MRI在肠梗阻病因诊断中的应用价值

目的 评价MRI在肠梗阻病因诊断中的应用价值. 资料与方法 应用MRI对临床拟诊为肠梗阻的39例患者进行检查,分析梗阻病因,并与手术或随访结果 对照. 结果 39例中有36例经手术证实,其中肿瘤所致梗阻25例,粪石、胆石梗阻4例,肠粘连4例,乙状结肠扭转3例.MRI术前定性诊断准确35例,1例小肠肿瘤误诊为炎症.梗阻部位在小肠者11例,在结肠者25例,MRI定位与手术一致.3例未手术者MRI诊断为粘连性肠梗阻,经保守治疗后缓解.MRI定性与定位诊断符合率分别为97%和100%. 结论 MRI可以较为准确地诊断肠梗阻病因及其梗阻部位,为临床制订治疗方案提供重要信息.     

CT在急性肠梗阻中的诊断价值

目的：探讨CT在急性肠梗阻中的诊断价值。材料与方法：回顾性分析59例经手术证实的急性肠梗阻病人的CT资料。结果：CT对急性肠梗阻病因诊断符合率为86％(43／50)，其中对肿瘤引起的肠梗阻有很高的准确性。CT对结肠病变梗阻部位的诊断较准确，对小肠病变梗阻部位的诊断欠准确。绞窄性肠梗阻的CT表现有特征性，CT的诊断对其治疗有指导意义。结论：CT在急性肠梗阻诊断中有重要价值。     

多层螺旋CT对老年肠梗阻诊断的价值

目的:探讨多层螺旋CT(MSCT)对老年肠梗阻的诊断价值.方法:对36例老年肠梗阻患者MSCT表现进行分析,其中30例行手术治疗,6例保守治疗.结果:MSCT准确显示肠梗阻的病例为100%.30例手术治疗患者中,28例手术结果与MSCT表现相符,包括肠道肿瘤15例,粘连性肠梗阻6例,腹外疝2例,胆石性肠梗阻2例,炎性作用引起的肠梗阻3例.结论:MSCT对老年肠梗阻的程度、梗阻部位及梗阻原因的诊断有重大意义,可作为肠梗阻的首选检查方法.     

多排螺旋CT对肠梗阻诊断的临床价值

目的探讨多排螺旋CT对肠梗阻诊断的临床价值。方法回顾性分析41例经临床保守治疗或手术证实的肠梗阻的螺旋CT影像资料,并将其诊断结果与手术、病理结果进行对照分析。结果多排螺旋CT诊断肠梗阻的准确性100%,对肠梗阻部位判断的准确性及病因判断有着独特的优势。其中肠肿瘤15例,粘连性肠梗阻21例（包括阑尾炎脓肿形成1例,肠憩室炎1例）,闭孔疝1例,腹股沟疝2例,肠系膜血管栓塞1例,后腹膜恶性纤维组织细胞瘤侵犯肠壁1例。结论多排螺旋CT在显示肠梗阻的存在与否、确定肠梗阻部位以及梗阻原因判断方面具有很高的临床价值。     

高场MRCP在梗阻性黄疸中的诊断价值

目的探讨MRCP对梗阻性黄疸定位和定性诊断的价值。方法对2010年4月～2011年7月来我院就诊的78例梗阻性黄疸患者进行MRCP及CT检查,并与临床手术病理结果对照,分别统计出MRCP、CT的定位及定性诊断准确率。结果 MRCP对梗阻定位诊断准确率、梗阻定性诊断准确率分别为89.74%、85.90%;CT对梗阻的定位、定性诊断率分别为67.95%、67.95%。结论 MRCP作为无创性检查技术,对梗阻性黄疸的定位与定性诊断准确率均高于CT,可作为胆系梗阻性病变诊断的首选检查。     

