reformatted images. Results Mean enhancement in the aorta and its branches was greater than 300 HU, while that in the portal venous system and pancreas was less than 100 HU. The images were judged to be suitable for delineating the pancreatic arteries in all patients. The following arteries were visualized: anterior superior pancreaticoduodenal (39 patients), posterior superior pancreaticoduodenal (41), anterior inferior pancreaticoduodenal (39), posterior inferior pancreaticoduodenal (33), dorsal pancreatic (42), its right branch (34), and transverse pancreatic (37). Conclusion Multislice CT can depict small pancreatic arteries using coronal reformatted images generated from almost exclusively arterial-phase axial images acquired with 0.5-mm collimation.     

Arterial supply to the pancreas; variations and cross-sectional anatomy

The pancreas has complex arterial supplies. Therefore, special attention should be paid in pancreatic arterial intervention for patients with acute pancreatitis and pancreatic carcinomas. Knowledge of pancreatic arterial anatomy and arterial territory is important not only to perform pancreatic arterial intervention, but to read the pancreatic angiography and cross-sectional image. We reviewed 226 selective abdominal angiography and CT scans during selective arteriography (CTA) of common hepatic artery, superior mesenteric artery, splenic artery, or peripancreatic arteries including posterior superior pancreaticoduodenal artery, anterior superior pancreaticoduodenal artery, inferior pancreaticoduodenal artery, and dorsal pancreatic artery. CTA images were evaluated to clarify the cross-sectional anatomy of the pancreatic arterial territory. Variations of the peripancreatic arteries were also investigated. In this exhibit, schemes and illustrative cases demonstrate pancreatic arterial territory and variations.     

State-of-the-art ultrasonography is as accurate as helical computed tomography and computed tomographic angiography for detecting unresectable periampullary cancer.

OBJECTIVE: To compare the ability of state-of-the-art ultrasonography with that of helical computed tomography and computed tomographic angiography in detecting unresectable periampullary cancer. In most patients periampullary cancer is unresectable because of either distant metastasis or local vascular involvement. The advent of gray scale and color Doppler ultrasonography has improved the ability of ultrasonography to detect vascular involvement. METHODS: Twenty-three consecutive patients with periampullary cancer were enrolled for prospective staging of their disease by comparing helical computed tomography and computed tomographic angiography with gray scale and color Doppler ultrasonography of the abdomen. Portal vein, superior mesenteric vein, splenic vein, and superior mesenteric artery involvement was graded 0 to 4, grade 0 being no vascular involvement and grade 4 being total occlusion of the vessel. Agreement between ultrasonography and computed tomographic angiography for determining vascular involvement was measured by chi2 analysis. RESULTS: Two patients (9%) were excluded because excessive overlying bowel gas hampered the ability of ultrasonography to visualize the pancreas. For the remaining 21 patients, there was significant agreement between ultrasonography and computed tomographic angiography for detecting vascular involvement in all vessels (P < .001; portal vein, kappa = 0.67; superior mesenteric vein, kappa = 0.67; splenic vein, kappa = 0.85; and superior mesenteric artery, kappa = 0.59). Ultrasonography was in agreement with computed tomographic angiography in all cases of unresectability. Both modalities were equally poor in preoperatively showing lymphadenopathy and metastases. CONCLUSIONS: Provided that there is adequate visualization on ultrasonography of the head of the pancreas in the periampullary region, then state-of-the-art gray scale and color Doppler ultrasonography are as accurate as helical computed tomography and computed tomographic angiography for detecting the unresectability of periampullary cancer. If performed as the initial investigation and the region of the pancreatic head is clearly shown, and if vascular encasement or occlusion or distant metastasis is identified, further investigations are unnecessary.     

