多层CT灌注成像诊断周围型肺癌及与微血管密度对照研究

目的:探讨多层螺旋CT(MSCT)灌注成像技术诊断肺癌的临床价值及其与肿瘤微血管密度(MVD)的相关性。方法:利用16层MSCT灌注成像技术前瞻性研究38例经手术病理证实的肺肿瘤(周围型肺癌25例,肺良性肿块13 例),并与25例肺癌的免疫组化法MVD进行相关性研究。采用Perfusion 2体部肿瘤灌注软件包分析以下灌注参数:血液流速(BF)、血流量(BV)、平均通过时间(MTT)和表面通透性(PS)。结果:肺癌各项CT灌注参数值均高于肺良性肿块, 其中MTT和PS值在两组之间差异有显著性意义(P<0．05),BV值差异有极显著性意义(P<0．01);肺癌的MVD明显高于肺良性肿块(P<0．05),肺腺癌MVD高于肺鳞癌(P<0．05);肺癌仅BV值与其MVD呈正相关性(r=0．852,P< 0．01)。结论:MSCT灌注成像有助于周围型肺癌的诊断及与良性肿瘤的鉴别诊断,其病理基础与肿瘤微血管密度有关。     

双源CT灌注成像在颈部淋巴结病变中的初步研究

目的 探讨双源CT灌注成像技术在颈部淋巴结病变定性诊断中的价值.资料与方法 对40例颈部肿大淋巴结行CT灌注扫描,将其中34例有完整手术病理结果的病例根据其良恶性分为两组,分析良恶性淋巴结的时间密度曲线(TDC)及灌注参数的特点,比较各灌注参数的统计学差异.结果 良性淋巴结组TDC以缓升型为主(87.5%),甲状腺癌转移淋巴结TDC以速升速降型为主(62.5%),淋巴瘤TDC以低平型为主(60%),其他癌(鳞癌、腺癌)转移淋巴结TDC多呈速升缓降型(62.5%);恶性淋巴结组的血流量(BF)、血容量(BV)、Patlak血容量(P-BV)、达峰时间(TTP)及强化值(EV)均高于良性组,其差异有统计学意义(P<0.05).结论 颈部良、恶性淋巴结病变及不同类型恶性淋巴结病变的CT灌注特点不同,CT灌注成像技术对颈部淋巴结病变的定性诊断有重要的应用价值.     

多层CT灌注成像在肺内肿瘤诊断中的应用

目的 研究16层螺旋CT灌注成像在鉴别肺内肿瘤中的价值.方法 对63例肺部单发病变进行前瞻性分析,采用Philips Brilliancel6排螺旋CT对肿块行灌注扫描.用CT灌注软件包进行分析.结果 高及中分化组的灌注值(PV),最高增强值(PE)及血容量(BV)值明显高于低分化及未分化组肺癌,差异均有统计学意义(分别为P<0.01,P<0.01,P<0.05).肺部病变PV、PE、BV值为炎性>恶性>良性,其中PV、PE值各组问差异均有统计学意义,而BV值仅炎性病变与良性病变之间差异有统计学意义(P<0.01);如果以150.05).中央型与周围型肺癌各灌注参数也无统计学意义(P>0.05).结论 螺旋CT灌注成像对鉴别肺内恶性、良性及炎性病变及判别肺癌恶性程度有较大价值.     

CT能谱成像在原发性肺癌与肺转移瘤鉴别诊断中的价值

目的探讨CT能谱成像在原发性肺癌与肺转移瘤鉴别诊断中的价值。方法对平扫发现肺部肿块或结节的患者行GE能谱CT增强扫描,其中原发性肺癌32例,肺转移瘤23例。在动脉期和静脉期40~70ke V单能量条件下,分别测量并比较两组病灶的平均CT值、碘浓度、水浓度及能谱曲线差异。结果在动脉期,原发性肺癌组的平均CT值、能谱曲线斜率、碘浓度低于肺转移瘤组,差异有统计学意义(P0.05),两组间水浓度差异无统计学意义(P0.05);在静脉期,原发性肺癌组与肺转移瘤组间各能谱参数差异无统计学意义(P0.05)。单能量图像可以更好的显示肿块内及其周围血管的情况。另中心型肺癌可以导致受累肺组织血流灌注减低。结论能谱CT在原发性肺癌和肺转移瘤的鉴别诊断中有一定的临床价值。     

