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951.
目的:研究口腔COPT和CBCT受检者的体表辐射特征,做好全口腔影像检查的辐射防护。方法应用长杆电离室和X射线多功能检测仪,采用非介入式方法测试COPT和CBCT影像接收器处的辐射剂量,计算受检者入射体表空气比释动能和空气比释动能率。结果在最小技术条件下,CBCT和COPT受检者入射体表空气比释动能分别为0.21、0.13 mGy,空气比释动能率分别为20.10、8.65μGy/mAs。在最大技术条件下,CBCT和COPT受检者入射体表空气比释动能分别为20.05、4.49 mGy,空气比释动能率分别为178.2、21.02μGy/mAs。在临床常用技术条件下, CBCT(84~90)kV和COPT(62~70)kV受检者入射体表空气比释动能分别为(16.61~18.62)和(0.87~3.12)mGy,空气比释动能率分别为(105.3~138.2)和(11.42~14.42)μGy/mAs。结论口腔CBCT受检者入射体表辐射剂量高于COPT。口腔临床和放射医生要遵守辐射防护三原则,合理应用COPT与CBCT。 相似文献
952.
目的 评价64排CT冠脉成像(CTA)及冠脉造影对心肌桥的诊断对照.方法选择我院2010年~2013年间100例临床怀疑冠心病,经冠脉CTA及冠脉造影检查的患者,然后对冠脉CTA及冠脉造影的结果进行对比分析.结果 本组经冠脉CTA检出心肌桥16例病例中,冠脉造影只检出6例.结论 64排冠脉CTA对心肌桥的检出率明显高于冠脉造影.64排CT冠脉成像可以清晰而且直观地显示冠状动脉及其细小分支,并精确显示血管的走行情况、管壁的粥样斑块及钙化、血管的狭窄程度等,与目前诊断冠脉的金标准冠脉造影相比,本检查方法不但对心肌桥的检出率明显高于前者,而且为无创性检查、费用低廉.冠脉GTA可以作为冠心病高危人群无创性筛选检查及冠脉支架、搭桥术后随访手段. 相似文献
953.
Zaid Ammari Ali A. Hasnie Mohammed Ruzieh Osama Dasa Mohammad Al-Sarie Pinang Shastri Nikita Ashcherkin Pamela S Brewster Christopher J. Cooper Rajesh Gupta 《The American journal of the medical sciences》2021,361(4):445-450
BackgroundComputed Tomography (CT) Pulmonary Angiography is the most commonly used diagnostic study for acute pulmonary embolism (PE). Echocardiogram (ECHO) is also used for risk stratification in acute PE, however the diagnostic performance of CT versus ECHO for risk stratification remains unclear.MethodsCT and ECHO right ventricle (RV) and left ventricle (LV) diameters were measured in a retrospective cohort of patients with acute PE. RV:LV diameter ratios were calculated and correlation between CT and ECHO RV:LV ratio was assessed. Sensitivity and specificity for the composite adverse events endpoint of mortality, respiratory failure requiring intubation, cardiac arrest, or shock requiring vasopressors within 30 days of admission were assessed for CT or ECHO derived RV:LV ratio alone and in combination with biomarkers (troponin or B-type natriuretic peptide).ResultsA total of 74 subjects met the inclusion criteria and had a mean age of 62±18 years. The proportion of patients with RV:LV >1 was similar when comparing CT (37.8%) versus ECHO (33.8%) (P = 0.61). A statistically significant correlation was found between CT derived and ECHO derived RV:LV diameter ratio (r = 0.832, P < 0.001). The sensitivity and specificity to predict 30-day composite adverse events for CT versus ECHO derived RV:LV diameter ratio >1 together with positive biomarker status was similar with sensitivity and specificity of 87% and 41% versus 87% and 42%, respectively.ConclusionsIn patients with acute PE, CT and ECHO RV:LV diameter ratio correlate well and identify similar proportion of PE patients at risk for early adverse events. These findings may streamline risk stratification of patients with acute PE. 相似文献
954.
