胆囊癌腹部淋巴结转移的分布特征及CT和MR影像表现

目的探讨胆囊癌腹部淋巴结转移的分布特征及其相关CT和MR影像表现。方法对23例患者采用CT和MR扫描,观察中上腹部区域淋巴结大小、位置及分布情况。结果本组23例患者中壁厚型9例,结节型7例,肿块型7例。其中10例患者存在一个或多个淋巴结中心坏死,12例患者存在淋巴结融合现象。未坏死淋巴结呈现均匀中度强化,而发生坏死的淋巴结边缘部分存在明显强化,而在中心部分则呈现不强化,CT检查结果呈现低密度,MR T1WI图像上表现为低信号,而T2WI则为高信号。根据患者的CT和MR检查所反映的肿大淋巴结结合文献将其淋巴结分为四组,即门腔间隙-胰后组、腹腔动脉干组、肠系膜血管组、腹主动脉组。结论 CT和MR影像检查可以准确显示胆囊癌淋巴结的转移情况,加深对胆囊癌影像学表现的全面认识,胆囊癌腹部淋巴结转移主要分布在门腔间隙.胰头后方、腹腔动脉干周围、肠系膜上动脉周围以及腹主动脉周围。     

腹腔及腹膜后间隙淋巴结结核的多层螺旋CT强化特征

目的研究腹腔及腹膜后间隙淋巴结结核的多层螺旋CT强化特征,以提高该疾病的影像诊断水平。方法收集本院经临床病理证实的腹部淋巴结结核19例,在多层螺旋CT强化图像上,观察受累淋巴结的大小、形态、密度、强化类型、优势解剖分布以及淋巴结外器官病变的强化特征。结果94.7%淋巴结结核呈典型的环状强化,仅5.3%增大的淋巴结呈均匀强化。腹部淋巴结结核常优势地累及肠系膜(73.7%)、门腔间隙(63.2%)、肝十二指肠韧带(57.9%)、肝胃韧带(47.4%)和腹主动脉周围上部淋巴结(47.4%)。9例(47.4%)脾增大,其中5例(26.3%)脾内有多发低密度灶,病灶周边强化;6例(31.5%)腹腔积液;3例(15.8%)大网膜、肠系膜和壁层腹膜广泛结节样增厚。结论结核累及腹腔及腹膜后间隙淋巴结的多层螺旋CT强化具有一定特征。     

胰腺癌螺旋CT动态增强扫描征象的探讨

目的 :对胰腺癌螺旋CT动态增强扫描征象进行探讨。方法 :病理证实胰腺癌 37例 ,胰头癌 2 8例 ,胰体癌 5例 ,胰尾癌 4例。其中男 30例 ,女 7例。给予高分辨率螺旋CT动态增强扫描。结果 :胰腺癌主要征象 :胰腺肿块 ,在动脉期 (胰腺期 )表现为明显的低密度灶 ,胰腺肿块低密度灶与正常胰腺组织密度差有显著差异。其他征象 :胰管和胆管扩张 ;胰周脂肪间隙模糊 ;胰周血管变形和周围淋巴结肿大等。结论 :螺旋CT动态增强扫描对检出胰腺癌是非常有效的方法。     

