肝硬化CT分型与中医证型相关性研究

目的:探索肝硬化CT分型与中医证型之间的关系及其意义。方法:通过分析142例肝硬化患者CT表现和中医征象,对其进行CT分型和中医辨证分型,并分析两种类型之间的关系。结果:142例肝硬化根据CT征象分为3个类型,均匀型32例(22.54%),节段型21例(14.79%),结节型89例(62.68%)。中医辨证分为6个证型,肝郁脾虚证17例(11.97%),湿热蕴结证18例(12.68%),气滞血瘀证31例(21.83%),水湿内停证41例(28.87%),脾肾阳虚证21例(14.79%),肝肾阴虚证14例(占9.86%)。均匀型和节段型肝硬化病例中大多为肝郁脾虚证和湿热蕴结证,分别占62.49%和47.62%;其次为气滞血瘀证和水湿内停证,分别占28.13%和42.86%;脾肾阳虚证和肝肾阴虚证最少,分别占9.38%和9.52%。而结节型肝硬化病例中以肝郁脾虚证和湿热蕴结证最少,占5.62%;其次为脾肾阳虚证和肝肾阴虚证,占33.71%;气滞血瘀证和水湿内停证最多,占60.67%,与均匀型和节段型具有显著性差异(χ2值分别为49.40和32.06,P值均小于0.001)。结论:肝硬化的CT分型与中医证型之间存在密切的关联,2种分型均与肝硬化肝损害的严重程度相关。     

内镜下食管胃底静脉曲张治疗对肝硬化患者肝脏及脾脏弹性指数的影响

目的 探讨肝硬化患者肝脏及脾脏弹性指数在内镜下食管胃底静脉曲张治疗前后的变化.资料与方法 选取拟行内镜下食管胃底静脉曲张治疗的肝硬化患者85例,其中51例行内镜下食管胃底静脉曲张治疗(治疗组),34例行常规胃镜检查(对照组).治疗前后分别采用实时剪切波弹性成像测定肝脏及脾脏弹性指数并进行分析.结果 治疗组患者治疗后肝脏弹性指数由(22.13±7.98) kPa上升为(29.46±12.49) kPa,脾脏弹性指数由(39.66±9.80) kPa上升为(47.49±10.68) kPa,差异均有统计学意义(t=-6.322、-4.924,P＜0.01).对照组肝脏及脾脏弹性指数治疗前后差异无统计学意义(P＞0.05).结论 肝硬化患者肝脏及脾脏弹性指数经食管胃底静脉曲张治疗后显著上升,可敏感地反映门脉压力改变,具有一定的临床意义.     

CT测量脾脏指数预判肝硬化食管静脉曲张及出血的可能

目的探讨利用脾脏大小指数(sp len ic index,SI)来预测食管静脉曲张的程度及食管静脉破裂出血的可能性。方法肝硬化患者36例,均行内窥镜及CT检查。通过CT片测量脾脏大小计算SI,内窥镜观察食管静脉曲张的程度。结果(1)SI与食管静脉曲张程度之间呈显著正相关r=0.776P=0.001;(2)SI与肝硬化代偿及失代偿期之间有显著性差异(P=0.004);(3)SI与肝硬化有无出血之间亦有差异(P=0.029);(4)SI与肝硬化有无食管静脉曲张之间有差异(P=0.031);(5)SI与性别,年龄及肝硬化有无腹水之间无相关关系。当SI>940.42 cm3时,肝硬化患者有食管静脉曲张的可能性大。结论SI对预测高危食管静脉曲张有一定价值。SI值较大时提示有食管静脉曲张破裂出血的危险。     