CT棘突征对周围型肺癌的诊断价值

目的：探讨肺内孤立结节球形状棘突CT征对周围型肺癌的诊断与鉴别诊断价值。方法：47例经临床手术病理和抗炎治疗后证实的孤立型肺结节中，周围型肺癌32例，肺良性病变15例。所有病例从肺尖至肺底扫描，层厚8mm，依病灶大小，加扫薄层4mm，部分病例（35例）经肘静脉注射对比剂对病灶行增强薄层扫描。对棘突CT征与周围肺癌CT表现的病理基础及鉴别诊断进行了讨论。结果：周围型肺癌的棘突CT征发生率为66%(21/32),比其它肺良性病变20%(3/15)高。结论：肺内孤立结节灶棘突CT征对周围型肺癌的诊断与鉴别诊断具有重要价值，是诊断肺癌的一个指征。     

CT灌注成像在急性自发性高血压性脑出血中的应用

目的 应用CT灌注成像(CT perfusion,CTP)对急性自发性高血压出血性脑卒中(acute spontaneously hypertensive intracerebral hemorrhage,shICH)血肿周围脑血液动力学变化进行定量研究,验证血肿周围是否存在缺血半暗带.方法 对26例(男22例,女4例,年龄33～74岁,平均55.08岁)临床及CT确诊为幕上shICH患者行CTP检查,自发病到灌注扫描的时间为8～19h,平均14.88h.以血肿最大层面为参照,测量血肿内部、血肿周围、远隔区及对侧镜像区脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MTT),并计算相对灌注参数值rCBF、rCBV、rMTT(患侧/健侧).结果 shICH血肿灌注参数伪彩图从血肿中心到外周色差呈阶梯样分布.血肿周围组CBV值为(1.61±1.53)ml·100g-1、CBF值为(16.48±17.38)ml·100g-1·min-1),低于对侧镜像区(ZCBV=-2.603、ZCBF=-4.178,P＜0.05);MTT值为(9.12±2.57)s,较对侧镜像区延长(t=4.747,P＜0.05).方差分析显示血肿内部、血肿周围组及远隔区组灌注参数MTT及相对值rCBF、rCBV、rMTT均数间差异有统计学意义(FMTT=9.043、FrCBV=38.031、FrCBF=25.023、FrMTT=12.486,P＜0.05),进一步LSD分析,血肿周围组与远隔区组MTT、rMTT、rCBF差异有统计学意义(P＜0.05),但两组间rCBV值无统计学差异(P＞0.05).且秩和检验显示血肿周围组CBF明显低于远隔区组(Z=2.288,P＜0.05),但两组间CBV均值差异无显著性(Z=-0.357,P＞0.05).结论 CTP可反应shICH血肿周围低灌注状态,但没有证据显示存在缺血半暗带.     

周围型肺腺癌增强CT与血管生成的相关研究

目的　探讨周围型肺腺癌CT增强表现与血管生成的关系。材料与方法　对 2 9例周围型肺腺癌标本进行S P法免疫组织化学染色 ,检测VEGF表达 ,并且用FVⅢ RA标记微血管内皮细胞来检测微血管密度 (MVD)。全部病例CT增强的同时有 17例进行了 3min内的动态CT增强扫描。结果　 2 9例周围型肺腺癌组织中的MVD与血管内皮生长因子 (VEGF)呈正相关 (r=0 .76 ) ,有淋巴结转移组的MVD、VEGF强表达率明显高于无淋巴结转移组(P <0 .0 5 ) ,Ⅱ期组的MVD、VEGF强表达率明显高于Ⅰ期组 (P <0 .0 1) ;其中 17例 3min内的CT增强值与MVD呈正相关 (r=0 .73～ 0 .84 ) ;VEGF强表达组的CT增强值显著高于弱表达组 (P <0 .0 5 )。结论　周围型肺腺癌在3min内的CT增强值与血管生成呈正相关 ,可能反映肺癌的恶性程度     

