基于双能量CT增强图像的列线图预测早期声门型喉癌术后复发

目的探讨基于双能量CT(DECT)增强图像的列线图预测早期声门型喉癌(EGC)术后无复发生存期的价值。方法回顾性分析2015年1月至2018年7月天津市第一中心医院经手术病理证实的EGC患者的临床病理和DECT资料。共入组178例患者, 男162例、女16例, 年龄44～86(62±9)岁。对所有患者进行随访, 根据随访资料, 分为复发组(n=32)和无复发组(n=146)。2组间临床病理资料和碘图定量参数虚拟平扫CT值、碘浓度及标准化碘浓度(SIC)的比较采用χ2检验、独立样本t检验或Mann-WhitneyU检验。用X-tile软件进行2组间定量资料生存相关截断值的筛选。采用Kaplan-Meier法绘制无复发生存曲线, 使用log-rank法检验生存率差异。将有差异的变量纳入Cox比例风险回归模型筛选术后无复发生存期的独立影响因素, 基于多因素Cox分析, 绘制预测1、2和5年无复发生存率的列线图。用C指数、校准曲线和决策曲线评估联合DECT参数及T分期的列线图模型的预测效能及临床有效性。结果患者随访时间2～63个月, 中位随访时间为24.3个月。复发组与无复发组间肿瘤T分期差异...     

双能CT对AIS血管内治疗后早期颅内出血的诊断价值

【摘要】目的：评价双能CT（DECT）对急性缺血性脑卒中（AIS）患者血管内治疗后早期颅内出血（ICH）和对比剂外渗的鉴别诊断价值。方法：2017年11月－2019年2月对在本院接受血管内治疗的AIS患者在术后2h内行头颅DECT扫描（80kVp和Sn150kVp）得到的混合能量图像，经后处理获得虚拟平扫图（VNC）及碘覆盖图（IOM），以术后24~48h的常规CT（44例）或MR磁敏感加权血管成像（SWAN）（5例）的诊断结果作为参照标准（常规CT显示梗死区出现高密度影或SWAN图像显示低信号影即为出血），评价DECT图像（混合图像+VNC+IOM）对AIS患者血管内治疗后ICH的早期诊断效能。结果：符合纳入条件的49例AIS患者中15例DECT诊断为颅内出血合并对比剂外渗，全部经随访图像证实；34例诊断为对比剂外渗，随访证实30例，余4例随访图像提示出血性转化。DECT诊断早期ICH的敏感度、特异度及符合率分别为78.95%（15/19）、100%（45/45）和93.75%（60/64），阳性和阴性预测值分别为100%（15/15）和91.84%（45/49）。结论：双能CT可诊断AIS患者经血管内治疗后早期ICH并指导临床治疗。     

内镜黏膜下剥离术治疗早期胃癌中脉管癌栓相关因素分析

目的分析内镜黏膜下剥离术(ESD)治疗早期胃癌(EGC)患者中脉管癌栓的相关因素。方法回顾性分析自2006年11月至2016年1月经ESD治疗的261例EGC患者的临床病理资料,对脉管癌栓阳性患者的存活情况进行随访,并分析影响脉管癌栓的相关因素。结果本研究261例EGC患者中,9例患者脉管癌栓阳性,阳性率为3.4%(9/261)。其中,7例追加外科手术治疗,2例未接受手术治疗。随访时间31~108个月,患者均获得长期存活,存活率为100.0%。脉管癌栓与肿瘤分化程度、浸润深度具有相关性。结论分化程度差、黏膜下侵犯的EGC患者接受ESD治疗时应警惕脉管癌栓的发生。     

内镜超声对早期胃癌内镜下治疗的指导价值

目的探讨内镜超声（EUS）对内镜下黏膜切除术（EMR）及内镜黏膜下剥离术（ESD）治疗早期胃癌（EGC）的指导价值。方法 56例EGC患者事先行EUS检查后,行EMR或ESD治疗,作为研究组;未行EUS检查的32例行EMR或ESD治疗的EGC患者作为对照组。统计EUS对病灶大小、浸润深度及淋巴结转移的检查情况,比较两组病灶切除情况、手术并发症、5年复发率及生存率。结果研究组56例患者经EUS检查后,发现m癌36例,sm癌20例;与病理结果对照,m癌诊断符合率94.4%,sm癌符合率90.0%;无论是EMR还是ESD,研究组的整块切除率、完整切除率及治愈性切除率均显著高于对照组（P〈0.05或P〈0.01）,非治愈性切除率显著低于对照组（P〈0.05）。研究组术后5年内复发率（3.57%）显著低于对照组（18.75%）（P〈0.05）,5年存活率（98.21%）显著高于对照组（87.50%）（P〈0.05）。结论 EUS有助于EGC患者EMR或ESD适应证的选择,能指导术者对切除范围的了解,保证切除效果和安全性,提高了EGC内镜下治疗效果。     

