正常胃的MRI表现与扫描技术

目的：研究正常胃的MRI表现和扫描技术。方法：在胃不同充盈状态下，采用单次屏气快速扫描序列，共进行72人次MRI平扫和7次增强检查，分析正常胃的MRI表现和图像质量。结果：按充盈程度不同，胃壁形态可分为扩张不良，适度扩张、充分扩张3型表现。MRI能较好显示胃及其与邻近器官的关系。胃壁厚度平均值在适度扩张下为2．7mm，在充分扩张下为2.4.T2WI图像均无运动伪影，79％的T1WI图像在使用解痉剂后无运动伪影。结论：采用单次屏气快速扫描序列，MRI能获得满意的胃部图像，较好显示胃及其与邻近解剖关系。     

正常胃CT应用解剖和表现

目的：正确认识胃的ＣＴ解剖和表现，了解正常成人的胃壁厚度，确立正常和异常的标准。材料与方法：我们用胃模型、离体和在体标本进行了正常胃ＣＴ应用解剖的研究，对３组共８０例正常成人服用不同量的水行或不行低张药注射后进行ＣＴ扫描和测量胃壁厚度及值检验。结果：横断面ＣＴ图可以清楚的显示胃的解剖区域、前后壁和大小弯等，尤其与邻近器官的毗邻关系非常清楚。正常成人胃壁厚度与服水量及胃的扩张程度关系密切，在不同部位     

螺旋CT增强扫描在诊断胃癌中的价值（附25例分析）

目的：探讨螺旋CT增强扫描对胃癌的诊断价值。方法：例胃癌患者口服800-1200ml水对比剂，肌注654-2注射液10mg，静脉注射80-100ml造影剂作螺旋CT胃客积扫描。结果：25例采用口服水低张静脉增强螺旋CT胃容积扫描见胃腔充盈及扩张度良好，清晰显示肿瘤大小、形态与邻近组织关系，胃癌表现为局限性和广泛性胃壁增厚，肿瘤向腔内、腔外生长形成不规则隆起的软组织肿块。结论：螺旋CT增强扫描可以诊断胃癌和了解胃周围淋巴结肿大和邻近器官有无转移，对手术具有重要的指导意义。     

口服脂肪密度造影剂后胃壁的CT观察

目的：对口服脂肪密度造影剂后，行上腹部CT扫描的正常人胃体部及贲门部胃壁的形态进行观察并通过测量获得胃壁的正常厚度。材料与方法；受检正常人102例，口服脂肪密度造影剂为15％花生油乳剂，经常规上腹部CT扫描后，观察胃体部及贲门部胃壁形态并进行测量，经统计学处理得出平均值。结果：正常人胃体部壁形态光整，厚度在0．2－1．0cm范围之内，中位数0．35cm，贲门部胃壁较胃体部略厚，呈三角形或折角状，厚度在0．2－1．1cm之间，平均值为0．58cm。结论：正常人胃体部及贲门部胃壁光滑，规整、厚度分别应在1．0cm及1．2cm以下。     

多层螺旋CT对胃癌及肿瘤血供的应用价值分析

目的：探讨多层螺旋CT（MSCT）增强扫描及血管造影在胃癌诊断及肿瘤血供中的应用价值。方法收集近2年在我院经手术病理证实为胃癌38例患者的64层螺旋CT双期增强扫描及血管造影图像,分析胃癌的CT征象及CT血管造影对胃癌供血的显示,与术中所见及术后病理进行对照。结果64层螺旋CT双期增强扫描诊断胃癌,显示胃壁厚度、胃壁外软组织肿块及胃壁溃疡大小与术后证实差异无统计学意义;病理诊断为低分化腺癌的胃壁厚度、胃壁外软组织肿块及胃壁溃疡大小、区域淋巴结转移率与中分化腺癌的差异有统计学意义。血管造影腹腔干、肝固有动脉,胃左动脉、胃右动脉及胃网膜右动脉在容积再现（VR）上能够很清晰地显示;最大密度投影（MIP）显示细小血管较好,但是它在表现三维空间关系上不如VR。结论 MSCT双期增强扫描对胃癌有较高的诊断价值,血管造影在肿瘤血供显示有较高价值。     

螺旋CT在胃分区及胃壁厚度测量中的价值

目的应用SCT成像技术对胃进行分区并对其胃壁厚度进行测量,旨在制定各区胃壁厚度的正常值.方法对50例正常成年人应用SCT进行胃区扫描,并对其中的28例胃区进行双期强化扫描,按胃的解剖分区法对胃的MPR冠状重建图像进行分区,并应用光标分别测量各区胃壁厚度.结果50例被检者胃的MPR重建图像均能比较准确地对胃进行分区,测量并计算出各区胃壁厚度的正常值,分别为胃底区2.33±0.14mm,贲门区4.45±0.32mm,胃体区2.36±0.19mm,胃窦区3.58±0.25mm.结论S CT不但能比较准确地对胃进行分区而且能比较准确地观察胃壁的结构和测量各区胃壁的厚度.     