肺动脉高压和外周型慢性血栓栓塞性肺高压的肺灌注特点:31例病人双能CT分析

正摘要目的比较肺动脉高压(PAH)与外周型慢性血栓栓塞性肺高压(p CTEPH)双能CT肺灌注的特点。方法 31例病人(第1组为19例PAH;第2组为12例p CTEPH)接受双能量胸部CTA扫描,并进行扫描后诊断及灌注图像的重组。对灌注参数的分析进行至肺段水平。22例病人行通气-灌注(V/Q)核素闪烁扫描(其中第1组13例,第2组9例)。结果CT灌注异常的病人中,第1组阳性率为52.6%,第2组阳性率为100%,两者差异具有统计学意义(P=0.005 1);且灌注异常的表现类型在2组间差异具有统计学意义(P0.000 1):     

甲状腺结节MSCT灌注成像与微血管密度相关性

目的 研究不同性质甲状腺结节CT灌注成像与微血管密度(MVD)的相关性.方法 随机选取52例甲状腺病变患者,良性组40例,恶性组12例,均采用常规CT平扫和同层动态灌注扫描,计算出血流量(BF)、血容量(BV)、表面通透性(PS)、平均通过时间(MTT)及达峰时间(TTP),良恶性甲状腺结节CT灌注参数各值分别与各组病例术后病理免疫组织化学染色的MVD高倍镜下(×400)计数值进行Pearson相关分析,良性组及恶性组甲状腺结节CT灌注参数及MVD采用t检验.结果 良、恶性甲状腺结节CT灌注参数BV值分别为(13.97 ±11.34)ml/100 g、(22.89±11.56)ml/100 g,良、恶性甲状腺结节BV差异有统计学意义(t=2.211,P=0.034 ＜0.05),BF、TTP、PS、MTr差异均无统计学意义(P =0.234、0.112、0.614、0.709);良、恶性甲状腺结节的MVD间存在显著差异(t=7.621,P=0.000 ＜0.001);良性组PS值与MVD间呈正相关(r=0.404,P=0.05),恶性组PS值与MVD间呈负相关(r=-0.601,P=0.039 ＜0.05),其余各指标BF、BV、TIP、MTT与MVD间均无相关性.结论 CT灌注成像可对甲状腺结节微血管血流动力学状况进行量化评估,其各种灌注参数中以BV值对甲状腺良恶性病变的鉴别诊断价值最大,良、恶性甲状腺结节CT灌注参数PS与MVD具有良好的相关性,对术前间接评价肿瘤的血管生成及良恶性有重要价值.     

肺周围型小结节的外科诊治分析(附122例报告)

目的 探讨肺周围型小结节(≤2cm)的诊断方法和外科治疗效果.方法 回顾性分析2005年1月-2010年10月收治的122例肺周围型小结节患者的临床资料,均经手术切除,病理诊断明确.结节直径1～2cm 101例,＜lcm 21例.术前所有患者常规行多层螺旋CT增强扫描(MSCTA)检查,52例行PET/CT检查,49例行经皮CT定位肺结节穿刺活检(CTNB).比较3种检查方法诊断肺癌的敏感性、特异性和诊断准确率.结果 术后病理示122例患者中良性病变29例(23.8％),恶性病变93例(76.2％).85例非小细胞肺癌中仅56例(65.9％)为Ⅰ a期早期肺癌,12例(14.1％)存在肺门、纵隔淋巴结转移.MSCTA的诊断准确率、敏感性、特异性分别为80.3％、81.7％、75.9％,与PET/CT(分别为84.6％、86.5％、80.0％)比较差异无统计学意义(P＞0.05).CTNB的诊断准确率、敏感性、特异性分别为91.8％、88.6％、100.0％,仅特异性高于MSCTA(P=0.045),余差异无统计学意义(P＞0.05).结论 MSCTA检查是鉴别肺周围型小结节良恶性的首选无创诊断方法,可疑肺癌者应积极手术治疗,倾向良性病变者可选择性进行CTNB检查.术前仔细分析CT片以明确病灶的空间位置,必要时结合CT引导下经皮肺穿刺活检是提高术中查找肺结节的速度和准确度的重要手段.     

