多排螺旋CT冠状动脉成像技术

目的 探讨多排螺旋CT在冠状造影中的应用，对冠状动脉进行评价(钙化，狭窄及冠状动脉瘤)对内支架及搭桥患者进行术后随访评价。方法 GE light speed ultra扫描机对患者在肘前静脉用高压注射器注入对比剂后，采用回顾性心电门控及分段数据采集方式，对患者进行心脏成像扫描。结果 冠状动脉显示清晰，满足诊断需要。MSCT冠状动脉造影是一种无创性，能获得较好的心脏三维图像，对冠状动脉病的诊断有很大潜力，在这项技术中，注药速度、延时时间、扫描层厚、扫描速度是紧密相关的，恰当与否直接影响图像质量。     

输尿管结石应用64排容积CT尿路成像的诊断价值

目的探讨64排容积CT尿路成像在输尿管结石中的诊断价值。 方法分析200例输尿管结石的患者,其被临床或者手术判定为输尿管结石,所有入选的患者行64排容积CT尿路成像,并采用不同图像后处理:多平面重组法、曲面重组、最大密度投影、容积再现、表面成像。 结果在入选的200例患者中,结石最小的直径为1.5mm,结石位于输尿管上段的有70例,位于下段的有83例,位于中段的有35例,位于输尿管上中下段的有12例。同时还发现合并输尿管畸形的患者。其中,合并肾囊肿的有100例,输尿管囊肿的有5例,膀胱憩室的4例,合并肾结石的有30例,合并膀胱结石的有10例,合并输尿管及肾积脓的2例,肾盂及输尿管畸形的有20例。 结论64排容积CT对于输尿管结石的定位、大小、形态、数量及其周围情况的诊断具有重要的价值,同时可显示泌尿系统是否合并畸形及肾结石、膀胱结石。     

胆道镜与CT胆管成像联合诊治胆管结石的临床应用

目的 探讨胆道镜与CT胆管成像联合诊治胆结石的临床价值.方法 回顾性分析167例行胆道镜手术的胆管结石患者资料,根据术前检查方式分为2组:常规组行常规B超检查,CT组在常规B超榆查基础上加做腹部CT扫描胆管,三维成像.对2组患者诊断的灵敏度、特异度、定位准确性、胆道镜结石取净率及术后并发症等进行统计分析.结果 CT组行CT胆管成像后结石发现率更高,定位更准确,以胆总管段最明显(P＜0.05),结石取净率高于常规组(P＜0.05).2组术后并发症发生率差异无统计学意义(P＞0.05).结论 胆道镜联合CT三维胆管成像对胆管结石的诊治具有重要的应用价值.     

多排螺旋CT泌尿系增强扫描技术及临床诊断中的价值

目的：探讨螺旋CT泌尿系增强的延时方法及重建对临床诊断的价值。以补充常规检查如超声、静脉尿路造影(IVU)、MRU的不足。方法：对临床泌尿系37例患者行螺旋CT普通扫描、增强扫描、增强延时扫描及三维重建的后处理。扫描分别选三种层厚6．5mm、3．2mm、1．3mm。结果：对尿路梗阻病人均能显示梗阻部位和梗阻程度其诊断率100％达到临床影像诊断效果。对肾盂、肾盏、输尿管、膀胱显示优于IVU和MRU。螺旋CT对泌尿系增强扫描层厚过大所重建图象不连续不能达到有效诊断效果。扫描层厚过薄其重建数据过多而影响重建速度及工作效率，患者不能常时间屏气而使图象产生呼吸动等假像。结论：多排螺旋CT以其扫描速度快及重建功能强大为各种增强扫描成为现实。笔者就肾脏、输尿管、膀胱进行增强及延时扫描的参数方法对3D、MPR、4D重建等进行了探讨。泌尿系完整的检查往往需要多个常规影像检查组合才能完成诊断。即如此有很大一部分病例诊断应较困难。螺旋CT对泌尿系增强扫描后，三维重建成像在泌尿系充盈高密度对比荆下分辨率明显提高。     