胰腺癌胰外神经侵犯的CT诊断

目的:研究CT对胰腺癌胰外神经侵犯的诊断价值.方法:32例外科手术和病理证实的胰腺癌,术前1个月内均行螺旋CT检查.回顾性分析肿瘤大小、胰周血管侵犯、淋巴结转移和胰外神经侵犯情况,根据胰周腹腔神经丛主干及腹腔神经节周围软组织改变确定胰外神经侵犯的CT征象.以病理结果为标准,分析CT对胰外神经侵犯的准确性、特异性和敏感性,以及胰外神经侵犯与肿瘤大小、胰周血管侵犯、淋巴结转移的相关性.结果:32例胰腺癌,病理发现胰内和(或)胰周神经侵犯27例(84.4%),胰内合并胰周神经侵犯24例(75%),单纯胰内神经侵犯3例(9.4%).CT发现22例(68.8%)胰外神经侵犯,CT诊断胰腺癌胰外神经侵犯的敏感性、特异性、准确性分别为87.0%、77.8%、84.4%.胰外神经侵犯与肿瘤大小(Spearman,P=0.428>0.05)、淋巴结转移(Fisher's exact test,P=0.506>0.05)无相关性,与血管侵犯(Spearman,r=0.54,P=0.001<0.05)具有相关性.结论:CT对胰腺癌胰外神经侵犯有较高的预测率.胰周间隙密度增高,出现条带状致密影,或出现不规则软组织块影提示已有肿瘤的神经侵犯.     

胰头部占位性病变的鉴别诊断

作者分析了CT 对判断胰头占位性病变的可能性与局限性。作者指出CT 的局限性有:1.诊断胰头部恶性肿瘤淋巴结转移首先是胰十二指肠前或后淋巴结,可使胰头与十二指肠之间的角阻塞,CT无法确切鉴别肿瘤是否直接侵入了十二指肠,但这种鉴别将影响手术指征,其次的淋巴结转移为腹腔动脉和肠系膜上动脉开口淋巴结转移,如果CT 发现此征象为不能手术切除的指征,这时显示腹腔动脉主干结节状增粗,或者肠系膜上动脉粗大,这可能为淋巴管浸润或淋巴管周围组织水肿,24%的胰     

胰周区域淋巴结CT表现及其解剖、病理基础

本文所述胰周淋巴结主要位于胰周围、肠系膜根部、门腔间隙和脾门。常见的淋巴结病变包括结核、淋巴瘤及转移性肿瘤。淋巴结结核CT强化表现为淋巴结增大，呈周边强化，易形成多房样征象。87．5％霍奇金病和70％非霍金奇淋巴瘤淋巴结增大呈均匀强化，少数呈均匀强化并坏死，解剖上优势地累及腹主动脉周围上、下部淋巴结。转移性肿瘤结增大强化特征与原发灶的细胞类以及有无化疗等相关，其优势解剖分布取决于原发肿瘤的淋巴引流途径。     

肝内胆管细胞癌淋巴结转移的CT特征分析

目的 探讨肝内胆管细胞癌腹部淋巴结转移的CT表现.方法 回顾性分析46例经手术与病理证实的肝内胆管细胞癌患者的螺旋CT表现.重点观察转移淋巴结的分布情况、大小、密度及强化表现.结果 46例病人中22例出现转移(47.8%),以肝十二指肠韧带组淋巴结转移发生率最高(90.9%),其次为贲门-胃小弯-胃左淋巴结组、胰后组、腹主动脉旁组、肝总动脉组、腹腔干组,分别为36.4%、36.4%、27.3%、18.2%、13.6%;转移淋巴结呈等、略低密度,短径≥2.5 cm的淋巴结容易出现坏死,增强扫描淋巴结轻、中度强化,坏死部分不强化;肿瘤分化程度与淋巴结转移有明显相关性(X~2=5.601,P<0.05).结论 CT扫描可以准确观察肝内胆管细胞癌淋巴结的转移情况.     

