俯卧位CT在经皮肾穿刺中避免邻近器官损伤的辅助作用:附一例报告

正经皮肾镜碎石取石术(percutaneous nephrolithotomy,PCNL)是目前治疗上尿路结石的主要方法。有国外文献报道称其手术并发症发生率为5.3%～10.3%[1-2],国内有报道为6.2%[3]。其中有关脾脏损伤的报道较少见[4-5]。PCNL术前常规的CT检查一般都是采取仰卧位,如果是俯卧位,在术前的CT检查中观察到的仰卧位时肾脏邻近器官与肾脏的相对位置及邻近器官与经皮肾穿刺通道的关     

64层螺旋CT胸部低剂量扫描方案优选的多中心研究

目的 比较自动曝光控制技术(AEC)与管电流恒定技术(CCC)2种不同低剂量MSCT扫描方案对胸部CT图像质量的影响,探讨更加合理的肺低剂量扫描参数方案.方法 采用前瞻性多中心研究方法,研究对象为7所医院就诊的280例行胸部低剂量MSCT检查的受检者,设定管电流(mA)为研究变量,方法一为AEC技术,下设噪声标准差值(SD)为25(A1)及30(A2)各1组,并设定管电流上限为80 mA,下限为10 mA;方法二为CCC技术,下设40 mA(C1)及50 mA(C2)各1组;共4组,采用同一机型64层MSCT行胸部低剂量扪描.2名放射科医师应用双肓法阅片,比较2种不同扫描技术的曝光剂量、SD值,横断面、MPR的图像质量以及体质量指数(BMI)对图像质量的影响.曝光剂量及SD比较行方差分析及t检验;图像质量比较行Mann-Whitney检验;医师对图像诊断一致性检验行Kappa分析.结果 剂量长度乘积(DLP)AEC组较CCC组明显降低[(82.62±40.31)和(110.81±18.21)mGy·cm,F=56.88,P＜0.01].AEC技术中A2组DLP较A1组低[(72.77±36.68)和(92.46±41.61)mGy·cm],差异无统计学意义(t=0.82,P＞0.05).前者SD值在肺窗[(41.50±9.58)和(40.86±7.03)HU]及纵隔窗[(41.19±7.83)和(40.92±9.89)HU]均略高于后者,差异无统计学意义(F肺窗=0.835、1.910,P值均＞0.05).横断面图像质量AEC组肺窗得分除右下肺静脉水平[(4.92±0.25)和(4.93±0.17)分]、[左膈顶上缘水平(4.91±0.27)和(4.93±0.22)分]较CCC组略低外,AEC组得分均较CCC组略高[头臂静脉上缘(4.49±0.56)和(4.38±0.64)分;主动脉弓上缘(4.86±0.23)和(4.81±0.32)分;右肺上叶支气管开口(4.87±0.27)和(4.84±0.22)分;右肺中叶支气管开口(4.90±0.25)和(4.88±0.21)分],差异无统计学意义(F=0.076～1.748,P值均＞0.05);纵隔窗得分除头臂静脉上缘水平AEC组较CCC组高[(2.57±0.77)和(2.46±0.59)分],且差异有统计学意义(F=8.459,P=0.047)外,余各层面AEC组得分均较CCC组略低[(主动脉弓上缘(3.36±0.63)和(3.45±0.60)分;右肺上叶支气管开口(3.94±0.56)和(3.95±0.51)分;右肺中叶支气管开口(3.80±0.58)和(3.87±0.50)分;右下肺静脉(3.72±0.56)和(3.78±0.53)分;左膈顶上方(3.58±0.63)和(3.68 ±0.56)分],但差异均无统计学意义(F=0.083～3.380,P值均＞0.05).MPR图像质量肺窗及纵隔窗观察均略好于CCC组(Z肺窗=-2.358,Z纵隔窗=-1.330,P值均＞0.05).偏瘦、正常或偏重人群组,A1组肺窗及纵隔窗图像质量均优于A2组,差异无统计学意义(偏瘦:Z肺窗=0.000、Z纵隔窗=0.000;正常:Z肺窗=-0.062、Z纵隔窗=-0.746;偏重:Z肺窗=-1.177、Z纵隔窗=-1.715;P值均＞0.05),但在偏重人群纵隔窗图像质量A1组更好于A2组(Z=-1.715,P=0.144).结论 AEC组总曝光剂量明显低于CCC组,而AEC组的图像质量及SD值无论在肺窗或纵隔窗均与CCC组无明显差异,故建议在胸部低剂量筛查方案选择中应用AEC技术,对偏胖者宜采用SD=25方案,对正常及偏瘦者宜采用SD=30方案.

