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81.

Purpose

Early outcome prediction after suicidal hanging is challenging in comatose survivors. We analysed the early patterns of brain diffusion-weighted magnetic resonance imaging (DWI) abnormalities in comatose survivors after suicidal hanging.

Methods

After suicidal hanging, 18 comatose survivors were prospectively evaluated from January 2013 to December 2016. DWI was performed within 3?h after hanging in comatose survivors. We evaluated Utstein style variables and analysed abnormal spatial profile of signal intensity on DWI, brain apparent diffusion coefficient (ADC) values, and qualitative DWI scores to predict neurological outcomes.

Results

All hanging associated cardiac arrest (CA) patients demonstrated bad neurological outcomes; 80% of non-CA comatose patients experienced good neurological outcomes. In hanging survivors with CA, cortical grey matter structures and deep grey nuclei exhibited profound ADC reductions and high DWI scores within 3?h after hanging, which was associated with diffuse anoxic brain damage with poor cerebral performance categories scores. CA comatose survivors had significantly lower ADC values and higher DWI scores compared to non-CA comatose survivors in the cortex and deep grey nuclei.

Conclusion

Although the presence of CA is the most important clinical prognosticator in hanging-associated comatose survivors, HSI abnormalities and low ADC values in the cortex and deep grey nuclei on DWI performed within 3?h after hanging are well-correlated with unfavourable outcomes regardless of therapeutic hypothermia. Therefore, early DWI may increase the sensitivity of poor outcome prediction and may be an effective combinatorial screening method when available prognostic variables are not reliable or conclusive.  相似文献   
82.
ObjectivesTo describe recent trends in advanced imaging and hospitalization of emergency department (ED) syncope patients, both considered “low-value”, and examine trend changes before and after the publication of American College Emergency Physician (ACEP) syncope guidelines in 2007, compared to conditions that had no changes in guideline recommendations.MethodsWe analyzed 2002–2015 National Hospital Ambulatory Medical Care Survey data using an interrupted-time series with comparison series design. The primary outcomes were advanced imaging among ED visits with principal diagnosis of syncope and headache and hospitalization for ED visits with principal diagnosis of syncope, chest pain, dysrhythmia, and pneumonia. We adjusted annual imaging and hospitalization rates using survey-weighted multivariable logistic regression, controlling for demographic and visit characteristics. Using adjusted outcomes as datapoints, we compared linear trends and trend changes of annual imaging and hospitalization rates before and after 2007 with aggregate-level multivariable linear regression.ResultsFrom 2002 to 2007, advanced imaging rates for syncope increased from 27.2% to 42.1% but had no significant trend after 2007 (trend change: ?3.1%; 95%CI ?4.7, ?1.6). Hospitalization rates remained at approximately 37% from 2002 to 2007 but declined to 25.7% by 2015 (trend change: ?2.2%; 95%CI ?3.0, ?1.4). Similar trend changes occurred among control conditions versus syncope, including advanced imaging for headache (difference in trend change: ?0.6%; 95%CI ?2.8, 1.6) and hospitalizations for chest pain, dysrhythmia, and pneumonia (differences in trend changes: 0.1% [95%CI ?1.9, 2.0]; ?0.9% [95%CI ?3.1, 1.3]; and ?1.2% [95%CI ?5.3, 2.9], respectively).ConclusionsBefore and after the release of 2007 ACEP syncope guidelines, trends in advanced imaging and hospitalization for ED syncope visits had similar changes compared to control conditions. Changes in syncope care may, therefore, reflect broader practice shifts rather than a direct association with the 2007 ACEP guideline. Moreover, utilization of advanced imaging remains prevalent. To reduce low-value care, policymakers should augment society guidelines with additional policy changes such as reportable quality measures.  相似文献   
83.
目的 探索单能量成像结合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASIR)及自动能谱协议选择(automatic spectral imaging mode selection,ASIS)技术在个体化降低患者门静脉造影辐射剂量、对比剂剂量中的应用价值。方法 回顾性收集华中科技大学同济医学院附属协和医院2017年1月至2017年4月120例临床需进行上腹部增强检查的受检者资料(男80例,女40例),按扫描方案分为3组,每组各40例。A组采用常规120 kVp扫描,噪声指数(NI)=10,对比剂用量为450 mgI/kg,图像采用50% ASIR重建;B、C两组采用能谱成像模式,NI=10(B组),NI=13(C组),对比剂用量均为300 mgI/kg,图像采用60 keV+50% ASIR重建。采用单因素方差分析比较3组图像中门静脉、肝实质的平均CT值及其差值、图像噪声、信噪比(SNR)及对比噪声比(CNR)。由两位高年资放射科医师对3组图像进行主观图像质量评分。记录患者的容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)并计算有效剂量(E)。结果 B、C两组对比剂用量较A组降低了约30%。A、B、C组图像的门静脉CT值分别为168.22±17.82、209.06±20.07、211.03±25.60,B、C组与A比较,差异有统计学意义(t=-9.625、-8.680,P<0.05)。A、B、C 3组门静脉与肝实质CT差值分别为60.01±17.01、106.63±25.83、107.72±25.39,B、C组与A组比较,差异有统计学意义(t=-9.536、-9.857,P<0.05)。SNR分别为8.48±1.41、12.64±2.94、10.77±1.94,CNR分别为5.16±1.80、8.13±2.54、7.32±1.84,图像质量评分分别为(3.53±0.68)、(4.75±0.54)和(4.53±0.64)分,B、C组的SNR、CNR和图像质量评分与A组比较,差异有统计学意义(t=-8.082、-6.064、-6.050、-5.308、-8.912、-6.779,P<0.05)。A、B、C组CTDIvol分别为(12.15±5.02)、(12.34±4.18)、(10.03±3.13)mGy,DLP分别为(348.62±155.99)、(355.56±131.07)、(287.10±92.25)mGy·cm,E分别为(5.23±2.34)、(5.33±1.97)、(4.31±1.38)mSv,相对于A、B两组,C组的CTDIvol、DLP和E差异均有统计学意义(t=2.274、2.147、2.147、2.812、2.702、2.702,P<0.05),分别降低了19%。结论 CT门静脉成像时,选择NI=13,60 keV结合50%ASIR重建及ASIS技术可以个体化降低患者的对比剂剂量和辐射剂量,并提供满足诊断要求的图像。  相似文献   
84.

