数字化立位全脊柱成像技术的研究

目的　探讨数字化立位全脊柱的成像技术。方法　在数字化X线设备上 ,分次采集全脊柱的影像数据 ,获得 2 2例受检者的正、侧位原图共 88幅 ,经图像工作站合成为 4 4张数字化全脊柱影像。选择同一体位的胸、腰椎片为配对组 ,测量每组图像的水平位移长度 ,分析其对脊柱侧凸角(Cobb角 )的影响。结果　每一配对组的胸、腰椎影像移位差异无显著性意义 (t =0 0 8～ 1 0 1,P >0 0 5 )。椎体移位每递增 1 7cm ,人体倾角 (α)发生± 1°的变化 ,对Cobb角影响极小 ,可以忽略不计。结论　在图像工作站实现数字化全脊柱的成像技术 ,对普及脊柱侧凸检查具有很好的推广应用价值。     

全下肢负重立位DR成像技术的探讨

近年来,直接数字化成像设备(direct radiography,DR)以其较大的曝光宽容度,能进行多种后处理、而且无须胶片,存储、传输方便,并大大减少技术人员的工作量等优点迅速成为了各家大医院放射科主要的影像设备。例如骨科开展的下肢髋关节、膝关节和踝关节置换就需要拍摄全下肢负重     

DWIBS和全脊柱MR成像对脊柱恶性肿瘤的诊断研究

目的 探讨磁共振背景抑制弥散加权成像(DWIBS)在脊柱恶性肿瘤早期诊断中临床应用价值.方法 60例临床证实为恶性肿瘤患者行全身弥散加权成像检查,并于同一时间对可疑部位行常规磁共振成像检查,必要时增强扫描,诊断结果与临床综合评价结果进行比较,分别比较DWIBS和常规磁共振成像所显示的病例数.结果 60例患者中55例经临床综合评价为脊柱转移瘤.常规MRI联合DWIBS检查的敏感性、特异性、阳性预测值、阴性预测值分别为98.8％、99.4％、95.4％、99.8％.与常规MRI及DWIBS比较,P＜0.05有统计学意义.结论 DWIBS在恶性肿瘤脊柱转移瘤早期诊断中具有一定的应用价值,结合常规MRI检查可进一步明确诊断.     

MRI全脊柱成像技术及其应用价值研究

近年来,随着磁共振多通道、Tim技术的发展,不仅可行大范围MR全脊柱成像,而且可以得到高分辨率的局部图像。现将临床应用报道如下。1材料与方法1.1临床资料77例可疑颈、胸、腰椎或脊髓疾病患者行MRI全脊柱成像,其中男45例,女32例,年龄6~79岁,平均年龄51岁。1.2设备仪器采用西门子Avanto 1.5T超导磁共振成像系统,全脊柱成像软件、自动移床技术,脊柱矩阵线圈、头颅矩阵线圈、颈部矩阵线圈和两个体部矩阵线圈。1.3检查方法嘱患者仰卧在检查床上,脊柱自然平伸,极少数严重的病理疼痛患者可在检查前口服或静脉注射镇痛剂。采用二步法(二步连接…     

全下肢及全脊柱成像技术的临床应用

目的:探讨全下肢及全脊柱成像技术的临床应用。方法:介绍该技术成像的过程,并对已完成的200例检查结果与一般成像技术进行对比分析。结果:200例中,全下肢或/和全脊柱成像成功拼接180例,20例失败。拼接成功者,能清晰及正确显示骨关节结构,从而达到临床诊断和治疗要求。结论:全下肢及全脊柱成像技术具有普遍推广应用价值。     

CR全脊柱数字化成像技术的应用与比较

脊柱侧凸的常规检查方法是全脊柱X线正、侧位摄片,来反映脊柱侧凸畸形的状况。脊柱侧凸的X线检查要求每张脊柱正、侧位片,包含上自颈椎和双侧肩部,下至骨盆和髋关节在内的全脊柱,可以反映畸形的真实面貌和平衡情况。一张拼接好的X线片对青少年特发性脊柱侧凸进行手术前评估和脊柱侧凸三维矫形的预测有重要意义[1]。以前多采用超长感绿X线胶片(30 cm×61 cm)一次曝光[2];后采用多块IP板一次曝光,并将图像在计算机内进行拼接,但其拼接密度的均匀性和准确性不太理想。本院引进富士CR超长IP板,进行全脊柱一次曝光摄片。笔者就多块IP板一次…     

全脊柱DR与CR成像质量的对比分析

目的 探讨直接数字X线摄影(DR)在立位脊柱全长摄片中的应用.方法 177例患者按就诊时间先后分2组分别使用CR和DR技术拍摄全脊柱正侧位片,由放射科经验丰富的医师技师各2名对所有全脊柱影像进行评析.结果 (1)DR摄影成像的密度对比优于CR.(2)DR图像的拼接成功率低于CR.结论 使用DR进行全脊柱摄片,图像质量优于CR摄片.     

数字合成X线体层成像实验研究

数字合成X线体层成像(digital tomosynthesis)是在传统体层摄影的几何原理基础上,结合现代数字图像处理技术开发的新型体层成像方法.国外近期有初步临床应用方面的报道[1-2].笔者对数字合成体层成像的原理和相关算法进行了研究,在传统体层摄影设备上采集实验模体的多角度投影数据,然后编程实现任意高度层面(平行于探测器)图像的合成,并与传统体层摄影图像在辐射剂量和图像质量方面进行了初步比较.     

