CT evaluation of right colonic wall lesions

CT of the entire clean colon after a tap water enema with intravenous injection of contrast medium was performed in 20 patiens with a diagnosis of caecal and ascending colonic lesions at barium enema studies or colonoscopy. Histological proof was obtained by endoscopy or at surgery in all cases. Using this water technique we were able to detect the wall abnormalities and describe their CT features in relation to the histological findings. We found that asymmetric thickening of the bowel wall, an irregular and lobulated inner and outer contour and/or a focal soft tissue mass usually exceeding 2 cm from the luminal to serosal surface were very helpful findings for a malignant lesion but not the hallmark of malignancy. The CT appearance of the extraluminal part of the lesion was most helpful in differentiating between benign and malignant lesions.     

Intraventricular mass lesions

Determining the precise etiology of an intraventricular mass can be a difficult diagnostic problem. CT and angiographic findings were reviewed in a series of 73 patients who had intraventricular masses. The histologic diagnosis can be suggested preoperatively by an analysis of the frequency of lesions occurring at a given ventricular location, lesion density before and after administration of contrast material, age and sex of the patient, morphologic appearance of the mass, and presence or absence of hydrocephalus. Angiography is useful when meningioma, choroid plexus papilloma and carcinoma, or arteriovenous malformation are considered. The differential features of each diagnostic entity are discussed.     

Acute gastrointestinal hemorrhage: the changing role of barium examinations.

The emergency evaluation of a patient with acute life-threatening gastrointestinal hemorrhage requires the coordinated efforts of medical, surgical, and radiologic personnel. In most patients with an acute upper gastrointestinal hemorrhage, endoscopy represents the primary diagnostic procedure. Arteriography may follow, depending on the identification of the lesion at endoscopy or the need for therapy through the vascular catheter. Arteriography should precede endoscopy when bleeding is massive or the clinical situation suggests that therapy by a catheter must be instituted on a more urgent basis. When personnel are available to perform endoscopy and arteriography, the barium examination of the upper gastrointestinal tract is best postponed for a few days until the patient can be stabilized completely. In the patient with massive red rectal bleeding and a negative nasogastric aspirate, the arteriogram is clearly the procedure of choice for the emergency diagnostic evaluation. Bleeding diverticular and vascular ectatic lesions can be diagnosed only by arteriography and treatment can usually begin immediately by a catheter infusion of vasopressin. Colonoscopic and barium enema examinations of the acutely bleeding patient are not reliable. In addition, the presence of barium in the colon interferes with arteriography for a number of hours. The barium examination of the colon should be performed at some time during the hospitalization to exclude other possible bleeding lesions and to provide a better overall anatomic assessment of the colon. Both the retrograde and antegrade small bowel enemas are useful in detecting obscure small bowel bleeding lesions that occasionally present as a massive lower gastrointestinal hemorrhage.     

Cloacogenic carcinoma. Radiological appearance during double-contrast enema

Radiographic appearances at double contrast enema of 8 cases of anorectal cloacogenic carcinoma are described. In all cases tumor was radiologically identified as a neoplastic lesion, but the correct histologic diagnosis was not reached in any case. Radiological features of the cloacogenic carcinoma are: the evident submucosal mass, the poor mucosal involvement and the eccentricity of the lesion. However, the characteristics of the tumor are not peculiar and radiologic diagnosis of the nature of tumor can only be suspected.     

Comparison of radiologists' confidence in excluding significant colorectal neoplasia with multidetector-row CT colonography compared with double contrast barium enema

