Muscle cross-section measurement by magnetic resonance imaging

Summary Muscle cross-section areas were measured by magnetic resonance imaging (MRI) in the thigh of a human cadaver,. the results being compared with those obtained by photography of corresponding anatomic macroslices. A close correlation was found between MRI and photographic evaluation, differences between the methods ranging from nil to 9.5%, depending on the scan position and the muscle groups. In vivo MRI measurements were performed on 12 female and 16 male students, the objectivity, the test-retest reliability and the variability of the MRI measurements being studied by fixing the scan position either manually or by coronary scan. The latter method appeared to be more objective and reliable. The coefficients of variation for muscle cross-section areas measured by MRI were in the range of those for the planimetry of given cross-section areas. Allowing for differentiation between several small muscle bundles in a given area, MRI proved to be a suitable method to quantify muscle cross-sections for intra- and interindividual analysis of muscle size.     

动脉顺应性及其影响因素

动脉顺应性又称动脉弹性，反映血管内皮功能。已成为预测心血管疾病的重要危险因素。无创测量动脉弹性的方法在临床上已有一定程度的应用。各种方法具有其各自适用范围及局限性。多种干预手段可以影响动脉弹性。合理测量及维持正常的动脉弹性可延缓多种心血管疾病的发生及发展。     

CVI-Q检测颈动脉血流量的临床应用价值

目的 :用彩色速度显像定量 (CVI Q)技术测定颈动脉血流量并给出青年组正常参考值。方法 :应用传统的多普勒法及CVI Q法对正常 5 0名在校四年级大学生进行左、右颈总动脉血流量的测定比较。结果 :单侧颈总动脉血流量传统法测定为 (789.49± 15 3 .40 )ml·min-1,CVI Q法为 (3 92 .85± 63 .95 )ml·min-1,两者有显著性差异 (P <0 .0 0 1) ,男女之间、左右之间无明显差异 ,S/D、RI和PI 3组数据两两之间亦无显著性差异。结论 :CVI Q是一种实用、无创、简便、可靠的测量方法 ,具有良好的临床应用价值     

Effect of artifacts due to flowing blood on the reproducibility of phase-contrast measurements of myocardial motion

The reproducibility of myocardial motion trajectories calculated from cine phase-contrast (PC) velocity data is reduced by artifacts due to the inconsistent motion of intracardiac blood. Spatial presaturation reduces these artifacts but requires a longer sequence TR, with a potentially negative effect on trajectory accuracy and reproducibility. We investigated the effect of spatial presaturation on trajectory reproducibility. A midventricular transaxial slice was imaged in five normal volunteers. The same slice was imaged three times each with sequences using spatial presaturation or not. Because the most serious artifacts originate in the heart chambers and propagate in the phase-encoded direction, myocardial regions that were in line with the heart chambers (in the phase-encode direction) had the highest artifact level in the scans without spatial presaturation. The reproducibility of trajectories for regions placed in these areas (the anterior wall, septum and posterior wall in the transaxial scans with phase encoding in the anterior-posterior direction) improved by a factor of two when presaturation was used (P < .001). In areas that were not in line with the heart chambers (eg, the anterior aspect of the lateral wall in the transaxial scans), the effect of presaturation was not significant. These results correlate well with the measured reduction in artifact level. The reproducibility of myocardial motion trajectories over large areas of the heart is improved to approximately 1 mm when presaturation is used. Therefore, use of presaturation is recommended for myocardial motion studies using cine PC velocity data.     

The positive automatic thoughts questionnaire (ATQ-P) and the automatic thoughts questionnaire—Revised (ATQ-RP): Equivalent measures of positive thinking?