胰腺癌CT表现与手术病理及D2-40表达的相关性研究

目的:探讨胰腺癌CT征象与手术病理及癌组织淋巴管生成之间的关系.方法:对33例胰腺癌患者(男24例,女9例,年龄38～79岁)行CT平扫及动脉期、门静脉期、延迟期增强扫描,分析胰腺癌的病灶大小、密度、强化程度、对胰周组织的侵犯、胰胆管扩张,胰周淋巴结等CT征象,所有病例均行手术切除,术后标本采用单克隆抗体D2-40免疫组化方法检测肿瘤组织中的瘤周和瘤内淋巴管密度(pLVD,iLVD).使用Kappa检验和t检验统计学方法将CT表现与病理结果、淋巴管密度进行对照.结果:CT诊断胰腺癌病灶的大小、胰周组织侵犯、胰周淋巴结转移与手术病理结果一致性良好(P＜0.05),CT对胰腺癌分期的准确性为78.79％(26/33).CT征象中胰周组织侵犯、胰周淋巴结肿大、分期与胰腺癌pLVD有关(P＜0.05).与iLVD无关(P＞0.05);CT征象中病灶大小、密度、胰胆管扩张、病灶强化程度则与pLVD、iLVD均无关(P＞0.05).结论:CT能较可靠地反映胰腺癌的病理学特征;胰周组织侵犯、胰周淋巴结肿大等CT征象与胰腺癌组织的淋巴管密度有关,可一定程度上揭示胰腺癌组织的淋巴管生成、淋巴结转移及判断预后.     

腹主动脉及其分支的SCTA技术与临床应用

随着螺旋CT的问世，螺旋CT血管造影(Spiral Computed tomography angiography SCTA)已成为现实。它扫描速度快，可在一次屏气的30秒内完成扫描，尤其在胸、腹部避免了呼吸的影响，并且系少剖伤检查，因而具有广阔的应用前景。目前．腹部动脉的SCTA主要用于检查与评价：①腹主动脉及其主要分支如肾动脉、腹腔动脉、肠系膜上动脉车身的病变与变异；②胰、脾、肝周围血管受肿瘤侵犯的情况。     

原发性肝细胞性肝癌局部淋巴结转移的螺旋CT表现

目的 :探讨原发性肝细胞性肝癌 (HCC)局部淋巴结转移的CT表现及病灶的大小、边缘形态与出现局部淋巴结肿大的关系。方法 :盲法下分析 162例HCC病灶的CT扫描影像。结果 :162例病灶中 48例 (占 2 9.63 %)出现局部淋巴结转移。其中肝门组、门腔间隙组以及腹主动脉组最为常见 ,其出现概率分别为 12 .96%,14 .81%,11.73 %。局部淋巴结转移出现概率与病灶大小及边缘形态有统计学意义 (P <0 .0 5 )。结论 :HCC发生局部淋巴结转移的概率为 2 9.63 %。HCC最主要的淋巴转移途径为肝内深、浅淋巴管经肝门淋巴结、门腔间隙淋巴结、腹腔干旁淋巴结至腹主动脉旁淋巴结 ,并常表现为多组、跳跃式淋巴结转移。发生局部淋巴结转移的HCC更容易出现在体积较大和无包膜型HCC中。HCC的CT分型能够反映其病理演变。     

胰腺癌血管侵犯的不同CT诊断标准的研究

目的:研究胰腺癌血管侵犯的不同CT诊断标准的优劣。材料和方法:回顾性收集我院经多层螺旋CT三期动态增强扫描并经手术病理证实为胰腺导管细胞癌的36例患者。CT轴位图像结合CTA(以MIP和VR方法重建)以及多平面重建(MPR)分别对这些血管以Loyer和Lu血管分级CT标准进行分级,并和手术结果进行对照,分别作出受试者工作特性曲线(ROC),比较曲线下面积的差异。另外,运用Lu的CT诊断标准分别评价胰周动脉和静脉受侵的准确性、灵敏度、特异度、阳性预测值、阴性预测值、Youden指数,研究Lu的CT诊断标准对动静脉分级的差异。结果:Loyer和Lu的CT诊断标准所得的灵敏度、特异度分别为84.5%、86.0%、81.4%、91.8%,两个诊断标准的ROC曲线下面积分别为0.886、0.912,经统计学检验无明显差异。应用Lu的CT诊断标准,胰周动静脉受侵的阳性预测值分别为57.1%和71.0%。结论:分别以Loyer和Lu血管分级CT标准对胰腺癌胰周血管侵犯进行分级,两者的诊断价值相同,Lu的CT诊断标准的最佳诊断分界点应在90°-180°之间,此外,它对胰周动脉的价值要比静脉差。     

