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1.
目的探讨双源CT低kV和CARE Dose 4D管电流调节技术对降低主动脉CT血管成像(CTA)的辐射剂量的价值及其对图像质量的影响。资料与方法对临床拟诊主动脉夹层的53例患者行双源CT主动脉成像检查。并按数字表法将患者随机分为3组:A组:17例。扫描管电压为120 kV;B组:18例。扫描管电压为120 kV和CARE Dose 4D技术;C组:18例。扫描管电压为100 kV和CARE Dose 4D技术;3组其他扫描参数和重组参数均相同。测量气管分叉层面和肝门层面主动脉的CT强化值及图像噪声(SD),并由两名有经验的医师对3组图像质量进行评价。比较A组和B组、B组和C组平均容积CT剂量指数(CTDIvol),剂量长度乘积(DLP),有效剂量(ED),SD,信噪比(SNR),对比噪声比(CNR)和扫描长度。结果 A、B、C 3组图像质量评分依次为2.94±0.24、2.89±0.32、2.94±0.23。A、B、C 3组CTDIvol分别为(7.2±1.8)mGy、(6.1±1.4)mGy、(3.7±1.0)mGy;ED分别为(6.0±0.4)mSv、(5.0±1.0)mSv、(3.2±0.9)mSv;S...  相似文献   

2.
_目的:探讨自动管电流调节(CARE Dose 4D)联合智能最佳 kV(CARE kV)技术在眼眶 CT 检查中的临床应用价值。方法:将行眼眶 CT 检查的70例患者分为两组,A 组(35例)采用 CARE Dose 4D 扫描技术,B 组(35例)采用CARE kV 联合 CARE Dose 4D 扫描技术。比较 A、B 两组图像质量(平均 CT 值、噪声 SD、SNR、CNR、图像质量主观评分)、患者所接受的辐射剂量及病变检出率。结果:A、B 两组辐射剂量差异有统计学意义(P<0.05),B 组[(0.59±1.55)mSv]较 A 组[(0.71±1.84)mSv]ED 较少约15.9%。两组平均 CT 值、噪声 SD、SNR、CNR、图像质量评分及病变检出率差异均无统计学意义(P>0.05)。结论:联合 CARE kV 与 CARE Dose 4D 技术行眼眶 CT 扫描,在保证图像质量的同时,可有效降低辐射剂量。  相似文献   

3.
目的 探讨CT低剂量联合迭代算法在输尿管结石诊断中的应用价值.方法 90例输尿管结石患者在首次检查均应用常规剂量扫描(120 kV,400 mAs),采用滤波反投影算法(FBP)薄层重组,保守治疗后结石未排出.复查CT应用低剂量扫描随机分为3组(A组:120 kV,200 mAs;B组:120 kV,150 mAs;C组:120 kV,100 mAs)后分别行6级迭代算法薄层重组.由2名放射医师采用双盲法读片并对图像质量做主观评分,记录CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP),计算辐射有效剂量(ED);测量图像的客观噪声值,计算信噪比,测量结石CT值及最大长径,记录结石检出数.结果 常规组:CTDIvol(23.51±0.79) mGy,DLP(1166.38±52.78)mGy·cm,ED(17.50±0.79)mSv;A组:CTDIvol(11.78±0.38) mGy,DLP(584.68±25.47) mGy· cm,ED(8.77±0.38) mSv;B组:CTDIvol(8.34±0.13)mGy,DLP(462.87±24.76) mGy· em,ED(6.94±0.37)mSv;C组:CTDIvol(5.47±0.21) mGy,DLP(268.20±19.03)mGy·cm,ED(4.02±0.29) mSv;各组低剂量迭代算法重组的iDose l ~6图像结石检出数、结石CT值及大小与常规剂量比较差异无统计学意义(P>0.05);A组低剂量迭代算法重组的iDose4图像噪声(SD)、信噪比(SNR)及iDose 4—6图像质量主观评分与常规剂量比较差异无统计学意义(P>0.05);B组低剂量迭代算法重建的iDose6图像噪声、信噪比及图像质量主观评分与常规剂量比较差异无统计学意义(P>0.05);C组低剂量迭代算法重建的iDose l~6各组图像噪声、信噪比及图像质量主观评分与常规剂量比较差异有统计学意义(P<0.05).结论 CT低剂量扫描联合迭代算法诊断输尿管结石是可行的,可以在不影响图像质量的前提下明显减低辐射剂量.管电压120 kV情况下,在iDose6水平管电流150mAs为最低临界扫描参数.  相似文献   