The aim of this study was to compare the confidence of experienced radiologists in excluding colonic neoplasia with CT colonography (CTC) compared with barium enema. 78 patients (median age 70 years, range 61-87 years, 44 women) underwent same day CTC and barium enema. Two radiologists experienced in reporting barium enema assessed whether the examination had excluded a polyp 6 mm or greater as "yes", "probably" or "no" for each of 6 colonic segments. Two different radiologists experienced in CTC independently performed the same assessment on the CT datasets. Responses were compared using a paired exact test. Formal barium enema and CT reports were compared with any endoscopic examination performed within 1 year. Studies reporting polyps 6 mm+ in patients not subsequently undergoing endoscopy were reviewed by two independent observers. Radiologists stated they had confidently excluded a significant lesion in 314 (71%) and 382 (86%) of 444 segments with barium enema and CTC, respectively (p<0.001). Confidence was significantly higher with CTC in the in the descending and ascending colon (p = 0.02 and p<0.001, respectively), and caecum (p<0.001). 22 patients underwent some form of endoscopy. Of five patients with proven colorectal neoplasia (including two with cancer), CTC and barium enema correctly identified five and three, respectively. In 56 patients not undergoing endoscopy, CTC reported 17 polyps 6 mm+, of which 16 were retrospectively classified as definite or probable. 11 could not be identified on the barium enema, even in retrospect. Confidence in excluding polyps 6 mm or larger is significantly greater with CT colonography particularly in the proximal colon.     

Importance of the dimensions and histologic nature of polyps of the colon in a comparison between double contrast enema and colonoscopy

In 244 patients the results obtained by double contrast barium enema and endoscopy in the detection of small colonic polyps were compared. The results were evaluated by subdividing the polyps according to size. In order to define the endoscopic false positives percentage, controversial cases were re-examined with a second double contrast barium enema. The authors put forward a few considerations on the suitability of diagnosing small colonic polyps on the basis of their histologic nature.     

Colon cancer at barium enema examination and colonoscopy: a study from the county of Hordaland, Norway

PURPOSE: To evaluate the efficacy of barium enema examination as routinely performed in the detection of colon cancer in the inhabitants of a well-defined and circumscribed geographic region. MATERIALS AND METHODS: The study comprised 571 patients with histopathologically verified colon cancer during 1990-1993 from the county of Hordaland. The barium enema examination results were reviewed retrospectively. RESULTS: The correct diagnosis was reached in 351 cases (sensitivity, 90.9%) in 386 tumor locations on the basis of the results of 381 barium enema examinations. Cancer or an important precancerous lesion was overlooked in 26 cases (6.7%), and the examination was not feasible in nine cases (2.3%). The correct diagnosis was reached in 172 cases (sensitivity, 80.0%) in patients with 215 tumor locations on the basis of the results of 213 colonoscopies. Cancer or an important precancerous lesion was overlooked in 13 cases (6.0%). The examination was technically not successful (i.e., the affected area was not reached with the scope) in 30 cases (13.9%). CONCLUSION: Barium enema examination is valuable in the diagnosis of colon cancer and compares favorably with colonoscopy. The main reason for missed radiologic diagnosis is failure to observe important lesions visible on the radiographs.     

多层螺旋CT成像技术在结肠肿瘤诊治中的应用

目的　提高多层螺旋CT对结肠肿瘤诊治中的认识。方法　通过对30例结肠肿瘤病人的MSCT轴位图像和重建的4-D、MIP及仿真内窥镜图像进行观察分析,分别对各病例进行诊断及术前评估,并与其相应的钡灌肠及纤维结肠镜结果进行对照性研究。结果　所有病人的诊断符合率为100%,明显优于其它检查方法,其仿真内窥镜结果与纤维结肠镜结果吻合。结论　多层螺旋CT在结肠肿瘤的诊治中,具有独特的优越性。     

结肠隆起性病变的X线诊断(附60例分析)

选择性的对130例血便、腹泻、腹疼患者进行了结肠双对比灌肠。发现73例结肠内存有隆起性病变。被证实的60例涉及有15种疾病。本文分析了隆起性病变的双对比造影表现征象,结合文献复习讨论了隆起病变的病理基础,发病情况及恶性潜能。从表现出的大小、单发、多发、形状特征的不同,联系临床对所遇疾病进行了诊断分类及鉴别诊断的探讨。提出以隆起性病变用作X线表现的命题,从而避免与各种息肉病的混淆。     