脾脏淋巴瘤的CT诊断价值

目的:探讨脾脏淋巴瘤的CT特征性表现,提高影像学诊断水平.方法:回顾性分析了经病理学证实的19例脾脏淋巴瘤的CT形态学的表现和强化方式.结果:19例患者脾脏体积测量为415.32～4196.15cm3,平均(1615±709.7) cm3.脾脏肿大17例(17/19,89.5％).肿块型病灶直径＞3cm2例(2/19,10.5％);结节型病灶直径＜3cm单发性4例(4/19,21.1％),多发性11例(11/19,57.9％);弥漫型病灶直径＜5mm 2例(2/19,10.5％).CT平扫时病灶中心区CT值约为(40.43±9.44) HU;增强后动脉期病灶中心区CT值约为(51.46±13.42) HU,静脉期病灶中心区CT值约为(66.36±21.71) HU,CT平扫时病灶中心区与增强后的动、静脉期病灶密度差异有统计学意义(P＜0.001).结论:CT能很好地显示脾脏淋巴瘤的病灶形态学改变和CT强化特点,可明显提高脾脏淋巴瘤诊断的准确性.     

多层螺旋CT动态增强对孤立性肺结节血流模式的评价

目的探讨多层螺旋CT(MSCT)动态增强在孤立性肺结节血流模式定量评价中的作用及鉴别诊断中的价值.资料与方法 37例孤立性肺结节(直径≤4cm,24例恶性,6例良性,7例炎性)患者,行MSCT动态增强扫描(以4ml/s的流率注入对比剂90ml).记录孤立性肺结节增强前的CT值、强化值及灌注值,孤立性肺结节与大动脉强化值比.灌注值=时间-密度曲线最大斜率/大动脉强化值.结果恶性(37.98±17.97HU)与炎性(43.86±14.20HU)结节强化值明显高于良性(5.65±6.43HU)结节(P＜0.001;P＜0.001).恶性与炎性结节强化值无显著差异(P=0.647＞0.01).炎性结节与大动脉强化值比(20.78%±4.14%)明显高于良性(2.00%±2.26%)与恶性(14.63%±6.22%)结节(P＜0.001;P=0.021＜0.05).恶性结节与大动脉强化值比明显高于良性结节(P＜0.001).炎性(78.39±55.18ml/min/100g)结节灌注值明显高于良性(2.13±2.84ml/min/100g)与恶性(33.91±15.58ml/min/100g)结节(P＜0.001;P=0.001＜0.01).恶性结节灌注值明显高于良性结节(P＜0.001).炎性(39.36±9.57HU)与良性(37.73±8.39HU )结节增强前的CT值明显低于恶性(45.73±4.21HU)结节(P=0.04＜0.05;P=0.014＜0.05).炎性与良性结节增强前的CT值无显著差异(P=0.836＞0.01).结论 MSCT动态增强能提供孤立性肺结节血流模式的定量信息,有助于孤立性肺结节的鉴别诊断.     

孤立肺结节多层螺旋CT容积灌注成像的临床价值

目的 探讨多层螺旋CT容积灌注成像在孤立肺结节诊断中的价值.资料与方法 85例孤立肺结节(直径≤4cm,57例恶性,15活动性炎性,13例良性)患者,在增强(从肘静脉注入非离子型对比剂)前、后采用ToshibaAquilionMarconi16层螺旋CT(采用4×i模式,i代表扫描层厚)及GELightspeed64层螺旋CT(采用8×i或16×i模式,i代表扫描层厚)进行同层动态扫描.11～41s,每1s扫描1次;90s扫描1次.16层螺旋CT:病灶直径3～4cm时,扫描层厚8mm;2～3cm时,扫描层厚6mm;1.5～2cm时,扫描层厚4mm;1～1.5cm时,扫描层厚3mm;＜1cm时,扫描层厚2mm.64层螺旋CT:病灶直径3～4cm时,扫描层厚5mm;＜3cm时,扫描层厚2.5mm.记录孤立肺结节增强前后各时相的CT值.分别计算肺结节有效层面的强化值、灌注值、结节-主动脉强化值比、平均通过时间,有效层面参数的平均值作为肺结节的容积灌注成像定量参数.结果 恶性(36.52±11.07)HU与炎性(37.69±7.10)HU结节强化值明显高于良性(7.02±5.85)HU结节(P＜0.001;P＜0.001).恶性与炎性结节强化值无显著差异(P=0.686＞0.05).炎性结节与大动脉增强峰值比(17.49±3.78)%明显高于良性(2.78±2.23)%与恶性(14.73±4.28)%结节(P＜0.001;P=0.019＜0.05).恶性结节与大动脉增强峰值比明显高于良性结节(P＜0.001).炎性(47.83±31.29)mlmin-1100g-1结节灌注值明显高于良性(3.03±3.01)mlmin-1100g-1与恶性(31.15±9.66)mlmin-1100g-1结节(P＜0.001;P＜0.001).恶性结节灌注值明显高于良性结节(P＜0.001).炎性(33.00±8.87)HU与恶性(40.45±7.03)HU结节平扫的CT值明显低于良性(50.51±10.87)HU结节(P＜0.001;P＜0.001).炎性低于恶性结节平扫的CT值(P=0.002＜0.01).结论 多层螺旋CT容积灌注成像有助于结节鉴别诊断.     