955.
Kazuhiro Kitajima Shingo Yamamoto Yusuke Kawanaka Hisashi Komoto Kimihiro Shimatani Takeshi Hanasaki Motohiro Taguchi Seiji Nagasawa Yusuke Yamada Akihiro Kanematsu Koichiro Yamakado 《Medicine》2021,100(23)
This study aimed to evaluate the clinical use of choline-PET/CT for discriminating viable progressive osteoblastic bone metastasis from benign osteoblastic change induced by the treatment effect and evaluating the response of bone metastasis to treatment in metastatic castration-resistant prostate cancer (mCRPC) patients. Thirty patients with mCRPC underwent a total of 56 11C-choline-PET/CT scans for restaging, because 4 patients received 1 scan and 26 had 2 scans. Using 2 (pre- and post-treatment) 11C-choline-PET/CT examinations per patient, treatment response was assessed according to European Organization for Research and Treatment of Cancer (EORTC) criteria in 20 situations, in which only bony metastases were observed on 11C-choline-PET/CT scans. Viable bone metastases and osteoblastic change induced by the treatment effect were identified in 53 (94.6%) and 29 (51.8%) of 56 11C-choline-PET/CT scans, respectively. In 27 cases (48.2%), 11C-choline-PET/CT scans could discriminate the 2 entities. The mean SUVmax of the metastatic bony lesions was 5.82 ± 3.21, 5.95 ± 3.96, 6.73 ± 5.04, and 7.91 ± 3.25 for the osteoblastic, osteolytic, mixed, and invisible types, respectively. Of the 20 situations analyzed, CMR, PMR, SMD, and PMD, as determined by the EORTC, were seen in 1, 2, 3, and 14 cases, respectively. Of the 13 patients with increasing PSA trend, all 13 showed PMD. Of the 2 patients with PSA response of <50%, both 2 showed SMD. Of the 5 patients with PSA response of ≥50%, 1 showed CMR, 2 showed PMR, 1 showed SMD, and 1 showed PMD. Choline-PET/CT is very useful to discriminate viable progressive osteoblastic bone metastasis from osteoblastic change, and assess treatment response of bone metastases in mCRPC. 相似文献
956.
Background:This meta-analysis aimed to systematically estimate the prevalence of comorbid bronchiectasis in patients with asthma and to summarize its clinical impact.Methods:Embase, PubMed, and Cochrane Library electronic databases were searched to identify relevant studies published from inception until March 2020.Study Selection:Studies were included if bronchiectasis was identified by high-resolution computed tomography. Outcomes included the prevalence of bronchiectasis and its association with demographic characteristics and indicators of asthma severity, including results of lung function tests and the number of exacerbations.Results:Five observational studies with 839 patients were included. Overall, the mean prevalence of bronchiectasis in patients with asthma was 36.6% (307/839). Patients with comorbid bronchiectasis had lower forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) (MD: −2.71; 95% CI: −3.72 to −1.69) and more frequent exacerbations (MD: 0.68; 95% CI: 0.03 to 1.33) than those with asthma alone, and there was no significant difference of sex, duration of asthma and serum levels of immunoglobulin(Ig)Es between asthmatic patients with or without bronchiectasis.Conclusion:The presence of bronchiectasis in patients with asthma was associated with greater asthma severity. There are important therapeutic implications of identifying bronchiectasis in asthmatic patients. 相似文献
957.
Objective:To establish whether early use of magnetic resonance imaging (MRI) or computed tomography (CT) influences treatment and outcome of patients with low back pain.Methods:This study will be implemented from March 2021 to March 2022 at Huzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University. The experiment was granted through the Research Ethics Committee of Huzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University (R609320987). Patients who have symptomatic lumbar spine disorders at presentation are eligible for the trial if there is clinical uncertainty about the need for imaging (MRI or CT). Patients are excluded who required immediate referral for imaging (those who had signs suggestive of serious abnormalities or disease or who required surgical intervention), who have undergone MR imaging or CT of the spine within 1 year, who do not need imaging, and who have pain of a nonspinal origin. The primary outcome measure is the Aberdeen Low Back Pain (ALBP) score. Other principal outcome measure is the Short Form 36.Results:Table 1 will show the quality of life outcome measures between groups.Conclusion:This study may guide the policy makers to develop an evidence-based protocol to assess the effect of early use of MRI or CT in the treatment of patients with low back pain. 相似文献
958.