双源CT双能量肺灌注成像的初步观察

目的 评价双源CT双能量扫描肺灌注成像的临床应用价值.方法 选择2007年5月至8月临床怀疑肺部疾病的连续54例患者行肺部增强双能量扫描,按照肺部不同病变分为4组:正常组、渗出性病变组、肿块性病变组和肺栓塞组.分析不同组别之间双能量CT灌注成像的表现.结果 正常组14例,肺部双能量灌注成像表现双侧肺部灌注对称,未见明显差异.渗出性病变组10例,表现为局部灌注量降低;肿块性病变组27例,因为发生位置不同肺部灌注成像表现各异,外周性肿块表现为局部肿块区域的灌注缺损,而中央型肿块因为累及肺门血管而表现为肺段性灌注降低区或缺损区.肺栓塞组3例,表现为肺栓塞区域的灌注缺损或稀疏.结论 利用双源CT双能量扫描可以观察肺的灌注状态,尤其有利于评价中央型肺癌和肺栓塞患者肺灌注的异常.     

CT支气管征对周围型肺孤立性病灶的诊断价值

目的 探讨CT支气管征对周围型肺孤立性病灶的鉴别诊断价值.方法 对111例周围型肺孤立性病灶患者进行螺旋CT扫描并进行后处理重组,分析病灶与支气管关系类型,并进行X2检验,比较其在良、恶性病灶间的差异.结果 周围型肺孤立性病灶支气管边缘截断率在恶性病变(47/95,49.5%)明显高于良性(10/42,23.8%)(X2=7.896,P＜0.05),Ⅰ、Ⅱ型支气管充气征在恶性病变(分别为10/11、8/9)出现率高于良性(分别为1/11、1/9;X2值分别为6.975、4.818,P＜0.05),而Ⅳ型在良性病变(12/17)的出现率明显高于恶性(5/17;X2=7.390,P＜0.05);支气管在病灶边缘走行、支气管牵拉移位在良性(9/24、1/4)、恶性病灶(15/24、3/4)间差异无统计学意义(X2值分别为0.641,0.062,P＞0.05);管壁局限性增厚在恶性病变(21/22)出现率高于良性(1/22;X2=4.185,P＜0.05),而广泛性增厚在良性病变(4/7)出现率明显高于恶性(3/7;X2=8.650,P＜0.05).结论 CT支气管征对周围型肺孤立性病灶良、恶性的鉴别有重要价值.     

慢性阻塞性肺部病变患者肺部CT灌注成像特征

目的探讨慢性阻塞性肺疾病(COPD)患者肺部CT灌注成像的时间密度曲线(TDC)和灌注参数特征。方法共44例,分为COPD组25例及对照组19例。均行肺部多层螺旋CT(MSCT)动态增强扫描。图像经后处理,设定感兴趣区(右腹肺、右背肺和左腹肺、左背肺),得到各处肺组织TDC和灌注参数,包括灌注值(P),强化峰值增量(PEI),达峰值时间(TTP)和血容量(BV)。比较分析COPD组和对照组的TDC特征,以及各灌注参数的差异性。结果COPD组较对照组TDC波峰延后。各灌注参数腹背肺比率在2组无显著性差异(P>0.05)。COPD组TTP较对照组明显延长(P=0.010)。P、PEI和BV在2组无显著性差异(P>0.05)。结论CT灌注成像显示COPD患者肺部血流灌注异常主要表现为TDC波峰延后,TTP延长。     