应用双能CT的新重建算法降低早期胃癌分期的差异率:初步研究

正摘要目的评估应用双能CT(DECT)的高级单能量影像(AMEI)在早期胃癌(EGC)中的潜在价值。方法本研究回顾性分析31例EGC病人(男19例,女12例;年龄38~81岁,     

双能量CT在鉴别眼眶炎性假瘤和MALT淋巴瘤中的应用初探

目的:初步探讨双能量CT (DECT)在鉴别特发性眼眶炎性假瘤(IOIP)与黏膜相关淋巴组织(MALT)淋巴瘤中的应用价值,明确可用于鉴别两者的DECT参数.方法:回顾性分析经病理证实的5例IOIP患者及5例MALT淋巴瘤患者的DECT检查资料.对DECT参数进行独立样本f检验,绘制受试者操作特征(ROC)曲线,明确鉴...     

早期胃癌75例临床病理特征与预后分析

目的探讨早期胃癌(EGC)临床病理特征及预后。方法回顾性分析75例早期胃癌临床、病理及预后资料。结果 EGC发病高峰为42～63岁,以男性多见。大体分型以凹陷型为主,组织学分型以高、中分化腺癌为主。部位以幽门为主。癌浸润至黏膜下层病例多于黏膜层。14.67%患者伴胃周淋巴结转移。5年存活率95.52%。结论 EGC诊断首选胃镜及活检组织病理检查,根治性手术治疗是最佳方法,术后应对有可能复发的患者进行预防性化疗,淋巴结的转移对EGC预后影响最大。     

双能CT联合MRI诊断手肌腱损伤的效率分析

【摘要】目的：探讨双能量CT（DECT）联合MRI对手肌腱损伤的诊断价值。方法：回顾性分析经关节镜证实的30例肌腱损伤患者(75处病灶)及10例正常侧肌腱（140处肌腱）的DECT及MRI检查资料,对比分析DECT、MRI及两者联合应用的诊断效率。结果：DECT、MRI及两者联合应用,对手肌腱损伤诊断的敏感度分别为84.0%、90.7%和94.7%,特异度分别为 98.6%、99.3% 和 99.3%,符合率分别为 93.5%、96.3%和97.7%。结论：DECT、MRI检查对手肌腱损伤的诊断都具有较高的敏感度和特异度,而联合检查可以有效地提高诊断符合率。     

手术治疗非小细胞肺癌60例临床观察

目的：探讨手术治疗非小细胞肺癌的临床效果。方法：采用回顾性分析的方法,分析我院收治的60例非小细胞肺癌患者的临床资料。结果：60例非小细胞肺癌患者手术治疗,术后进行1～5年的随访,随访率100％,1年生存率45例（75％）,3年生存率30例（50％）,5年生存率12例（20％）。结论：通过对患者的病理类型、病理分期和手术方式进行合理的分析,同时进行术后处理及放疗或化疗,对患者的临床疗效及生存率具有重要的临床意义。     

双源双能量CT肺动脉成像辐射剂量与图像质量的比较研究

_目的：比较第一代双源双能量 CT（DECT）与第二代双源双能量 CT 肺动脉成像（CTPA）的辐射剂量和图像质量。方法：120例疑似肺栓塞患者行 DE-CTPA 检查,其中40例患者行第二代双源 DECT 80/Sn140 kV 检查（第一组）,40例患者行第二代双源 DECT 100/Sn140 kV 检查（第二组）,40例患者行第一代双源 DECT 140/80 kV 检查（第三组）。测量每例患者肺动脉主干、肺动脉段、空气及背部脂肪的 CT 值及标准差,对肺动脉图像进行主观评分,计算图像信噪比（SNR）、对比噪声比（CNR）及每例患者的有效剂量（ED）。结果：第一组肺动脉平均 CT 值[（354．1±73．4）HU]明显高于第二组[（290．1±73．1）HU,P＜0．001]和第三组[（303．9±73．3）HU,P＜0．001],但第二组与第三组差异无统计学意义（P＝0．399）;第三组平均 SNR（24．8±8．4）低于第一组（40．4±12．9,P＜0．001）和第二组（44．6±12．9,P＜0．001）,但第一组与第二组差异无统计学意义（P＝0．115）。第一组平均 CNR（435．3±77．7）明显高于第二组（355．8±77．8,P＜0．001）和第三组（384．8±79．0,P＝0．005）,但第二组与第三组差异无统计学意义（P＝0．100）。三组图像主观质量评分差异无统计学意义（P＞0．05）。第一组的 ED[（1．2±0．3）mSv]明显低于第二组[（2．4±0．7）mSv]和第三组[（3．0±0．7）mSv],差异均有统计学意义（P＜0．05）。结论：第二代双源 DECT 80/Sn140 kV 扫描方案可在大幅度降低辐射剂量的同时获得满足诊断需求的图像。     