数字X线成像技术的进展

数字化技术正给医学影像领域带来革命性的变化。对X线成像的数字化,从CR、DR、数字钼靶摄片,到DSA技术,都正在经历从发展到成熟应用于临床的过程。本文阐述了数字化X线成像技术的分类,对CR和DR技术的最新进展、乳腺数字成像,进行了较为详细的论述,综述了最新的技术进展和临床应用发展。     

Optimization of X-ray conditions for full spine X-ray examinations in slot-scan digital radiography

The purpose of this study was to optimize X-ray conditions for full spine X-ray examinations in slot-scan digital radiography (SSDR). Follow-up of spinal deformities, such as scoliosis, typically involves many radiographs of the patient throughout childhood and adolescence. The Radiation doses for the full spine X-ray examination should be minimized. Recently, SSDR has been introduced for full spine as well as lower extremity examinations. This system utilizes slot scanning geometry to acquire the radiographic images. X-ray energy characteristics of direct amorphous Selenium (a-Se) digital fluoroscopy and short time X-ray tube loads of this system were investigated. Orthopedists evaluated the irradiation time for full spine radiographs in various conditions using an observer study. Patient doses were measured with radiophotoluminescence glass dosimeters, which were implanted in various tissue and organ positions within an anthropomorphic phantom. In the optimization of conditions for SSDR, patient doses are reduced by approximately 60% compared to default setting.     

Medical physics: some recollections in diagnostic X-ray imaging and therapeutic radiology

Medical physics has changed dramatically since 1895. There was a period of slow evolutionary change during the first 70 years after Roentgen's discovery of x rays. With the advent of the computer, however, both diagnostic and therapeutic radiology have undergone rapid growth and changes. Technologic advances such as computed tomography and magnetic resonance imaging in diagnostic imaging and three-dimensional treatment planning systems, stereotactic radiosurgery, and intensity modulated radiation therapy in radiation oncology have resulted in substantial changes in medical physics. These advances have improved diagnostic imaging and radiation therapy while expanding the need for better educated and experienced medical physics staff.     

A study and optimization of lumbar spine X-ray imaging systems

A Monte Carlo program has been developed that incorporates a voxel phantom of an adult patient in a model of the complete X-ray imaging system, including the anti-scatter grid and screen-film receptor. This allows the realistic estimation of patient dose and the corresponding image (optical density map) for a wide range of equipment configurations. This paper focuses on the application of the program to lumbar spine anteroposterior and lateral screen-film examinations. The program has been applied to study the variation of physical image quality measures and effective dose for changing system parameters such as tube voltage, grid design and screen-film system speed. These variations form the basis for optimization of these system parameters. In our approach to optimization, the best systems are those that can match (or come close to) the calculated image quality measure of systems preferred in a recent European clinical trial, but with lower patient dose. The largest dose savings found were 21% for a 400 speed class system with a grid having a strip density of 40 cm(-1) and a grid ratio of 16. A further dose saving of 13% was possible when a 600 speed class system was employed. The best systems found from the optimization correspond to those recommended by the European Commission guidelines on image quality criteria for diagnostic radiographic images.     

全脊柱摄影在儿童进行性肌营养不良中的应用探讨

目的研究儿童进行性肌营养不良与脊柱侧弯的关系。方法选取89例进行性肌营养不良患儿作为研究对象,所有患儿均行全脊柱正侧位X线摄影,分析所有患儿的脊柱侧弯情况。结果 89例进行性肌营养不良患儿中61例有不同程度的脊柱侧弯,侧弯比率为69%。结论进行性肌营养不良与脊柱侧弯的发病有关,儿童患进行性肌营养不良易引发脊柱侧弯,应当引起重视,早发现早治疗。     

Casualty radiology with lightweight X-ray machine.

A small lightweight X-ray machine is needed for use in military medicine for humanitarian service missions, training exercises, and even tactical situations. In such circumstances, the large size and great weight of conventional X-ray equipment limit its use and make this diagnostic modality unsuitable. I have used a small lightweight X-ray machine and obtained adequate X-ray exams in a high percentage of patients.     

Anatomy and radiology of the sellar spine

Summary Five anatomical and radiological observations of a spine protruding into the pituitary fossa are reported. This osseous spine, about 4 mm long, arises in the midline from the inferior part of the anterior aspect of the dorsum sellae and extends upward and forward. The possible origins of this malformation are discussed.     

X-ray field collimation in diagnostic radiology

A comprehensive study of radiographic practice within radiodiagnostic departments throughout Wales is currently being carried out under the auspices of the College of Radiographers and the Royal College of Radiologists. This paper reports on collimation practices observed in more than 2000 individual patient radiographs involving seven types of examination. Film dimensions are compared to those of the X-ray field and the unnecessary irradiation of radiosensitive organs consequent upon inappropriate collimation is considered. The suitability of film sizes frequently chosen for particular projections is also examined.     

Digital subtraction angiography in interventional radiology

Intraarterial digital subtraction angiography (DSA) was used an an adjunct to interventional vascular procedures (embolotherapy and transluminal angioplasty) in 56 patients. The advantages of intraarterial DSA include improved contrast resolution, instantaneous subtraction capability, and immediate image availability. A considerable reduction in contrast dose and concentration, procedure time, and patient discomfort can be expected when interventional vascular procedures are performed with the assistance of intraarterial DSA.