Abstract：

Objective To compare the image quality of chest low dose CT (LDCT) using automatic exposure control (AEC) and constant current control (CCC) and explore a more reasonable scanning protocol. Methods Two hundred and eighty participants were examined with 64 CT scanner at 7 centers in China. All were divided into 4 groups. Two groups underwent LDCT using AEC with standard deviation set at 25 (A1) and 30 (A2) respectively and the tube current ranged from 10 mA to 80 mA. The other two groups underwent LDCT using CCC with tube current set at 40 mA (C1) and 50 mA (C2) respectively. The axial and MPR images were evaluated by two radiologists who were blinded to the scanning protocols.The radiation dose, noise and the image quality of the 4 groups were compared and analyzed statistically.Differences of radiation dose and noise among groups were determined with variance analysis and t test,image quality with Mann-Whitney test and the consistency of diagnosis with Kappa test. Results There was a significant lower DLP in AEC group than in CCC group [(82.62±40.31)vs ( 110.81±18.21) mGy·cm (F =56. 88 ,P ＜ 0. 01 )], whereas no significant difference was observed between group A2 and group A1 0. 05]. The noisy of AEC group was higher than that of CCC group both on lung window(41.50±9.58 vs 40.86±7.03) and mediastinum window (41.19±7.83 vs 40.92±9.89), but there was no significant difference( Flung =0.835, P=0.476, Fmediastinum =1.910, P=0.128).The quality score of axial image in AEC group was higher than that in CCC group (superior margin of the brachiocephalic vein level: 4.49±0.56 vs4.38±0.64,superior margin of the aortic arch: 4.86±0.23 vs 4.81±0.32,the right superior lobar bronchus Level:4.87±0.27 vs 4. 84 ± 0. 22, the right middle lobar bronchus Level: 4.90±0.25 vs 4.88±0.21) except on the right inferior pulmonary vein level(4. 92 ±0. 25 vs 4. 93 ±0. 17) and superior margin of the left diaphragmatic dome level (4. 91±0.27 vs 4.93±0.22) on lung window, but no significant differences (F=0.076-1.748, P＞0.05) were observed. A significant higher score in AEC group was observed on mediastinum window compared with CCC group on superior margin of brachiocephalic vein level (2.57±0.77 vs 2. 46 ± 0. 59, F = 8. 459, P ＜ 0. 05 ), however, the score of AEC group was lower than that of CCC group on other levels without significant differences (superior margin of the aortic arch:3.36 ±0. 63 vs 3.45 ±0. 60,the right superior lobar bronchus level: 3.94 ±0. 56 vs 3. 95 ±0. 51 ,the right middle lobar bronchus Level: 3.80 ±0. 58 vs 3. 87 ±0. 50,the right inferior pulmonary vein level: 3.72 ±0. 56 vs 3.78 ±0. 53, superior margin of the left diaphragmatic dome level: 3.58 ± 0.63 vs 3.68±0.56,F=0.083-3.380,P ＞ 0.05 ). The MPR image quality of AEC group was better than that of CCC group both on lung window and mediastinum window (Zlung =-2.258, Zmedlastinum=-1.330, P＞0.05). For all participants including the underweighted group, the normal group and the overweighted group, the image quality of A1 group was better than that of A2 group without significant differences (the underweighted group: Zlung=0.000, P=1.000, Zmedastinum= 0.000, P=1.000;the normal group: Zlung =-0.062, P=0.950, Zmediastinum =-0.746, P = 0.456; the overweighted group: Zlung = - 1.177, P = 0.239,Zmediastinum =-1.715, P=0.144) both on lung and mediastinum windows, and for the higher BMI participants, a better image quality was obtained in A1 group than in A2 group on the mediastinum window (Z = -1. 715, P = 0. 144). Conclusions The total radiation exposure dose of AEC group is significantly lower than that of CCC group, but no statistical significant differences are observed between both groups in image quality and noise level. The AEC technique is highly recommended in thoracic LDCT scan for screening program, and the SD25 ( SD value = 25) scan protocol is suggested for higher BMI population while the SD30 (SD value = 30) scan protocol for lower BMI population.     