CT及DSA在肝小静脉闭塞症鉴别诊断中的应用

目的探讨CT及DSA在肝小静脉闭塞症鉴别诊断中的应用价值。方法收集2012年~2016年我院12例肝小静脉闭塞症、12例布加综合征和12例肝炎后肝硬化病例的临床资料,对其CT及DSA影像检查结果进行对比研究。结果 1)侧支循环显示情况:肝小静脉闭塞症组较少,与另两组差异有统计学意义(P0.01);2)肝小静脉闭塞症可见肝脏弥漫性肿大(5例)、尾状叶增大(7例)、肝实质低密度斑片状区(3例)、肝实质弥漫性密度减低(8例),所有病例均可见中-大量腹水;布加综合征可见肝脏弥漫性肿大(3例)、尾状叶增大(9例),少数病例可见多发良性结节(2例)、腹水(4例);肝炎后肝硬化可见肝脏体积明显缩小(12例)、肝脏边缘波浪状(10例)、肝裂增宽(8例)、左叶增大(12例)、脾大(4例)、腹水(4例)等。肝小静脉闭塞症门脉期地图样强化,布加综合征特征的表现为扇样强化,而乙肝肝硬化则肝实质强化相对均匀。结论 CT及DSA在肝小静脉闭塞症的鉴别诊断中具有重要的应用价值。     

多层螺旋CT评价肝炎后肝硬化肝功能的价值

目的 评价16层螺旋CT对肝炎后肝硬化疾病的严重程度与肝功能Child分级相关性的价值.方法 对62例肝硬化患者行全腹16层螺旋CT扫描,用仪器自身携带体积测量软件测定全肝、左外叶、尾状叶及脾脏体积.肝硬化CT分级纳入参数有全肝体积、左外叶体积、尾状叶体积、脾脏体积、脾/肝比、腹水、侧枝循环、肝表面改变.将上述观察指标与Child-Pugh分级行相关分析.结果 肝左外叶体积(P=0.001)和腹水评分(P=0.001)与肝硬化严重程度(Child分级)呈明显相关性.结论 多层螺旋CT能准确评价肝硬化肝功能严重程度.肝左外叶体积越大,肝功能越好;腹水程度越重,肝功能就越差.     