Background

Myelin oligodendrocyte glycoprotein antibodies (MOG Abs) are frequently detected in pediatric acquired demyelinating syndrome (ADS), and MOG-Ab-positive ADS differs from multiple sclerosis (MS) and aquaporin-4 (AQP4)-Ab-positive neuromyelitis optica spectrum disorder (NMOSD) in terms of age distribution, therapeutic response, and prognosis.

Methods

Based on medical records, we retrospectively evaluated patients with MOG-Ab-positive NMOSD treated in the acute phase who were followed up in the chronic phase at our hospital from January 2011 to December 2017.

Results

The patients comprised two boys and two girls aged 3–12 (median, 8) years. Peak MOG-Ab titers were 1:2048 to 1:32768 (median, 1:10240), and the relapse rate ranged from 0 to 1.25 times/year (median, 0.59 times/year); no sequelae were observed in any cases. Lesions other than those of optic neuritis were distributed at the cortex in one patient, subcortical white matter in four, deep white matter in three, and brainstem in one, all of which were disseminated lesions. No lesions were found in the corpus callosum, periventricular white matter, diencephalon, and regions adjacent to the third and fourth ventricles. The lesions tended to be asymptomatic, and two patients aged >5?years had well-demarcated lesions.

Conclusion

All the patients showed disseminated lesions in the subcortical region to deep white matter, which were different from those found in MS and AQP4-Ab-positive NMOSD and were consistent with the characteristics of brain lesions in MOG-Ab-positive ADS, including other disease types.  相似文献   
85.
86.
射血分数保留的心力衰竭发病率在逐年上升。准确测量左室舒张功能有利于对该病的临床评价。目前可采用超声心动图、心脏MRI(CMRI)及其他多种检查方法评价左室舒张功能,并对舒张功能的病生理机制、舒张功能障碍分级有提示作用。其中CMRI技术的作用日益突出,包括舒张期容积-时间曲线、二尖瓣血流与肺静脉血流成像、心肌标记及其他CMRI技术。  相似文献   
87.

BACKGROUND CONTEXT

Although facet dislocations account for only 6% of cervical trauma, the consequences are often devastating. Cervical facet dislocations are associated with a disproportionate amount of spinal cord injuries; however, neurologic examination of patients is often difficult, as patients commonly present with reduced levels of consciousness. There are limited studies that have investigated the impact of spinal canal diameter and translation on neurologic injury following facet dislocations.

PURPOSE

Review a consecutive series of patients with facet dislocations to assess the impact of sagittal diameter and translation on Spinal Cord Injury (SCI).

STUDY DESIGN

Retrospective review at a level I trauma center identified 97 patients with facet dislocations.

METHODS

Between 2004 and 2014, a retrospective review at a level I trauma center identified patients with traumatic facet dislocation. Demographic data, neurologic exams, and radiographic findings were reviewed. We assessed sagittal diameter at the injury level, as well as above and below, and translation. This study has no funding source and its authors have no potential conflicts of interest-associated biases.