螺旋CT及重建技术对肿瘤性肠梗阻的诊断

目的评价螺旋CT及重建技术对肿瘤性肠梗阻的诊断价值。方法对25例经手术证实肿瘤性肠梗阻的CT表现及MPR、STS-MIP重建进行分析,并与手术病理进行对照研究。结果CT对肿瘤性肠梗阻的定位诊断和定性诊断正确率分别为100%及95%,MPR、STS-MIP可以分析供血动脉及引流静脉。结论螺旋CT及MPR、STS-MIP重建对肿瘤性肠梗阻的定性、定位诊断具有重要的临床价值。     

多层螺旋 CT 诊断肠梗阻的临床应用

目的：探讨多层螺旋CT（MSCT）在肠梗阻的诊断及其临床上的应用价值。方法回顾性分析并总结2012-2013年期间55例肠梗阻患者的CT表现。结果55例肠梗阻患者中,MSCT正确报告52例梗阻部位,准确率为94%;梗阻原因有50例与临床诊断结果完全相同,其符合率为91%,其中有17例粘连性梗阻,11例肠道肿瘤,4例肠扭转,3例肠系膜血管栓塞,3例肠套叠,3例粪石性梗阻,1例结石性梗阻,3例腹股沟疝,2例动力性肠梗阻,1例肠外肿瘤压迫,2例小肠内疝。结论 MSCT能快速准确地显示肠梗阻的部位及病因,并能清晰显示肠管周围情况,对临床治疗方案及预后评估有重要价值。     

螺旋CT在小肠梗阻诊断中的价值

目的:探讨螺旋CT在小肠梗阻诊断中的价值。方法:对64例小肠梗阻患者肌注低张剂、口服对比剂后行螺旋CT平扫和增强扫描,并与手术病理结果对照。结果:机械性小肠梗阻59例(其中肠肿瘤17例,炎性病变7例,腹外疝8例,腹内疝5例,肠粘连8例,腹茧症5例,胆石3例,肠套叠3例,肠扭转2例,粪块1例),CT诊断正确55例,诊断符合率93%。麻痹性肠梗阻5例,CT诊断正确3例,诊断符合率为60%。8例绞窄性肠梗阻,7例CT诊断正确,诊断符合率88%。结论:CT判断小肠梗阻的有无以及明确梗阻的部位、原因、程度和肠管缺血具有较高的准确性,是诊断小肠梗阻的可靠方法。     

经鼻型肠梗阻导管在小肠梗阻诊疗中的应用效果分析

目的：探讨经鼻型肠梗阻导管小肠减压与高选择性小肠造影在肠梗阻诊断及治疗中的应用价值。 方法：选取我院2012年2月—2014年10月收治的36例小肠梗阻患者,均在胃镜辅助下先行经鼻型肠梗阻导管置入减压,减压后通过肠梗阻导管进行高选择性小肠造影,动态多角度观察肠管的形态、运动及梗阻局部情况,对小肠梗阻的部位、范围、性质做出影像学诊断,并结合手术及病理结果和治疗效果进行分析。 结果：36例患者全部置管、造影成功。14例经非手术治疗治愈,22例经手术治疗治愈。本组病例术前影像诊断与临床最终诊断符合率为94.4%（34/36）。术前15例影像诊断粘连性肠梗阻,经非手术治疗痊愈13例,2例非手术治疗无效中转手术,非手术治疗梗阻解除率为86.6%（13/15）。8例影像诊断肿瘤性肠梗阻均行手术治疗,7例符合诊断,1例误诊为肠结核。5例影像诊断小肠内疝性肠梗阻均行手术治疗,4例符合诊断,1例误诊为肠粘连。4例影像诊断小肠结石性肠梗阻,其中3例手术治疗,1例经非手术治疗痊愈。4例影像诊断肠套叠性肠梗阻行手术治疗均符合诊断。 结论：经鼻型肠梗阻导管小肠减压能够迅速减轻肠梗阻症状,减少急诊手术,部分患者可经非手术治疗治愈。需要中转手术者,也可对其梗阻部位、程度及梗阻病因等进行初步判明,使手术更具针对性。经鼻型肠梗阻导管造影对小肠梗阻的定性定位诊断有较高的临床应用价值。     