多层螺旋CT阴性法胆道成像的临床应用

目的：分析多层螺旋CT（MSCT）阴性法胆管成像在胆道梗阻病变诊断中的应用价值。方法：收集手术病理证实的各种胆道梗阻疾病患者共35例,分别就MSCT阴性法胆管成像对胆道病变的定位、定性诊断价值进行评价。结果：MSCT阴性法胆管成像的胆道病变定位准确率为100%,肿瘤病变诊断准确率为94.3%,对胆道结石的诊断准确率为82.9%。结论：MSCT阴性法胆管成像对胆道病变的诊断具有较高的临床应用价值。     

多序列MRI和MSCT诊断胆道结石对照研究

目的 对比探讨多序列磁共振成像(MRI)及多层螺旋CT (MSCT)诊断胆道系统结石的价值.方法 抽取2011年7月～2012年7月共58例胆道结石病例,均行MSCT平扫和多序列MRI检查,MRI检查序列包括:轴位T2 WI、轴位T2WI压脂、轴位T1WI、冠状位T2WI、厚层块MRCP和薄层MRCP.2种检查时间间隔不超过2天,所有病例均经手术和病理证实.按结石所在部位分成肝内胆管结石、上段胆总管结石、下段胆总管结石及胆囊结石进行统计.将MSCT和多序列MRI诊断结果进行对比,应用配对四格表行x2检验统计分析.结果 共102个部位存在结石,其中胆囊结石30个部位,上段胆总管结石9个部位,下段胆总管结石36个部位,肝内胆管结石27个部位.多序列MRI诊断100个部位存在结石,MSCT诊断66个部位存在结石,多序列MRI诊断正确率为98.03％(100/102),MSCT诊断正确率为64.7％(66/102),二者差异有统计学意义(x2=40.0,P＜0.01).结论 多序列MRI诊断胆道系统结石明显高于MSCT,为外科手术提供可靠的诊断依据.     

多排螺旋CT重建技术对输尿管结石的诊断价值

目的 分析CT重建对输尿管结石的诊断价值.方法 取院内输尿管结石60例为观察组,另取同期体检健康人员50例为对照组,均行CT重建技术检查,观察不同受试者检查结果.结果 观察组患者CT重建检查阳性率96.7％,对照组健康人员检查阳性率2.0％,2组间对比差异有统计学意义.本组60例患者中,输尿管结石检出58例,35例患者...     

膝关节半月板损伤的多排螺旋CT诊断

目的:探讨膝关节充气造影多排螺旋CT扫描对诊断膝关节半月板撕裂的诊断价值。方法:每个关节腔内注入20~50 ml空气后作CT扫描,将扫描所得数据输入工作站进行多平面图像重建(MPR)、最大密度投影(MIP)及容积再现技术(VRT),观察半月板撕裂,将CT诊断结果与术中所见比较。结果:30例中有26例为半月板撕裂,有21例经膝关节镜手术证实。结论:该方法可以较清晰地显示膝关节半月板撕裂,为外科治疗方案提供了重要的参考信息。     

MRI-FIESTA成像序列对胆道结石的诊断价值

目的：评价FIESTA成像序列对胆道系统结石的诊断价值。方法：30例CT诊断为肝内胆管结石患者,其中14例伴肝外胆管结石（肝总管6例,胆总管结石8例）,均行磁共振胰胆管水成像MRCP检查,同时对感兴趣区分别行薄层FRFFSE-T2WI脂肪抑制序列及FIESTA脂肪抑制序列扫描检查,比较其对结石的诊断符合率。所有病例后均经手术或ER-CP证实。结果：30例胆内胆管结石,MRCP＋FRFFSE组阳性19例,符合率63%;MRCP＋FIESTA组阳性26例,符合率87%,两者肝内结石符合率差异有统计学意义（P〈0.05）;而肝外胆管结石,MRCP＋FRFFSE组阳性15例,其中假阳性1例,MRCP＋FIESTA组阳性14例,两者符合率均近100%,肝外结石符合率无明显差异性。结论：FIESTA序列对胆道结石尤其是肝内结石有极高的临床诊断价值。     

Complementary role of helical CT cholangiography to MR cholangiography in the evaluation of biliary function and kinetics