肝尾状叶CT矢状面测量与肝硬化之间的关系探讨

目的 探讨正常人肝尾状叶大小变化的规律及其与肝硬化患者之间的关系.资料与方法 经临床资料、CT及B超证实的30例肝硬化患者和30例正常人肝脏分别行正中矢状面、斜矢状面、垂直斜矢状面CT重组,计算重组后各矢状面的有效层数及肝尾状叶长径及短径的值,比较正常人与肝硬化患者肝尾状叶的关系.结果 肝尾状叶正常组与肝硬化组各矢状面有效层数差异均有统计学意义(P值＜0.001);正常组与肝硬化组各有效层面上尾状叶长径与短径比较均有显著统计学差异,且以正中矢状面短径之间(P=0.001)和斜矢状面短径之间最可靠(P＜0.001),灵敏度分别为73.33%(22/30)、76.67%(23/30),特异度分别为73.33%(22/30)、80.00%(24/30).结论 对肝尾状叶正中矢状面、斜矢状面和垂直斜矢状面有效层数、长径与短径的测量能为临床诊断肝硬化提供有利证据.     

乙肝肝硬化背景小肝癌CT与MRI强化特征的比较研究

目的 比较乙肝肝硬化背景小肝癌(SHCC)CT与MRI的强化特征.方法 87例乙肝肝硬化SHCC患者共计91个病灶均行CT和MRI动态增强扫描,分别测量病灶平扫及增强各期CT值和MRI信号强度值,计算增强后CT与MRI各期相对强化率和病灶-肝脏对比率,绘制时间-密度/信号强度曲线并分型,观察记录病灶CT与MRI动脉期强化方式及假包膜的显示情况,分析比较乙肝肝硬化背景SHCC CT与MRI的强化特征.结果 MRI动脉期及平衡期SHCC相对强化率较CT高,差异有统计学意义(P＜0.05),CT与MRI门静脉期SHCC相对强化率差异无统计学意义(P＞0.05).MRI动脉期、门静脉期及平衡期SHCC病灶-肝脏对比率均较CT高,差异均有统计学意义(P＜0.05).CT与MRI SHCC时间-密度/信号强度曲线类型差异有统计学意义(P＜0.05),两两比较速升速降型及速升缓降型差异有统计学意义(P＜0.05),缓慢上升型及基本无强化型差异无统计学意义(P＞0.05).CT与MRI SHCC动脉期强化方式差异无统计学意义(P＞0.05).MRI动态增强SHCC假包膜显示率较CT高,差异有统计学意义(P＜0.05).结论 CT和MRI动态增强都能很好地反映SHCC相对肝实质的"陕进快出"的强化方式,MRI对显示SHCC动脉期快速强化的特征及假包膜较CT有优势,而CT更有利于观察SHCC强化"退出"的特点.     

Hypoxemia and liver cirrhosis (hepatopulmonary syndrome) in eight patients: comparison of the central and peripheral pulmonary vasculature

PURPOSE: To evaluate the pulmonary vasculature in patients with hepatopulmonary syndrome. MATERIALS AND METHODS: Conventional computed tomographic (CT) scans in eight patients with hepatopulmonary syndrome were retrospectively evaluated to compare the diameters of the pulmonary trunk, right and left main pulmonary arteries, and peripheral pulmonary vasculature in the right posterior basal segment with those in eight healthy subjects and in four patients with normoxemic cirrhosis. With thin-section CT, the ratio of segmental arterial diameter to adjacent bronchial diameter in the right lower lobe in four patients with hepatopulmonary syndrome was compared with that in four patients with normoxemic cirrhosis. RESULTS: In patients with hepatopulmonary syndrome, the peripheral pulmonary vasculature was significantly dilated compared with that in control subjects and in patients with normoxemic cirrhosis (P = .002); however, the central pulmonary arteries were not significantly dilated (P > .05). At thin-section CT, the ratio of segmental arterial diameter to adjacent bronchial diameter was significantly greater than that in patients with normoxemic cirrhosis (P < .05). CONCLUSION: In patients with hepatopulmonary syndrome, the peripheral pulmonary vasculature is significantly dilated. Dilatation of the peripheral pulmonary vasculature may be helpful in the diagnosis of hepatopulmonary syndrome.     