螺旋CT增强扫描在胰头癌诊断中的价值

目的 :探讨螺旋CT增强扫描在胰头癌诊断中的意义及其不同CT征象的诊断价值。方法 :搜集 45例经临床、内镜超声等诊断或经手术病理证实的胰头癌病例 ,回顾性分析其螺旋CT成像中各种特异性表现的诊断敏感性 ,总结其CT扫描技术要点。结果 :螺旋CT增强扫描显示胰头癌最常见的CT征象有相对低密度瘤灶 ( 10 0 % )、胰周血管受侵( 86.7% )、胰头、体尾部比例失调 ( >1.2 ,占 80 .0 % )、胆总管扩张伴下端截断征 ( 4 6.7% )、双管征 ( 3 3 .3 % )、淋巴及脏器转移 ( 2 0 .0 % )等 ,螺旋CT动脉期 ( 2 5～ 3 0s)、门静脉期 ( 5 0～ 65s)动态双期扫描的诊断价值最大。结论 :采用适时的螺旋CT增强扫描时间能更好显示胰头癌的CT特征 ;综合分析各种CT征象对诊断有很大价值。     

胰腺癌侵犯胰周主要血管的CT表现分析

目 的分析多层螺旋CT(MSCT)胰腺检查，胰腺癌侵及胰周主要动、静脉的不同CT表现特征。方法 MSCT诊断胰腺癌68例患者中，33例行手术治疗(其中12例行胰十二指肠切除术，21例剖腹探查发现不可切除)，病理结果均证实为胰腺导管细胞癌。术中由手术者仔细探查胰周主要血管[肠系膜上动脉(SMA)、腹腔干(CA)、肝动脉(HA)、肠系膜上静脉(SMV)及门静脉主干(PV)]。结果 165支受检血管中，手术探查发现103支血管未受侵犯，其余62支血管受侵，MSCT术前检查，8．1％(5／62)受侵血管误判为未受侵犯(假阴性)。其余受侵的胰周主要动、静脉(57支)具有不同的CT表现特征：胰周主要动脉受侵时，均被肿瘤包绕大于管周的1／2或完全包埋于肿瘤中。胰周主要静脉受侵时，部分静脉血管被肿瘤包绕小于管周的1／2：SMV为4支(4／17)，PV为2支(2／13)，但同时均出现管壁受浸润或管腔狭窄或管腔形态改变；胰周静脉受侵犯时出现管腔狭窄或闭塞的机会较胰周动脉大：SMV为11支(11／17)，PV为12支(12／13)，而CA为3支(3／8)，HA为4支(4／7)，SMA为4支(4／12)；胰周静脉受侵犯时管壁呈浸润性改变的比例较胰周动脉高：SMV为11支(11／17)，PV为7支(7／13)，而CA为3支(3／8)，HA为2支(2／7)，SMA为6支(6／12)。结论 胰周动、静脉受侵及时，其CT表现具有不同特征。     

Computed tomography of peripancreatic fat planes

Obliteration of peripancreatic fat planes usually is considered an indicator of peripancreatic tumour infiltration in the presence of a malignant mass, or of inflammation of peripancreatic tissues in patients with pancreatitis. However, absence of peripancreatic fat planes also may be found in patients without evidence of pancreatic disease. Hence, CT scans of 125 patients without clinical or computed tomographic evidence of pancreatic disease were evaluated to assess normal variations in the anatomy of the pancreas and its relation to surrounding vessels and bowel loops. The fat plane separating the superior mesenteric artery from the pancreas was preserved in 100% of patients. Conversely, fat planes between the pancreas and the superior mesenteric vein, inferior vena cava, and adjacent bowel loops were partially or totally obliterated in 13% to 50% of patients. It is concluded that the absence of fat around the superior mesenteric artery is highly suggestive of pathologic changes of the pancreas, while the lack of fat planes between the pancreas and other splanchnic vessels or bowel loops frequently is normal, and therefore, is an unreliable sign of pancreatic disease. The applications of these findings to the assessment of tumour resectability by CT, and to CT scanning techniques, are discussed.     

