Continuously moving table 3D MRI with lateral frequency-encoding direction.

A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses.     

Image processing in digital radiography

Image processing is a critical part of obtaining high-quality digital radiographs. Fortunately, the user of these systems does not need to understand image processing in detail, because the manufacturers provide good starting values. Because radiologists may have different preferences in image appearance, it is helpful to know that many aspects of image appearance can be changed by image processing, and a new preferred setting can be loaded into the computer and saved so that it can become the new standard processing method.Image processing allows one to change the overall optical density of an image and to change its contrast. Spatial frequency processing allows an image to be sharpened, improving its appearance. It also allows noise to be blurred so that it is less visible. Care is necessary to avoid the introduction of artifacts or the hiding of mediastinal tubes.     

桥式石膏悬吊牵引治疗小儿股骨干骨折

我院自 1992年 1月 - 2 0 0 0年 12月 ,应用桥式石膏悬吊牵引治疗小儿股骨干骨折患者 89例 ,疗效满意 ,报道如下。1　临床资料本组 89例中男 6 1例 ,女 2 8例 ;年龄 2ｄ～ 6岁 ,平均 3 5岁。左侧 39例 ,右侧 4 5例 ,双侧 5例。上1/ 3骨折 2 4例 ,中 1/ 3骨折 5 1例 ,下 1/ 3骨折 14例。横形骨折 36例 ,斜形骨折 30例 ,螺旋形骨折 18例 ,粉碎性骨折 5例。闭合性骨折 85例 ,开放性骨折4例 ,均在伤后 4 8ｈ内就诊。2　治疗方法2 1　桥式石膏制作　患儿仰卧位 ,双小腿前后石膏托 ,后托宽占周径 1/ 2 ,长自足跟至窝 ;前托宽占周径 1/ 3,长自踝…     

龈下残根修复前正畸治疗五例

目的　对损坏至龈缘下 1 5～ 3 5mm的前牙牙根在修复前行正畸牵引 ,当损坏平齐龈缘时再桩冠修复的方法进行探讨。方法　 3例外伤、2例根面龋的患者 ,共 6个牙根接受完善根管治疗 ,修复前正畸暴露损坏 ,电刀修整牙龈 ,然后桩冠修复。结果　 5例患者在修复后均取得了较满意的效果。结论　若前牙牙根损坏位于龈下釉牙骨质交界处 ,在修复前进行正畸治疗 ,既可保留残根 ,又可制作出有较好功能和美观效果的修复体     

与时俱进 全面开展生活方式教育

该文从疾病谱和死因谱的改变、医学模式的转变、卫生经费的降低、自我保健意识的改变四个角度,论述了全面开展 生活方式教育的必要性和重要性;从以社区为依托、以医院为基础、以生活方式为指导三个方面,探讨了生活方式教 育的工作模式.     

股骨颈骨折后选择性血管造影评价股骨头血液循环

目的 探讨选择性血管造影检查对评价股骨颈骨折后早期股骨头血液循环损伤及影响因素的价值。方法采用选择性旋股动脉及支持带动脉造影(DSA)，对9例2～23天内单侧股骨颈骨折患者血管损伤和血液循环改变进行评价。结果髋关节囊内出血2例，骨内出血4例，下、后支持带动脉损伤和血管移位各3例。患髋牵引时，除外下支持带动脉，其他支持带动脉无显影或仅显示起始部主干，相应股骨头颈部几无灌注成像，静脉显影延迟；髋关节维持伸直内旋位或囊内注入生理盐水后造影，所有支持带动脉无明确显影或仅显示其主干，股骨头颈部无灌注、染色，静脉显影延迟。结论选择性旋股内、外侧动脉DSA技术是一项准确评价股骨颈骨折后股骨头血液循环损伤及影响因素的微创性检查方法；股骨头血液循环受髋关节体位、囊内压和牵引等因素影响；牵引可导致或加重股骨颈骨折后股骨头缺血。     

Dosimetric Characteristics of the Siemens IGRT Carbon Fiber Tabletop

In this work, the dosimetric characteristics of a new commercial carbon fiber treatment table are investigated. The photon beam attenuation properties of the Siemens image-guided radiation therapy (IGRT) tabletop were studied in detail. Two sets of dosimetric measurements were performed. In the first experiment a polystyrene slab phantom was used: the central axis attenuation and the skin-sparing detriment were investigated. In the second experiment, the off-axis treatment table transmission was investigated using a polystyrene cylindrical phantom. Measurements were taken at the isocenter for a 360° rotation of the radiation beam. Our results show that the photon beam attenuation of the Siemens IGRT carbon fiber tabletop varies from a minimum of 2.1% (central axis) to a maximum of 4.6% (120° and 240° beam incidence). The beam entrance dose increases from 82% to 97% of the dose at the depth of maximum for a clinical 6-MV radiation field. The depth of maximum also decreases by 0.4 cm. Despite the wedge cross section of the table the beam attenuation properties of the IGRT tabletop remain constant along the longitudinal direction. American Association of Medical Dosimetrists.     

火把花根片治疗面部激素依赖性皮炎疗效观察

目的：观察火把花根片治疗激素依赖性皮炎的疗效和安全性。方法：患者81例，分为治疗组和对照组。对照组：口服氯雷他定片，10mg／次，1次／天，同时外用氧化锌软膏；治疗组：在对照组用药的基础上加服火把花根片，5片／次，3次／天；疗程均为2个月。结果：治疗组总有效率达68．29％，对照组总有效率达24．24％，两组疗效比较有显著性差异（P〈0．01）。结论：火把花根片治疗面部激素依赖性皮炎安全、有效。     

小剂量氯胺酮咪唑安定辅助硬膜外下剖腹产手术的临床探讨

目的对比观察剖腹产选用连续硬膜外麻醉时，辅助麻醉用药镇静及对牵拉反应抑制效果。方法选择行剖腹产手术产妇60例在硬膜外麻醉效果满意后，随机分两组各30例。Ⅰ组：哌替啶50mg，异丙嗪25mg单次静注。Ⅱ组：氯胺酮28．5mg，咪达唑仑1．42mg单次静注。分组记录用药前，1min，5min，15min及术毕产妇SpO2、RR、HR、MAP值；记录手术时间、术毕苏醒例数、术中恶心躁动例数；记录术毕产妇OAA／S评分；记录新生儿娩出时Apger评分。结果两组术中镇静、抑制牵拉反应效果均满意。两组RR、BP、HR、SpO2均平稳；术毕两组OAA／S评分均为4-5分；新生儿Apger评分均正常。结论两组方法效果确切，对产妇和新生儿安全。     

白霉素片溶出度实验研究

本文采用转蓝法紫外分光光度法测定了三家药厂七批白霉素片体外溶出度,求得T_(50),Td威布尔函数参数具有显著差异,表明不同厂家所生产的白霉素片的溶出度相差显著,提出了影响药物溶出的某些因素,建议国产白霉素片有必要制定溶出标准。