Diagnostic yield of barium enema examination after incomplete colonoscopy

PURPOSE: To determine the diagnostic yield of barium enema examination for neoplastic lesions larger than 1 cm in diameter in the nonvisualized portion of the colon after incomplete colonoscopy. MATERIALS AND METHODS: A review of computerized gastroenterology and radiology databases identified 355 patients who underwent incomplete colonoscopy; 158 (44.5%) underwent subsequent barium enema examination (125 double-contrast and 33 single-contrast barium enema examinations). The radiographic reports were reviewed and compared with the endoscopic reports by one author to identify neoplastic lesions larger than 1 cm in the nonvisualized colon after incomplete colonoscopy. Six such lesions were found. In all six cases, the images from the barium enema examinations were reviewed together by two authors to determine the size, location, and morphologic features (polypoid, ulcerated, or annular) of the lesions. Medical, endoscopic, and surgical records were subsequently reviewed by one author to determine whether these represented true- or false-positive radiographic findings. RESULTS: Barium enema examination depicted six possible lesions in the nonvisualized colon after incomplete colonoscopy; five were found to be true-positive radiographic findings, and one was found to be a false-positive finding. The five true-positive findings included two annular lesions (both adenocarcinomas) and three polypoid lesions (all tubulovillous adenomas, with high-grade dysplasia in one). Thus, neoplastic lesions larger than 1 cm were found on barium enema images in the nonvisualized colon in five (3.2%) of 158 patients after incomplete colonoscopy. CONCLUSION: Barium enema examination had a diagnostic yield of 3.2% for neoplastic lesions larger than 1 cm in the nonvisualized colon after incomplete colonoscopy.     

螺旋CT对结肠癌的诊断及术前分期价值

目的评价口服清水、2%泛影葡胺灌肠后螺旋CT扫描对结肠癌的诊断及术前分期价值。方法40例结肠癌患者检查前一日进流质饮食,检查当日晨常规清洁灌肠,口服清水、2%泛影葡胺灌肠后行CT扫描,结果与术后病理对照分析。结果直肠癌2例,乙状结肠癌7例,降结肠癌6例,横结肠癌5例,升结肠癌20例;根据Dukes’改良分期法,分为B期22例,C期12例,D期6例,与手术符合率为89.6%。结论螺旋CT扫描结合口服清水、2%泛影葡胺灌肠对结肠癌的诊断及术前分期有重要意义。     

MR characteristics of primary extramedullary plasmacytoma in the head and neck.

PURPOSETo define MR characteristics of primary extramedullary plasmacytoma in the head and neck using a variety of plain and contrast-enhanced MR protocols.METHODSSix patients with primary extramedullary plasmacytoma in the head and neck were examined clinically and with MR imaging at 1.5 T. The morphologic appearance and signal intensities of the lesions were analyzed and the results of the imaging findings were compared with histopathologic findings.RESULTSQualitative analysis showed that five lesions were oval and sharply demarcated without signs of infiltration; the other lesion filled the parapharyngeal space bilaterally. On t2-weighted sequences, the lesions had moderate signal intensity. On plain T1-weighted sequences, the tumors were isointense or slightly hyperintense with respect to surrounding muscles; after administration of contrast medium, four lesions notable enhancement, with distinct central inhomogeneity.CONCLUSIONAlthough morphologic features or evidence of contrast enhancement do not assure certain diagnosis of extramedullary plasmacytoma, these MR imaging characteristics should prompt the radiologist to include this rare lesion in the differential diagnosis.     

结肠镜与钡灌肠检查在直肠癌诊疗中比较

目的：比较钡灌肠和纤维结肠镜在直肠癌诊治中的作用。方法：本研究对北京肿瘤医院1996年4月-1999年12月住院的直肠癌手术病人进行回顾性分析，共收集资料全面同时进行纤维结肠镜和钡灌肠检查的病人51例进行分析，对比两种检查方式对于直肠肿瘤及合并结肠疾病的诊断。结果：在51例直肠癌中，钡灌肠检查时漏诊2例，对于纤维结肠镜检查发现的8例合并存在的结肠息肉全部漏诊。结论：在直肠癌的术前检查中纤维结肠镜检查应该作为常规的检查项目，而钡灌肠检查除非特殊情况下，一般不宜用这种方法检查同时合并的结肠病变。     