螺旋CT对诊断肝外胆管梗阻的临床价值研究

目的 分析肝外胆管梗阻的螺旋CT表现,结合其他影像检查结果、临床资料及手术病理,评价螺旋CT对诊断肝外胆管梗阻的临床价值.方法 回顾分析46例肝外胆管梗阻的螺旋CT表现,其中26例平扫后进行了CT增强扫描,部分病例进行了MRCP、ERCP、PTC检查,对肝外胆管梗阻的定位和定性结果与手术病理结果进行对照.结果 经术后病理证实,良性病变为20例,恶性病变为26例,螺旋CT定位的准确率为96%,定性的准确率为87%.结论 螺旋CT对诊断肝外胆管梗阻的定位和定性诊断具有重要的临床价值,然而,肝外胆管梗阻的定性仍存在一定的困难,综合各种临床及影像学资料是提高确诊率的有效手段.     

Capability of abdominal 320-detector row CT for small vasculature assessment compared with that of 64-detector row CT

Objective

To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol.

Materials and methods

Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to have lung cancer underwent ADCT using step-and-shoot scan protocol. The other 30 suspected to have renal cell carcinoma underwent 64-MDCT using helical scan protocol. Two experienced radiologists independently assessed inferior epigastric, hepatic subsegmental (in the segment 8), mesenteric marginal (Griffith point) and inferior phrenic arteries by using 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the Mann-Whitney U-test was used to compare the scores for each of the arteries.

Results

Overall interobserver agreements for both systems were almost perfect (κ > 0.80). Visualization scores for inferior epigastric and mesenteric arteries were significantly higher for ADCT than for 64-detector row CT (p < 0.05). No significant difference was found for hepatic subsegmental and inferior phrenic arteries.

Conclusion

Small abdominal vasculature assessment by ADCT with step-and-shoot scan protocol is potentially equal to or better than that by 64-detector row CT with helical scan protocol.     

Aortoiliac and lower extremity arteries assessed with 16-detector row CT angiography: prospective comparison with digital subtraction angiography

PURPOSE: To prospectively compare the accuracy of 16-detector row computed tomographic (CT) angiography with conventional digital subtraction angiography (DSA) as the reference standard in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial disease. MATERIALS AND METHODS: This study was approved by the institutional review board, and informed consent was obtained. A total of 39 consecutive patients (27 men [mean age, 66 years] and 12 women [mean age, 64 years]) with peripheral arterial disease underwent both conventional DSA and 16-detector row CT angiography. For data analysis, the arterial vascular system was divided into 35 segments. A total of 1365 arterial segments were analyzed for arterial stenosis by two independent blinded readers using a four-point grading system (grade 1, <10% luminal narrowing; grade 2, 10%-49% luminal narrowing; grade 3, 50%-99% luminal narrowing; grade 4, occlusion). Interobserver agreements were calculated by using kappa statistics. A third independent blinded reader assessed possible reasons for disagreements between 16-detector row CT angiographic findings and conventional DSA findings. Effective radiation dose was calculated for both imaging modalities. RESULTS: Sixteen-detector row CT angiographic and conventional DSA findings were diagnostic in all vascular segments. Compared with conventional DSA, the sensitivity and specificity of 16-detector row CT angiography with regard to detection of hemodynamically significant stenosis in all 35 arterial segments were 96% and 97%, respectively, for both readers. Readers 1 and 2 overestimated arterial stenosis in 42 (3%) and 34 (2%) arterial segments, respectively, and underestimated arterial stenosis in 13 (1%) and 10 (1%) arterial segments, respectively. Interobserver agreement was excellent (kappa = 0.84-1.00). Presence of anteroposteriorly located luminal narrowing and extensive vascular wall calcification were considered main reasons for disagreements between imaging modalities. Effective radiation dose was lower for 16-detector row CT angiography (1.6-3.9 mSv) than for conventional DSA (6.4-16.0 mSv). CONCLUSION: Sixteen-detector row CT angiography is an accurate and reliable noninvasive alternative to conventional DSA in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial disease.     