口服脂肪性造影剂后胃壁的CT观察

对１０２例口服１５％花生油乳剂行上腹部ＣＴ扫描的正常人胃壁的厚度及形态进行观察。对胃壁厚度及贲门壁厚度进行测量，经数据处理得出：正常人胃壁厚度在０．２～１．０ｃｍ范围之内，贲门部壁略厚，在０．２～１．１ｃｍ范围，形态光滑规整，贲门部形态大部分呈折角状，少部分呈三角形。     

CT在胃原发非霍奇金淋巴瘤与胃低分化腺癌鉴别诊断中的应用价值

目的：探讨CT在胃原发非霍奇金淋巴瘤与胃癌的鉴别诊断中的应用价值。资料与方法：经手术病理诊断且有CT扫描的胃原发非霍奇金淋巴瘤19例，胃低分化腺癌48例，结合病理诊断对比分析二者胃壁病变厚度、密度、范围、轮廓、与周围脏器的关系及腹腔腹膜后淋巴结肿大的情况。结果：胃淋巴瘤壁厚度0．4－6．5cm，平均2．07cm；胃癌胃壁厚度0．5－4．0cm，平均1．74cm（P＝0．2932)。胃淋巴瘤淋巴结受侵10例（52．63％），CT显示淋巴结肿大6例（31．57％），真阳性3例（15．8％），其中腹膜后淋巴结肿大1例（5．26％）；胃癌淋巴结转移38例（90．48％），CT显示淋巴结肿大20例（47．6％），真阳性19例（39．6％），其中伴腹膜后淋巴结肿大4例（9．52％）。胃淋巴瘤侵犯胃壁近似全周4例（22．2％），≥胃周径50％4例（22．2％），胃癌侵犯近拟全周7例（14．6％），≥胃周径50％6例（12．5％）；胃淋巴瘤外侵5例（26．32％），CT阳性3例（15．8％），胃癌外侵42例（87．5％），CT阳性31例（64．58％）。结论：CT扫描可以显示胃壁病变的厚度、密度、范围、与周围组织的关系以及腹腔腹膜后淋巴结肿大的情况。胃癌与胃淋巴瘤在密度、厚度上均无显著差异，当病变外侵和／或有腹腔淋巴结肿大时，胃癌可能性较淋巴瘤大；而当病变厚度和侵犯周径较大时，淋巴瘤可能性较胃癌大。是否有腹膜后淋巴结肿大不能提示病变性质，应参考其他阳性征象进行诊断。     

胃肠道淋巴瘤的影像学表现及特征

目的 探讨胃肠道淋巴瘤的X线、CT表现及特征.资料与方法回顾性分析经病理证实的41例胃肠道淋巴瘤患者的X线、CT资料,其中原发性36例,继发性5例.胃22例,肠道19例.归纳总结其影像表现及特征.结果41例中除5例病理诊断恶性淋巴瘤后未继续分型,余36例均为非霍奇金淋巴瘤,其中B细胞来源33例(91.7%),T细胞来源3例(8.3%).胃淋巴瘤的X线表现及特征有:孤立充盈缺损区内有增粗隆起的胃黏膜,并与正常胃黏膜移行相连;充盈缺损区内有结节状隆起的"鹅卵石征";龛影周围环堤的内外缘光整;胃壁广泛浸润,胃腔不狭窄或狭窄不明显;胃内跳跃病灶,病灶之间是正常胃结构;病变区胃壁柔软或有一定舒缩变化;胃淋巴瘤的CT表现及特征有:弥漫或局限性胃壁明显增厚,厚度1.1～5.8 cm,平均2.5 cm,增厚的内缘呈波浪样或分叶状,外缘清楚,周围脂肪间隙存在.肿块密度均匀,增强扫描呈轻中度均匀强化,并发现"肿瘤覆盖黏膜征".肠道淋巴瘤的影像表现及特征有:肠壁厚度2～6 cm,平均3.4 cm.病灶长度7～10 cm或广泛难以测量.增厚的肠壁内缘高低不平,可有不同程度狭窄,但梗阻不明显,增强扫描呈轻中度强化,特征性表现是肠壁呈动脉瘤样扩张.结论胃肠道淋巴瘤有较明显的X线、CT表现及特征,正确认识和掌握这些征象有助于对胃肠道淋巴瘤的诊断.     