We examined two recently developed measures of positive automatic thought, the Positive Automatic Thoughts Questionnaire (ATQ-P) and the Automatic Thoughts Questionnaire—Revised (ATQ-RP). Internal consistency, concurrent validity, and convergent and discriminant validity were addressed. Two hundred one undergraduates completed self-report measures of positive automatic thoughts, negative automatic thoughts, depressive symptoms, anxiety symptoms, and positive affectivity. The ATQ-P and ATQ-RP both showed high internal consistency, strong negative associations with depressive symptoms, specificity to depressive symptoms rather than anxiety symptoms, an average state-of-mind (SOM) ratio in the positive dialogue range, and a stronger relation with each other than with a measure of positive affectivity. The only notable difference between the measures was a significantly lower mean score (correcting for number of items) on the ATQ-RP. This paper is based on a thesis completed by the first author, under the supervision of the second author, in partial fulfillment of the requirements for the Master of Arts degree at American University. We are grateful to thesis committee members Lorah Dorn and Jim Gray for feedback on this material.     

Health status measurement in Parkinson's disease: validity of the PDQ-39 and Nottingham Health Profile.

We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease.     

Computation of Time-Constant Histograms from the Forced Expired Volume-Time Curves

An efficient BASIC program was established on Apple-Ⅱmicrocomputer with the CHESTAC-35F pulmonary function testing system tocalculate the time-constant histogram from the spirogram.By a set of analogousstudies,we confirmed that the recovered time-constant histogram was within onecompartment of the assumed one and that the root of mean square values of theresiduals between the experimental and model volume-time curves was 0.02.Infour healthy adult subjects,the mean value of time-constant histograms(TCx)hadthe variation coefficient 6.6％.The results show that our method is reliable andreproducible,and it can be used for clinical investigation.     

R波相关振动法血压测量

为了提高振地血压测量的准确性，提出了一咱基于心电Ｒ波与血压振动波之间相关性，识别振动信号的一种抗干扰方法＝－Ｒ波相关法，结合振动波形特征识别，该方法可有效地提取信号，消除干扰影响，该算法已在１６位８０９８单片机上实现，本文同时给出了程序的详细流程图。     

'Not everything that can be counted counts and not everything that counts can be counted'– towards a critical exploration of modes of satisfaction measurement in sheltered housing

This paper reflects on a research project funded by a consortium of leading sheltered housing (SH) providers and their regulatory body, the Housing Corporation. The project aimed to ascertain which aspects of SH older people perceived to be central to their satisfaction and the methods they judged most appropriate to measuring this. We outline key policy developments of importance to SH (specifically the development of performance measurement regimes), and changes in the nature of SH, which are driving providers to re‐evaluate how they measure user satisfaction. We discuss the aims of the project, our methodology and findings, and conclude by raising critical questions about the process of measuring satisfaction within an increasingly managerialised housing system. We argue that this favours standardised methods of information gathering (such as questionnaires) rather than engage with clients in order to develop methods and systems capable of eliciting qualitative issues of concern to them. Our conclusions are, we believe, applicable to health and social care provision, where similar tensions exist around performance measurement and user satisfaction.     

正常成人脑外段视神经的MRI研究

目的 评价正常成人视神经-眼平面(NOP)视交叉以外段颅神经的MRI表现,建立正常标准。方法 随机选择正常成人志愿者50例,采用GB1.5T MR/i echo spood plus超导型磁共振成像仪及相控阵头线圈,成像序列包括自旋回波T1加权成像(SET1WI)和自旋回波T2加权成像(SET2WI);扫描方位以NOP平面为基准扫描。分别测量两组视神经眼球后神经膨大段直径、眶内段视神经直径、长度,管内段视神经直径及该段视神经起始至同侧视交叉的长度,后者与眶内段视神经长度之和即代表颅外段视神经的长度。结果 NOP平面上,正常人眼球后神经膨大段直径为4.2±0.56mm,眶内段直径为3.1±0.45mm、长度为24.6±2.88mm,管内段视神经直径为3.2±0.49mm,至同侧视交叉的长度为18.7±2.40mm,颅外段视神经的长度为43.3±3.83mm。统计分析,正常成人组内性别和年龄、双侧视神经之间无显著差异。 结论 NOP平面评价视神经有很大优势,MRI可以很好显示视神经的形态,是研究其解剖和疾病的有效检查手段。