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ObjectiveThe detection of abnormal findings on computed tomography (CT) scans of tuberculosis contacts combined with normal plain radiographs contributes to the early detection of tuberculosis. However, the benefit of the early detection of abnormalities for the prevention of active tuberculosis during follow-up requires evaluation.MethodWe conducted retrospective comparison of the existence of CT scans of tuberculosis contacts without findings of active tuberculosis on plain radiographs at a hospital in Japan. Results: Among 243 contacts without CT scans, five developed tuberculosis during follow-up. Among 229 contacts with CT scans, 24 were judged as targets of multi-drug therapy since their CT findings were suggestive of active tuberculosis at the time of the CT screening. Among 205 contacts judged as having latent tuberculous infection with CT screening, three developed tuberculosis diseases during follow-up. Conclusion: CT scans detected abnormal findings among contacts without abnormalities of plain radiographs but there were some contacts that developed tuberculosis diseases among those with contact investigation including CT scan. The value of CT is equivocal considering the balance of true treatment, overtreatment and harm of radiation.  相似文献   
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PurposeAttempts by magnetic resonance (MR) manufacturers to help imaging centres improve patient throughput has led to the development of more automated acquisition. This software is capable of customizing individual scan alignment; potentially improving imaging efficiency and standardizing protocols. However, substantial investments are required to introduce such systems, potentially deterring their widespread application. This study assessed the implementation costs and reduction in examination durations for automated knee MR imaging (MRI) software.Materials and MethodsResearch activities were performed at a community-based academic centre on a 3-Tesla (3-T) system using Siemens' Day Optimizing Throughput (Dot) knee software. Examination acquisition times were extracted from the system before and after software implementation. Fiscal year 2012/13 finances were used to determine the average hourly cost of MRI utilization. Costs associated with automated software implementation were also calculated. Finally, the number of knee scans required to achieve a positive return on investment using the software was established.Results and DiscussionThe mean (standard deviation, sample size) pre- and post-Dot software scan times were 23.20 (4.18, n = 266) and 21.94 (4.51, n = 59) minutes, respectively, for a routine knee scan and 11.88 (1.60, n = 74) and 11.24 (1.51, n = 27) minutes, respectively, for a fast knee scan. The overall weighted average resulted in a 64-second time savings per automated knee examination. This negligible time savings would be extremely difficult to make use of clinically. Dot simplified 29 unique knee protocols to two, improving the consistency of knee examinations. Current Dot software is not compatible with all patients and therefore has limitations that are a concern among MR technologists.ConclusionAdoption of automated knee systems could assist in standardizing protocols; however, the cost of implementation and difficulty in modifying patient scheduling to reflect the minimal time savings would make a financial return unlikely to occur at small- and medium-sized institutions.  相似文献   
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BackgroundManagement of inflammatory bowel diseases (IBD) in the emergency department is often suboptimal.AimsTo develop a national consensus checklist of indicators to facilitate decision-making in emergency departments concerning hospitalisation and referral for abdominopelvic computed tomography (CT).MethodsA Delphi survey was used to obtain consensus on a checklist of clinical and biological variables. 119 healthcare professionals experienced in treating IBD were invited to participate. Panellists were provided with a literature survey and invited to agree or disagree with items on a prototype checklist. Two successive rounds of voting were organised.ResultsThe prototype checklist included fifteen clinical or laboratory indicators for hospitalisation or CT. Four indicators were not retained in the Delphi process and four additional indicators added. The final indicators retained were: abdominal signs/symptoms of disease exacerbation, intravenous morphine titration, fever, vomiting, dehydration, recent intestinal surgery, ano-perineal abscess, bowel obstruction, haemodynamic instability, anaemia, acute kidney failure and elevated C-reactive protein. Consensus for the retained indicators was >88%.ConclusionsUse of this consensus checklist for the management of IBD in the emergency department may help improve standards of care and thus reduce the burden of these diseases.  相似文献   
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Summary We present a case of blindness and Anton’s syndrome in a psychiatric patient with late diagnosis of a giant frontal meningioma. The criteria for advanced diagnostic imaging in the psychiatric population are discussed. We conclude that MR or CT scan is indicated in psychiatric in-patients who fail to improve with standard psychiatric treatment. This strategy should be submitted to a cost-benefit analysis.  相似文献   
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Enhanced and non-enhanced computed tomography (CT) brain scans were performed within 72 h of surgery on 21 children in whom brain tumors had been resected totally or subtotally, and scans were repeated at varying intervals thereafter. Biopsies of the resection margins were performed in 12 patients at the end of the surgical procedure. The immediate CT scan showed enhancement in the resection margin in 13 of the 21 patients and in 9 of the 13, the enhancement disappeared on follow-up scans. There was discordance between the results of immediate CT scan examination and the biopsies of the resection margins in 7 of the 12 cases. The advantages and disadvantages of an immediate postoperative scan versus a more delayed CT scan are discussed.  相似文献   
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肝细胞癌SCT表现和相关基因表达的初步研究   总被引:1,自引:0,他引:1  
目的 探讨肝细胞癌细胞中nm2 3 H1基因和C erbB 2基因的表达和其与SCT表现的关系。方法 对 3 6例经手术病理证实且行螺旋CT动、静脉双期增强扫描的肝细胞癌病例 ,观察其SCT表现特征 ,如包膜、子灶、门静脉癌栓、肝门淋巴结转移、肿瘤的大小和强化特征。用免疫组织化学的方法检测癌组织中nm2 3 H1基因和C erbB 2基因的表达情况。结果 肝细胞癌细胞中 ,nm2 3 H1阳性 2 1例 ,阳性率为 5 8.3 % ,转移高危组 (子灶、门脉癌栓、肝门淋巴结转移 )nm2 3 H1基因的表达低于转移低危组 (P <0 .0 5 ) ;C erbB 2基因阳性 2 2例 ,阳性率为 71.1% ,C erbB 2基因的表达在中等大小肝癌组表达高于小肝癌组和大肝癌组 (P <0 .0 5 )。结论 肝细胞癌的SCT表现与nm2 3 H1和C erbB 2基因的表达有一定关系  相似文献   
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王凯 《实用医技杂志》2002,9(11):825-826
目的 :根据直肠癌的 CT表现 ,探讨 CT对直肠癌的诊断价值。方法 :回顾性分析了 5 4例经手术和 /或活检病理证实的直肠癌病人的 CT资料 ,观察其 CT征象。结果 :典型直肠癌在 CT平扫时表现为低密度的软组织块影 ,肠壁不规则增厚 ,肠腔狭窄 ,增强扫描强化较明显 ,对于判断肿瘤大小及侵犯范围的价值最大。 期 18例 , 期 2 9例 , 期5例 , 期 2例。结论 :CT为直肠癌早期诊断 ,临床分期 ,判断治疗效果提供可靠依据  相似文献   
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CT-脑立体定向手术的临床应用   总被引:3,自引:0,他引:3  
目的 评价CT-脑立体定向手术的临床应用价值。方法 应用CT-脑立体定向仪完成28例次脑立体定向手术,分析其临床诊疗效果。结果 立体定向活检术10例,术后病理诊断明确;定向开放手术12例,病灶一次切除;立体定向穿刺分流术6例,术后症状改善明显。手术均一次成功,无手术并发症。结论 CT-脑立体定向手术能精确定位,确定最佳手术路径,为颅内多种疾患的诊断和治疗提供新的方法。  相似文献   
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