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1.
The aim of this study was to determine the accuracy of contrast-enhanced biphasic spiral CT as a screening tool in the preoperative evaluation of orthotopic liver transplant (OLT) patients. Spiral-CT examinations were performed before liver transplantation in 53 patients. Scans were retrospectively reviewed and compared with pathologic findings in fresh-sectioned livers. When findings between spiral CT and pathology were discordant, formalized livers were reexamined with lesion-by lesion evaluation. Fresh pathologic evaluation revealed 23 liver lesions (16 HCC, 7 macro-regenerative nodules). Malignancy was identified in 13 of 53 patients (24.5%). Pre-transplantation spiral CT depicted 27 liver lesions (23 HCC, 4 macro-regenerative nodules). Malignancy was suspected in 14 patients (26.4%). In 10 of 53 (18.9%), spiral CT and pathologic evaluation were discordant. Subsequent retrospective pathologic evaluation showed malignancy in 4 additional patients. Spiral CT compared with the retrospective pathologic findings revealed 36 real-negative, 14 real-positive, 0 false-positive, and 3 false-negative patients with malignancy. Sensitivity and specificity of spiral CT in detection of malignancy was 82 and 100%, respectively. Contrast-enhanced biphasic spiral CT is an accurate technique in the evaluation of patients preceding OLT. Routine fresh-sectioned liver pathologic findings are not as sensitive as previously estimated.  相似文献   

2.
CT of small-bowel obstruction in children: sensitivity and specificity.   总被引:3,自引:0,他引:3  
OBJECTIVE.:The aim of this study was to determine the sensitivity, specificity, and accuracy of CT in the diagnosis of small-bowel obstruction in children. MATERIALS AND METHODS: The CT scans of 30 children with surgically proven small-bowel obstruction, 22 children with ileus, and 29 children who served as controls were retrospectively reviewed by two of four interpreters who were unaware of the children's final diagnoses. Causes of obstruction in the patients included 19 adhesions, six cases of volvulus, five intussusceptions, four strictures, and two cases each of internal hernia and abscess. Eight obstructions had multiple causes. The CT scans were evaluated for the presence of small-bowel obstruction using a scale with five degrees of confidence. In cases of discrepancy of more than one level of certainty, a third interpreter was consulted. Criteria for small-bowel obstruction included a discrepancy in caliber between the proximal dilated and the more distal small bowels or generalized small-bowel dilatation (>2.5 cm) in the presence of a collapsed colon. An interpreter's rating that an obstruction was either present or probable was considered a positive finding; a rating indicating that the interpreter was not sure whether an obstruction was present or believed that an obstruction was not probable or saw normal anatomic structures was considered a negative finding for small-bowel obstruction. The cause and level of obstruction also were recorded. RESULTS: There were 26 true-positive (87%) and four false-negative (13%) interpretations for small-bowel obstruction. Among the interpretations of scans of patients with ileus, 68% were true-negative and 32% were false-positive interpretations for small-bowel obstruction. Among the control group, there were no false-positive readings. Sensitivity of CT was 87%, specificity was 86%, and accuracy was 86%. In the scans of children 2 years and younger, CT had a sensitivity of 100% and specificity of 0%. Of the patients with surgically confirmed levels of obstruction, the correct level of obstruction was described by both interpreters in 12 (86%) of 14 scans. The causes of obstruction were correctly identified in 14 (47%) of 30 scans. CONCLUSION: CT is both sensitive and specific for use in diagnosing small-bowel obstruction in children, especially in children older than 2 years.  相似文献   