联合CT图像特征和双能CT定量参数对甲状腺乳头状癌颈部淋巴结转移的诊断价值

目的:探讨CT图像特征联合双能CT定量参数对甲状腺乳头状癌（PTC）颈部淋巴结转移的诊断价值。方法:回顾性分析2017年6月至2019年6月于南京医科大学第一附属医院经手术病理证实的103例PTC患者的术前双能CT图像。参考2002年美国头颈外科协会的淋巴结分区标准,将颈部淋巴结分为7区,采用淋巴结影像病理亚区对照的方...     

基于动脉自旋标记灌注参数和临床病理特征的列线图预测中晚期鼻咽癌放化疗疗效

目的探讨基于动脉自旋标记(ASL)MRI灌注参数和临床病理特征构建的列线图对中晚期鼻咽癌(ANPC,Ⅲ和Ⅳ期)放化疗疗效的预测价值。方法前瞻性纳入2018年6月至2021年1月江南大学附属医院经病理证实的70例ANPC患者,在放化疗前行鼻咽MR平扫、ASL和增强扫描,放化疗疗程结束后1周内行常规MR复查。记录放化疗前的ASL灌注参数肿瘤血流量(TBF)和临床病理特征,并在T1WI图像上测量肿瘤最大径(MD)。根据实体瘤疗效评价标准将患者分为放化疗有效组(48例)和无效组(22例)。采用独立样本t检验比较有效组与无效组间TBF、年龄、MD的差异,以χ²检验比较两组间性别、临床分期、病理类型的差异;使用二元逻辑回归分析分别构建临床病理模型和TBF、临床病理联合模型,并建立联合模型的列线图。采用受试者操作特征(ROC)曲线获得模型的诊断效能,采用DeLong法比较模型间曲线下面积(AUC)的差异。建立列线图的校准曲线,并获得一致性指数(C指数)。结果放化疗有效组和无效组的TBF分别为(113±9)、(97±14)ml·100 g^-1·min^-1,差异有统计学意义(t=5.17,P<0.001),放化疗有效组的MD值小于无效组,差异有统计学意义(t=-2.24,P=0.028)。2组间临床分期和病理类型差异均有统计学意义(χ²值分别为12.21、12.95,P均<0.001)。通过逻辑回归分析纳入3个独立预测因子,包括TBF(OR值7.749)、临床分期(OR值0.129)及病理类型(OR值5.228)。TBF模型预测放化疗疗效的AUC为0.843,灵敏度为87.5%,特异度为72.7%;临床病理模型的AUC为0.822,灵敏度为80.2%,特异度为59.1%;联合模型列线图的AUC为0.893,灵敏度为81.2%,特异度为90.9%。联合模型列线图与TBF模型的AUC比较差异无统计学意义(Z=1.23,P=0.215),但高于临床病理模型的AUC,差异有统计学意义(Z=2.47,P=0.031)。校准曲线显示联合模型列线图预测值与临床实际观察值间具有较好的一致性,C指数为0.892。结论TBF、临床分期和病理类型是ANPC患者放化疗疗效的独立预测因子,基于此3项因素构建的列线图在预测放化疗疗效方面具有较高的效能。     

Correlation analysis of dual-energy CT iodine maps with quantitative pulmonary perfusion MRI