Characteristic appearances of colonic lipomas on barium enema: a guide to conservative management

The double contrast barium enema appearances of seven colonic lipomas are reviewed. These lesions have submucosal features: intact mucosa, sharp margination and obtuse angles between the lesion and the adjacent colonic wall, as well as features characteristic of lipomas: pliability and shape change, broad pedicles and spherical appearances en face. They can be differentiated from the more significant colonic adenomas and then CT scanned to establish a histological diagnosis. The need for colonoscopic or surgical excision of these predominantly asymptomatic lesions occurring in elderly patients can be considerably reduced.     

Conventional and indirect digital radiographic interpretation of oral unilocular radiolucent lesions

OBJECTIVES: To compare the diagnostic processes for the main unilocular radiolucent lesions of the mandible in the presence of the following variables: conventional and digital radiography, specialization of the examiner and type of lesion. METHODS: Twenty-four panoramic radiographs were selected from the archives of the AC Camargo Hospital (S?o Paulo, Brazil), aiming at comparing the diagnostic processes for similar unilocular radiolucent lesions of the mandible, with the following histopathological diagnosis: six ameloblastomas, six dentigerous cysts, six keratocysts and six traumatic bone cysts. The radiographs were scanned and processed using the Trophy 2000 software. Three specialists, each from four related areas (pathologists, stomatologists, radiologists and oral surgeons), randomly evaluated the radiographs before and after digitalization. RESULTS: The kappa statistic showed a high level of agreement between results obtained using the two radiographic techniques. This means that, in general, the examiners diagnosed the same cases correctly or incorrectly regardless of the method used. CONCLUSIONS: Based on generalized estimating equations, it was concluded that the probability of correct diagnosis does not depend on the kind of lesion, on the radiographic technique or on the specialization of the examiner. In view of the differing opinions of the specialists regarding the diagnostic validity of some software features available and of the results obtained in indirect digital technique, it may be reasonable to reconsider its use for diagnosis of bone pathology.     

Imaging of cecal tumors using computer tomography

Although contrast enema of the colon and endoscopy remain the preferential diagnostic methods in tumour of the caecum, computed tomography can accurately determine the extent of extraluminar tumour growth and hence help to arrive preoperatively at the appropriate therapeutic concept. Adenocarcinomas are morphologically distinctly different, due to focal thickenings of the colon wall, from the diffuse wall thickenings associated with malignant lymphomas, or from inflammatory conglomerate tumours. Computed tomography of the caecal region is a noninvasive examination method that can speed up diagnosis especially in elderly patients with elongated colon and stool incontinence.     

Large colonic neoplasms missed by endoscopy

Endoscopy is commonly accepted as the gold standard in the evaluation of neoplastic colonic disease. The procedure is used to confirm or exclude lesions detected on barium enemas, with the assumption that the endoscopist was successful in reaching the appropriate segment of the colon. We collected 18 cases, all with proved colonic neoplasm 2-8 cm in diameter that were detected by barium enema but overlooked on initial endoscopy. All of the lesions were relatively flat with little intraluminal protuberance. Histologic examination showed malignant foci in six of 11 tumors that were resected. In two of the other seven patients, unresected lesions progressed to advanced carcinomas. This experience suggests that a repeat barium enema is indicated when endoscopy fails to detect a colonic tumor suspected on barium enema examination.     