3.
目的 回顾性分析胃常见恶性肿瘤的CT表现,探讨MSCT鉴别胃常见恶性肿瘤的意义.资料与方法 经手术病理证实的49例恶性胃肿瘤患者术前常规行MSCT增强扫描.两位放射科医师采用盲法对CT图像进行分析,评价病灶浸润胃壁的程度,病变处胃壁厚度,病灶累及范围,周围淋巴结肿大以及病变强化程度.结果 49例中,29例(59.1%)为腺癌,8例(16.3%)为淋巴瘤,12例(24.5%)为恶性间质瘤.腺癌主要表现为局限胃壁增厚或弥漫性浸润伴黏膜强化.淋巴瘤表现为局限于黏膜和黏膜下层的多区域侵犯,伴胃壁明显增厚和周围肿大淋巴结.恶性间质瘤的特征为突出于胃壁外的巨大肿块.结论 根据胃壁受累程度及侵犯区域,MSCT有助于鉴别三种较常见的胃恶性肿瘤.  相似文献   

4.
Intracranial aneurysms: evaluation in 200 patients with spiral CT angiography   总被引:12,自引:0,他引:12  
The goal of this study was to assess the usefulness of spiral CT angiography (CTA) with three- dimensional reconstructions in defining intracranial aneurysms, particularly around the Circle of Willis. Two hundred consecutive patients with angiographic and/or surgical correlation were studied between 1993 and 1998, with CTA performed on a GE HiSpeed unit and Windows workstation. The following clinical situations were evaluated: conventional CT suspicion of an aneurysm; follow-up of treated aneurysm remnants or of untreated aneurysms; subarachnoid haemorrhage (SAH) and negative angiography; family or past aneurysm history; and for improved definition of aneurysm anatomy. Spiral CTA detected 140 of 144 aneurysms, and an overall sensitivity of 97 %, including 30 of 32 aneurysms 3 mm or less in size. In 38 patients with SAH and negative angiography, CTA found six of the seven aneurysms finally diagnosed. There was no significant artefact in 17 of 23 patients (74 %) with clips. The specificity of CTA was 86 % with 8 false-positive cases. Spiral CTA is very useful in demonstrating intracranial aneurysms. Received: 13 April 1999 Revised: 22 March 2000 Accepted: 3 May 2000  相似文献   

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Kim SH  Kim YJ  Lee JM  Choi KD  Chung YJ  Han JK  Lee JY  Lee MW  Han CJ  Choi JI  Shin KS  Choi BI 《Radiology》2007,242(3):759-768
PURPOSE: To evaluate the use of multidetector computed tomographic (CT) esophagography to grade esophageal varices and differentiate between varices at low risk and those at high risk for bleeding, with endoscopy as the reference standard. MATERIALS AND METHODS: This study was approved by the institutional review board; all subjects gave informed consent. Ninety patients with cirrhosis (65 men, 25 women; mean age, 54.8 years; range, 21-77 years) were prospectively enrolled and underwent endoscopy and CT esophagography. Esophageal varices were graded independently at endoscopy by two endoscopists. CT esophagograms were interpreted retrospectively with a four-point scale by two radiologists blinded to other findings. Interobserver agreement between each radiologist and endoscopist was determined; endoscopic and CT esophagographic grades of esophageal varices were correlated. Radiologist performance for differentiation between low- and high-risk varices for bleeding on the basis of morphology at endoscopy was evaluated with receiver operating characteristic analysis. Patients were interviewed to determine acceptance at both examinations. RESULTS: Thirty-seven of 90 patients had grade 0, 23 had grade 1, 18 had grade 2, and 12 had grade 3 esophageal varices. Thus, 60 patients were determined to be in a low-risk group and 30 in a high-risk group for variceal bleeding at endoscopy. There was almost perfect agreement in grading esophageal varices between endoscopists. There was close correlation (P < .001) and substantial agreement between endoscopic and CT esophagographic grades. Radiologist performance for differentiating between low- and high-risk varices was 0.931-0.958 (area under receiver operating characteristic curve). Patient interview results revealed that CT esophagography had better acceptance than did endoscopy (P < .001). CONCLUSION: Use of CT esophagography allows grading of esophageal varices and differentiation between low- and high-risk varices and shows better patient acceptance than does endoscopy.  相似文献   