AIM:To correlate dual-energy computed tomography(DECT) pulmonary angiography derived iodine maps with parameter maps of quantitative pulmonary perfusion magnetic resonance imaging(MRI).METHODS:Eighteen patients with pulmonary perfusion defects detected on DECT derived iodine maps were included in this prospective study and additionally underwent time-resolved contrast-enhanced pulmonary MRI [dynamic contrast enhanced(DCE)-MRI].DCE-MRI data were quantitatively analyzed using a pixel-by-pixel deconvolution analysis calculating regional pulmonary blood flow(PBF),pulmonary blood volume(PBV) and mean transit time(MTT) in visually normal lung parenchyma and perfusion defects.Perfusion parameterswere correlated to mean attenuation values of normal lung and perfusion defects on DECT iodine maps.Two readers rated the concordance of perfusion defects in a visual analysis using a 5-point Likert-scale(1 = no correlation,5 = excellent correlation).RESULTS:In visually normal pulmonary tissue mean DECT and MRI values were:22.6 ± 8.3 Hounsfield units(HU);PBF:58.8 ± 36.0 mL/100 mL per minute;PBV:16.6 ± 8.5 mL;MTT:17.1 ± 10.3 s.In areas with restricted perfusion mean DECT and MRI values were:4.0 ± 3.9 HU;PBF:10.3 ± 5.5 mL/100 mL per minute,PBV:5 ± 4 mL,MTT:21.6 ± 14.0 s.The differences between visually normal parenchyma and areas of restricted perfusion were statistically significant for PBF,PBV and DECT(P < 0.0001).No linear correlation was found between MRI perfusion parameters and attenuation values of DECT iodine maps(PBF:r = 0.35,P = 0.15;PBV:r = 0.34,P = 0.16;MTT:r = 0.41,P = 0.08).Visual analysis revealed a moderate correlation between perfusion defects on DECT iodine maps and the parameter maps of DCE-MRI(mean score 3.6,k 0.45).CONCLUSION:There is a moderate visual but not statistically significant correlation between DECT iodine maps and perfusion parameter maps of DCE-MRI.     

双源双能量CT成像评估猪急性心肌缺血再灌注损伤的实验研究

目的 评价双源双能量CT(DECT)成像诊断猪急性心肌缺血再灌注损伤的可行性和准确性.方法 8只猪通过开胸结扎冠状动脉左前降支(LAD)或第一对角支(D1)建立再灌注损伤模型,术后行DECT心肌灌注成像扫描.检查结束后立即处死动物,取出心脏,进行氯化三苯基四氮唑(TTC)染色,分析心肌缺血再灌注损伤范围.以病理结果为参照,测量损伤区、非损伤区的CT值以及损伤区面积.将左心室壁分为17个节段,确定DECT心肌灌注碘图、DECT(140、100和平均加权120 kV)3组图像和大体病理上心肌损伤的节段数.以病理结果为金标准分别评价DECT心肌灌注碘图、3组图像显示心肌损伤的敏感性、特异性和一致性.利用方差检验分析损伤区和非损伤心肌不同管电压条件的CT值、大体病理和DECT 3组图像所测量损伤区重量的差异.结果 8只猪DECT心肌灌注碘图见心尖前壁、心尖间隔灌注稀疏甚至缺损,DECT 3组图像中再灌注损伤区CT值均较正常心肌明显降低.与病理金标准对照,DECT心肌灌注碘图诊断再灌注损伤的敏感性、特异性分别为85.2％ (23/27)、86.2％ (94/109),Kappa值为0.62;DECT3组图像的敏感性、特异性和Kappa值:140 kV组分别为88.9％ (24/27)、92.7％ (101/109),0.76;100 kV组分别为85.2％ (23/27)、89.0％(97/109),0.67;平均加权120 kV组分别为88.9％ (24/27)、91.7％ (100/109),0.74.DECT 3组图像测量损伤心肌重量与大体病理所测值之间差异无统计学意义(F=0.419,P=0.741).结论 DECT心肌灌注成像可用于检测猪急性心肌缺血再灌注损伤,与病理诊断一致性较好.     