CT assessment of the inferior peripancreatic veins: clinical significance

OBJECTIVE: The purpose of this study was to evaluate and clarify the clinical significance of CT scans of the inferior peripancreatic veins. MATERIALS AND METHODS: Forty-three patients with suspected pancreatic disease underwent three-phase helical CT (collimation, 5 mm; reconstruction, 2.5 mm; scan delay, 30, 60, and 150 sec). The frequency of visualization on CT of the anterior and posterior inferior pancreaticoduodenal veins, inferior pancreaticoduodenal vein, and first jejunal trunk was assessed and correlated with angiographic and pathologic findings. RESULTS: The frequency of visualization of normal inferior peripancreatic veins in patients (n = 22) with a normal portomesenteric vein was 36% for the anteroinferior pancreaticoduodenal vein, 36% for the posteroinferior pancreaticoduodenal vein, 59% for the inferior pancreaticoduodenal vein, and 100% for the first jejunal trunk. The smaller inferior peripancreatic veins were frequently not visualized when normal. In patients (n = 13) with pancreatic carcinoma involving the portosuperior mesenteric vein, all of the inferior peripancreatic veins were dilated and easily recognizable. When the tumor did not involve the portosuperior mesenteric vein but did involve the anteroinferior pancreaticoduodenal, posteroinferior pancreaticoduodenal, and inferior pancreaticoduodenal veins (n = 8), some of the other peripancreatic veins (first jejunal trunk, anterior and posterior superior pancreaticoduodenal veins, and gastrocolic trunk) were dilated. Dilatation indicated tumor extension to the third portion of the duodenum. In patients (n = 7) with involvement of the inferior pancreaticoduodenal vein, the first jejunal trunk, or both without the involvement of the portosuperior mesenteric vein, dilatation of the other peripancreatic veins (anteroinferior pancreaticoduodenal vein, posteroinferior pancreaticoduodenal vein, anterosuperior pancreaticoduodenal vein, posterosuperior pancreaticoduodenal vein, and gastrocolic trunk) indicated tumor invasion of only the second portion of the extrapancreatic nerve plexus (n = 4) and tumor invasion of both the second portion of the extrapancreatic nerve and the mesenteric root (n = 3). CONCLUSION: Dilatation of peripancreatic veins with nonvisualization of inferior peripancreatic veins suggests tumor invasion of peripancreatic tissue.     

Multi--detector row helical CT of the pancreas: effect of contrast-enhanced multiphasic imaging on enhancement of the pancreas, peripancreatic vasculature, and pancreatic adenocarcinoma.

PURPOSE: To determine the optimal phase for enhancement of the normal pancreas and peripancreatic vasculature and the maximal tumor-to-pancreatic parenchymal enhancement difference by using multiphase, contrast material-enhanced, multi-detector row helical computed tomography (CT). MATERIALS AND METHODS: Forty-nine patients with a normal-appearing pancreas but suspected of having pancreatic abnormality and 28 patients with proved pancreatic adenocarcinoma underwent multiphase, contrast-enhanced, multi-detector row CT during the arterial phase (AP), pancreatic parenchymal phase (PPP), and portal venous phase (PVP). Attenuation values of the normal pancreas, pancreatic adenocarcinoma, celiac and superior mesenteric arteries, and superior mesenteric and portal veins were measured during all three imaging phases. Quantitative analysis of these measurements and subjective qualitative analysis of tumor conspicuity were performed. RESULTS: Maximal enhancement of the normal pancreatic parenchyma occurred during the PPP. Maximal tumor-to-parenchyma attenuation differences during the PPP and PVP were equivalent but greater than that during the AP. Subjective analysis revealed that tumor conspicuity during the PPP and PVP was equivalent but superior to that during the AP. Maximal arterial enhancement was seen during the PPP, and maximal venous enhancement was seen during the PVP. CONCLUSION: A combination of PPP and PVP imaging is sufficient for detection of pancreatic adenocarcinoma, because it provides maximal pancreatic parenchymal and peripancreatic vascular enhancement. AP imaging can be reserved for patients in whom CT angiography is required.     