7.
OBJECTIVE: The purpose of this study was to determine the prevalence and spectrum of colonic wall changes in patients with cirrhosis and to determine the association between these colonic wall changes and portal hypertension. MATERIALS AND METHODS: Abdominal CT examinations of 57 patients with cirrhosis were evaluated for colonic abnormalities including bowel wall thickening and pneumatosis. The degree and extent of colonic involvement, other CT features of cirrhosis including ascites and portal hypertension, and clinical symptoms were recorded. A correlation was made with available colonoscopy, exploratory laparotomy, and pathologic results. RESULTS: Colonic wall abnormalities were seen in 37% (21/57) of the patients with cirrhosis, 25% (14/57) of whom had isolated or predominantly right-sided colonic changes. Abnormal bowel wall thickening (ranging from 6 mm to 3 cm in thickness) was present in 35% of the patients. Pneumatosis was found in 4% of the patients. Of the 18 liver transplant recipients who had CT examinations before and after liver transplantation, colonic changes were seen in 44% preoperatively but in only 6% postoperatively. Isolated right-sided colonic changes and diffuse colonic changes were associated with varices in 93% and 100% of the patients, respectively; with ascites in 93% and 100%, respectively; and with splenomegaly in 83% and 86%, respectively. Specific or focal bowel symptoms were present in only 29% of the patients with colonic changes, whether the changes were diffuse or isolated to the right side. CONCLUSION: Thirty-five percent of the patients with severe cirrhosis who underwent CT were shown to have colonic wall thickening; two thirds of these patients had thickening limited predominantly to the right colon. We postulated that predominantly right-sided colonic wall thickening may be related to changes in blood flow and hydrostatic pressures caused by portal hypertension. Many patients with isolated or predominately right-sided colonic wall thickening did not have specific or focal bowel symptoms, and in most patients, the colonic wall thickening resolved after successful liver transplantation, requiring no further testing. On the other hand, we found that pneumatosis or severe diffuse colonic wall thickening may indicate a more serious colonic problem such as ischemia or infection with Clostridium difficile and should prompt further investigation.  相似文献   

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PURPOSE: To determine the frequency and patterns of gastrointestinal wall thickening at contrast material-enhanced computed tomography (CT) in patients with cirrhosis. MATERIALS AND METHODS: Three radiologists retrospectively assessed the contrast-enhanced abdominal CT scans of 77 patients with cirrhosis and 100 patients without cirrhosis for gastrointestinal wall thickening from the stomach through the descending colon. The frequencies of wall thickening were determined in the cirrhosis and in the control groups and were compared by using the Fisher exact test. The segmental distribution, symmetry, and enhancement pattern were evaluated in all patients with cirrhosis and gastrointestinal wall thickening. RESULTS: Gastrointestinal wall thickening was seen in 49 (64%) patients with cirrhosis and in seven (7%) control subjects (P <.005). The jejunum and ascending colon were the most common sites of gastrointestinal wall thickening; each was involved in 32 (42%; 95% CI: 30%, 53%) patients. The scans of 30 (61%; 95% CI: 47%, 75%) patients with gastrointestinal wall thickening showed multisegmental distribution. Gastrointestinal wall thickening was concentric and homogeneous in all patients with cirrhosis. CONCLUSION: Gastrointestinal wall thickening is common on contrast-enhanced abdominal CT scans in patients with cirrhosis. It frequently involves multiple segments. The jejunum and ascending colon are the most common sites of involvement.  相似文献   

10.

Purpose

This study evaluated the feasibility and safety of percutaneous endovascular aneurysm repair (P-EVAR) in an “unselected” population of patients using Prostar XL closure device, comparing our results with the literature data reported for open EVAR (O-EVAR) and P-EVAR in selected populations.

Materials and methods

We prospectively enrolled 200 patients with abdominal aortic aneurysms to be treated with the P-EVAR procedure, without any selection criteria. Four hundred percutaneous femoral accesses using the Prostar XL closure device were performed. The early follow-up protocol consisted of a Doppler ultrasound (US) examination. Later evaluations were performed with US and computed tomography.

