直接数字化X线摄影在鼻骨摄影中的应用

目的探讨直接数字化X线摄影（direct digitized radiography，DDR）在鼻骨摄影中的应用价值。方法对100例DDR鼻骨侧位影像采用图像后处理方法中多级图像对比增益法，又称“交响乐”功能（muhi-scale image contrast amplification，MUSICA）、影像切割与局部放大等功能进行后处理，同时数字随机法对其中30例行普通X线摄影。由放射科经验丰富的医、技师各2名对所有鼻骨影像进行分析，评价其对鼻骨骨折、鼻骨整体及鼻周软组织的显示。结果100例DDR鼻骨影像中，诊断骨折46例，鼻骨整体及鼻周软组织显示满意的分别为95和92例；对照组30例DDR鼻骨影像发现骨折18例，X线片发现骨折11例，漏诊7例（x^2=5，14，P〈0，05），30例DDR影像中，鼻骨整体及鼻周软组织显示满意的均为28例；普通X线片两者显示满意的分别为6例（x^2=20．05，P〈0．05）和10例（x^2=15．06，P〈0．05）。结论DDR影像比普通X线影像能更好的显示鼻骨和鼻周软组织，提高鼻骨骨折的检出率。     

新生儿胸部摄影适宜照射野面积与吸收剂量的探讨

目的:探讨适宜新生儿胸部摄影的照射野面积及中心线、照射野外各腺体表面的平均吸收剂量。方法:以新生儿尸体为体模、依西门子点数法设计四种照射野,每野112组曝光条件。感光效应E值不变,改变照射野面积及曝光点数,通过448次预采样,分析照射野面积与平均吸收剂量的关系。结果:照射野面积为10cm×12.5cm,9点曝光组的平均吸收剂量最小。结论:适宜新生儿胸部摄影的最大照射野面积为10cm×12.5cm;恰当的曝光条件组合为9点组;允许的平均吸收剂量中心线为≤49.88μGy,未加防护时照射野外的性腺为≤0.070μGy、甲状腺为≤35.9μGy、晶体为≤0.062μGy。     

照射野与照片质量和防护的匹配

照射野是X线束入射于肢体的曝光面的大小；是由带光学准直仪遮线器调控，它可随意调节照射野的大小，使用方便。近年来，国内外生产的X线机大部装有这种设备：另外，还有自动束光器，采用多重叶片结构，功能较多，透视照射野大小能自动地限定在受像器(荧光屏或影像增强器)或所选用遮光板的可见区域，有胶片尺码探测器，自动记忆胶片大小规格，摄影照射野将按照胶片大小(或所选用的遮光板)准直，摄影后能自动恢复到先前的透视照射野。焦点与受像器的距离变化时，叶片开口也随之改变，保持着设定照射野大小不变。     

曝光条件、IP尺寸等与CR照片影像的空间分辨力

目的：探讨曝光条件、IP尺寸等与CR照片影像空间分辨力的关系。方法：依据Siemens点数法曝光条件表，在点数不变的情况下换算出摄影部位手的数组曝光条件，选用四种不同尺寸的IP及大小焦点，分别对矩形波测试卡进行摄影。采用无放大和放大2倍的后处理技术，视读并记录CR照片影像的空间分辨力数值，分析其影响CR照片影像空间分辨力的条件。结果：①摄影部位、曝光条件相同，CR照片影像的空间分辨力，小焦点大于大焦点；②摄影部位、曝光条件及焦点大小相同，CR照片影像的空间分辨力随IP尺寸的增加而减小；③CR照片影像的空间分辨力，放大2倍的照片影像明显高于无放大处理的照片影像；④适宜的曝光条件可提高CR照片影像的空间分辨力。结论：影响CR照片影像空间分辨力的条件：小尺寸IP大于大尺寸IP；小焦点大于大焦点；适宜的后处理放大倍数大于无放大处理；适宜的曝光条件组合大于其它组合。     

DR系统中平板探测器能量响应特性的研究

目的 研究平板探测器(FPD)对kV、mAs的响应特性。方法使用HOLOGIC公司生产的DR系统，变换摄影条件，通过系统软件功能测出设定各点的原始灰度值，通过比较发现其变化规律，为摄影条件的选择提供指导。结果在100kV内，影像的原始灰度值随着kV值的增加而近乎呈线性增加，而大于100kV后，影像的灰度值随着kV增加而增加的幅度明显下降；FPD对mA和曝光时间的响应特性几近线性。结论胸部数字X射线摄影的最佳kV值在100kV左右。在kV满足穿透力的前提下，不要只通过增加kV值来提高影像的灰度值(高kV摄影除外)；要配合mA和曝光时间的变化来增加或降低影像的灰度值，合理化选择摄影条件的搭配，避免不必要的辐射损伤。     