辛伐他汀局部注射对大鼠骨质疏松性骨折愈合的影响

目的： 研究辛伐他汀局部注射对去势大鼠骨折愈合的影响。方法: 2月龄雌性SD大鼠采用去势方法模拟人绝经后骨质疏松症,模型成立后进一步建立胫骨骨折髓内钉内固定模型,实验组于骨折端皮下注射辛伐他汀(10 mg·kg^-1·d^-1,5 d),另一组仅注射无辛伐他汀的溶剂作为空白对照组。骨折后1、2、4周取标本,通过X片、生物力学、组织病理学以及组织形态计量学等方法评价两组骨折愈合质量。结果: 与空白对照组相比,实验组骨痂横截面积在骨折后1周、2周分别增加21.3% (P<0.05) 和21.5% (P<0.05);骨痂最大载荷在骨折后2周、4周分别增加57.5% (P<0.05) 和31.4% (P<0.05);组织学显示实验组新生编织骨较对照组多且排列致密;组织形态计量学测量结果表明辛伐他汀可明显增加矿化宽度(MLW)、矿化容积(MLV) 以及矿化率(MAR)。结论: 局部应用辛伐他汀可促进去势大鼠骨折愈合。     

肺腺癌磨玻璃结节影像特征与EGFR基因突变的相关性分析

目的 磨玻璃结节(ground glass nodule,GGN)的疾病谱包括良性及恶性的病变,有关于GGN的自然生长史目前尚未完全清楚,本研究回顾性定量分析高分辨CT(high-resolution computed tomography,HRCT)表现为纯磨玻璃结节(pure ground glass nodule,pGGN)和实性成分＜5 mm部分实性结节的肺腺癌表皮生长因子受体(epidermal growthfactor receptor,EGFR)基因突变的特点及其与影像表现的关系.方法 2012-04-23 2015 10 30经中国医学科学院肿瘤医院病理确诊为肺腺癌的GGN患者79例.通过测序法检测EGFR基因突变.将患者分为EGFR突变型组及野生型组,分别记录各组患者性别、年龄、病灶位置、大小、相对CT值及薄层CT征象(分叶、毛刺、空泡征、空气支气管征、胸膜牵拉及凹陷征),观察两组GGN影像特征与EGFR基因突变的关系,并进行统计学分析.结果 79例GGN患者中,EGFR突变组41例(51.9％),EGFR野生型组38例(48.1％);EGFR突变组与野生型组之间患者年龄、性别、GGN的位置、分叶、毛刺、空泡及CT空气支气管征、相对CT值差异均无统计学意义,均P＞0.05.突变型组GGN胸膜牵拉或凹陷征发生率高于野生型组,P=0.037.EGFR突变型组的GGN大小、体积及质量均显著高于野生型组(P值分别＜0.001、0.002和0.001).GGN大小、体积、质量预测EGFR突变的最佳临界值分别为10.45 mm、540.6 mm3和0.255 g.结论 在pGGN和实性成分＜5 mm部分实性结节肺腺癌中,HRCT影像特征对于辅助预测EGFR基因突变状态具有一定价值.     