320排容积CT冠状动脉血管成像在心律失常患者的应用

目的 评价320排CT容积扫描在心律失常(房颤和室性早搏)患者冠状动脉CT血管成像(CTCA)的可行性及其图像质量.方法 31例持续房颤和8例室性早搏患者.经320排CTCA检查.由2名有经验的放射科医师对CT图像质量(4级评分)进行评价,分析图像质量与患者的辐射剂量.2名评价者之间的一致性采用Kappa检验.结果 31例持续房颤和8例室性早搏患者中可评估的冠状动脉血管510段,其中496段(97.2％)达到诊断要求.患者的平均辐射剂量为(12.7±4.8)mSv.2名评价者对冠状动脉评分的一致性较好(Kappa=0.72).结论 房颤和室性早搏患者的CTCA检查具有可行性,心律失常患者可以不作为检查的禁忌证,但仍须进一步降低辐射剂量.     

多层螺旋CT三期扫描在胰腺癌诊断和分期中的价值

目的 评价多层螺旋CT三期扫描在胰腺癌诊断和分期中的价值。方法 对临床拟诊的胰腺癌患28例行动脉期，胰腺期，肝脏期三期扫描，延迟时间分别为20s,38s和75s。与病理结果对照，分析其诊断及可切除性评价的正确性。结果 28例CT诊断的胰腺癌中，26例正确诊断，诊断正确率为93%，2例因淋巴结转移不可切除的肿瘤，术前CT诊断为可以切除，其余24例均正确分期。结论 多层螺旋CT三期扫描以提供极好的影像质量在胰腺癌诊断和可是切除性评价方面具有重要价值。     

Blunt abdominal trauma: performance of CT without oral contrast material

PURPOSE: To retrospectively evaluate multi-detector row computed tomography (CT) without oral contrast material for depiction of bowel and mesenteric injuries that require surgical repair in patients with blunt abdominal trauma. MATERIALS AND METHODS: The investigational review board approved the study. Informed consent was waived. CT reports for October 2001 to September 2003 were reviewed and 1082 patients were identified who had undergone abdominopelvic CT with a multi-detector row scanner and without oral contrast material. Findings were divided into four categories: negative, solid organ injury with or without hemoperitoneum, free fluid only, and suspected bowel or mesenteric injury. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated by comparing CT findings with laparotomy reports and hospital course. RESULTS: CT findings were no intraabdominal injury (n = 932), solid organ injury only (n = 102), free fluid only (n = 34), and suspected bowel or mesenteric injury (n = 14). CT findings in patients suspected of having bowel or mesenteric injury were pneumoperitoneum with other secondary findings (n = 4), mesenteric hematoma and bowel wall abnormality (n = 2), mesenteric hematoma only (n = 4), and bowel wall thickening only (n = 4). In 11 patients, bowel or mesenteric injury was proved surgically. Thus, the study included 1066 true-negative, nine true-positive, two false-negative, and five false-positive results. Based on these data, sensitivity was 82% (95% confidence interval [CI]: 52%, 95%), specificity was 99% (95% CI: 98%, 99%), positive predictive value was 64% (95% CI: 39%, 83%), and negative predictive value was 99% (95% CI: 98%, 99%) for depiction of bowel and mesenteric injuries. CONCLUSION: Multi-detector row CT without oral contrast material is adequate for depiction of bowel and mesenteric injuries that require surgical repair. Results are comparable with previously reported data for single-detector row helical CT with oral contrast material.     