To explore the potential role of computed tomographic cholangiography (CTC) in relation to magnetic resonance cholangiography (MRC) in cases in which knowledge of biliary kinetics and functional information are important for therapeutic decisions, 31 patients (14 men and 17 women) underwent MRC followed by CTC. We examined nine post-cholecystectomy cases with right upper quadrant abdominal pain, six cases with a previous biliary-enteric anastomosis and clinical evidence of cholangitis, eight biliary strictures with pain or symptoms of cholangitis, four cases with strong clinical evidence of sclerosing cholangitis, three cases with suspected post-laparoscopic cholecystectomy bile leakage, and one case with chronic pancreatitis and a common bile duct stent associated with cholangitis. In relation to MRC, CTC provided additional biliary functional information as follows: abnormal biliary drainage through the ampulla in 7/9 cholecystectomy cases, impaired drainage in 3/6 biliary-enteric anastomoses, and complete obstruction in 2/8 biliary strictures. CTC diagnosed early sclerosing cholangitis in 4/4 cases and confirmed suspected bile leakage in 1/3 post-laparoscopic cholecystectomy patients, and the patency of the biliary stent in the patient with chronic pancreatitis. Thus, CTC provides clinically important information about the function and kinetics of bile and complements findings obtained by MRC.     

经皮肝穿刺螺旋CT三维胆系造影对阻塞性胆管病变诊断价值的探讨

目的 :研究三维螺旋CT经皮肝穿刺胆系造影 (3D SCT PTC)对胆管梗阻性病变的临床应用价值。方法 :对 31例胆管扩张的患者 ,常规CT扫描图像选择穿刺胆管和针道。螺旋CT扫描从膈顶至胰腺钩突区 ,以MIP、SSD和曲面重建法合成三维胆管树影像。结果 :31例病人中 ,30例 (96 .8%)经皮肝穿刺胆系造影成功。 30例螺旋CT胆系造影均显示了胆管梗阻的部位、原因、程度及范围 ,2 7例 (90 %)胆管解剖和异常在MIP和曲面重建图像比轴位图像显示清楚。结论 :螺旋CT经皮肝穿刺胆系造影可避免常规X线PTC穿刺的盲目性 ,对比剂使用伊索显 ,用量少 ,并发症少 ,对梗阻的部位、原因、程度判断准确可靠 ,对明显胆管梗阻性病变的患者不失为一种有用的检查方法。     

Multidetector computed tomography (MDCT) in the diagnosis of pulmonary embolism: interobserver agreement among radiologists with varied levels of experience

Purpose: To assess the interobserver variability of radiologists with varied levels of experience in the interpretation of multidetector computed tomography (MDCT) pulmonary angiographies.

Material and Methods: Review of CT pulmonary angiographies performed on patients included in a diagnostic study evaluating a decision-based algorithm for diagnosing pulmonary embolism (PE). Five radiologists, three board-certified general radiologists and two radiology trainees with 2 years' experience, participated in the study.

Results: According to the consensus reading, PE was present in 91 (31%) and absent in 194 (67%) patients, while in five patients (1.7%) the interpretations were regarded as equivocal. The per-patient agreement on the diagnosis of PE achieved by each of the four readers compared to the consensus reading was very good (κ range 0.85-0.92), but peripheral emboli were missed in four to six patients by three of four observers. The agreement on the most proximal level of PE (per-proximal level) assessed by mean κ value was 0.83 (κ range 0.68-0.91) for the detection of proximal emboli, 0.61 for segmental emboli (κ range 0.40-0.80), and 0.38 for emboli in the subsegmental vessels (κ range 0.0-0.89).

Conclusion: The overall agreement on the diagnosis of PE by MDCT for general radiologists and radiology trainees is very good, and we therefore believe that the initial management of patients with suspected PE could be based on the preliminary assessment performed by on-call radiologists with 2 years of experience.     