Peripancreatic fat necrosis mimicking pancreatic cancer

A case of peripancreatic fat necrosis, after an episode of acute pancreatitis, which mimicked pancreatic cancer with lymph node metastases, is presented. We describe the imaging findings with helical CT scanning and with unenhanced and mangafodipir-enhanced MR imaging, with special emphasis on the differential diagnoses. Received: 8 May 2000 Revised: 17 August 2000 Accepted: 18 August 2000     

CT in the evaluation of carcinoma of the pancreas

The routine use of CT has given a great contribution both to the diagnosis and to the evaluation of the extent of pancreatic carcinomas. Forty-three patients clinically suspected of pancreatic carcinoma were examined with CT. Forty of them underwent surgical control. This study was conducted to evaluate the role of CT in the diagnosing and staging of pancreatic carcinomas. 31/43 neoplasms were identified, with a diagnostic accuracy of 90%. CT was extremely accurate in the demonstration of late metastases, while it had lower accuracy in assessing the involvement of lymph nodes and peripancreatic vessels (60-70%). CT proved to be extremely useful in diagnosing pancreatic carcinomas, for it allows the detection of masses associated with Wirsung's duct dilatation and atrophy, which are a highly pathognomonic sign of pancreatic neoplasms. Moreover, CT proved useful in the staging, by assessing the presence of lymph nodes and metastases.     

胰腺癌与慢性胰腺炎的CT诊断

目的：提高对胰腺疾病的ＣＴ诊断水平。材料与方法：作者根据被证实的１５４例胰腺癌、慢性胰腺炎及其他疑误诊为前两种疾病病例的ＣＴ资料，对４５个项目，３８个ＣＴ征象进行观测、统计与分析。结果：二者诊断与鉴别的主要征象是：（１）病变区胰腺局限或弥漫肿大与密度异常；（２）有无扩张的胆总管（或壶腹）突然性狭窄截断与胰周大血管被包埋、管径增粗、癌栓，腹部淋巴结肿大、肝转移；（３）有无沿胰管走向分布的钙化与扩张胰管，扩张胰管的形态与贯通病变区的情况；（４）胰腺囊肿的发生频率、部位，与胰腺的轮廓关系。结论：根据前述要点，参考其他征象，密切结合临床，ＣＴ诊断正确率达９０％以上。     

Pancreatic adenocarcinoma: signs of vascular invasion determined by multi-detector row CT

The purpose of this study was to analyse multi-detector row CT (MDCT) signs of peripancreatic arterial and venous invasion in pancreatic carcinoma. Among 101 patients with pancreatic carcinoma examined by MDCT, 54 candidates for surgery were pre-operatively evaluated for vascular invasion based on MDCT signs. The peripancreatic major vessels (including superior mesenteric artery, coeliac artery, common hepatic artery, superior mesenteric vein and portal vein) were examined carefully by surgeons during the operation. At surgical exploration, 78 of 224 vessels were invaded by tumour. The invaded peripancreatic major arteries (n = 29) and veins (n = 49) presented different MDCT signs: 43% of invaded veins (18/42, except for 7 occluded veins) were surrounded by tumour less than 50% of the vessel circumference compared with 97% (28/29) of the invaded arteries, which were surrounded by tumour more than 50% of the vessel circumference or were embedded in tumour (p<0.001). 69% (34/49) of the invaded veins had vascular stenosis or obliteration, compared with 41% (12/29) of the invaded arteries (p<0.05). Irregularity of the vein wall, 74% (31/42, except for 7 occluded veins); occurred more often than that of the artery wall, 45% (13/29) (p<0.05). In conclusion, the MDCT signs of peripancreatic arterial and venous invasion have different characteristics, which should be considered in pre-operative evaluation.