多层螺旋CT 灌注成像诊断肝硬化分级的临床价值分析

目的：探讨肝硬化患者的多层螺旋C T灌注成像特点及诊断价值。方法50例肝硬化患者和50例同期健康体检者纳入研究,对比两组的多层螺旋CT 灌注成像参数差异。结果研究组BF ,BV ,PVP ,THBF均显著低于对照组,而MTT ,HAP ,HPI显著高于对照组 P ＜0．05。不同程度肝硬化之间的 HAP ,PVP ,THBF ,HPI均有显著差异,P＜0．05。CT分级与Child‐Pugh分级正相关,相关系数0．927,P ＜0．05。结论多层螺旋CT灌注成像可为早期肝纤维化、肝硬化的诊断、评估及判断预后提供影像学基础,具有较高的临床价值。     

肝硬化Child-Pugh分级与LGV内径关系的MSCTA分析研究

目的探讨胃左静脉(LGV)和门静脉(PV)内径与肝硬化Child-Pugh分级间的关系。资料与方法应用16层螺旋CT对100例肝硬化患者和200名正常对照者行上腹部增强扫描,采用多平面重组(MPR)、最大密度投影(MIP)和容积重组(VR)对PV和LGV进行血管重建,测量LGV和PV主干的直径并进行统计学分析。结果总体肝硬化组LGV和PV管径与正常对照组比较明显增粗(P<0.05)。Child-A级和B级组PV最大内径较正常对照组和Child-C级组显著增粗(P<0.05)。Child-C级组和正常对照组、Child-A级和B级组PV最大内径比较差异无统计学意义(P>0.05)。正常对照组、肝硬化无腹腔积液组、肝硬化有腹腔积液组LGV内径逐渐增粗且差异具有统计学意义(P<0.05)。结论多层螺旋CT血管成像(MSCTA)可以清晰显示LGV和PV整体解剖结构,并能准确测量其内径,LGV和PV内径与肝硬化程度存在一定关系,但影响LGV和PV内径因素较多,不能单纯依靠管径大小评价肝硬化程度。     

Gastrointestinal wall thickening in patients with cirrhosis: frequency and patterns at contrast-enhanced CT

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.     

Dynamic CT of portal hypertensive gastropathy: significance of transient gastric perfusion defect sign

AIM: To evaluate the "transient gastric perfusion defect" sign as a way of diagnosing portal hypertensive gastropathy (PHG) on multidetector computed tomography (CT). MATERIALS AND METHODS: Ninety-two consecutive patients with cirrhosis underwent three-phase CT and endoscopy. Endoscopy was performed within 3 days of the CT examination. As controls, 92 patients without clinical evidence of chronic liver diseases who underwent CT and endoscopy were enrolled; the findings at endoscopy were used as a reference standard for patients with PHG. Two radiologists who were unaware of the results of the endoscopy retrospectively interpreted the CT images. PHG was diagnosed on dynamic CT if the transient gastric perfusion defect sign was present. The transient gastric perfusion defect was defined as the presence of transient, segmental or subsegmental hypo-attenuating mucosa in the fundus or body of the stomach on hepatic arterial imaging that returned to normal attenuation on portal venous or equilibrium-phase imaging. The frequency of the transient gastric perfusion defect sign was compared between these two groups using Fisher's exact test. The frequency, sensitivity, specificity, positive predictive values, and negative predictive values of the transient gastric perfusion defect sign were also compared between patients with PHG and without PHG in the cirrhosis group. RESULTS: Nine patients of 92 patients with cirrhosis were excluded because of previous procedure or motion artifact; the remaining 83 patients with cirrhosis were evaluated. In the cirrhosis group, 40 (48.1%) of 83 patients showed the transient gastric perfusion defect sign. In the control group, none of the 92 patients showed the transient gastric perfusion defect sign. In the cirrhotic group, the frequency of the transient gastric perfusion defect sign was significantly higher in the patients with PHG (75%, 36/48) than in patients without PHG (11.4%, 4/35). The sensitivity, specificity, positive predictive values, and negative predictive values of the sign for CT diagnosis of PHG in the cirrhosis group were 75, 88.6, 90, and 72.1% respectively. CONCLUSION: The transient gastric perfusion defect sign could be used as a relatively specific sign of PHG in patients with cirrhosis.     