X线机房内射线空间分布及合理利用的实验研究

目的：探讨 X 线机房内辐射场分布情况,为危重患者、陪护人员和需要进入机房施救的医务工作者提供科学的辐射防护依据。方法以 X 线管为中心,在摄影床水平面选择不同的点放置热释光剂量计(TLDs),改变 X 线摄影技术参数中的 X 线管电压值(kV)和照射野(FOV),选定不同的实验条件分组曝光,将受照射后的热释光剂量计送到实验室测量,所测数据均扣除本底。结果对每组实验数据中方位和距离2个变量进行单因素方差分析,P 值均<0.01,差异有统计学意义。相同 X 线摄影条件下,距离 X 线管中心越远,辐射剂量值越低,距离 X 线管中心越近辐射剂量值越高,10 cm 处的剂量值最高,距离 X 线管中心120 cm 处的剂量值最低;相同摄影条件和距离,辐射场剂量值在机房 X 线管阳极侧相对较低,辐射场剂量值在 X 线管后方相对较高;相同管电压值、相同距离和方位,FOV 为52.6 cm×52.6 cm 比 FOV 为34 cm×34 cm 条件下的辐射场剂量值较高;相同 FOV、相同距离和方位,120 kV 比70 kV 条件下的辐射场剂量值较高。结论X 线机房内医护及陪护人员的位置应尽量选择右侧方向(阳极),远离X 线管中心,避开 X 线管后方和阴极方向,可明显降低受照辐射剂量。     

计算机X射线摄影系统与屏-片系统能量响应的对照研究

目的探讨计算机X射线摄影(CR)影像像素值与曝光因子(kVp和mAs)、被照体厚度的关系，传统屏-片系统照片密度与曝光因子、被照体厚度的关系，并对两种能量响应的关系进行比较，为使用CR影像像素值和成像板(IP)平均入射照射量的测量值作为自动曝光控制系统的设定参数提供依据。方法厚度为10、15、20cm的丙烯树脂板分别在50～90、70～120、90～140kVp和密度档为-2时成像，对照屏-片系统与CR系统在不同管电压、相同被照体和密度档时的自动曝光响应。以上测试都使用滤线栅，用电离室测量IP的入射照射量。结果在获得满足临床诊断要求的情况下，CR所需曝光量大约是高速屏-片系统的2倍。CR系统的管电压像素值关系曲线与管电压照射量曲线相同。10cm被照体时，50～90kVp间的照片密度差值为1．21，像素差值为270；而20cm被照体时，90～130kVp间的密度差值为0．30，像素差值为100；15cm被照体时密度和像素差值居于两者之间，分别为0．62和160。结论Kodak CR900系统的感度值与中速屏-片系统的感度比较接近。均匀野影像的曝光指示器值EI和IP照射量测量值可以用来设定自动曝光控制系统的光电计时器。屏-片系统照片密度和CR影像像素值随kVp变化的规律以及两者的差异，对自动曝光控制系统的校准起参照作用。     

变野式铅遮线板的制做及其应用

１设计原则：头颅Ｘ射线摄影检查位置繁多，铅板为Ｘ射线摄影检查常用器材，为使被检器官显示在同一张照片上，采用单纯铅板遮挡暗盒的一半，未遮挡部分曝光。有的一个部位要两侧对照分析，需投照４次。为有效地规范照射野面积，必须按被摄组织的大小，形态变更照射野。变...     