胰腺癌CT征象探讨

目的 对胰腺癌的CT征象进行探讨。方法 收集经手术病理证实的胰腺癌18例,其中胰头癌13例,胰体癌3例,胰尾癌2例,就其CT征象进行分析,同时又收集手术病理证实的壶腹癌7例,十二指肠乳头癌5例,胆总管远端癌4例,胰头部炎性肿块3例作为鉴别诊断,全部病例均采用型高分辨率CT机作增强前后扫描,对兴趣区作3－5mm薄层和动态扫描,并分别摄取动脉期及静脉期相。结果 胰腺肿块呈低密度,胰头静脉弓扩大,胰后脂肪间隙模糊,肿块远端的胰腺组织不同程度稀疏,萎缩,肠系膜上动脉增粗,胆总管远端和主胰管远端间距分离,为胰腺癌较具特征的表现,结论 高分辨率CT薄层和动态扫描是发现胰腺癌的有效方法。     

MR angiography: noninvasive vascular imaging of the abdomen

Magnetic resonance angiography (MRA) has been used to image abdominal vessels less frequently than renal arteries. Until the use of fast contrast-enhanced (CE) techniques, an important limitation was the acquisition time of phase-contrast or time-of-flight imaging and, consequently, the creation of motion artifacts. Recent advances in MRA technology have shortened acquisition times, so it is now possible to obtain successive images in the arterial and then the portal phase. MRA can be used as an adjunct to any MR examination to assess, e.g., the arterial feeding of hepatocellular carcinoma, the encasement of arteries, and segmental portal thrombosis in pancreatic carcinoma. However, MRA has been used mainly to study chronic mesenteric ischemia, portal vein diseases, and complications from liver transplantation. The portal venous system is exquisitely portrayed with this method; MRA is as accurate as digital subtraction angiography (DSA) in the diagnosis of portal vein diseases. Acute mesenteric ischemia is an emergency in which computed tomography is the most appropriate imaging modality. Conversely, chronic mesenteric ischemia is best examined with CE-MRA, which is almost as accurate as DSA. CE-MRA is superior to DSA for the simultaneous exploration of the aorta, renal arteries, and iliac arteries, thereby providing a panoramic view of abdominal vascular involvement. MRA can be coupled with measurements of flow. With this functional approach, MRA is the only modality that can completely assess vascular diseases of the abdomen.     

Sonography versus helical CT in identification and staging of pancreatic ductal adenocarcinoma

PURPOSE: The aim of this prospective study was to compare sonography with helical CT in the identification and staging of ductal adenocarcinoma of the pancreas. METHODS: Sixty-four patients with histopathologically proven pancreatic ductal adenocarcinoma underwent both sonography and helical CT at our hospital between November 1, 2000, and October 31, 2001. These diagnostic imaging examinations were performed by 2 independent radiologists who were unaware of the findings of any other imaging or histopathologic examination and who assessed each case for the presence of tumor, involvement of peripancreatic vessels, the presence of metastases in the liver, and the resectability of the tumor. In the patients who underwent subsequent laparotomy, imaging-based diagnoses of overall resectability and vascular involvement were compared with surgical findings, which were considered the gold standard. Imaging-based diagnoses for the presence of hepatic metastases were compared with the findings of intraoperative sonography in patients who underwent radical resection and with the surgical findings in the patients who underwent palliative surgery; the operative findings were considered the gold standard. RESULTS: In the identification of pancreatic adenocarcinoma, sonography was more accurate (61 of 64 tumors, 95.3%) than helical CT was (57 of 64 tumors, 89.1%). In the overall prediction of resectability among the 43 patients who underwent laparotomy, sonography (81.4%) was less accurate than CT was (86.0%). In diagnosing involvement of the superior mesenteric artery, sonography (95.3%) was more accurate than CT (88.4%). The 2 methods were equally accurate in diagnosing hepatic metastases (86.0%) and involvement of the celiac trunk (100%) and the superior mesenteric vein (88.4%), but sonography was less accurate than CT for diagnosing involvement of the common hepatic artery (90.7% versus 95.3%, respectively) and portal vein (88.4% versus 93.0%, respectively). CONCLUSIONS: Sonography is more reliable than CT in identifying pancreatic adenocarcinoma, and its accuracy in staging is similar to that of CT.