拟似肺癌的肺结核螺旋CT表现特征及其手术病理发现

目的探讨误诊为肺癌的肺结核螺旋CT表现特征与手术病理所见的相关性。资料与方法搜集术前误诊为肺癌，但经手术病理证实为肺结核30例。全部病例均行螺旋CT扫描，回顾性地评价螺旋CT表现与手术及病理改变的关系。结果(1)25例CT表现为肿块或结节，其中密度不均21例，空洞12例，卫星病灶22例。20例行增强扫描，60％(12／20)呈外周部分或环状强化，40％(8／20)无明显强化。病理为上皮样细胞及纤维组织包裹干酪样物质。(2)5例表现为肺叶、段实变或不张，其中表现为叶、段实变3例，支气管狭窄伴肺不张2例。病变密度不均匀5例，多发小空洞4例，钙化灶2例，卫星病灶5例，2例病变周围有支气管扩张。病理为干酪灶与增殖结节融合。结论病变的形态、密度、强化特征以及卫星病灶、病变周围支气管扩张等螺旋CT征象有助于不典型肺结核与肺癌的鉴别。     

双源CT双能量肺灌注成像对肺栓塞的初步研究

目的 探讨双源CT双能量扫描肺灌注成像的临床诊断价值.方法 选择临床怀疑肺动脉栓塞30例患者行双源CT双能量扫描,生成140、80 kV和融合系数为0.3的3组数据.根据融合数据的CT肺动脉造影(CTPA)图像将患者分为肺栓塞组和正常组.采用双能量评估软件将薄层重建数据进行灌注成像分析,将双肺野分为上、中、下3部分,正常组受试者肺组织灌注定量的双侧比较行配对t检验,2组间肺组织灌注量比较行独立样本t检验,并对融合图像行MinIP,评估肺组织通气情况.结果 正常组(16例)肺灌注均匀,无明显灌注缺损及减弱,灌注定量分析显示左、右全肺的灌注量分别为(27±7)、(28±8)HU,两侧比较差异无统计学意义(t=-1.73,P＞0.05);左肺上、中、下部的灌注量分别为(23±6)、(24±6)、(28±8)HU,右肺上、中、下部灌注量分别为(26±8)、(27±8)、(28±9)HU,两侧分别比较差异均无统计学意义(t值分别为-1.91、-1.96、-1.73,P值均＞0.05).肺栓塞组(14例)CTPA图像显示肺动脉干、段及亚段充盈缺损,肺灌注成像表现为栓塞血管所支配肺野区域的灌注缺损或缺失,灌注定量分析显示全肺及中、下肺的灌注量分别为(22±5)、(22±8)、(21±8)HU,与正常组分别比较差异均有统计学意义(t值分别为-2.10、-2.32、-2.63,P值均＜0.05＝.MinIP显示通气异常区与灌注异常区具有良好的一致性.结论 双源CT双能量扫描可用于肺栓塞的诊断,有利于肺栓塞的早期发现和精确解剖定位.

Abstract：

Objective To explore the diagnostic values of dual energy lung perfusion in the diagnosis of pulmonary embolism by using dual-source CT (DSCT). Methods Thirty patients with clinically suspected pulmonary embolism underwent dual-energy scanning with dual-source CT. The scanned data were integrated into three groups including 140, 80 kV and coefficient of 0.3. According to the CT pulmonary angiography (CTPA) of the fusion data, the patients were divided into pulmonary embolism group and normal group. The thin-slice reconstruction of data was analyzed using dual-energy perfusion imaging analysis software. The lung field was divided into upper, middle and lower part to make quantitative analysis of lung tissue perfusion. Paired t-tests were used in the normal patients to compare bilateral lungs, and independent samples t-tests were applied to compare the embolism group and normal group, while minimum intensity projection images (MinIP) were utilized in the assessment of lung ventilation. Results Dual energy CT showed symmetrical homogeneous perfusion in 16 normal cases, without significant perfusion defects. Quantitative analysis showed that left and right lung perfusion were (27 ± 7) and (28 ± 8 ) HU respectively, and no significant difference was found between the two sides ( t=-1.73, P ＞0.05 ).Perfusion of the left upper, middle and lower lung was ( 23 ± 6), (24 ± 6), and (28 ± 8) HU respectively, while the perfusion of right upper, middle and lower lung was (26 ±8), (27 ±8), and (28 ±9) HU respectively, showing no statistical significant difference between the two sides (t=-1.91, -1.96,-1.73 ,P＞0.05 ). Angiography of pulmonary embolism group(14 cases)showed filling defects in the pulmonary trunk, segments and sub-segments. Pulmonary perfusion imaging showed low perfusion or defectsin lung field that dominated by embolic vessels. Quantitative analysis showed that the perfusion of the whole lung and the middle and lower lung were (22 ±5), (22 ±8), and (21 ±8) HU in the embolism group,which were significantly different from the normal group (t=-2. 10, -2.32, -2.63, P＜0.05).Minimum intensity projection images showed a good consistency of abnormal ventilation zone area and perfusion abnormalities. Conclusions Pulmonary perfusion status, especially pulmonary embolism, can be analyzed by dual energy CT scanning. It helps to early discover and precisely locate the embolism.     

