Decision making in diagnostic radiology

Radiology can be more interesting if the principles of decision making are understood and used to the advantage of the radiologist, referring clinician and patient. This article seeks to revise the principles that radiologists use intuitively. Particular emphasis is placed on the importance of the pre-test probability, as it can be shown to: (i) vary with the referral pool of patients; (ii) be a major determinant of the amount of additional information gained from the test; (iii) alter the sensitivity and specificity of the test; and (iv) determine largely the significance of a positive or negative test result. An investigation helps a clinician by providing information that will move the probability of disease above an action threshold or below its exclusion threshold. If this does not occur as a result of one study, another is selected. This article also describes the factors involved in such a decision tree analysis, as well as discussing the reasons for both selecting a particular examination and deciding when a test should not be performed.     

Path analysis and sib-pair linkage

When the distance between linked loci is expressed in terms of the correlation between the identity-by-descent (idb) values of the loci, then a path model may be used to order loci with data on sib-pairs and their parents. The relationship between the recombination fraction and the correlation coefficient is developed and a method for fitting a covariance matrix predicted by a specific ordering of loci to an observed covariance matrix is proposed. © 1993 Wiley-Liss. Inc.     

Perimetric variability: Importance of criterion level

Perimetry suffers from considerable variability of results. A new technique for estimating individual criterion levels in normal subjects exposes the important role of psychological variables. The analysis depends on features peculiar to acuity perimetry. It can be accommodated in the regular examination. The results can be used to compensate for practice effects in serial examinations and to tighten the range of normal limits. The reduction in variation between normal subjects amounted to 57 per cent.     

测定血清及尿β2微球蛋白评估健康老年人肾功能的价值

测定72例健康老年人（60-84岁）和65例健康青中年人（20-50岁）血清和尿β2微球蛋白（β2m)，发现前血清β2m浓度比后明显增高（p<0.001)；老年组≥70岁尿液β2m浓度也明显增高（p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低，以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。     

Minimizing macrovessel signal in cerebral perfusion imaging using independent component analysis.

The pronounced susceptibility effect of macrovessels in MR bolus-tracking studies induces spots of artificially high blood flow and volume in perfusion parameter images. These high-intensity regions impede the detection of perfusion changes and lead to elevated perfusion parameters in adjacent tissues. The purpose of this work was to explore postprocessing methods to reduce the influence of macrovessel signal in dynamic MRI. After data reduction was performed with the use of a principal component analysis (PCA), an independent component analysis (ICA) was applied to separate signal components of different compartments. Based on this decomposition, the dynamic time series were reconstructed with minimized contributions of macrovessel signal and noise. The influence of the temporal resolution and signal-to-noise ratio (SNR) of the source data were investigated by means of a simulation study. A region-of-interest (ROI)-based analysis of corrected and uncorrected in vivo data demonstrated that the influence of arteries and veins was reduced at least by 50%, while gray matter (GM) and white matter (WM) tissues were nearly unaffected by the correction process. Hemodynamic parameter images of the cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) were calculated from corrected and uncorrected scans. The corrected parameter images showed a clearly reduced macrovessel signal and an improved perceptibility of microvascular perfusion changes compared to the uncorrected ones.     

6种中药制剂治疗急性脑梗死的成本-效果分析

目的：运用药物经济学的方法对在我院应用的6种中药注射液进行成本-效果分析。方法：271例急性脑梗死患者依据药物治疗方案不同分为6组，即血塞通组、舒血宁组、苦碟子组、疏血通组、川芎嗪组、丹红组，分别观察疗效，并运用药物经济学的方法进行成本-效果分析。结果：疏血通组的成本为3 419.90元，总有效率最高（91.84%），6组间增量成本-效果最低。因此疏血通组是较为合理、经济的方案。     

128例肾输尿管结石临床分析

目的为探讨肾输尿管结石的临床特点,以提出更好的防治措施。方法对原西南师范大学医院1997-2004年治疗的128例肾输尿管结石病例的临床资料进行统计分析。结果本组病例男女之比为2.05∶1,29岁以下发病103例,占80.5%。2001年起发病呈上升趋势,2003年最高。每年9-10月是发病高峰,占本组病例的31.2%。经体外震波碎石99例,3个月结石排净率为83%,与文献报道的基本一致。结论该校肾输尿管结石患者,男性多于女性,30岁以下居多。发病近年增加,体外震波碎石疗效好。     

甲状腺素治疗新生儿硬肿症疗效观察

目的 观察甲状腺素治疗新生儿硬肿症的疗效。方法 将63例随机分为甲状腺素治疗组(简称治疗组)32例,对照组31例,两组均给予综合治疗,治疗组加用甲状腺素片每天4～6mg/kg口服,疗程1周。结果 治疗组与对照组总有效率分别为87.5％、61.3％,有显著差异(P<0.05)。两组间复温时间分别为7.0±3.7h、16.5±11.2h,硬肿消退时间分别为4.1±1.9天、6.9±3.1天,住院时间分别为6.9±3.1天、9.8±4.6天,治疗组比对照组明显缩短,有显著差异(P<0.01)。结论 新生儿硬肿症使用甲状腺素治疗可明显提高治愈率,缩短病程,且使用方便,无副作用。     

颈动脉加压注射复方维脑路通合剂治疗脑梗死180例临床分析

本科自 2 0 0 0年 6月以来 ,采用颈动脉加压注射复方维脑路通合剂治疗脑梗死 180例 ,并与静脉给药组相比较 ,现总结如下。1　资料与方法1.1　临床资料　治疗组 180例 ,男 117例 ,女 6 3例 ,年龄 37岁～ 76岁 ,平均年龄 5 7.2 0岁。均为颈内动脉系统脑梗死。其中大面积脑梗死 4例 ,脑梗死 85例 ,腔隙性脑梗死 91例。大面积脑梗死组 4例 ,其梗死灶涉及 2个脑叶或以上 ,均无意识障碍及脑疝者 ,在发病 10d后即脑水肿高峰期后开始颈动脉加压注射。治疗组病例选择除下列禁忌 :①严重高血压病(血压≥ 2 6 .6 / 16kPa) ;②脑出血、出血性梗死 ;③严…