RESULTS

Ninety-seven patients presented with facet dislocations. Fifty-nine (61%) presented with a SCI. Those with ASIA A averaged 8.0 mm of injury level canal diameter, and ASIA E averaged 12.6 mm (p < .001). Additionally, those with ASIA A averaged 8.0 mm of translation, and ASIA E averaged 4.2 mm (p < 0.001). Two groups were created based on their general motor function. Those with ASIA A–C averaged 8.4 mm of injury level canal diameter, and ASIA D–E averaged 12.3 mm (p < .001). Those with ASIA A–C averaged 7.8 mm of translation, and ASIA D–E averaged 4.4 mm (p < .001). Receiver operating characteristic (ROC) curves demonstrated that translation was a good predictor of ASIA A–C and canal diameter was an almost perfect predictor of ASIA D–E.

CONCLUSIONS

Our data indicate that patients with greater translation and/or a smaller canal diameter at the injury level have a higher rate of SCI. Adjacent canal diameter did not correlate with neurologic injury.  相似文献   
88.
吴少平 《西部医学》2019,31(4):493-496
本文立足于促进骨骼影像学的发展,在宏观分析骨骼影像学临床应用与研究现状的基础上,指出了存在的主要问题及原因,认为骨骼影像学的再进步,有赖于从大体形态学定性到微观成分定量的思路转变和具体技术研究的突破,以及学科内部专业整合、相关学科交叉、跨学科技术协作等的思路与发展方向。  相似文献   
89.

Background

The purpose of the study was to compare cancer detection rates between 12-core transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and multiparametric magnetic resonance imaging (mpMRI)-guided target prostate biopsy (MRI-TBx) according to prostate-specific antigen (PSA) level in biopsy-naive patients.

Patients and Methods

A retrospective study was conducted in 2009 biopsy-naive patients with suspected prostate cancer (PSA ≤20 ng/mL). Patients underwent TRUS-Bx (n = 1786) or MRI-guided target prostate biopsy (MRI-TBx; n = 223) from September 2013 to March 2017 and were stratified according to each of 4 PSA cutoffs. MRI-TBx was performed on lesions with Prostate Imaging Reporting and Data System (PI-RADS) scores of 3 to 5 on mpMRI. Clinically significant prostate cancer (csPCa) was defined as Gleason ≥7. Propensity score matching was performed using the prebiopsy variables, which included age, PSA, prostate volume, and PSA density.

Results

Propensity score matching resulted in 222 patients in each group. There were significant differences between the TRUS-Bx and MRI-TBx groups in the overall detection rates of prostate cancer (41.4% vs. 55.4%; P = .003) and csPCa (30.1% vs. 42.8%; P = .005). However, across PSA cutoffs, MRI-TBx detected more prostate cancer than TRUS-Bx at PSA levels of 2.5 to <4 (29.5% vs. 56.6%; P < .001). The csPCa detection rates of TRUS-Bx and MRI-TBx did not differ significantly within the PSA cutoffs. There was a significantly higher detection rate of prostate cancer and csPCa in lesions with PI-RADS scores 4 and 5 than in those with a score of 3.

Conclusion

Prebiopsy mpMRI and subsequent targeted biopsy had a higher detection rate than TRUS-Bx in patients with prostate cancer and csPCa.  相似文献   
90.
《Clinical breast cancer》2020,20(4):e458-e468
PurposeThe eligibility for nipple-sparing mastectomy (NSM) regarding subareolar non-mass enhancement (NME) on breast magnetic resonance imaging (MRI) was not clear. This study aimed to evaluate the eligibility for NSM according to the NME-to-nipple distance on preoperative breast MRI.MethodsWe identified patients with breast cancer who underwent mastectomy with NME suspected of malignancy in the subareolar region on preoperative breast MRI. The incidence of nipple invasion was pathologically evaluated according to the NME-to-nipple distance on breast MRI, and the clinicopathologic factors related to pathologic nipple invasion were analyzed.ResultsOf 137 patients, 55 (40.1%) had NME extension to the nipple, 53 (38.7%) had radiologic distance less than 2 cm, and 29 (21.2%) had radiologic distance of 2 cm or more. The rate of pathologic nipple invasion was 52.7% (29 of 55) in patients with NME extension to nipple, 7.5% (4 of 53) in patients with NME-to-nipple distance less than 2 cm, and 3.4% (1 of 29) in patients with NME-to-nipple distance of 2 cm or more (P < .001). NME extension to the nipple was an independent risk factor for pathologic nipple invasion (odds ratio 21.702; 95% confidence interval, 2.613–180.225; P = .004). The survival outcome was not different between NSM and conventional total mastectomy/skin-sparing mastectomy in patients with radiologic distance less than 2 cm, but without NME extension to the nipple.ConclusionsNSM is an acceptable procedure in patients with breast cancer with a low incidence of pathologic nipple invasion when there is no evidence of NME extension to the nipple on preoperative breast MRI.  相似文献   
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