基于术前CT影像特征预测胆囊癌淋巴管浸润的研究

目的 评估术前胆囊癌CT影像特征对预测胆囊癌淋巴管浸润（LVI）的价值,构建预测胆囊癌LVI的列线图模型并评价其预测效能。方法 回顾性分析116例接受术前增强CT检查的胆囊癌病人的临床、病理及影像资料。病人按6︰4比例随机分为训练集72例,验证集44例。根据病理结果将病人分为LVI阳性组及LVI阴性组。由2位放射科医生评估训练集及验证集的CT影像特征,包括肿瘤基底浸润胆囊壁范围、影像T分期和N分期、有无胆囊结石。采用独立样本t检验、Mann-Whitney U检验及χ²检验比较2组病人中各项CT征象的差异性,并对训练集采用logistics回归分析筛选独立危险因素。建立列线图预测模型,采用受试者操作特征（ROC）曲线评估预测模型的预测效能并计算相应的曲线下面积（AUC）,绘制校准曲线对列线图预测模型进行验证。采用决策曲线评价其临床净获益。结果 训练集及验证集中,LVI阳性组的CT影像N分期、肿瘤基底浸润胆囊壁范围、T分期均显著高于LVI阴性组（均P<0.05）。多因素分析结果显示影像N分期、T分期、肿瘤基底浸润胆囊壁范围为LVI独立危险因素。建立列线图预测模型,结果显示肿瘤基底浸润范围的得分最高,其次是N分期,再次是T分期。决策曲线分析显示模型的净获益良好,训练集和验证集中CT影像特征预测LVI的ROC曲线的AUC分别为0.828（95%CI：0.721~0.907）、0.752（95%CI：0.599~0.870）,差异无统计学意义（P>0.05）。训练集AUC的截断值为0.521时,模型在训练集中的敏感度、特异度分别为0.629和0.892;验证集AUC的截断值为0.432时,对应的敏感度和特异度分别为0.778和0.654。结论 联合T分期、N分期及肿瘤基底浸润范围建立的列线图预测模型,能够有效预测胆囊癌LVI。     

Quantitative evaluation of non-ischemic dilated cardiomyopathy by late iodine enhancement using rapid kV switching dual-energy computed tomography: A feasibility study

ObjectivesThe aim of this study was to evaluate the feasibility of myocardial iodine density and extracellular volume fraction (ECV) from delayed iodine density images using dual-energy computed tomography (DECT) for differentiation between non-ischemic dilated cardiomyopathy (NIDCM) patients and normal subjects.MethodsForty-six subjects were imaged, including 35 normal subjects and 11 patients with NIDCM. All subjects underwent myocardial delayed enhancement (MDE) imaging on rapid-kVp switching DECT. Global and segmental iodine density and ECV were calculated from MDE images. Histogram analysis was also performed. Receiver-operator characteristic (ROC) analysis was used to determine the cut-off value and diagnostic performances in differentiating NIDCM patients from normal subjects.ResultsGlobal iodine density and ECV were significantly higher in NIDCM compared with normal controls (iodine: 14.19 ± 3.90 vs. 10.69 ± 1.88 in 100 μg/cm³, p = 0.015; ECV: 31.35 ± 2.53% vs. 26.62 ± 2.69%, p < 0.001). In histogram analyses, kurtosis was higher in NIDCM than in controls (0.47 ± 0.46 vs. 1.26 ± 0.88, p < 0.001). On segmental analysis, ECV showed higher values in NIDCM than in controls for all segments. ECV could differentiate between normal myocardium and NIDCM with 91.0% sensitivity and 86.0% specificity at a cut-off of 28.82% (area under the curve of ROC, 0.906). Iodine density could differentiate between normal myocardium and NIDCM with 91% sensitivity and 60% specificity at a cut-off of 11.18 (area under the curve of ROC, 0.812).ConclusionsIodine density and ECV values from DECT may provide indices offering high diagnostic accuracy for discriminating between NIDCM and normal myocardium.     

Myocardial extracellular volume fraction to differentiate healthy from cardiomyopathic myocardium using dual-source dual-energy CT

ObjectiveTo evaluate the feasibility of dual-energy CT (DECT)-based iodine quantification to estimate myocardial extracellular volume (ECV) fraction in patients with and without cardiomyopathy (CM), as well as to assess its ability to distinguish healthy myocardial tissue from cardiomyopathic, with the goal of defining a threshold ECV value for disease detection.MethodsTen subjects free of heart disease and 60 patients with CM (mean age 66.4 ± 9.4; 59 males and 11 females; 40 ischemic and 20 non-ischemic CM) underwent late iodine enhanced DECT imaging. Myocardial iodine maps were obtained using 3-material decomposition. ECV of the left ventricle was estimated from hematocrit levels and the iodine maps using the AHA 16-segment model. Receiver operating characteristic curve analysis was performed, with corresponding area under the curve, along with Youden's index assessment, to establish a threshold for CM detection.ResultsThe median ECV for healthy myocardium, non-ischemic CM, and ischemic CM were 25.4% (22.9–27.3), 38.3% (33.7–43.0), and 36.9% (32.4–41.1), respectively. Healthy myocardium showed significantly lower ECV values compared to ischemic and non-ischemic CM (p < 0.001). From Youden's index analysis, an ECV>29.5% would indicate the presence of CM in the myocardium (sensitivity = 90.3; specificity = 90.3); the AUC for this criterion was 0.950 (p < 0.001).ConclusionThe findings of this study resulted in a statistically significant distinction between healthy myocardium and CM ECVs. This led to the establishment of a promising threshold ECV value that could facilitate the differentiation between healthy and diseased myocardium, and highlights the potential of this DECT methodology to detect cardiomyopathic tissue.     