4.
目的 :基于离体头颅标本牙齿CT扫描探讨管电流自动调节(CARE Dose 4D)技术降低辐射剂量的可行性。方法 :对10具防腐固定离体头颅标本牙齿分别行A、B组方案扫描。A组采用常规扫描(100 k V/150 m As),B组行CARE Dose 4D扫描,其余扫描参数同A组。比较2组的辐射剂量及图像的平均CT值、噪声、SNR、对比噪声比(CNR)、主观评分等。结果:2组辐射剂量[容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(ED)]采用配对样本t检验,差异均有统计学意义(均P0.05);与A组比较,B组有效剂量降低15.26%。2组图像的平均CT值、噪声、SNR、CNR及主观评分比较差异均无统计学意义(均P0.05)。结论:基于离体头颅标本牙齿CT扫描,运用CARE Dose 4D技术可降低扫描辐射剂量、保障图像质量,值得临床推广运用。  相似文献   

5.
目的:探讨多层螺旋 CT 低剂量扫描技术在甲状腺增强扫描中的临床应用价值。方法80例患者随机分为4组(每组各20例),4组分别为:A 组,120 kV、180 mA;B 组,120 kV、100 mA;C 组,100 kV、180 mA;D 组,100 kV、100 mA。主观评价图像质量并评分,统计甲状腺 CT 值、图像背景噪声(N)、图像信噪比(SNR)、CT 剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED)并进行对比分析。结果4组图像主观评分为3.90±0.31、3.75±0.44、3.70±0.47、3.60±0.60,SNR 为26.34±3.13、25.08±1.87、25.86±2.38、24.87±2.20,四者无统计学差异(P >0.05);甲状腺 CT 值为(168.55±13.39)HU、(170.70±11.34)HU、(185.20±22.35)HU、(190.55±21.38)HU,N 为(6.48±0.84)HU、(6.83±0.45)HU、(7.19±0.86)HU、(7.66±1.01)HU, CTDIvol 为(10.95±0.00)mGy、(6.08±0.00)mGy、(6.59±0.00)mGy、(3.66±0.00)mGy,DLP 为(145.67±8.79)mGy·cm、(84.58±4.94)mGy·cm、(89.86±3.26)mGy·cm、(50.20±1.89)mGy·cm,ED 为(0.73±0.04)mSv、(0.42±0.03)mSv、(0.45±0.03)mSv、(0.25±0.01)mSv,四者有统计学差异(P <0.05)。结论多层螺旋 CT 低剂量扫描技术既能保证图像质量又能有效降低甲状腺增强 CT 检查的辐射剂量。  相似文献   

6.
目的探讨自动管电压技术在腰椎外伤CT检查中降低辐射剂量的应用价值。方法对80例腰椎外伤患者根据就诊顺序随机分为2组:A组43例、B组37例,A组采用自动管电压(CARE kV),参考管电压100kV,CARE Dose 4D自动mAs技术,螺距0.8,旋转时间1.0s进行扫描;B组采用固定管电压120kV进行扫描,其它扫描条件与A组相同。记录每次扫描的放射容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(ED)。对图像进行主观质量评分及测量客观图像噪声评估。结果 A、B两组有效剂量分别为(2.3±1.2)mSv、(3.6±1.5)mSv,A组与B组比较,平均有效剂量(ED)降低了36.1%;主观图像评分:骨窗A组和B组分别为(4.63±0.05)和(4.56±0.08);软组织窗分别为(4.71±0.06)和(4.66±0.13),两者差异没有统计学意义(P0.05);客观图像质量评估:骨窗A、B两组SNR分别为(2.3±0.6)、(2.5±0.7);软组织窗A、B两组SNR分别为(5.7±1.4)、(6.1±0.9),两组间差异无统计学意义(P0.05)。结论自动管电压技术在腰椎外伤CT检查中可以减少辐射剂量,图像质量能满足腰椎外伤的诊断要求,都能对腰椎外伤做出明确诊断。  相似文献   