Concordance of second-order portal venous and biliary tract anatomies on MDCT angiography and MDCT cholangiography

OBJECTIVE: We sought to investigate the concordance between second-order portal venous and biliary tract anatomies using MDCT angiography and MDCT cholangiography. MATERIALS AND METHODS: We retrospectively identified 56 living related potential liver donors who underwent both MDCT angiography and MDCT cholangiography. Two reviewers independently rated axial images and 3D reconstructions of MDCT angiograms and cholangiograms as diagnostic or nondiagnostic with respect to depiction of second-order portal venous and biliary tract anatomies. In images rated as diagnostic, second-order portal venous and biliary tract anatomies were categorized as conventional or variant. The concordance between portal venous and biliary tract anatomies was analyzed using McNemar exact chi-square test. RESULTS: All examinations were diagnostic. Second-order portal venous variants were seen in 10 (18%) and biliary branch variants were seen in 23 (41%) of the 56 patients. Patients with variant portal venous anatomy (6/10, 60%) were more likely to have variant biliary tract anatomy than patients with conventional portal venous anatomy (17/46, 37%; p < 0.01). The sensitivity of variant portal venous anatomy as a marker for variant biliary anatomy was 26% (6/23 patients). CONCLUSION: Concordance between second-order portal venous and biliary tract anatomies is statistically significant. However, in our series, a number of patients with conventional portal venous anatomy had variant biliary anatomy; therefore, the finding of conventional portal venous anatomy does not obviate preoperative biliary tract imaging in patients before liver donation.     

肝移植术后并发胆道狭窄的内镜下治疗

 目的:初步探讨内镜在肝移植术后胆道狭窄治疗中的临床应用价值.方法:通过十二指肠镜逆行胆管造影(endoscopic retrograde cholangiography,ERC)检查对肝移植术后胆道狭窄进行诊断,并根据检查结果做相应的内镜下介入治疗.结果:肝移植术后胆道狭窄38例,其中21例为吻合口狭窄(10例合并有胆瘘),17例为非吻合口胆道狭窄.针对不同情况进行鼻胆管引流术及塑料支架引流术等治疗,非吻合口胆道狭窄的患者内镜治疗较困难,需要多次进行内镜治疗.所有患者治疗后临床症状均明显改善,无严重并发症发生.结论:内镜对于肝移植术后胆道狭窄并发症的诊断与治疗安全而有效,胆道狭窄并发症的较快发现及时处理可使患者较快治愈.     

Navigator-triggered isotropic three-dimensional magnetic resonance cholangiopancreatography in the diagnosis of malignant biliary obstructions: comparison with direct cholangiography

PURPOSE: To compare the diagnostic accuracy of navigator-triggered isotropic three-dimensional (3D) MR cholangiopancreatography (MRCP) using parallel imaging for malignant biliary obstruction with direct cholangiography. MATERIALS AND METHODS: A total of 23 patients with malignant biliary obstruction underwent MRCP and endoscopic retrograde cholangiopancreatography (ERCP)/percutaneous transhepatic cholangiography (PTC). Two observers retrospectively evaluated 3D-MRCP and ERCP/PTC and recorded the level of obstruction and extent of tumor along with their confidence. The quality of images and morphologic appearance of stricture were also evaluated by two reviewers. The results of MRCP and ERCP/PTC were compared with surgical and histopathological data. RESULTS: 3D-MRCP was of diagnostic quality and free of artifacts in all patients, whereas ERCP/PTC examinations failed in three patients. For the evaluation of level of obstruction, there was no statistical significance between 3D-MRCP and ERCP/PTC. 3D-MRCP was superior to ERCP/PTC in the assessment of anatomical extent of hilar bile duct involvement, but did not show statistical significance. The accuracy of 3D-MRCP in determining tumoral extent of hilar cancer was higher than that of ERCP/PTC, but it was not statistically significant. The image quality of 3D-MRCP was superior to ERCP/PTC. There was good agreement between morphologic appearance at MRCP and those at ERCP/PTC. CONCLUSION: 3D-MRCP can accurately assess the level of obstruction and extent of tumor in patients with malignant biliary obstruction.     

Assessment of ureteral obstruction in patients with compromised renal function: Value of Curved Planar Reformations in MDCT

Objective

To evaluate the usefulness of MDCT using a curved planar reformation technique for the noninvasive assessment of the causes and level of ureteral obstruction in patients with compromised renal function.