Results

Technical success was achieved in all percutaneous accesses (100 %). Ten early complications related to access site were recorded (10/400; 2.5 %): four pseudoaneurysms and six cases of lower limb ischaemia. Five of ten complications occurred in patients presenting calcification of the common femoral arteries, whereas 4/10 were in patients with “complex” groin anatomy. Eight of ten complications occurred at the access site of the main body of the prosthesis using a sheath size >20 Fr.

Conclusions

Percutaneous endovascular aneurysm repair in “unselected” patients is safe and efficient, with a very low risk of access-related complications, comparable to P-EVAR in selected populations and to the best O-EVAR series.  相似文献   

11.
Objective: This prospective study was carried out to assess the usefulness of high-resolution CT (HRCT) of the chest in immunocompromised renal transplant patients with suspected pulmonary infections.Material and Methods: Twenty-one consecutive renal transplant patients with clinically suspected pulmonary infections underwent chest radiography, HRCT and other tests including bronchoalveolar lavage (BAL). HRCT was performed using a high spatial frequency algorithm with 2-mm-thick sections at 10-mm intervals from apices to domes of the diaphragm. The findings on chest radiography and HRCT were interpreted by two thoracic radiologists and the usefulness of HRCT was evaluated. The images were interpreted independently by two radiologists, who were blinded to the findings of other imaging modalities and the final diagnosis. Any differences regarding the imaging findings were resolved through consensus.Results: Final diagnosis was obtained in 17 patients, and no cause for symptomatology was established in 4 patients. The spectrum of infections included pulmonary tuberculosis (TB) in 11 patients, cytomegalovirus pneumonia (CMV) in 2 patients, cryptococcal and streptococcal pneumonia, pulmonary aspergillosis and esophageal candidiasis in 1 patient each. Compared to chest radiography, HRCT revealed additional findings in 11 patients. HRCT findings were suggestive of underlying infection in 11 patients. The final diagnosis coincided with HRCT diagnosis in all but 1 patient. HRCT findings were non-specific in 3 patients and normal in 7. The findings were concordant in 19 cases. The results were not in agreement in only 2 cases.Conclusion: HRCT can provide useful information and suggest the diagnosis in a significant proportion of renal transplant patients with pulmonary infection.  相似文献   

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The purpose of this study was to evaluate the clinical feasibility of coronary artery imaging during routine preoperative 64-slice MDCT scans of the chest. Ninety-nine consecutive patients in sinus rhythm underwent a biphasic multidetector-row spiral CT examination of the chest without the administration of beta-blockers, including an ECG-gated acquisition over the cardiac cavities, followed by a non-gated examination of the upper third of the thorax. Data were reconstructed to evaluate coronary arteries and to obtain presurgical staging of the underlying disease. The percentage of assessable segments ranged from 65.4% (972/1,485) when considering all coronary artery segments to 88% (613/693) for the proximal and mid segments, reaching 98% (387/396) for proximal coronary artery segments. The 387 interpretable proximal segments included 97 (97%) LM, 99 (100%) LAD, 96 (97%) LCX and 95 (96%) RCA with a mean attenuation of 280.70±52.93 HU. The mean percentage of assessable segments was significantly higher in patients with a heart rate ≤80 bpm (n=48) than in patients with a heart rate greater than 80 bpm (n=35) (80±11% vs. 72±13%; P=0.0008). Diagnostic image quality was achieved in all patients for preoperative staging of the underlying disorder. The mean estimated effective dose was 12.06±3.25 mSv for ECG-gated scans and 13.88±3.49 mSv for complete chest examinations. Proximal and mid-coronary artery segments can be adequately evaluated during presurgical CT examinations of the chest obtained with 64-slice MDCT without the administration of β-blockers.  相似文献   

