成人股骨头缺血坏死直接数字化X线射影与磁共振成像影像表现分析

成人股骨头缺血坏死（avascular necrosis of the femoral head,ANFH）是临床较常见的髋关节疾病,是由于多种原因导致的股骨头局部血运不良,引起骨细胞进一步缺血、坏死、骨小梁断裂、股骨头塌陷的一种病变,随着病情的发展,股骨头发生塌陷,髋关节功能减退甚至丧失,严重影响患者的生活质量. 现将我院2014年7月至2016年6月的61例有完整资料的成人股骨头缺血坏死患者的直接数字化X线射影（DR）及磁共振成像（MRI）表现进行分析总结.

分析成人股骨头缺血坏死直接数字化X线射影与磁共振成像影像表现

目的:分析成人股骨头缺血坏死(ANFH)直接数字化X线射影与磁共振成像(MRI)影像表现。方法:研究我院收治的股骨头缺血坏死患者56例,筛入患者均接受MRI影像技术与数字化X线射影检查,对其临床资料进行回顾性分析。结果:采用MRI诊断检查出72个,检出率为100%,而X线诊断检出共49个,检出率为68.06%。结论:研究显示,ANFH早期影像学表现为骨髓水肿,相比于数字化X线射影技术,MRI是早期诊断ANFH最有效、敏感性最高的方法。

腰椎休门病的直接数字化X线射影CT诊断价值

腰椎休门病多见于青少年男性，患者主要症状为不伴根性疼痛的下腰部疼痛，无临床上的脊柱畸形。其临床表现、影像学表现与传统意义上的休门病均有较大的差异。临床医生易误诊为感染、陈旧性骨折、肿瘤等病变而采取不必要的治疗口，给患者及家属带来不必要的经济和心理负担。1985年Green等四首次描述本病，1987年Blumenthal等It]明确提出腰椎休门氏病的概念并建议对其进行初步分型。现结合文献对15例腰椎休门病的直接数字化X线射影（DR）、CT表现进行回顾性分析，旨在提高对本病的认识，减少误诊。

Projection registration of X-ray image and CT image

A methodology for alignment of an X-ray image and a CT image, based on the Chamfer 3-4 distance transform and simulated annealing optimization algorithm is presented. Firstly, an initial transformation matrix is constructed. For the convenience of computing, geometric models of the X-ray device to reconstruct the calibration matrix are used. Then, by defining the distance between the 3-D protective and the 2-D object image, we optimize this distance matching problem, using the simulated annealing algorithm. This method is also integrated into medical intra-operation, dealing with the data set acquired from 3-D image workstation and active navigation.

Soil Macropore Structure Characterized by X-Ray Computed Tomography

Undisturbed soil core with many macropores and disturbed soil core with onlyone macropore (diameter is 10 mm) were probed by X-ray computed tomography (CT). The size, number,shape and continuity of macropores in the transverse and vertical sectionsof soil were characterizedusing CT scanning images. The probability densities of macropores in the transverse section of soilcore exhibited a logarithmic P distribution. Results indicated that CT scanning was a promisingnondestructive method for characterizing macropores in soils.

THE REAL IN TIME CT MONITORING OF THE MESO-DAMAGE EVOLUTION LAW OF SANDSTONE UNDER TRIAXIAL COMPRESSION

The real in time computerized tomography (CT) testing of the meso damage propagation law of the whole sandstone failure process under triaxial compression has been completed using the newest specified triaxial loading equipment corresponding to the CT machine. Through the CT scanning, the clear CT images which include from the microcracks compressed stage to growth stage, bifurcation stage, development stage, crack fracture stage,the rock sample failure until to unloading stage in the different stress states were obtained. The CT values, CT images and the other data have been analyzed. Based on the results of the CT testing of meso damage evolution law of rock,the stress threshold value of meso damage of rock is given, and the stress strain complete process curve of rock is divided into some sections. The initial rock damage propagation law is given in this paper.