Bronchial artery perfusion scintigraphy to assess bronchial artery blood flow after lung transplantation.

The bronchial arterial system is inevitably interrupted in transplanted lungs when removing the organs from the donor, but it can be reestablished by direct bronchial artery revascularization (BAR) during implantation. The purpose of this study was to visualize and quantify the distribution of bronchial artery perfusion after en bloc double lung transplantation with BAR, by injecting radiolabeled macroaggregated albumin directly into the bronchial artery system. METHODS: BAR was performed using the internal mammary artery as conduit. Patients were imaged 1 mo (n = 13) or 2 y (n = 9) after en bloc double lung transplantation with BAR. Immediately after bronchial arteriography, 100 MBq macroaggregated albumin (45,000 particles) were injected through the arteriographic catheter. Gamma camera studies were then acquired in the anterior position. At the end of imaging, with the patient remaining in exactly the same position, 81mKr-ventilation scintigraphy or conventional intravenous pulmonary perfusion scintigraphy or both were performed. Images were evaluated by visual analysis, and a semiquantitative assessment of the bronchial arterial supply to the peripheral parts of the lungs was obtained with conventional pulmonary scintigraphy. RESULTS: The bronchial artery scintigraphic images showed that the major part of the bronchial arterial flow supplied central thoracic structures, but bronchial artery perfusion could also be demonstrated in the peripheral parts of the lungs when compared with conventional pulmonary scintigraphy. There were no differences between scintigrams obtained from patients studied 1 mo and 2 y post-transplantation. CONCLUSION: Total distribution of bronchial artery supply to the human lung has been visualized in lung transplant patients. This study demonstrates that this nutritive flow reaches even the most peripheral parts of the lungs and is present 1 mo as well as 2 y after lung transplantation. The results suggest that bronchial artery revascularization may be of significance for the long-term status of the lung transplant.     

螺旋CT灌注成像结合动态增强扫描对肺内结节/肿块的诊断价值研究

目的 探讨螺旋CT灌注成像与常规动态增强扫描在肺内结节或肿块鉴别诊断中的应用价值.资料与方法 经病理或临床证实的肺内结节或肿块患者81例,行CT灌注扫描及常规动态增强扫描,计算病灶感兴趣区的血流量(BF)、血容量(BV)、平均通过时间(MTT)和表面渗透性(PS)以及描绘时间-密度曲线(TDC),比较三组结节或肿块之间的区别.结果 恶性和活动性炎性结节或肿块的BV及PS值明显高于良性结节(P<0.05).三组结节或肿块间BF和MTT值无统计学差异.恶性与活动性炎性结节或肿块之间各灌注值有较明显重叠.三组结节或肿块的(TDC)不同.结论 螺旋CT灌注成像与常规动态增强扫描结合有利于肺内结节或肿块的鉴别诊断.     

Accuracy of image coregistration of pulmonary lesions in patients with non-small cell lung cancer using an integrated PET/CT system.