Patients and methods

Between January 2012 and February 2013, 50 patients with clinical and sonographic manifestations of ureteral obstruction underwent non-contrast multidetector CT (MDCT) using a 16-slice machine. A total of 65 ureters were examined. Curved planar reformation images were performed to display the entire course of ureters in the same image. All patients had renal impairment with serum creatinine greater than 2.0 mg/dl. The gold standard for diagnosis of the cause of obstruction was ureteroscopy and/or open surgery. The sensitivity, specificity and overall accuracy of MDCT using curved planar reformation in the diagnosis of ureteral obstruction were calculated in comparison with the gold standard.

Results

A total of 65 ureters were examined (35 unilateral, 15 bilateral). The most common cause of ureteric obstruction was ureteric stone representing 27/65 (41.5%), followed by ureteric stricture representing 23/65 (35.4%). The lower third was the most affected in our study, it was encountered in 38/65 ureters (58.46%). The total sensitivity, specificity and accuracy of CPR for the cause of the ureteric obstruction were 98.5%, 98.5% and 97.8%, respectively (P value >0.05). CPR also was more sensitive and accurate for the level of ureteral obstruction with a total sensitivity of 100% and accuracy of 100% (P value >0.001).

Conclusion

Curved planar reformation MDCT is a useful noninvasive technique which is accurate in diagnosing the cause and level of ureteral obstruction in patients with compromised renal functions and is helpful for planning the therapeutic management of such patients.     

Assessment of the optimal temporal window for intravenous CT cholangiography

The optimal temporal window of intravenous (IV) computed tomography (CT) cholangiography was prospectively determined. Fifteen volunteers (eight women, seven men; mean age, 38 years) underwent dynamic CT cholangiography. Two unenhanced images were acquired at the porta hepatis. Starting 5 min after initiation of IV contrast infusion (20 ml iodipamide meglumine 52%), 15 pairs of images at 5-min intervals were obtained. Attenuation of the extrahepatic bile duct (EBD) and the liver parenchyma was measured. Two readers graded visualization of the higher-order biliary branches. The first biliary opacification in the EBD occurred between 15 and 25 min (mean, 22.3 min ± 3.2) after initiation of the contrast agent. Biliary attenuation plateaued between the 35- and the 75-min time points. Maximum hepatic parenchymal enhancement was 18.5 HU ± 2.7. Twelve subjects demonstrated poor or non-visualization of higher-order biliary branches; three showed good or excellent visualization. Body weight and both biliary attenuation and visualization of the higher-order biliary branches correlated significantly (P<0.05). For peak enhancement of the biliary tree, CT cholangiography should be performed no earlier than 35 min after initiation of IV infusion. For a fixed contrast dose, superior visualization of the biliary system is achieved in subjects with lower body weight.     

Magnetic resonance cholangiography: comparison of two- and three-dimensional sequences for assessment of malignant biliary obstruction

The purpose was to retrospectively compare two-dimensional (2D) magnetic resonance cholangiography (MRC) including breath-hold single-shot rapid acquisition with relaxation enhancement (RARE) and multislice half-Fourier RARE versus navigator-triggered 3D-RARE MRC in the evaluation of biliary malignancy. MRC findings were evaluated in 31 patients with malignant biliary obstruction, including biliary malignancy, gallbladder carcinoma, and ampullary cancer. Two observers independently reviewed the images to assess the overall image quality, artifacts, ductal conspicuity, extent of disease, diagnostic confidence of tumor extent, and origin of tumor. The results were compared with surgical and histopathologic findings. Studies obtained with 3D-MRC were of significantly higher technical quality than those obtained with 2D-MRC. However, the accuracy between two sequences for classification of tumor showed no statistical significance. There was no significant difference between the Az values of 2D- and 3D-MRC for overall tumor extent in bilateral second order branch, intrapancreatic common bile duct (CBD) involvement (Az = 0.889, 0.881 for 2D and Az = 0.903, 0.864 for 3D). Nor was there a significant difference between two sequences in the assessment of the origin of tumor. Although 3D-MRC has superior image quality over 2D-MRC, 3D-MRC showed no statistically significant difference in accuracy compared with 2D-MRC for evaluating the extent of disease in malignant biliary obstructions.