Magnetic Resonance Urography and X-ray Urography Findings of Congenital Megaureter

Objective To observe the imaging findings of congenital megaureter in order to enhance the understanding of this disease. Methods Image data of 5 patients with congenital megaureter and 2 misdiagnosed patients were analyzed, and image findings of congenital megaureter were summarized. Elscint Prestig 2.0T superconductive magnetic resonance urography （MRLI） with conventional sequence （spin-echo, T 1W1560 ms/16 ms; fast spin-echo, T2WI 9600 ms/96 ms） was performed. Raw data were acquired with fast spin-echo sequence from heavy T2-weighted image （9600 ms/120 ms）. Post-processing method of MRH was the maximum in- tensity projection with three-dimensional reconstruction in the workstation. Intravenous pyelography （IVP） was conducted, in which X-ray films were taken 7 minutes, 15 minutes, and 30 minutes after injecting contrast agent, except that in 2 patients the films were taken delayed at 60 and 90 minutes. X-ray retrograde pyelography was performed on 2 patients, successful in one but failed in the other. Results The dilated ureter showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in conventional MRI. The mass wall was intact, uniform in thickness, and showing hy- pointensity on Tl-weighted and T2-weighted images. The MRH images showed a retroperitoneal mass appearing as an elongated tubular cystic structure spreading from kidney to bladder. MRLI also revealed dilated calices and renal pelvis, pelviureteric obstruction, and renal duplication. The main signs of congenital megaureter in X-urography was significant dilatation of ureter, or normal renal pelvis with ureter dilatation, hydronephrosis, deformity, and displacement. Conclusions MRH with X-urography could visualize the characteristics of congenital megaureter, including the dilation of renal pelvis and ureter, calculi, urinary tract duplication, and stenosis location. The two techniques can complement each other in disease diagnosis and provide more detailed information for preoperative treatment.

Treatment of Non-Small Cell Lung Cancer (NSCLC) Using CT in Combination with a PET Examination to Minimize the Clinical Target Volume of the Mediastinum

OBJECTIVE To decrease radiation injury of the esophagus and lungs by utilizing a CT scan in combination with PET tumor imaging in order to minimize the clinical target area of locally advanced non-small cell lung can-cer, without preventive radiation on the lymphatic drainage area. METHODS Of 76 patients with locally advanced non-small cell lung cancer (NSCLC), 32 received a PET examination before radiotherapy. Preventive radiation was not conducted in the mediastinum area without lymphatic metastasis, which was confirmed by CT and PET. For the other 44 patients, preventive radiation was performed in the lymphatic drainage area. PET examinations showed that the clinical target volume of the patients was decreased on average to about one third. The radiation therapy for patients of the two groups was the same, i.e. the dose for accelerated fractionated irradiation was 3 Gy/time and 5 time/week. The preventive dose was 42 to 45 Gy/time, 14 to 15 time/week, with 3-week treatment, and the therapeu- tic dose was 60 to 63 Gy/time, 20 to 21 time/week, with a period of 4 to 5 weeks. RESULTS The rate of missed lymph nodes beyond the irradiation field was 6.3% and 4.5% respectively in the group with and without PET exami- nation (P = 0.831). The incidence of acute radioactive esophagitis was 15.6 % and 45.5% in the two groups respectively (P = 0.006). The incidence of acute radiation pneumonia and long-term pulmonary fibrosis in the two groups was 6.3% and 9.1%, and 68.8% and 75.0%, respectively (P = 0.982 and P = 0.547). CONCLUSION The recurrence rate in the lymph nodes beyond the tar-get area was not increased after minimizing the clinical target volume (CTV), whereas radioactive injury to the lungs and esophageal injury was reduced, and especially with a significant decrease in the rate of acute radioactive esophagitis. The method of CT in combination with PET for minimizing the mediastinal CTV is superior to the conventional preventive radiation of the mediastinum.