Small-bowel diseases: prospective evaluation of multi-detector row helical CT enteroclysis in 107 consecutive patients

PURPOSE: To prospectively evaluate multi-detector row helical computed tomographic (CT) enteroclysis for the depiction of small-bowel diseases. MATERIALS AND METHODS: The study group included 107 patients who were suspected of having small-bowel tumor (n = 8), active inflammatory small-bowel disease (n = 18), unexplained gastrointestinal bleeding (n = 36), refractory celiac sprue (n = 14), and low-grade small-bowel obstruction (n = 31). A nasoenteric tube was positioned into the duodenojejunal junction by using fluoroscopic guidance and water was infused with a pressure-controlled pump. After intravenous administration of 120 mL of iodinated contrast material, multi-detector row helical CT enteroclysis images were obtained with 4 x 2.5 mm collimation (four detector rows and 2.5-mm section thickness). Multi-detector row helical CT enteroclysis findings were analyzed by two readers working in consensus. Findings were compared with the results of endoscopy, enteroscopy, videocapsule endoscopy, histopathologic analysis, or clinical follow-up. RESULTS: Multi-detector row helical CT enteroclysis was well tolerated in 106 patients; one patient complained of abdominal pain after the examination. Multi-detector row helical CT enteroclysis allowed the diagnosis of small-bowel masses (n = 21), active Crohn disease (n = 9), small-bowel tuberculosis (n = 2), small-bowel lymphoma complicating celiac disease (n = 4), and confirmed low-grade small-bowel obstruction (n = 12). Multi-detector row helical CT enteroclysis demonstrated normal findings in 60 patients. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of multi-detector row helical CT enteroclysis were 100%, 95%, 97%, 94%, and 100%, respectively. CONCLUSION: Multi-detector row helical CT enteroclysis allows depiction of small-bowel diseases in patients suspected of having small-bowel conditions.     

Aortoiliac gadolinium-enhanced CT angiography: improved results with a 16-detector row scanner compared with a four-detector row scanner

PURPOSE: To assess the level of vascular enhancement of gadolinium-enhanced aortoiliac computed tomographic (CT) angiography with a 16-detector row CT scanner and to compare it with the results of previous similar studies that used four-detector row CT units. MATERIALS AND METHODS: Eleven gadolinium-enhanced CT angiograms were obtained in 10 consecutive patients with contraindication to iodinated contrast medium with use of a 16-detector row CT scanner. In the region of interest, attenuation measurements (in HU) were obtained from the proximal abdominal aorta to the common femoral arteries during unenhanced, gadolinium-enhanced, and delayed acquisitions. The results were compared to those in the 15 consecutive patients who most recently had similar examinations performed on a four-detector row CT unit. Phantom studies with diluted gadolinium were conducted to compare attenuation between CT units. RESULTS: On four-detector row CT, throughout the scan length, mean enhancement values were 53.8 HU +/- 5.3 and 15.0 HU +/- 2.6 for gadolinium-enhanced and delayed series, respectively. For the 16-detector row CT unit, they were 76.1 HU +/- 3.4 and 21.3 HU +/- 1.3, respectively. As a result of a shorter scan time and a more optimal start time, the 16-detector row CT unit provided significantly greater and more consistent enhancement throughout the scan length compared with the four-detector row CT unit (P =.0106). Similar structures had significantly greater enhancement when 120 kV was applied instead of 140 kV (P =.0495) CONCLUSION: The 16-detector row CT scanner improved gadolinium-enhanced CT angiography results compared with the four-detector row CT unit.     