Suspected pulmonary embolism: enhancement of pulmonary arteries at deep-inspiration CT angiography--influence of patent foramen ovale and atrial-septal defect

PURPOSE: To investigate if abnormal early contrast enhancement of the aorta and decreased attenuation of pulmonary arteries at deep-inspiration spiral computed tomographic (CT) angiography might be caused by a patent foramen ovale (PFO). MATERIALS AND METHODS: Two hundred forty-four spiral CT angiographic images of the pulmonary arteries obtained during deep inspiration in patients suspected of having pulmonary embolism (PE) were reviewed for evidence of abnormal early enhancement of the aorta. In 45 patients, enhancement of the ascending aorta was equal to or more than that of the pulmonary arteries. Nonenhanced or contrast material-enhanced echocardiography was performed in 39 of these cases. All CT images with abnormal enhancement patterns were graded for contrast quality with respect to sufficient enhancement of pulmonary arteries (four grades) at three anatomic levels: right and left main and lobar and segmental branches. In addition, all spiral CT angiographic images were evaluated concerning the diagnosis of PE and the grouping of central (main pulmonary artery to proximal lobar arteries) and peripheral (beyond proximal lobar branches) locations of emboli. Mean attenuation values of ascending aortas and main pulmonary arteries in group 1 (n = 244) were compared with those in groups 2 and 3 (n = 45) by means of the two-tailed Student t test for unpaired data (P <.05). RESULTS: Attenuation values for ascending aortas in group 1 were significantly lower than those in groups 2 and 3 (P <.001). Attenuation values in main pulmonary arteries were significantly higher in group 1 than in groups 2 and 3 (P <.001). Echocardiographic images showed an intracardiac right-to-left shunt in all 39 cases with abnormal contrast dynamics in the CT study (16% of the whole study population). Three patients had an atrial-septal defect, and 36 had a PFO. Images with a shunt had good (9%), intermediate (37%), fair (33%), and poor (23%) contrast of the pulmonary arteries. Sufficient vessel contrast for the diagnosis of PE could not be achieved in 27 of 45 patients with a shunt, but severe central PE could be ruled out. PE could be diagnosed in 31% of the 244 images, 58% were negative, and 11% were indeterminate. CONCLUSION: A PFO may frequently lead to insufficient attenuation of the pulmonary arteries, which potentially limits the diagnosis of PE if the examination is performed during deep inspiration.     

能谱联合迭代重建在重度肝硬化双低扫描中的应用价值

目的 探讨能谱单能量成像联合前后置适应性统计迭代重建-V（ASIR-V）技术对重度肝硬化上腹部双低扫描的应用价值。方法 前瞻性收集拟行上腹部增强扫描的肝硬化患者126例,按照随机数表法分为3组,每组42例。其中对照组采用120 kV、420 mg I/kg对比剂含碘量和FBP重建;能谱组和联合组均采用能谱扫描,300 mg I/kg,其中能谱组为60 keV单能量图像联合0前置和40% ASIR-V后置重建获得,联合组40%前置,并根据keV和后置比例,进一步分为2个亚组：50 keV联合50% ASIR-V后置和60 keV联合40% ASIR-V后置。图像客观指标及辐射剂量比较采用方差分析,图像主观指标比较采用秩和检验。结果 除门脉期肝实质外,能谱组和联合组的CT值和CNR值较对照组差异有统计学意义（F=4.293~13.134,P<0.05）,且两两比较,50 keV联合50% ASIR-V后置组高于对照组（q=1.825~3.736,P<0.05）。噪声和脏器总体图像质量评分差异无统计学意义,肝血管分支的显示50 keV联合50% ASIR-V后置组高于其余3组（Z=2.793~6.328,P<0.05）。联合组的辐射剂量低于能谱组、对照组（q=-4.879~-2.531,P<0.001）。结论 能谱单能量成像联合前后置ASIR-V技术在保证图像质量的前提下,对重度肝硬化患者上腹部增强扫描可降低对比剂量和辐射剂量。     