Studies of Microstructure of Kernels of Macadamia integrifolia and Its Hybrids through MRI, X-Ray Tomography and Confocal Microscopy

The aim of this study was to apply the existing techniques that enable examination ofmacadamia kernels to provide a better understanding of physico-chemical properties of kernels during postharvest processing. These techniques, such as X-ray tomography, could be applied for quality monitoring in the macadamia industry. The objectives of this study were to investigate the browning centre symptoms that usually occur in macadamia nuts-in-shell. The applied techniques included confocal microscopy, X-ray tomography and magnetic resonance imaging （MRI）. Five different varieties of macadamia nuts （A38, 246, 816, 842 and Daddow） were selected to include distinct characteristics, such as drop pattern and growing location. Analysis of the microstructure of kernels by confocal microscopy showed the distribution of possible brown pigment compounds as well as the distribution of lipids, carbohydrates and proteins inside macadamia cells. Physical properties data, including shell density and seed to volume ratio, were obtained by X-ray tomography. Magnetic resonance diffusion tensor imaging used in this study showed marked differences in microstructure which indicate that different varieties exhibit different microstructures expressed as fraction ofanisotropy and apparent diffusion coefficient that appear to be related to the occurrence of the brown centre. Hence, the findings of this study have potential to improve the existing postharvest techniques used in the macadamia processing industry. They will be of benefit to the industry in terms of improved quality control and cost reduction.

高分辨率CT检查在以肠梗阻为主要表现急性阑尾炎诊断中的应用

目的探讨高分辨率CT(HRCT)检查在以肠梗阻为主要表现急性阑尾炎诊断中的应用效能。方法对30例临床疑似以肠梗阻为主要表现急性阑尾炎患者的腹部HRCT图像和腹部X线透视(或者腹部X线平片)结果进行分析,并与手术、病理结果作比较。结果30例患者中,手术、病理诊断为急性阑尾炎引起机械性小肠梗阻者19例(1例急性单纯性阑尾炎、17例急性化脓性阑尾炎、1例急性坏疽性阑尾炎),非阑尾炎源性肠梗阻者11例。以手术、病理结果为金标准,HRCT检查诊断以肠梗阻为主要表现的急性阑尾炎真阳性18例、假阳性1例、真阴性10例、假阴性1例,诊断敏感性为94.74%、特异性为90.91%、准确率为93.33%、阳性预测值为94.74%、阴性预测值为90.91%;X线检查诊断以肠梗阻为主要表现的急性阑尾炎真阳性4例、假阳性2例、真阴性9例、假阴性15例,诊断敏感性为21.05%、特异性为81.82%、准确率为43.33%、阳性预测值为66.67%、阴性预测值为37.50%;HRCT、X线检查诊断以肠梗阻为主要表现急性阑尾炎的敏感性、特异性、准确率、阳性预测值、阴性预测值相比,χ2值分别为18.24、0.39、17.33、1.26、8.67,P值分别<0.05、>0.05、<0.05、>0.05、<0.05。结论HRCT检查对以肠梗阻为主要表现急性阑尾炎诊断具有较高的准确率,而且明显高于X线检查的诊断准确率。

胚胎型横纹肌肉瘤的影像学表现

目的探讨胚胎型横纹肌肉瘤(ERMS)的CT和MRI表现。方法回顾性分析经病理证实的26例ERMS的临床及影像学资料。结果 14例鼻部ERMS中,邻近骨质破坏11例,眼眶受累5例,翼腭窝及颅内侵犯各4例;5例腹盆腔及腹膜后ERMS中,3例包绕邻近大血管,2例腹膜种植转移;5例肌肉及肌间隙ERMS病变较局限,其中2例伴邻近骨质轻微破坏;1例ERMS位于左颌下腺区;1例ERMS为颅骨多发病灶。16例患者有区域淋巴结转移,5例呈环线状强化。结论 ERMS的临床及影像学表现缺乏特异性,对患者年龄、发生部位、强化方式、邻近骨质的破坏及区域淋巴结转移等进行综合分析有助于治疗前诊断。