MRI在胃癌术后复发诊断中的应用价值

目的:探讨MRI在胃癌术后复发诊断中的价值及临床意义.方法:选择2组胃癌术后患者,胃癌术后复发组33例,未复发对照组10例,均经胃镜活检、病理检查证实.2组病例均应用1.5 T MRI行TSE DRIVE/T2WI、T1-FFE T1WI等序列及动态增强扫描检查,测量残胃壁及吻合口胃壁厚度,观察吻合口胃壁MRI常规序列及动态增强信号变化.结果:未复发对照组残胃壁厚度(4.5±0.3)mm,吻合口胃壁厚度(6.3±1.4)mm;术后复发组残胃吻合口胃壁增厚＞8 mm 30例,吻合口邻近胃壁厚度＞5 mm 19例,吻合口软组织肿块并邻近胃壁增厚11例,肝脾胰腺等周围脏器转移5例,肝胃之间、腹腔、腹膜后淋巴结转移9例.病灶在动脉期不均匀强化9例,静脉期及平衡期病灶呈渐进性、延迟强化30例.结论:MRI能够较好地显示残胃壁及吻合口胃壁的厚度,准确判断肿瘤浸润深度及与周围组织毗邻关系、是否有淋巴结和腹腔内脏器转移等,可指导临床选择手术方案或综合治疗,对提高胃癌术后生存率具有重要的临床意义.     

进展期胃癌声像征象分析

通过２５０例进展期胃癌声像征象分析及２例离体标本实验并与病理对照，提出：（１）胃壁第１层强回声带是粘液层和表面上皮与胃显像剂的界面反射，第２层弱回声带是粘膜固有层及粘膜肌层，故胃癌观察重点应在第２层；（２）胃癌侧向侵犯以肌层最快，声像特征为肌层延伸征；（３）进展期胃癌的征象为：①粘液层中断征；②粘膜增厚及斜坡征；③胃壁层次破坏；④肿块突入腔内及胃腔狭窄；⑤火山口征；⑥胃壁增厚、僵硬、蠕动消失；⑦周围淋巴结及脏器转移。     

低场强MR成像在胃癌诊断中的应用研究

目的：探讨低场强ＭＲ成像技术在胃癌诊断中的作用。材料与方法：５０例正常成人服用不同量的水和造影剂（Ｇｄ－ＤＴＰＡ）溶液、空气,注射或不注射低张药物后,进行多方位、多系列ＭＲ增强前后扫描以资对照。３０例进展期胃癌患者,空腹４￣８小时,检查前１０分钟肌注６５４－２ ２０ｍｇ,检查前即刻喝水６００￣１０００ｍｌ,行多方位、多系列增强前后扫描。１８例手术患者,术前进行ＴＮＭ分期和可切除性评估。结果：ＭＲＩ     

Gastric cancer screening in selected population of Moscow region: retrospective evaluation

The aim of the study was to evaluate the efficacy of photofluorographic gastric cancer screening in selected population of Moscow Region (Russia) during a 15-year period. Thirty-five thousand patients were examined annually with photofluorography (tight filling and double contrast) of the stomach. Gastroscopy with multiple biopsies was performed in suspicious or inconclusive cases. Dynamic CT scan with air distention of the stomach was made before the operation for precise determination of tumor size as well as in some inconclusive cases. The final diagnosis was made by histologic examination of resected stomach. A total of 4286 patients dropped out of the study. In 25,392 patients no pathology was found. Gastric cancer was diagnosed in 680 (1.94 %) of patients. In the study 170 (25 %) “early” gastric cancers and 510 (75 %) advanced gastric cancers were found. Among 170 early gastric cancers 120 (70 %) were type-IIb (flat carcinoma) lesions in which endoscopy had low positive predictive value due to nonspecific picture and negative biopsy. On the contrary, dynamic CT scan with air distention of the stomach revealed local thickening of stomach wall in 118 of 120 (98.3 %) of the tumors and correctly determined their sizes in 106 of 120 (89.9 %). Gastric cancer screening by means of photofluorography in selected groups of patients is efficient and cost-effective. In doubtful cases with negative biopsies and nonspecific endoscopic image, dynamic CT scan with air distention of the stomach can be a method of choice. Received: 9 June 1998; Accepted: 30 June 1998     

Potential role of Calogen as an oral contrast medium in the evaluation of the gastric wall at MRI

Evaluation of gastric wall pathology using cross-sectional imaging has proved difficult, particularly in the imaging of early, localized disease. The properties of Calogen as a negative oral contrast agent for the evaluation of the upper gastro-intestinal tract and retroperitoneum in CT has been well described. We assess the suitability of this agent as an oral contrast medium for use in MRI examination of the gastric wall, finding the mean scores for Calogen and water with regard to gastric distension to be 8.46 and 5.49, respectively (P<0.01). Concerning obliteration of mucosal detail, the respective scores are 8.48 and 3.84 (P<0.01). Calogen is also statistically superior to water with regard to prevention of peristalsis and homogeneity (mean scores 8.15 vs. 5.74 and 8.69 vs. 6.30, respectively). Oral Calogen, therefore, is superior to water as an oral contrast agent for MRI examination of the gastric wall. Its ingestion allows identification of the gastric wall with fat intensity material on both sides, further aiding characterisation of subtle mural anomalies.     