老年股骨转子间骨折手术治疗若干问题探讨

股骨转子间骨折指发生在股骨颈关节囊外至小转子下缘之间的骨折^[1]。除部分年轻患者为高能量损伤引起外,绝大部分的转子间骨折为高龄患者的脆性骨折,该部位主要有松质骨构成,是老年性骨质疏松的好发部位;同时其近端和远端比邻骨密度相对较高的股骨颈和转子下区,是股骨近端骨质相对薄弱区域,重力在该部位产生内翻力矩,应力的相对集中也是转子间好发骨折的原因之一。此外,老年人因视觉、听觉功能下降,神经系统及运动系统综合反应能力降低,外伤概率明显增高,这也是老年人易发生转子间骨折的重要原因。     

腹膜后周围神经源性肿瘤的超声诊断

目的 分析腹膜后周围神经源性肿瘤的超声诊断特点,提高超声定性诊断水平。方法 经手术病理证实的腹膜后周围神经源性肿瘤26例。结果 腹膜后良性周围神经源性肿瘤多位于脊柱旁、肾周;形态规则,边缘清晰,有包膜回声;内部以低回声为主,可有囊变,后方回声增高;实质回声欠均匀。超声提示良性神经源性肿瘤19例,诊断总符合率90.5%(19/21),其中神经鞘瘤100%（14/14）,神经纤维瘤71.4%(5/7)。腹膜后MPNST形态不规则,边缘不清晰,无包膜;瘤体巨大,内部回声不均匀,以低回声多见,后方回声增高,可有囊变,超声诊断恶性肿瘤5例,均未提示其来源,结论 腹膜后良性周围神经源性肿瘤超声诊断有一定特异性,定性准确率高,腹膜后MPNST,超声检查仅可判断良恶性,而不能进一步提示其来源。     

Early period of fracture healing in ovariectomized rats

Objective. To evaluate the effect of osteoporosis on fracture healing through observing the hlstomorphological changes, bone mineral density of callus and expression and distribution of transforming growth factor beta 1 (TGF-β1 ), basic fibroblast growth factor (bFGF)and bone morphogenetic protein.2 (BMP-2) in ovariectomized rats. Methods. Sixty female Sprague-Dawley rats ( aged 12 weeks and weighing 235 g on average ) were randomly divided into an ovariectomized (OVX) group (n =30) anda sham-operated (SO) group ( n = 30). Ovariectomy was performed in the OVX rats and same incision was made in the SO rats. Three months later, fracture of femoral shaft was made on all the rats. Then they were killed at different time points. Callus formation was observed with histological and imethods. Results: A reduction in callus and bone mineral density in the healing femur and a decrease of osteoblasts expressing TGF-β1 near the bone trabecula were observed in the OVX rats 3-4 weeks after fracture.Histomorphological analysis revealed a higher content of soft callus in the OVX rats than that in the SO rats.Immunohistochemistry results showed that no remarkable difference in expression and distribution of BMP-2 and bFGF between the OVX and SO groups was found. Conclusions: Osteoporosis influences the quantity and quality of callus during the early period of fracture healing. The effect of osteoporosis on fracture healing has no relationship with the expression of BMP-2 or bFGF. The decreased expression of TGF-I31 in osteoblasts may cause a decrease in quality of facture healing after osteoporosis.     