Low mechanical index contrast-enhanced ultrasound better reflects high arterial perfusion of liver metastases than arterial phase computed tomography

RATIONALE AND OBJECTIVES: We investigated whether observing the arterial vascularization of liver metastases by contrast-enhanced ultrasound with low mechanical index (low-MI) imaging offers additional diagnostic information for the characterization of the liver lesions. METHODS: Twenty nine patients with untreated liver metastases of different primaries were examined. Measurements were performed using a low frame rate, low-MI pulse inversion technique after injection of 2.4 mL SonoVue. The relative maximum signal intensity of the liver lesions related to the normal liver tissue was quantified. Ultrasound findings were compared with contrast-enhanced, dual-phase computed tomography (CT) using a pattern-based classification scheme. RESULTS: Compared with contrast-enhanced CT, this modality better detects arterial perfusion. Metastases, even those usually considered hypovascularized, often showed homogeneous enhancement (66%) and higher arterial vascularization than normal liver tissue. CT did not show a comparable vascularization pattern (P < 0.001) or any similarly early signal intensity (P < 0.001). CONCLUSIONS: Contrast-enhanced CT may not be able to visualize short-lasting but large differences of the arterial perfusion of liver metastases, as does contrast-enhanced low-MI ultrasound. This offers new methods for their characterization and for monitoring of therapeutic effects.     

Non-small cell lung cancer: prospective comparison of integrated FDG PET/CT and CT alone for preoperative staging

PURPOSE: To evaluate prospectively the accuracy of integrated positron emission tomography (PET) and computed tomography (CT) with use of fluorodeoxyglucose (FDG), compared with that of stand-alone CT, for the preoperative staging of non-small cell lung cancer, with surgical and histologic findings used as the reference standard. MATERIALS AND METHODS: Institutional review board approval and patient informed consent were obtained. From November 2003 to February 2004, 106 patients (78 men, 28 women; mean age, 56 years) with non-small cell lung cancer underwent curative surgical resection (tumor resection and lymph node dissection) after stand-alone CT followed by integrated FDG PET/CT. Tumor stages were determined by using the TNM and American Joint Committee on Cancer staging systems. Histopathologic results served as the reference standard. Statistically significant differences in tumor staging between integrated PET/CT and stand-alone CT were determined with P < .05 obtained by using the McNemar test or with a generalized estimating equation. RESULTS: The primary tumor was correctly staged in 84 patients (79%) at stand-alone CT and in 91 patients (86%) at integrated FDG PET/CT (P = .25). For the depiction of malignant nodes, the sensitivity, specificity, and accuracy of CT were 70% (23 of 33 nodal groups), 69% (248 of 360), and 69% (271 of 393), respectively, whereas those of PET/CT were 85% (28 of 33), 84% (302 of 360), and 84% (330 of 393) (P = .25, P < .001, and P < .001, respectively). There were 112 false-positive interpretations at CT for 54 hilar, 16 subcarinal, 29 paratracheal, 10 subaortic, and two pulmonary ligament nodal groups and one upper paratracheal group, compared with only 58 false-positive interpretations at PET/CT for 32 hilar, seven subcarinal, 13 lower paratracheal, and six subaortic nodal groups. There were 10 false-negative interpretations at CT for four hilar, two lower paratracheal, and two subcarinal nodal groups, one prevascular and retrotracheal group, and one inferior pulmonary group, but only five false-negative interpretations at PET/CT (one each for paratracheal, subaortic, subcarinal, inferior pulmonary, and hilar nodal groups). CONCLUSION: Integrated FDG PET/CT is significantly better than stand-alone CT for lung cancer staging and provides enhanced accuracy and specificity in nodal staging.