Young Hak Chung Byoung-Kwon Lee Hyuck Moon Kwon Pil-Ki Min Eui-Young Choi Young Won Yoon Bum-Kee Hong Se-Joong Rim Jong-Youn Kim 《Medicine》2021,100(9)
Lipoprotein a (Lp (a)) and coronary artery calcification (CAC) are markers of coronary artery and cardiovascular diseases. However, the association between Lp (a) and CAC in asymptomatic individuals remains unclear. In this study, we aimed to determine the influence of Lp (a) on CAC in asymptomatic individuals.We included 2019 asymptomatic Korean adults who underwent testing for a coronary artery calcium score (CACS) and Lp (a) at the Gangnam Severance Hospital Health Checkup Center in Korea from January 2017 to August 2019. Participants were divided into 2 groups: CACS = 0 and CACS > 0. Factors affecting the CACS were analyzed by sex. Because age is a major risk factor for atherosclerosis, ≥45 years in men and ≥55 years in women, we further divided participants into 4 subgroups (≥45 and <45 in men, ≥55 and <55 in women). Factors affecting the CACS in the 4 groups were analyzed.There was a positive correlation between the CACS and traditional cardiovascular risk factors. Lp (a) positively correlated with the CACS in men (P < .01) and remained significant after multivariable logistic regression (P < .01). The same result was observed in men aged ≥45 years (P < .01).Lp (a) is an independently associated factor of CAC and a marker of coronary atherosclerosis in asymptomatic men aged ≥45 years. In asymptomatic men aged ≥45 years, Lp (a) should be measured, and intensive Lp (a)-lowering treatment should be considered. 相似文献
959.
Objectives:Controversies emerge over routine performances of whole-body computed tomography (WBCT) in patients with blunt polytrauma. The existing randomized and non-randomized evidence is inconclusive, and during observations of non-trauma, incidental findings, detected by WBCT, have left uncertainty regarding their consequences and optimal management. Additionally, previous meta-analyses have failed to address the limitations of primary studies and issues associated with incidental findings. Therefore, we planned a new systematic review to address these points.Methods:We will search the PubMed, EMBASE, and Cochrane Central databases from inception to December 31, 2020, with no language restriction and perform full-text evaluation of potentially relevant articles. We will include prospective and retrospective studies with a single-gate design that assessed diagnostic accuracy and/or yield of WBCT to detect traumatic injuries, and studies that assessed incidental findings detected by WBCT. Additionally, we will include randomized controlled trials and non-randomized comparative studies that assessed the effectiveness of WBCT against conventional care, including selective computed tomography (CT). Studies of patients of all ages with blunt traumatic injuries, assessed at an emergency department, will be included. Two reviewers will extract data and rate the study validity via standard quality assessment tools. The primary outcome of interest will be reduction in mortality. Our secondary outcomes will include diagnostic accuracy and yield, detection of incidental findings and clinical outcomes associated with these detections, and improvement in other non-mortality clinical outcomes. We will qualitatively assess study, patient, and intervention characteristics and clinical outcomes. If appropriate, we will perform random-effects model meta-analyses to obtain summary estimates. Finally, we will assess the certainty of evidence by the grading the quality of evidence and strength of recommendations.Ethics and dissemination:Ethics approval is not applicable, as this is a secondary analysis of publicly available data. The review results will be submitted for publication in peer-reviewed journals.Prospero registration:CRD42020187852. 相似文献
960.
Michael E. Ballard Mark A. Mandelkern John R. Monterosso Eustace Hsu Chelsea L. Robertson Kenji Ishibashi Andy C. Dean Edythe D. London 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(7)