7.
目的:对比分析双源CT Flash扫描技术在新型冠状病毒肺炎(简称新冠肺炎)重症患者检查中的应用价值。方法:选择在我院行双源CT检查的100例新冠肺炎重症患者,分为研究组和对照组各50例,研究组采用Flash扫描技术,对照对采用常规剂量扫描技术,对比2组的检查时间、容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED),并比较2组图像的SNR及图像质量优良率。结果:研究组平均检查时间为(0.84±0.14)s,对照组(3.65±0.89)s,差异有统计学意义(P0.01)。研究组CTDIvol、DLP、ED平均值分别为(2.97±0.55)mGy、(106.33±22.63)mGy·cm、(1.49±0.32)mSv,对照组分别为(9.39±4.82)mGy、(290.52±64.28)mGy·cm、(4.07±0.91)mGy,2组差异均有统计学意义(均P0.01)。研究组3处测量点的SNR与对照组比较,差异均无统计学意义(均P 0.05)。研究组图像质量优良率为100.0%,高于对照组的92.0%,差异有统计学意义(P0.05)。结论:对新冠肺炎重症患者采用双源CT Flash扫描技术,可明显缩短检查时间,有效降低辐射剂量水平,且提高图像质量,值得临床推广使用。  相似文献   

8.
目的:探讨CARE技术即自动综合选择管电压(CAREkV)和四维实时剂量调节CAREDose4D技术对冠脉CTA辐射剂量和图像质量的影响。方法将78例患者随机分成两组,采用西门子64排128层DefinitionAS螺旋CT机行回顾性心电门控螺旋扫描。A组41例,由CAREkV选择输出管电压;B组37例,管电压人为设定120kVp。两组均采用CAREDose4D技术,其他扫描参数两组相同。应用t检验比较两组CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED)、图像质量评分、信噪比(SNR)和对比噪声比(CNR),P<0.05认为有统计学差异。结果A和B两组CTDIvol分别为(17.15±10.87)mGy和(29.97±7.80)mGy;DLP分别为(261.43±176.49)mGy×cm和(469.61±119.66)mGy×cm;ED分别为(3.62±2.98)mSv和(6.58±2.03)mSv,两组间CTDIvol、DLP和ED值差异有统计学意义(P<0.05),且A组ED降低44.98%。A和B两组图像质量评分分别为(3.58±0.27)和(3.63±0.31),差异无统计学意义(P>0.05);主动脉根部管腔的SNR分别为(18.14±4.27)和(17.96±3.37),差异无统计学意义(P>0.05);A组RCA和LM近端管腔的CNR分别为(23.07±8.89)和(27.26±9.57),B组分别为(17.23±7.35)和(21.27±8.43),差异有统计学意义(P<0.05),A组CNR大于B组。结论应用于冠状动脉造影的CARE技术,在保证图像质量的同时,可降低受检者44.98%的有效辐射剂量,具有临床意义。  相似文献   

9.
目的 探讨头颈部CT扫描中,不同扫描模式对辐射剂量和影像质量的影响程度。方法 利用头颈部仿真模体和双源CT,分别使用固定扫描条件120 kV和200 mAs,以及自动管电流调制技术(CARE Dose 4D)、自动管电压调制技术(CARE kV)和部分角度扫描模式(X-CARE)的组合进行成像,分别为120 kV+200 mAs、120 kV+200 mAs+X-CARE、CARE Dose 4D+120 kV、CARE Dose 4D+120 kV+X-CARE、CARE Dose 4D+CARE kV、CARE Dose 4D+CARE kV+X-CARE 6种扫描模式。每次扫描均使用两片热释光剂量片(TLD)分别测量眼晶状体和甲状腺的剂量,两片TLD所测数值取均值。记录以上各种扫描时的容积CT剂量指数(CTDIvol)和剂量长度乘积(DLP),测量眼晶状体层面和甲状腺层面影像的对比度噪声比(CNR)。结果 120 kV+200 mAs扫描时,眼晶状体和甲状腺的器官剂量分别为19.8和26.0 mGy,使用120 kV+200 mAs+X-CARE可降低剂量至13.3和22.2 mGy;与CARE Dose 4D+120 kV相比,CARE Dose 4D+CARE kV可使CTDIvol由13.1降至10.1 mGy,眼晶状体剂量和甲状腺剂量由20.8和23.7 mGy分别降至16.6和19.9 mGy,而使用CARE Dose 4D+CARE kV+X-CARE时,器官剂量又进一步分别降至6.3和11.0 mGy,但影像质量显著降低;与CARE Dose 4D+120 kV相比,使用CARE Dose 4D+120 kV+X-CARE,眼晶状体和甲状腺剂量分别由20.8和23.7 mGy降至9.6和15.1 mGy,同时CTDIvol由13.1 mGy降至9.3 mGy。使用CARE Dose 4D+CARE kV+X-CARE时,CTDIvol和器官剂量降至最低,但头颅和颈部CNR也降至最低。结论 颅脑扫描时CARE Dose 4D+120 kV+X-CARE模式、颈部扫描时CARE Dose 4D+CARE kV模式在保持影像质量较好的同时可有效降低辐射剂量。当对影像质量要求不高时可选用CARE Dose 4D+CARE kV+X-CARE模式,从而显著降低辐射剂量。  相似文献   