多层螺旋CT重建参数对头颈部肿瘤MPR图像质量的影响

目的　分析多层螺旋CT(MSCT)重建及重组参数对头颈部肿瘤MPR图像质量的影响 ,以便选择最佳的参数组合。资料与方法　使用GELightspeedUltra 8层螺旋CT扫描机对 6 7例头颈部肿瘤患者进行扫描。分为两部分 ,第一部分 2 8例 ,分别对原始数据进行 1.2 5mm、2 .5mm层厚的轴面重建 ,重叠率均为 5 0 %。图像重组时 ,分别采用层厚 1mm、2mm、3mm和 5mm。第二部分 39例 ,分别采用 0 %、2 5 %、5 0 %和 75 %的重叠率和 1.2 5mm层厚进行轴面重建 ,然后采用 1mm层厚进行图像重组。应用双盲法评价各组图像质量 ,并进行统计学处理。结果　第一部分 ,在软组织、骨质和伪影方面组内差异有极显著性 (P <0 .0 1) ,1.2 5mm层厚轴面重建的各组MPR图像中 ,1mm层厚组对软组织和骨质的显示好于其他各组 (P <0 .0 1)。第二部分 ,在软组织、病变、骨质和伪影方面组内差异有极显著性 (P <0 .0 1) ;在软组织和病变方面 ,5 0 %与 75 %重叠率图像质量最佳 ,两者差异无显著性 (P >0 .0 5 ) ;在骨质方面 75 %重叠率组图像质量高于 5 0 %组 (P <0 .0 5 ) ;在伪影方面 ,5 0 %重叠率组好于 75 %组 (P <0 .0 1)。结论　头颈部肿瘤MSCT图像后处理采用 1.2 5mm层厚、5 0 %重叠率进行轴面重建后 ,用 1mm层厚的MPR图像能很好地显示软组织、病变     

经尿道1.9μm铥激光膀胱肿瘤切除术的疗效与安全性分析

目的 以经尿道等离子汽化膀胱肿瘤切除术(transurethral plasma kinetic resection of bladder tumor, TUPKBt)为对照,分析经尿道1.9 μm铥激光膀胱肿瘤切除术(thulium laser resection of bladder tumor, TmLRBt)的疗效与安全性.方法 比较72例分别行TUPKBt及经尿道1.9 μm TmLRBt患者术中、术后的相关指标.所有患者随机分为TUPKBt组(n=35)和TmLRBt组(n=37).结果 两组患者的性别、年龄、肿瘤特点比较差异无统计学意义.TUPKBt组发生闭孔神经反射4例,TmLRBt组未发生闭孔神经反射.TUPKBt组需要进行膀胱冲洗患者比例为45.7%(16/35)、留置尿管时间(3.5±0.8)d. TmLRBt 组需要膀胱冲洗患者比例为18.9%(7/37)、留置尿管时间(2.2±0.7)d.术后平均随访18(4~25)个月.两组均无复发.结论 TmLRBt治疗膀胱安全有效,手术并发症及术后恢复时间优于TUPKBt.     

肺硬化性血管瘤的影像学与病理学对照研究

目的回顾性分析肺硬化性血管瘤(PSH)的影像学表现，并与病理学对照，旨在提高对PSH影像表现的认识。方法1976年1月至2002年12月由手术及病理证实的PSH共45例，其中男3例，女42例(93．3％)，年龄18～67岁，中位年龄49岁。无症状由体检发现19例(42．2％)。影像学资料(包括胸部正、侧位X线片和CX)完整的PSH共20例。平扫7例，直接增强扫描13例。将影像表现与病理对照。结果典型X线片表现为圆形、卵圆形边界清楚的肿物或结节，无分叶及毛刺。CT平扫7例，病变密度与肌肉密度相仿。直接增强扫描13例，9例为均匀强化(其中4例增强早期呈不均匀强化，延时后均匀强化)，4例呈不均匀强化，强化程度略高于或明显高于肌肉密度，强化的最大CT值为135HU。13例增强CT的病变中，强化程度高于或明显高于肌肉的11例，全部含有较多的血管瘤成分。含有较大面积低密度区的1例，组织学显示有囊变。影像检查见有钙化的5例均与病理学所见吻合。结论有助于PSH影像诊断的指标为：(1)40-60岁的女性患者；(2)胸片上表现为圆形、卵圆形边界清楚的肿物或结节；(3)CT平扫密度均匀，有时有小低密度区和粗大点状钙化，偶尔可见囊性变；(4)CT增强后有中度至明显强化。对于增强早期呈明显不均匀强化的圆形、卵圆形边界清楚的肿物或结节，应行延时扫描。