Current role of CT in imaging of the stomach.

Recent advances in computed tomographic (CT) technology and three-dimensional (3D) imaging software have sparked renewed interest in using CT to evaluate gastric disease. Multidetector row CT scanners allow thinner collimation, which improves the visualization of subtle tumors as well as the quality of the 3D data sets. When water is used as an oral contrast agent, subtle disease is easier to visualize, especially when a rapid contrast material bolus is intravenously administered. Adenocarcinoma is the most common gastric malignancy and typically appears as focal or segmental wall thickening or a discrete mass. Gastric lymphoma can have a CT appearance similar to that of adenocarcinoma. Both gastric adenocarcinoma and lymphoma may be associated with adenopathy. Gastrointestinal stromal tumors (GISTs) tend to appear as well-defined masses that arise from the gastric wall and may be exophytic when large. GISTs are usually not associated with significant adenopathy. In addition to gastric malignancies, CT can also help detect inflammatory conditions of the stomach, including gastritis and peptic ulcer disease. CT angiography is especially helpful for depicting the gastric vasculature, which may be affected by a variety of disease conditions. Copyright RSNA, 2003.     

胃静脉曲张的CT表现（附15例报告）

本文对经手术或胃镜证实为胃静脉曲张的１５例患者的ＣＴ检查进行了回顾性分析，描述了胃静脉曲张的ＣＴ表现及其特点。胃静脉曲张特征性ＣＴ表现为注射造影剂后增厚的胃壁内可见条状或管状致密影，本组９例强化，７例显示特征性表现。ＣＴ检查还可以确定其原发疾病，脾血管和门静脉扩张程度，以及腹腔内侧支循环情况。     

胃淋巴瘤的CT诊断

目的：探讨胃淋巴瘤的ＣＴ表现及其诊断价值。材料和方法：回顾性分析１１例经手术或活检病理证实的胃非何杰金淋巴瘤的临床和ＣＴ检查资料。结果：１１例胃淋巴瘤中原发性６例、继发性３例,初诊时即属ＩＶ期者２例,病变的ＣＴ表现可分为三种类型：胃壁弥漫增厚型８例（７２．７％）,节段增厚型２例（１８．２％）,肿块型１例（９．１％）;平均厚度约３．１ｃｍ（１．６ｃｍ－６．０ｃｍ）。病灶边界清晰光整,增强后病灶呈轻度强化,病灶内表面胃粘膜呈明显线样强化,均无周围浸润。结论：胃淋巴瘤的ＣＴ表现有一定的特征,有助于诊断。     

Gastric ulcer bleeding: diagnosis by computed tomography

A case of CT demonstration of a bleeding gastric ulcer is presented, in a patient with confusing clinical manifestations. Abdominal CT was performed without oral contrast medium administration, and showed extravasation of intravenous contrast into a gastric lumen distended with material of mixed attenuation. It is postulated that if radiopaque oral contrast had been given, peptic ulcer bleeding would probably have been masked. CT demonstration of gastric ulcer bleeding, may be of value in cases of differential diagnostic dilemmas.     

CT appearances of mucosa-associated lymphoid tissue (MALT) lymphoma

Mucosa-associated lymphoid tissue (MALT) lymphoma is a low-grade lymphoma that differs from high-grade non-Hodgkin lymphoma both clinically and histologically. The CT appearances of MALT lymphoma are described. Of 40 patients referred with biopsy-proven MALT lymphoma, only seven had not had gastrectomy or chemotherapy prior to CT examination. The CT scans of these seven cases were analysed for the degree and extent of gastric wall thickening, enlargement of abdominal and extra-abdominal lymph nodes, and presence of extranodal disease. In all patients the stomach was distended with oral contrast medium and scans performed at narrow collimation, after intravenous administration of 20 mg hyoscine butylbromide. In six patients focal thickening of the gastric wall was 1 cm or less. One patient had thickening of over 4 cm. There was no enlargement of abdominal or extra-abdominal lymph nodes or extension to adjacent organs. Thus on CT, at presentation, MALT lymphoma results in minimal gastric wall thickening, unlike high-grade non-Hodgkin lymphoma, which typically causes bulky gastric disease, nodal enlargement and extension into adjacent organs. CT is therefore of limited value in monitoring response to treatment. With disease greater than minimal thickening, transformation to a higher grade should be considered. Received: 22 April 1998; Accepted: 27 October 1998