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目的 探讨双源CT肺动脉成像双能量扫描与普通扫描(单能量扫描)对图像质量及辐射剂量的影响.方法 临床怀疑肺栓塞并行炫速双源CT肺动脉成像单、双能量扫描患者各61例,按扫描方式不同分为A、B2组,A组为双能量扫描(80/Sn140 kV),B组为普通扫描(Care kV选择输出管电压).对2组图像进行图像质量评分及测量2组肺动脉CT值、空气标准差(背景噪声)并计算信噪比(SNR),同时对2组图像的辐射剂量进行对比分析,以P<0.05为具有统计学意义.结果 2组图像质量主观评分2名观察者间一致性较好,Kappa分别为0.705、0.827,2组图像质量评分差异无统计学意义(P>0.05);A组右下肺动脉CT值高于B组,差异有统计学意义(P<0.05),其余肺动脉的CT值差异均无统计学意义(P>0.05);A组图像噪声稍高于B组,SNR稍低于B组,差异无统计学意义(P>0.05);A、B2组CT剂量指数(CTDIvol)、剂量长度乘积(DLP)有效剂量(ED)分别为(6.13± 1.09)mGy和(12.41±3.42) mGy、(172.49士41.35)mGy· cm和(332.16±115.65) mGy.cm、(2.41±0.58) mSv和(4.65±1.62) mSv,差异具有统计学意义(P=0.000),A组CTDIvol、DLP、ED较B组分别减少50.60%、48.07%、48.17%.结论 双源CT肺动脉成像双能量扫描(80/Sn140 kV)的图像质量与单能量扫描相近,X线辐射剂量较单能量扫描明显降低.  相似文献   

11.
The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.  相似文献   

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Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

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Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

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Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas (CCF) and their complications such as pseudoaneurysms. Methods: Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% (4/22). A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% (8/22). Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.  相似文献   

18.
In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

19.
Objective To evaluate the preliminaily clinical efficacy and retrievability of a retrievable hinged covered metallic stent in the treatment of the bronchial stump fistula (BSF). Methods Between April 2003 and March 2005, 8 patients with bronchial stump fistula after pneumonectomy or lobectomy were treated with two types (A and B) of retrievable hinged covered metallic stents. Type A stent was placed in 6 patients and type B in 2 under fluoroscopic guidance. The stent was removed with a retrieval set when BSF was healed or complications occurred. Results Stent placement in the bronchial tree was technically successful in all patients, without procedure-related complications. Immediate closure of the BSF was achieved in all patients after the procedure. Stents were removed from all patients but one. Removal of the stents was difficult in two patients due to tissue hyperplasia. Patients were followed up for 6 - 21 months. Placement of the stents remained stable in all patients except one due to severe cough. Permanent closure of BSF was achieved in 7 (87.5%) of 8 patients. Conclusion Use of a retrievable hinged covered expandable metallic stent is a simple, safe, and effective procedure for closure of the BSF. Retrieval of the stent seems to be feasible. (J Intervent Radiol, 2007, 16: 253-257)  相似文献   

20.
The purpose of this study was twofold: (a) to investigate the prevalence of hip and groin pain in sub‐elite male adult football in Denmark and (b) to explore the association between prevalence and duration of hip and groin pain in the previous season with the Copenhagen Hip and Groin Outcome Score (HAGOS) in the beginning of the new season. In total 695 respondents from 40 teams (Division 1–4) were included. Players completed in the beginning of the new season (July–Sept 2011) a self‐reported paper questionnaire on hip and/or groin pain during the previous season and HAGOS. In total 49% (95% CI: 45–52%) reported hip and/or groin pain during the previous season. Of these, 31% (95% CI: 26–36%) reported pain for >6 weeks. Players with the longest duration of pain during the previous season had the lowest HAGOS scores, when assessed at the beginning of the new season, P < 0.001. This study documents that half of sub‐elite male adult football players report pain in the hip and/or groin during a football season. The football players with the longest duration of pain in previous season displayed the lowest HAGOS scores in the beginning of the new season.  相似文献   

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