多层螺旋CT灌注成像对重症急性胰腺炎的临床应用研究

目的:探讨多层螺旋CT灌注成像对重症急性胰腺炎的诊断价值。方法:使用16排螺旋CT对9例重症急性胰腺炎患者(SAP)和17例轻症急性胰腺炎(MAP)以及41例正常胰腺组进行CT灌注扫描。应用perfusion3软件包进行数据处理,计算各组的血流量(BF)、血容量(BV)、平均通过时间(MTT)、毛细血管通透性(PS)等灌注参数,对各组样本灌注数据的均数及标准差进行单因素方差分析。对急性胰腺炎临床生化指标与灌注参数BF变量之间进行相关性检验。结果:MAP、SAP的BF、BV平均值较正常胰腺组显著降低(P<0.01),PS高于正常组(P<0.05),MAP组的BF、BV显著高于SAP组。结论:CT灌注成像技术对急性胰腺炎的诊断和指导临床治疗具有重要意义。

126例新生儿肺炎的临床分析

目的总结新生儿肺炎临床表现、病原学及X线表现,以便早期诊断,指导临床选择抗生素。方法对126例新生儿肺炎的临床表现、病原学及X线资料进行分析。结果 (1)新生儿肺炎临床表现多样化、不典型,年龄越小症状体征越不明显;(2)由于受年龄小等因素的限制,新生儿肺炎病原学诊断困难,且有假阳性,容易导致过度治疗或漏诊;(3)胸部X线检查是诊断新生儿肺炎不可少的手段。结论新生儿肺炎的临床表现及肺部体征不典型,需结合临床表现、肺部体征、微生物学检查及胸部X线检查结果,及早诊断并合理选用抗生素,避免滥用抗生素,预防细菌耐药性的增加。

小儿肺门影增大辨识的Kappa一致性分析

目的研究不同影像医师对小儿＂肺门影增大＂征象辨识的个体间差异,分析临床工作中对该征象辨识的稳定性。方法 3位不同工作经历的影像医师作为观察者,对60例患儿的胸部DR胶片进行评价,确定小儿肺门影增大的有无及其程度。结果 3位观察者在对肺门等级评判上存在一定差异,但总体评判上差异无统计学意义（P〉0.05）。Kappa检验结果显示,对肺门＂正常＂的评判K值0.427~0.643（P〈0.05）;对＂轻度增大＂的评判K值0.531~0.617（P〈0.05）;对＂明显增大＂的评判K值0.786~0.844（P〈0.05）。结论小儿肺门影增大等级主观判断个体之间存在差异,其中对＂正常＂＂轻度增大＂的评判一致性较差,对＂明显增大＂的评判一致性较好。

64例原发性肝癌的螺旋CT检查结果分析

目的观察原发性肝癌在螺旋CT扫描图像上的特征。方法对64例原发性肝癌患者的螺旋CT扫描结果进行分析。结果64例患者螺旋CT扫描均确诊为肝癌,共发现病灶95个,其中平扫期发现45个(密度均匀15个、不均匀23个、高密度7个)、肝动脉期扫描发现70个(均匀性高密度强化26个、中心低密度强化32个、低密度无明显强化12个)、门静脉期扫描发现80个(低密度70个、等密度6个、高密度4个)。结论螺旋CT在增强扫描的不同时期能够显示不同密度的肝癌病灶。

DR的图像质量控制与影响因素

目的探讨数字化X线射影(DR)图像质量控制方法及其影响因素。方法选择放射线科200张非甲级DR片实施回顾性分析,总结影响质量的因素,并制定合理的图像质量控制方案。结果影响DR图像质量的因素主要有摄片技术参数、量子噪声、X线机器工作性能、图像后处理技术及激光相机等。结论 DR图像质量影响因素多因人为所致,为此应不断提高操作人员技术,促使他们严格按照X线摄影技术要求与规范执行。

