Lung Ultrasound for the Emergency Diagnosis of Pneumonia,Acute Heart Failure,and Exacerbations of Chronic Obstructive Pulmonary Disease/Asthma in Adults: A Systematic Review and Meta-analysis

Background

Lung ultrasound can accelerate the diagnosis of life-threatening diseases in adults with respiratory symptoms.

导航辅助脊柱胸腰段椎弓根钉植入的临床应用

目的探讨临床运用计算机影像导航技术引导脊柱胸腰段椎弓根钉植入的准确性。方法2003年5月-2007年5月，29例患者接受116枚计算机影像导航技术引导脊柱胸腰段椎弓根钉植入手术治疗，T10-T1250枚胸椎弓根钉，L1-L3 66枚腰椎弓根钉。术中记录椎弓根钉植入所需时间及C-臂透视工作次数，椎弓根钉植入完成后，即行C-臂正侧位摄片并与导航路径进行比较测量。术后CT进行椎弓根层面扫描，根据椎弓根钉与椎弓根皮质问关系分为四级：A=在椎弓根内；B=突破皮质，〈2mm；C=突破皮质，2-4mm；C=突破皮质，〉4mm。结果术后CT椎弓根位置扫描显示：A级101枚（87．07％）；B级10枚（8．62％）；C级2枚（1．72％）；D级3枚（2．59％）。1枚椎弓根钉植入平均所需时间：2．73±0．64min（1．15～4．02min）。下胸椎9枚（7．75％）胸椎弓根钉突破皮质，上腰椎6枚（5．17％）腰椎弓根钉突破皮质，且临床观察未发现与椎弓根钉突破皮质相关的神经血管等并发症。植入的椎弓根钉C-臂正侧位摄片与导航路径吻合比较，进钉点均差2．6mm（最大3．1mm），角度均差3．3°（最大5．4°）。结论计算机影像导航辅助脊柱胸腰段椎弓根钉植入，提供二维、多平面实时显示，保证了脊柱胸腰段椎弓根钉植入的准确性及安全性，明显减少放射线的暴露强度。     

CT导引下胸部病变穿刺活检影响诊断正确率因素分析

目的 :探讨影响CT导引下胸部病变穿刺活检诊断正确率的因素。方法 :复习有手术病理、临床和影像学随访的胸部病变CT导引下穿刺活检 2 4 4例 ,依据手术病理、治疗反应及临床随访结果对活检病灶作出最终诊断 ,观察因素包括患者相关因素 (性别、年龄、有无肺气肿 )、病灶相关因素 (病灶大小、位置、有无空腔及病灶深度 )和操作相关因素 (患者的体位 )。结果 :胸部病变CT导引下穿刺活检诊断正确率为 82 .4 % ( 2 0 1 /2 4 4)。活检诊断正确率与病灶大小有关 ,诊断正确组和非正确组病灶大小分别为 3 .97± 1 .80cm和 3 .1 1± 1 .4 4cm(P <0 .0 5 )。患者性别、年龄、有无肺气肿、病灶位置、深度、有无空腔及患者体位对穿刺活检诊断正确率的影响无统计学意义。结论 :病灶大小是影响CT导引下胸部病变穿刺活检诊断正确率的主要因素     

The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts

The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 7–70). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique.     

The accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation values in piglets

A piglet model was used to evaluate the accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation (SaO₂) values. In eight anaesthetized piglets, the inspired oxygen concentration was varied from 30% to 6% resulting in a SaO₂ range from 100% to 15%. Paired data of the Opticath® fiberoptic catheter, which was placed in the descending aorta, and blood sample SaO₂ values assessed by a multiwavelength oximeter, were analysed. After in vitro calibration according to the manufacturer's instruction, the fiberoptic catheter started to underestimate the SaO₂ below 78%, worsening towards lower SaO₂ values. The overall bias was -3. 4% and the precision 3. 8%. An off-line fit with a non-linear model resulted in a standard deviation of residuals of 2. 6%. After several in vivo calibration adjustments when the Fiberoptic oximeter deviated more than 4% from the blood sample value, the bias was eliminated over the total SaO₂ range and the precision was 3. 7%. The Opticath® fiberoptic oximeter could have an accuracy for the whole SaO₂ range between 15–100% close to the accuracy of the multiwavelength oximeter, when the fiberoptic oximeter is adapted for the underestimation below 78% SaO₂.     

A mixture of experts network structure for modelling Doppler ultrasound blood flow signals

Mixture of experts (ME) is a modular neural network architecture for supervised learning. This paper illustrates the use of ME network structure to guide modelling Doppler ultrasound blood flow signals. Expectation-Maximization (EM) algorithm was used for training the ME so that the learning process is decoupled in a manner that fits well with the modular structure. The ophthalmic and internal carotid arterial Doppler signals were decomposed into time-frequency representations using discrete wavelet transform and statistical features were calculated to depict their distribution. The ME network structures were implemented for diagnosis of ophthalmic and internal carotid arterial disorders using the statistical features as inputs. To improve diagnostic accuracy, the outputs of expert networks were combined by a gating network simultaneously trained in order to stochastically select the expert that is performing the best at solving the problem. The ME network structure achieved accuracy rates which were higher than that of the stand-alone neural network models.     

Diagnostic value of DNA flow cytometry combined with fine needle aspiration biopsy in lymphomas

The nuclear DNA content of cells from 45 malignant lymphomas and from 60 benign lymph nodes obtained by fine needle aspiration was analysed to investigate the diagnostic value of DNA flow cytometry combined with routine diagnostic cytology in lymphomas. DNA aneuploidy was found in 43 per cent of lymphomas of high grade malignancy (NCI Working Formulation) but only rarely in lymphomas of intermediate- or low-grade malignancy or in Hodgkin's disease, and never in benign lymph nodes. The median percentage of proliferative cells (S + G2/M) was 22.6 per cent in diploid high-grade lymphomas, 15.3 per cent in intermediate-, and 8.1 per cent in low-grade lymphomas, as compared with 4.9 per cent in benign lymph nodes (P less than 0.0001). If the presence of DNA aneuploidy or more than 12 per cent of proliferative cells is used as a criterion for malignancy, the diagnostic accuracy of DNA flow cytometry in detecting lymphoma is 81 per cent. DNA flow cytometry suggested correct diagnosis in 10 of the 19 false positive, false negative, or indeterminate cytological findings encountered during the study. It is concluded that DNA flow cytometry combined with fine needle aspiration biopsy has diagnostic value in lymphomas, but false negative results are common especially in low-grade lymphomas; the method should therefore be used in conjunction with light microscopy.     

一种新型18°×4扇形网织红细胞计数窥盘

目的研制一种新型18°×4扇形网织红细胞计数窥盘。方法使用安瓿刀在玻片上刻制,再与国际血液学标准化委员会(ICSH)推荐的Miller窥盘进行网织红细胞对比分析。结果新型网织红细胞计数窥盘和ICSH推荐的Miller窥盘的准确度是一致的,但新型网织红细胞计数窥盘的精密度显著优于ICSH推荐的Miller窥盘。其参考范围也与其他报道一致。结论新型网织红细胞计数窥盘做法简单,不需特殊设备,值得推广应用。