The purpose of this study was to evaluate the accuracy of image coregistration of PET and CT (PET/CT) images in patients with lung lesions and the influence of the breathing protocol during CT. METHODS: Seventy-five patients with a solitary and well-circumscribed pulmonary lesion (non-small cell lung cancer; size, 10-30 mm) underwent PET/CT on a combined scanner. CT was acquired during shallow breathing in 37 patients and during normal expiration (i.e., the level reached when the patient exhaled without forcing expiration and then held the breath) in 38 patients. The volume of interest of each lesion was defined separately on PET and CT images, and the geometric center of gravity (COG) was assessed. The distance of COGs between the PET image and the CT image was measured. All lesions were classified according to 4 lung regions: apical, peripheral, central, and lung base. The mismatch between COG(PET) and COG(CT) was compared between regions and patient groups using a 2-way ANOVA with the Bonferroni-Dunn test for post hoc comparisons. RESULTS: The range of COG distance between PET and CT was 1.7-5.4 mm in the apex, 0.5-14.7 mm in the periphery, 0.7-5.9 mm centrally, and 2.9-11.3 mm in the lung base. The match between PET and CT was significantly better in patients who had the CT scan obtained during normal expiration than in patients who performed shallow breathing during CT scanning (P = 0.024). No reciprocal effects were found (interaction P = 0.76). The mismatch of lesions depends significantly on lung region (P < 0.0001). Post hoc analysis showed a significant difference between the upper 2 regions and the lower 2 regions (all P < or = 0.002) but not between the apex and the central region (P = 0.95) and between the peripheral region and the lung base (P = 0.15). The lesion size had no influence on the COG mismatch. CONCLUSION: The match of lung lesions in coregistered PET/CT images is better when acquiring the CT scan during normal expiration. The coregistration accuracy is better in the upper and central parts of the lung. The normal expiration protocol is suggested to be superior to shallow breathing during CT scanning.     

Ⅰ期周围型肺腺癌CT灌注成像临床研究

目的探讨MSCT灌注成像评价临床Ⅰ期周围型肺腺癌影像特征的价值。方法对72例患者行MSCT灌注扫描,用多元相关分析探讨灌注参数与影像特征的关系,再分组进行趋势检验。结果灌注参数与周围型肺腺癌影像特征相关,血流量(BF)和强化峰值(PEI)随分化程度减低而降低(P值分别为0.01与0.024);有淋巴结转移组的BF和PEI明显低于无淋巴结转移组(P值分别为0.000与0.003);术后转移组BF值明显低于未转移组(P=0.000)。结论 MSCT灌注成像通过无创性评价血管生成的方式和程度,间接反映肿瘤分化程度,从而预测淋巴结转移和术后转移的可能性,是判断周围型肺腺癌生物学行为及预后的良好指标。     

Clinical feasibility of pulmonary perfusion analysis using dynamic computed tomography and a gamma residue function

Purpose

To create and determine the clinical feasibility of a model based on dynamic computed tomography (CT) and a bolus injection of iodine contrast medium for evaluation of pulmonary perfusion for healthy individuals and for patients with lung diseases.

Materials and methods

We analyzed pulmonary perfusion by means of dynamic 16-row multidetector CT scanning with a gamma residue function with adding a linear component (extended gamma function model) for 20 healthy individuals and in five patients.

Results

Four types of the time–attenuation curve (TAC) were identified for the peripheral lung. Although the TACs of most pixels for the peripheral lung comprised a single peak or a single-peak followed by another increase, no peak was observed for a small proportion of pixels, which either increased linearly or resulted in a delayed peak for healthy subjects. The ratios of these linearly increasing or delayed peak types of lung fields increased for pathological lungs. The analytical results for pathological cases showed that changes in lung perfusion, difficult to identify using only CT imaging, could be detected.

Conclusions

The extended gamma function model adequately evaluated pulmonary perfusion not only for normal regions, but also for structurally abnormal regions. Regional changes in perfusion could be evaluated by use of our model, and we confirmed its clinical feasibility for pulmonary perfusion analysis.