DR系统偏差校正

X射线照射野、实际X射线束和平板探测器如存在偏差,就会造成平板探测器接收的X线信号出现偏差,影响影像质量。本文重点讨论X射线束、X射线照射野、平板探测器三者之间的关系,解决光野指示与X射线区域的偏差柆正、X射线束与平板探测器的垂直调整、X射线照射野和图像接收组件中心调整。

NON-INVASIVE IMAGING OF CORONARY ARTERY WITH 16-SLICE SPIRAL COMPUTED TOMOGRAPHY

To evaluate the value of 16-slice spiral CT in the demonstration of coronary artery and in the diagnose of coronary artery stenosis. Methods Plain and enhanced CT scans were performed with a 16-slice CT scanner (Sensation 16, Siemens, Germany) in 230 patients with suspected coronary heart disease (CHD). Parameters of the plain scan were: 120 kV, 133 mA, slice col-limation 16 mm×1.5 mm, rotation time 0.42 seconds, increment 1.5 mm, and slice width 3 mm. Parameters of the enhanced scan were: 120 kV, 500 mA, slice collimation 16 mm×0.75 mm, rotation time 0.42 seconds, increment 0.5 mm, and slice width 1 mm. Enhanced CT scan was performed with a rapid intravenous injection of 100 mL iothalamate meglumine (Ultravist) (370 mgI/mL) or Omnipaque (350 mgI/mL) and 30 mL 0.9% NaCl chaser bolus at a flow rate of 3.5 mL/s. Calcium scoring with plain scan images and two and three dimensional reconstruction with enhanced scan images were made in all cases, among which 30 cases underwent conventional coronary angiography. Demonstration of coronary arteries and their stenosis were evaluated and the factors that might influence the image quality were analyzed. Results Coronary calcium scores were calculated and coronary artery was demonstrated in our study. In the evaluationof image quality with volume rendering technique (VRT) images, 78.3% of the images were of the first class, 12.2% the sec-ond class, and 9.6% the third class. Multi-planar reconstruction (MPR) and maximal intensity projection (MIP) were better than VRT in the demonstration of small branches. The image quality was related to the heart rate, with or without arrhythmia, and breath-hold ability of patients. Comparative study of the stenosis of coronary arteries in 30 cases showed that the sensi-tivity and specificity of 16-slice coronary CT angiography (CTA) to diagnose significant stenosis were 95.8% and 94.8% resp-ectively. Conclusion As a non-invasive and quick method, 16-slice coronary CTA is sensitive and specific to diagnose the stenosis of coronary arteries and can be used as a screening method in the diagnosis of CHD.

Volumetric fraction measurement in oil-water-gas multiphase flow with dual energy gamma-ray system

Volumetric fraction distribution measurement is a constituent part of process tomography system in oil-water-gas multiphase flow. With the technological development of nuclear radial inspection, dual-energy γ-ray techniques make it possible to investigate the concentration of the different components on the cross-section of oil-water-gas multiphase pipe-flow. The dual-energy gamma-ray technique is based on materials attenuation coefficients measurement comprised of two radioactive isotopes of 241Am and 241Cs which have emission energies at 59.5 keV and 662 keV in this project. Nuclear instruments and data acquisition system were designed to measure the material’s attenuation dose rate and a number of static tests were conducted at the Multiphase Laboratory, Institute of Mechanics, Chinese Academy of Sciences. Three phases of oil-water-gas media were inves- tigated for their possible use to simulate different media volumetric fraction distributions in experimental vessels. Attenuation intensities were measured, and the arithmetic of linear attenuation coefficients and the equations of volumetric fractions were studied. Investigation of an unexpected measurement error from attenuation equations revealed that a modified arithmetic was involved and finally the system achieved acceptable accuracy in experimental research.