骨盆数字化X射线摄影曝光剂量的优化研究

目的研究直接数字化X射线摄影照射剂量与成像质量的关系，确定骨盆X射线摄影的最佳摄影条件。方法以对比度一细节体模CDRAD2．0在不同照射剂量下所获取的影像的图像质量因子IQF，进行ANOVA及SNK统计学分析，确定最佳照射条件。应用X射线摄影模拟人拍摄骨盆X射线影像，按照欧共体（CEC）图像质量标准验证最佳摄影条件与常规摄影条件下照射剂量与成像质量的差别。结果不同照射剂量条件下，对比度一细节体模影像质量因子IQF有显著性差别（P=0．0001），照射剂量大于0．61mGy时，不同剂量组间IQF差异无统计学意义。对以最佳照射条件和常规照射条件所拍摄的X射线摄影模拟人影像按照CEC标准评判，两者影像质量的差异无统计学意义。结论直接数字化X射线摄影时通过增大照射剂量可以提高影像质量，但是当曝光剂量达到足够大时，再增大曝光剂量并不能显著改善图像质量，影像质量与曝光剂量间存在一个优化剂量。标准体模骨盆X射线摄影的优化剂量为0．61mGy。     

斜射线摄影对直接数字化X线摄影系统影像质量的影响评价

目的探讨斜射线摄影对直接数字化X线摄影(DDR)系统影像质量的影响。方法(1)实验组使用DDR系统对直径5.5cm钢质球体进行重复摄影,X线入射角度分别为垂直(0°)、15°、30°、45°,并将影像打印出激光胶片。(2)对照组用屏-片系统替换DDR系统的平板探测器,摄影条件与实验组相同,得出传统照片。(3)分别对实验组和对照组的球体影像边缘进行微密度测量,评价2种成像方法所得影像边缘模糊值随入射X线角度而变化的情况。结果(1)实验组和对照组的影像边缘模糊值随着X线入射角度的增加而增大,角度越大,增幅越明显,在大角度时实验组增幅更加明显,当入射角度为45°时,实验组的边缘模糊值(y2值)达到(0.9240±0.0033)mm,而对照组的y2值为(0.4840±0.0033)mm。(2)X线管倾斜15°投照时,DDR系统和屏-片系统的影像边缘模糊值变化幅度差异无统计学意义,(15°x)t=0.989,P=0.336;(15°y1)t=0.039,P=0.969。X线管倾斜30°和45°投照时,两系统的影像边缘模糊值变化幅度差异有统计学意义,(30°x)t=18.439,P=0.001;(30°y1)t=10.308,P=0.001;(30°y2)t=21.811,P=0.001;(45°x)t=31.315,P=0.001;(45°y1)t=107.727,P=0.001;(45°y2)t=160.863,P=0.001。结论(1)DDR系统在垂直和小角度倾斜X线管时,影像边缘模糊值与值屏-片系统差异不大,成像质量较好。(2)DDR系统在X线管倾斜角度较大时,影像边缘模糊增幅明显大于屏-片系统,成像质量受到影响。     

Histological investigation of osseous changes of mandibular condyles with backscattered electron images

OBJECTIVES: This study aims to confirm the radiographic morphology of mandibular condyles with microscopic observation and to investigate the mechanism of osseous changes of adult human mandibular condyles. METHODS: Following the radiographic examinations of ten temporomandibular joints (TMJs) from five cadavers using conventional tomography, helical CT and limited cone beam CT for dentistry (limited CBCT), ten mandibular condyles were removed. Micro CT images were made of the undecalcified dissected joints in the sagittal plane, perpendicular to the long axis of the condyles, to produce images similar in orientation to the radiographic images. Tissue morphology was observed through backscattered electron images and elemental analysis using electron probe microanalysis (EPMA). The microscopic findings were compared with the radiographic findings. RESULTS: Limited CBCT images most accurately depicted erosive change of the bone cortex of the mandibular condyle. EPMA indicated bone remodelling in all mandibular condyles analysed, which showed cartilage calcification different from typical enchondral ossification. No finding of dissolution or disruption of the superficial soft tissue was observed in all specimens, including those presenting radiographic findings of osteoarthrosis. Active bone remodelling with hypertrophic changes of superficial soft tissue was observed in mandibular condyles, which implied radiographic findings of osteoarthrosis. CONCLUSIONS: The high detectability of limited CBCT images on bony morphology of mandibular condyles was confirmed. It is speculated that bone remodelling of adult human mandibular condyles is brought about by cartilage calcification. It was suggested that the osseous changes classified as osteoarthrosis with radiographic images are normal bone remodelling.     