14.
PURPOSE: To determine the accuracy of helical computed tomography (CT) without the oral, intravenous, or rectal administration of contrast material in confirming suspected acute appendicitis. MATERIALS AND METHODS: Three hundred consecutive patients referred from the departments of surgery and emergency medicine were examined for suspected acute appendicitis by using thin-section nonenhanced helical CT. All transverse CT scans were obtained in a single breath hold from the upper abdomen (T12 vertebra) to the pubic symphysis with 5-mm collimation and a pitch of 1.6. All scans were obtained without oral, intravenous, or rectal contrast material. Criteria for diagnosis of acute appendicitis included an enlarged appendix (> 6 mm) and periappendiceal inflammation. CT diagnoses were recorded prospectively. Final diagnoses were established with the results of surgical or clinical follow-up or both. RESULTS: There were 110 true-positive diagnoses, 181 true-negative diagnoses (63 of which were an alternative diagnosis correctly established prospectively), five false-negative diagnoses, and four false-positive diagnoses, which yielded a sensitivity of 96%, a specificity of 99%, and an accuracy of 97%. CONCLUSION: Nonenhanced helical CT is a highly accurate technique for diagnosing or excluding acute appendicitis. Developing experience with the technique and understanding the subtleties of interpretation can further improve diagnostic accuracy.  相似文献   

15.
OBJECTIVE: We investigated whether CT signs can be used to predict hepatofugal flow in the main portal vein in patients with cirrhosis. MATERIALS AND METHODS: We retrospectively identified 36 patients with cirrhosis, 18 with hepatopetal and 18 with hepatofugal flow in the main portal vein, who underwent contemporaneous abdominal sonography and CT. Two independent observers evaluated the following features on the randomized CT studies: diameter of the portal, splenic, and superior mesenteric veins; spleen size; and the presence of ascites, varices, or arterial phase portal venous enhancement. These data were correlated with the flow direction seen on sonography. RESULTS: A small main portal vein was the only sign significantly (p 相似文献   

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PURPOSE: This paper aims to provide the tools for a complete anatomical evaluation of the coronary tree using 64-slice computed tomography (CT) and evaluate the prevalence of anatomical variants and anomalies in a population of 202 consecutive patients. MATERIALS AND METHODS: Two hundred and two patients with suspected coronary artery disease underwent 64-slice CT with a standard protocol. Two observers working in consensus evaluated and collected the data regarding anatomical variants and anomalies of the coronary vessels. RESULTS: In the 202 consecutive patients, the prevalence of anatomical variants was: left dominant circulation (7%), absent left main (5%), presence of intermediate branch (17%), aortic origin of conus branch (13%) and circumflex origin of sinus node branch (15%). Coronary anomalies (origin and course, intrinsic and termination) showed an overall prevalence of 25%. CONCLUSIONS: CT is the ideal method for the three-dimensional evaluation of the coronary tree. Anatomical variants and anomalies of the coronary arteries are quite common and should be known and recognised promptly by the operators.  相似文献   

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目的探讨肝硬化门静脉高压肝内外门-体循环交通的发生率及CT表现特点。方法回顾性分析80例肝硬化门脉高压患者的肝内外门-体交通的螺旋CT三期扫描表现。结果肝外型门-体循环交通见于79例(98.75%),其中,食管下段黏膜下及食管周围静脉曲张48例(60%),奇静脉和半奇静脉扩张28例(35%),小网膜静脉曲张46例(57.5%),副脐静脉肝外型再通20例(25%),脾肾静脉和胃肾静脉分流10例(12.5%),腹膜后椎旁静脉曲张14例(17.5%);肝内型门-体循环交通6例(7.5%),其中,5例为门静脉左支与副脐静脉交通型(6.25%),1例为门静脉右后支与下腔静脉交通型(1.13%)。结论螺旋CT三期扫描对肝硬化门静脉高压侧支循环的显示有独特的价值,不仅能显示侧支循环的部位、范围和曲张的程度,而且可以追踪血流异常途径。认识侧支循环的CT表现特点,有助于肝内外疾病的鉴别诊断。  相似文献   

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