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1.
ObjectivesThe purposes of this study were to (1) investigate the limits of measurements on scout view in three computed tomography axes, x, y and z and (2) develop a model to provide better understanding of measurement accuracy.MethodsFor the first objective, anteroposterior and lateral scout views of a Catphan phantom 200 mm in diameter and length were acquired with a GE scanner at 21 different table heights. Phantom measurements on scout view were performed by two experienced readers. The comparison of their measures provided estimation of precision. The accuracy was assessed by determining the bias, calculated as the difference between the values measured on scout view and the real phantom size. Second, a model was developed investigating the relationship between the dimensions of the object, its image, and the table height. This relationship was tested on our data.ResultsScout view measurements were precise, with less than 0.53% difference between readers. In addition, small biases of about 1 mm were detected in the z-axis, whatever the table height. In the other axes, serious biases from −13 to +73 mm were measured. Furthermore, at isocentre, overestimations up to 7 mm were shown. The results also indicated that biases in scout view measurements are because of the geometrical projection related to the object-detector distance.ConclusionsMeasurements in the table movement axis are precise and accurate, conferring to scout views an added value for preoperative planning in orthopedic surgery.  相似文献   
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A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling.  相似文献   
4.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。  相似文献   
5.
目的:探讨改进的内外括约肌在原位肛门整形重建术中的应用及其手术效果。方法:改进包括:①肛门内括约肌改进为双层双环肌套;②肛门外括约肌改进为股薄肌采用“围巾式”环绕结肠末端一周,其远端剖为两条,一条缝合固定于耻骨韧带;另一条缝合固定于骶尾韧带,即为肛门外括约肌重建和外括约肌浅部和深部的重建。结果:38例术后肛门外形及功能和远期生活质量、生存率均更为满意。术后随访总优良率达94.73%;远期生存率达76.32%。结论:低位直肠癌Miles术后,同时行改进的内外括约肌原位肛门整形重建的效果是可行的,更接近正常的肛门解剖结构和生理功能。  相似文献   
6.
Posterior dislocations of the sternoclavicular joint are uncommon, but are potentially quite serious. Radiologic diagnosis and management are frequently difficult. The specialized projections available are not widely known, and the role of plain films is poorly understood. The incidence, pathomechanics, and clinical manifestations of such dislocations are presented and the radiologic diagnosis is discussed.  相似文献   
7.
From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained.  相似文献   
8.
There is an ongoing debate in nurse education concerning the role and delivery of the biological sciences in the nursing curriculum. One of the fundamental questions raised by this debate asks how best can teachers impart biological knowledge in a manner that can be readily applied by students and qualified nurses to inform their clinical practice. This paper will include a discussion of some of the features of pre-registration education that may have influenced the manner in which biological sciences are perceived, taught and used by nurses. It will be argued that nursing may have developed a form of incomplete holism and that this may be in part responsible for the challenges that remain to be met within this area of the nursing curriculum. As a response to incomplete holism an innovative approach within pre-registration education will be introduced. This development involves the use of linked teaching sessions which aim to develop the analytical skills necessary to apply physiological knowledge to nursing practice.  相似文献   
9.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts.  相似文献   
10.
We present the construction of a homogeneous phantom to be used in simulating the scattering and absorption of X-rays by a standard patient chest and skull when irradiated laterally. This phantom consisted of lucite and aluminium plates with their thickness determined by a tomographic exploratory method applied to the anthropomorphic phantom. Using this phantom, an optimized radiographic technique was established for chest and skull of standard sized patient in lateral view. Images generated with this optimized technique demonstrated improved image quality and reduced radiation doses.  相似文献   
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