Shifting bone marrow edema of the knee

Objective. The purpose of our study is to describe shifting bone marrow edema in the knee as the MR imaging feature of intra-articular regional migratory osteoporosis of the knee.Patients and methods. Five men, aged 45–73 years, were referred by orthopedic surgeons for MR imaging evaluation of knee pain, which had been present for 2 weeks to 6 months. One patient had a prior history of blunt trauma. None had risk factors for osteonecrosis. Four patients had two MR examinations and the patient with prior blunt trauma had four. Plain radiographs were obtained in all patients.Results. In all cases, a large area of marrow edema initially involved a femoral condyle, with migration of the bone marrow edema to the other femoral condyle, tibia, and/or patella occurring over a 2- to 4-month period. Adjacent soft tissue edema was present in all five patients, while none had a joint effusion. Radiographs of two patients showed generalized osteopenia.Conclusion. In the absence of acute trauma or clinical suspicion of infection, a large area of bone marrow edema without a zone of demarcation may represent intra-articular regional migratory osteoporosis. Demonstration of shifting bone marrow edema on follow-up examinations suggests this diagnosis.     

Impact of sonography in gouty arthritis: comparison with conventional radiography, clinical examination, and laboratory findings

OBJECTIVE: To explore the typical sonographic features of gray-scale and Power Doppler of acute and chronic gouty arthritis in conjunction with radiographic, clinical, and laboratory findings. MATERIALS AND METHODS: All hand, finger, and toe joints of 19 patients with acute and chronic gout were examined with gray-scale and Power Doppler sonography. The number and size of bone changes detected with sonography was compared to radiographic findings. Vascularization of the synovial tissue was scored on Power Doppler (grades 0-3), and was compared with clinical appearance, including swelling, tenderness, and redness (grades 0-3). RESULTS: In acute gout, mild to moderate echogenic periarticular nodules with sonotransmission and hypervascularization of the edematous surrounding soft tissue were found. In chronic gout, tophaceous nodules completely blocked transmission of US wave, leading to strong reflexion and dorsal shadowing in a minority of cases. No significant difference in the detection of large bone changes (>2mm) was found between sonography and radiography. However, gray-scale sonography was significantly more sensitive in the detection of small bone changes (p<0.001). Power Doppler scores were statistically significantly higher than clinical examination scores (p<0.001). DISCUSSION: Sonography is superior to radiographs in evaluating small bone changes. The inflammatory process in joints can be better detected with Power Doppler sonography than with clinical examination. Typical sonographic appearance of acute and in particular of chronic gout might provide clues on gouty arthritis that adds to the information available from conventional radiography, clinical, and laboratory findings.     

Periosteal transplantation in the treatment of osteochondritis dissecans

Osteochondritis dissecans in the femoral condyle of the knee in 3 patients was treated with periosteal transplantation. The cavities were curetted to cancellous bone and a tibial periosteal graft was lined to the excavation and fixed with human tissue glue (Tisseel R). By clinical and radiographic follow-up, we find this modality of treatment as a hopeful prospect in severe cases, though a demarcation of indication is still a challenge for investigation.     

膝关节运动性损伤的磁共振成像评分系统及其应用价值

目的：探讨合适的膝关节运动性损伤的磁共振评分系统。方法回顾性分析14～45岁60例运动性膝关节损伤的磁共振成像（MRI）影像学表现,包括：骨质、半月板、韧带及软组织损伤等异常改变,并进行MRI评分。结果60例膝关节的MRI检查均可见骨挫伤,共105处（其中38例为单发;22例为2处或多发）,表现为长或稍长T1信号,在脂肪抑制序列上呈明显高信号,呈地图样、片状、斑点状等;另外,合并半月板损伤43例,韧带损伤29例,关节积液54例和关节周围软组织损伤23例。结论 MRI检查可以准确地发现膝关节运动性损伤的部位及形态,MRI评分系统能准确的量化膝关节损伤的程度。     

常规数字化X线摄影与组织均衡技术在鼻骨外伤诊断的比较

目的：探讨数字化X线摄影（DR）中组织均衡技术在鼻骨外伤诊断中的应用价值。方法：对94例鼻骨外伤患者分别行常规鼻骨侧位摄片,对直接获得的图像和采用组织均衡技术进行后处理获得的图像进行比较,比较两组影像的图像质量情况。结果：常规摄影技术得到的图像需反复调节不同的窗宽、窗位,才能显示密度、厚度不同的鼻骨与软组织;组织均衡技术可在同一帧图像上清晰显示鼻骨及其邻近软组织。结论：采用组织均衡技术能将密度和厚度不同的鼻骨及其邻近组织在同一帧图像上清晰显示。     