心率对64层螺旋CT冠状动脉成像图像质量的影响

目的:评价心率对64层螺旋CT冠状动脉成像图像质量的影响.方法:采用GE Light speed 64层螺旋VCT,以心脏扫描模式对心脏动态体模进行扫描.心脏动态体模由3个部分组成:动力部分、解剖结构模拟部分和控制部分.心脏动态体模的心率设置为40、45、50、55、60、65、70、75、80、85、90、95、100、105、110和115次/min,心律齐.以球管转速0.35 s对不同心率下的心脏动态体模进行冠状动脉成像扫描.所有扫描数据在R-R间期90%时相分别进行单扇区和多扇区重建.重建数据传至工作站后处理成像.后处理方法采用VR、MPR重组模式.分别对重建图像进行评分.结果:①心率与图像质量呈负相关(P＜0.01);随着心率的增加,图像质量评分呈下降趋势;②在同一条件下多扇区重建算法较单扇区重建算法提高了图像质量评分.结论:采用心脏动态体模评价心率对64层螺旋CT冠状动脉成像图像质量的影响,对临床研究和应用有着重要价值.     

Assessment of coronary stents using 40-detector row CT: comparison with 16-detector row CT in vitro

OBJECTIVE: To evaluate the performance of 40-detector row computed tomography (CT) in the assessment of coronary stents in comparison with 16-detector row CT. METHODS: A total of 6 vascular models (3 models without stenosis and 3 with stenosis) using 3 types of stent (Bx-Velocity, Express2, and Driver) with an approximately 3.5-mm inner diameter filled with contrast material (450 Hounsfield units) were scanned with 2 computed tomographic scanners (collimation, 16 x 0.75 and 40 x 0.625 mm). We evaluated the in-stent stenosis visually for the 6 vascular models in 4 orientations (0, 30, 60, and 90 degrees) to the z-axis of the scanner. We evaluated attenuation values of the stent lumen of the 3 patent models in the 4 orientations. The average and standard deviation of the luminal attenuation values were assessed to evaluate the degree of blooming and streak artifacts. RESULTS: The visualization of the stent lumen of the vascular models at 90 degrees was improved using 40-detector row CT. For all the 3 stents, the average luminal attenuations values using 40-detector row CT were significantly lower than those using 16-detector row CT in all orientations. For all the 3 stents, the standard deviations of the luminal computed tomographic attenuation using 40-detector row CT were significantly smaller than those using 16-detector row CT in the 4 orientations to the z-axis except for Express 2 at 0 degrees. CONCLUSIONS: The visualization of coronary stents is improved by the use of 40-detector row CT with reduced blooming and streak artifacts.     

Multi-detector row CT angiography in the assessment of coronary in-stent restenosis: a systematic review

Purpose

The aim of this study was to perform a systematic review of the diagnostic accuracy of multi-detector row computed tomography angiography (MDCT) for detection of coronary in-stent restenosis in patients treated with coronary stenting when compared to invasive catheter angiography.

Materials and methods

A search of PUBMED and MEDLINE databases for English literature was performed. Only studies with at least 10 patients comparing 16- or more detector rows MDCT angiography with invasive catheter angiography in the detection of coronary in-stent restenosis (more than 50% stenosis) were included for analysis. Sensitivity and specificity estimates pooled across studies were tested using a fixed effects model.

Results

15 studies met selection criteria for inclusion in the analysis. There were eight studies performed with 16-detector row CT scanners, and five studies with 64-detector row scanners and one study with a 40-detector scanner. The remaining study was performed with a mixture of 16-and 64-detector row scanners. Prevalence of in-stent restenosis following coronary stenting was 18% (95% CI: 13, 24%). Pooled estimates of the sensitivity and specificity of overall MDCT angiography for the detection of coronary in-stent restenosis was 85% (95% CI: 78, 90%) and 97% (95% CI: 95, 98%), respectively. No significant difference was found between 16- and 64-detector row scanners regarding the sensitivity and specificity of MDCT for assessment of in-stent restenosis (p > 0.05).

Conclusion

The results showed that MDCT angiography (with 16 or more detector rows) has moderate sensitivity and high specificity for the detection of coronary in-stent restenosis when compared to invasive catheter angiography. A high specificity value of MDCT may be most valuable as a non-invasive technique of excluding coronary stent restenosis or occlusion. The main factors affecting visualization are stent diameters and stent materials.