基于影像学特征对骨质疏松性椎体压缩骨折病人经皮椎体成形术后同椎体再发骨折的预测研究

目的 探讨基于影像学特征对骨质疏松性椎体压缩骨折（OVCF）病人经皮椎体成形术（PVP）后的列线图模型预测术椎椎体再发骨折的价值。方法 回顾性纳入急性OVCF并行PVP后的病人93例。所有病人均行X线及MRI检查,根据椎体再发骨折诊断标准将病人分为再发骨折组（48例）和无再发骨折组（45例）。采用t检验和卡方检验比较2组间临床资料及影像特征的差异,对差异有统计学意义的指标进行多因素Logistic回归分析,获取再发骨折的独立危险因素,采用R软件建立列线图模型并绘制其校准曲线。采用受试者操作特征（ROC）曲线评估模型的预测效能,计算ROC曲线下面积（AUC）。应用校准曲线对列线图模型进行验证。结果 再发骨折组的椎体高度恢复率、延伸至终板的骨折线、椎体内裂隙（IVC）、骨水泥周围积液及骨水泥-终板未接触（NPEC）与无再发骨折组的差异均有统计学意义（均P<0.05）;多因素Logistic回归分析显示延伸至终板的骨折线[优势比（OR）=3.232]、存在IVC(OR=27.117)和NPEC(OR=1.993)及较高的椎体高度恢复率（OR=2.943）为同椎体再发骨折的独立危险因素（...     

CT-based response assessment of advanced gastrointestinal stromal tumor: Dual energy CT provides a more predictive imaging biomarker of clinical benefit than RECIST or Choi criteria

Objectives

Dual-energy CT (DECT) allows quantification of intravenously injected iodinated contrast media in tumors, and therefore may be considered as a surrogate marker for perfusion and tumor vascularity. This study evaluated whether newly developed DECT response criteria allow better correlation with survival than established response criteria.

Methods

Seventeen patients with advanced GIST treated with tyrosine-kinase-inhibitors were assessed by contrast-enhanced DECT 2 and 6 months after beginning of treatment. Response to treatment of 165 tumor lesions was evaluated according to RECIST, Choi criteria and newly developed DECT criteria, defining non-responders as an increase of both tumor size >20% and iodine related attenuation or either a >50% increase of tumor size or iodine related attenuation. All other patients were classified as responders. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan–Meier analysis.

Results

Choi criteria and DECT showed a significantly longer median PFS of patients rated as responders than patients rated as non-responders (9–29 months vs. 2–6 months; p < 0.02) at follow-up. Only DECT analysis at 6 months follow-up allowed a valid prediction of OS.

Conclusion

This study indicates that DECT allows a better prediction of therapeutic benefit in advanced GIST patients treated with tyrosine-kinase-inhibitors than established response criteria. However, the most important predictive biomarker of therapeutic benefit was absence of progression, no matter which response evaluation criteria were applied.     

CT arthrography: in vitro evaluation of single and dual energy for optimization of technique

The purpose of this study was to optimize CT arthrography technique and determine if dual energy CT (DECT) can provide any benefit over single energy CT (SECT). Iodinated contrast attenuation at different concentrations was measured using DECT and SECT at different beam energies (140, 120, and 80 kVp). Dose and noise were measured on phantoms at different tube currents. Three bovine femoral condyles with artificially created cartilage defects were scanned with dose-equivalent protocols. Contrast-to-noise ratio (CNR) between cartilage and iodine was measured, and the appearance of cartilage defects was graded by two readers. DECT scans were post-processed for iodine quantification. The beam energy 80 kVp had the highest iodine signal, 50% greater than DECT, 75% greater than 120 kVp, and 100% greater than 140 kVp. Noise was nearly identical for all techniques when dose was matched. The 80 kVp level had the highest CNR, 25% higher than 120 kVp and DECT, and 33% greater than 140 kVp. The 80 kVp technique was also preferred by both readers. DECT iodine quantification was significantly limited by the post-processing application, noise, and beam hardening. In this in-vitro study, the SECT 80 kVp CT arthrography technique was superior to currently performed 120 and 140 kVP SECT techniques and DECT.