腹腔及腹膜后包虫病的B型超声及CT诊断

目的：探讨腹腔及腹膜后包虫病的B型超声及CT表现特征。材料和方法：回顾分析38例包虫病(29例手术病理证实,38例Casoni试验阳性)的B型超声及CT表现。结果：CT检查24例,表现为单发10例,多发14例；单囊型16例,多囊型8例。B型超声检查35例,表现为单发15例,多发20例；单囊型21例,多囊型14例。B型超声和CT对本病的确诊率分别为71．4%和100%。结论：B型超声和CT检查能准确地显示腹腔包虫囊肿的部位和形态特征,对该病的诊断和治疗有重要意义。     

Diagnostic imaging of gastrointestinal leiomyosarcoma. Experience with 12 cases

PURPOSE: Gastrointestinal (GI) leiomyosarcoma is an uncommon malignant cancer arising in the smooth muscle of the alimentary tract. It is known for its widely variable patterns and aspecific symptoms and signs preventing correct clinical assessment in the majority of cases. We will illustrate the key role of diagnostic imaging in the detection and staging of this lesion, describing the most suggestive imaging findings for the correct diagnosis. MATERIAL AND METHODS: January, 1990, to June, 1998, we examined 12 patients with GI leiomyosarcoma; they were 10 men and 2 women whose age ranged 42 to 85 years (mean: 63.7 years). Four lesions were found in the stomach, 3 in the jejunum and ileum, and 2 in the rectum. Due to the difficult clinical assessment of this type of lesion and to the development of emergency conditions, we could plan no diagnostic protocol in advance; thus, the most suitable diagnostic imaging approach was decided on the spot for studying the supposedly involved GI portions. Double contrast studies, US, CT and endoscopy were performed and each patient underwent at least two examinations. RESULTS: Barium contrast studies were performed in 9 patients: the lesion was detected in 7 cases and tumor site and extent were defined in 5, while the double contrast study of the colon allowed to exclude large bowel involvement in 2 ileal tumors. In all 9 cases US and US-guided endoscopy permitted better assessment of extra-luminal spread and involvement of adjacent organs. CT, which is essential to staging, provided useful information suggesting the lesion nature: a round, inhomogeneous mass in continuity with the intestinal wall, with irregular margins, peripheral enhancement after i.v. injection of contrast material and a central necrotic area. Histology confirmed CT diagnosis in 7/9 cases while an aspecific diagnosis of large retroperitoneal and abdominal lesion was made in 2 cases. CT did not allow to define the origin of 2 large exophytic lesions in the stomach and jejunum and missed peritoneal metastases in 3 cases. CONCLUSIONS: Although the aspecific and quite variable clinical patterns make it extremely difficult to plan a correct diagnostic protocol, in our experience all diagnostic imaging techniques played a fundamental role in identifying and staging alimentary tract leiomyosarcoma. Particularly, CT showed high sensitivity and specificity in characterizing and staging this lesion but exhibited rather poor sensitivity in recognizing peritoneal spread.     

大肠侧向发育型肿瘤(LST)的内镜诊治

目的 回顾性分析南方医院近2年内在肠镜检查中发现的46例共47个大肠侧向发育型肿瘤(LST)病变的检出及处理情况。方法记录所有LST病变的部位、大小、形态特征及内镜下大体分型．所有病例均行放大内镜观察病变表面的pil形态．46例LST患者中,42例共42个病变接受内镜下治疗,其中14例行注射法内镜下黏膜剥离切除术(EMR)切除病变．24例行注射法内镜下黏膜剥离分片切除术(EPMR)切除病变,1例行透明帽辅助EPMR切除病变,3例行单纯高频电热圈套切除术切除病变。结果 LST检出率：常规肠镜检查中LST病变检出率为0．8％。病变分布：47个LST病变中,直肠22个．乙状结肠10个．降结肠7个．横结肠4个,升结肠2个,盲肠2个。内镜下病变大体分型：颗粒均一型25个,结节混合型12个,平坦隆起型8个．似凹陷型2个。Pit形态：Ⅱ型pit2个,Ⅱ型 Ⅲ1型pit8个,Ⅲ1．型pit9个,Ⅳ型pit28个。病理形态：绒毛状腺瘤28例,均伴中度以上不典型增生．其中7例有局部癌变(6例m癌,1例sml癌),但根部无癌残留;增生性息肉2例;管状腺瘤11例,10例合并中度不典型增生．1例局部癌变(m癌);锯齿状腺瘤(Serrated腺瘤)6例。结论 大肠LST病变在我国有较高的检出率,其内镜形态具有一定特殊性。处理方法可采用内镜下黏膜切除术。