Nodal osteoarthritis and gout: a report of four new cases

 Recently gout has been recognized as a cause of inflammation in patients with nodal osteoarthritis. We reviewed the clinical data and radiographs of four patients with known osteoarthritis of the interphalangeal joints of the hands who developed gout. Radiographic changes of osteoarthritis in the affected interphalangeal joint were present in all four patients. In our cases, radiographic findings were typical of gout in one patient, including the presence of large eccentric soft tissue masses and periarticular erosions. In three patients, radiographic findings were non-specific, including only a small eccentric nodule in one patient, diffuse soft tissue swelling in a second, and a large calcified soft tissue mass with bony erosions in a third. Whenever a patient with interphalangeal joint osteoarthritis presents with an acute episode of inflammation the possibility of gout should be considered. Recognition of gout will allow the timely initiation of appropriate therapy.     

军事训练膝关节不同应力性损伤的高场MRI表现

目的探讨军事训练膝关节不同应力性损伤的特点、生物力学特征及其高场MRI表现。方法回顾性分析我院2010年12月—2012年12月军事训练膝关节应力性损伤患者的MRI资料共102个膝关节,根据应力性质及应力作用的特点、组织损伤部位及特点,对每一个膝关节的MRI资料进行分析。结果 102个膝关节中,股骨远端38例,胫骨近端42例,前交叉韧带98例,后交叉韧带31例,内侧副韧带34例,外侧副韧带24例,关节腔积液76例,内侧半月板18例,外侧半月板11例,5例为单纯型损伤,97例为复合型损伤。交变应力性损伤时MRI可见骨髓腔内线状、斑片状长T1长T2信号影;拉应力性损伤时MRI可见与骨干平行的软组织异常信号,骨髓腔内片状异常信号,有骨折时骨髓腔锯齿状、斜行或横行的长T1短T2信号影;压应力性损伤时MRI可见胫骨平台的骨髓水肿、压缩骨折、半月板损伤和软组织损伤;剪切应力性损伤时MRI可见交叉韧带、侧副韧带、半月板、股骨髁或胫骨平台的异常信号。结论军事训练膝关节应力性损伤的程度与军事活动的频度、强度和训练科目有关,军事训练膝关节所遭受的应力作用不是单一的,而是几种应力的共同作用,MRI能敏感地发现不同应力所致的组织损伤特点,对膝关节应力性损伤各期的评价和诊断具有明显的优势,能为军事训练应力性损伤的预防和早期干预提供借鉴。     

腓肠神经营养血管蒂皮瓣交腿修复胫前及足部软组织缺损

目的探讨腓肠神经营养血管蒂皮瓣交腿修复胫前及足部软组织缺损的临床疗效。方法2004年1月～2007年12月,对11例胫前及足部外伤感染后软组织缺损坏死、骨外露彻底清创后,采用腓肠神经营养血管蒂皮瓣交腿修复,胫前软组织缺损6．0cm×5．0cm～16．0cm×8．0cm;足部软组织缺损4．0cm×3．0cm～14．0cm×6．8cm,皮瓣切取范围为5．6cmX4．5cm～18．0cm×10．0cm,蒂最长达18cm。结果术后10例皮瓣Ⅰ期愈合,1例Ⅱ期愈合。随访3个月～3年,质地良好,外观较满意。足背皮瓣中1例边缘坏死,1例老年患者出现下肢交腿压疮,浅部针眼感染2例。膝、踝关节功能受影响小,皮瓣感觉仅有少部分恢复。结论腓肠神经营养血管蒂皮瓣交腿是修复胫前及足部软组织缺损的有效方法。老年患者固定时间长容易引起关节僵硬,宜慎用,交腿后注意固定及防止压疮。     

Tumoral calcinosis-like lesion of the proximal linea aspera

Tumoral calcinosis is presently a poorly defined disease. In its classic form, it consists of multiple large foci of benign mineralization in the soft tissue adjacent to bone near large joints. Patients are generally of African descent and are adolescents or young adults at presentation. Both metabolic and traumatic etiologies have been proposed. We report six adult Caucasian patients with lesions that pathologically resembled tumoral calcinosis. All lesions were small (less than 3 × 3 cm) and were located along the proximal linea aspera of the femur. All patients presented with pain. Because of the atypical patient population and the unusual size and location of the lesions, we refer to this process as a tumoral calcinosis-like lesion. A typical radiographic appearance and location, together with appropriate clinical history, can strongly suggest this diagnosis.