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.     

Radiographic study of osteoarthritic elbows in professional basebal pitchers

We examined radiographs of the elbows of the pitching arms of 79 professional baseball pitchers (mean age, 25.1 years; mean duration of professional career, 4.7 years) and noted the frequency and size of spurs, bone fragments, and intra-articular loose bodies according to site. The influence of duration of professional baseball career on these osteoarthritic changes was also investigated. The olecranon tip was the most frequent site of spurs (62/79; 78.5%), and fragmentation of the spur was detected in 17 joints. The frequency of spurs was also high at the medial margin of the olecranon, the tip of the coronoid process, the medial margin of the sigmoid notch, the medial margin of the trochlea and the olecranon fossa. In 38 subjects, spurs were observed at the distal portion of the radial notch of the ulna. However, few pitchers had osteoarthritic changes in the humeral capitellum or radial head. Intra-articular loose bodies were detected in 4 of 79 joints (5.1%), and bone fragments were present below the medial humeral epicondyle in 25 of 79 joints (31.6%). Osteoarthritic changes in the elbow joint appeared to be attributable mainly to traction stress and impingement associated with extension and valgus strain. Significant osteoarthritic changes were often found in professional pitchers whose careers exceeded 5 years.     

国人颅骨颌型的研究

本文测量了180例干燥颅骨的总面角、鼻面角和齿槽面角三项角度项目;分析了颅骨在性别和年龄上的颌型差异;探讨了颅骨发育中的某些变化趋势。本文的部分数据同其它文献作了比较     

Optimized and combined T1 and B1 mapping technique for fast and accurate T1 quantification in contrast-enhanced abdominal MRI.

Fast T(1) mapping techniques are a valuable means of quantitatively assessing the distribution and dynamics of intravenously or orally applied paramagnetic contrast agents (CAs) by noninvasive imaging. In this study a fast T(1) mapping technique based on the variable flip angle (VFA) approach was optimized for accurate T(1) quantification in abdominal contrast-enhanced (CE) MRI. Optimization methods were developed to maximize the signal-to-noise ratio (SNR) and ensure effective RF and gradient spoiling, as well as a steady state, for a defined T(1) range of 100-800 ms and a limited acquisition time. We corrected B(1) field inhomogeneities by performing an additional measurement using an optimized fast B(1) mapping technique. High-precision in vitro and abdominal in vivo T(1) maps were successfully generated at a voxel size of 2.8 x 2.8 x 15 mm(3) and a temporal resolution of 2.3 s per T(1) map on 1.5T and 3T MRI systems. The application of the proposed fast T(1) mapping technique in abdominal CE-MRI enables noninvasive quantification of abdominal tissue perfusion and vascular permeability, and offers the possibility of quantitatively assessing dilution, distribution, and mixing processes of labeled solutions or drugs in the gastrointestinal tract.     

MRI测量颈胸角在选择颈胸段脊柱手术入路中的临床应用

目的 :探讨在颈胸段脊柱术前应结合患者的颈胸段MRI的个体特征和疾病情况 ,选择手术创伤最小的手术入路。方法 :共 76例患者 ,其中 2 6例为颈胸段脊柱损伤 ,35例为颈胸段脊柱肿瘤 ,脊髓型颈椎病 12例 ,以及 3例颈胸段椎板减压术后后凸畸形。男 4 7例 ,女 2 9例。平均年龄 4 5 5岁 ,年龄范围 19～ 6 5岁。同时抽取 95套颈胸段MRI片。作胸骨上切迹向后水平延长线和胸骨上切迹向后上方至C7T1椎间盘前缘中点的连线 ,测量两线之夹角 ,称为颈胸角 (cervicothoracicangle ,CTA)。结果 :CTA平均为 4 7 6 4°(范围 2 5°～ 73°)。大于此平均角度且病灶在胸骨切迹水平线以上时可考虑低位下颈椎入路 ,5 0例 ;CTA较小 ,且病灶范围广 ,或尚累及T3 、T4,可以考虑经胸骨柄入路 ,13例 ;病灶范围广泛 ,经全胸骨入路 3例 ;Ⅰ期或Ⅱ期前后联合入路 5例 ;经右侧肩胛下后外侧胸腔入路 5例。结论 :颈胸段脊柱手术应尽量选择低位下颈椎入路等创伤较小的入路 ,其次考虑经胸骨柄入路。长节段脊柱受累的患者才考虑经右侧肩胛下后外侧胸腔或经全胸骨等创伤较大的入路。术前可以结合患者的病灶累及范围和颈胸手术角等MRI影像学表现 ,从而利于选择最合适的手术入路 ,减少手术风险、手术创伤和并发症 ,利于患者早日康复     

水前房角镜学的使命

水前房角镜学是新建的眼科学的一个分野,为眼科疾患病人服务是她的使命。水前房角镜学的最大优点是其含金量能百分之百地转化为读者的受益。     

胫骨高位截骨手术并发症23例次分析

[目的] 探讨胫骨高位截骨手术并发症的发生情况，并提出预防和治疗措施。[方法]2000年1月～2004年10月采用胫骨高位截骨术治疗膝骨关节炎合并内翻畸形患者126人，21人发生手术并发症，男4例，女17例；年龄48～64岁，平均61岁。术前拍摄站立膝关节正位X线片，测量股骨一胫骨角，计算截骨角度，采用外侧闭合胫骨高位截骨术矫正膝内翻畸形。[结果] 术后随访6～12个月，平均7．5个月。共21名患者发生各类并发症23例次．发生率为16．7％。其中发生胫骨骨折4例，腓总神经麻痹3例，出现深静脉血栓形成5例，膝内翻复发病例6例，内固定失败4例（其中2例合并膝内翻复发），感染1例。[结论] 降低胫骨高位截骨手术并发症需要术者熟悉局部解剖和精确的术前设计，提高手术技巧及完善的围手术期护理。     

单纯下颌骨磨削法矫治下颌角肥大

目的 探讨下颌角肥大骨磨削法治疗的临床效果。方法 在局部肿胀麻醉下，采用口内切口入路，常规分离显露下颌骨，在预定需要矫正的下颌骨区域，使用特殊器械磨削下颌骨体外侧皮质骨、下颌骨下缘及下颌角骨质，同时对部分肥大的咬肌进行处理，矫治下颌角肥大。结果 对58例下颌角肥大患者均行下颌骨磨削法矫治，除1例术中损伤下齿槽血管引起出血外，无其他并发症发生。术后随访6～18个月，全部病例取得良好的矫治效果。结论 下颌骨磨削法矫治下颌角肥大是一种并发症少、安全有效的好方法。与截骨矫治下颌角肥大的方法相比，该术式保留了下颌骨的内板。维持了颌颈区的立体感。     

肘关节后脱位并尺骨冠状突骨折9例临床疗效分析

目的 探讨肘关节后脱位并尺骨冠状突骨折的治疗方法。方法 总结2000年3月～2003年5月9例肘关节后脱位合并尺骨冠状突骨折患者的治疗经验，根据骨折类型分别采用内外侧入路对8例患者进行手术治疗，术后配合早期功能锻炼。结果 所有患者随访8～24个月，根据HSS评分标准，优5例（55.6%)，良2例（22.2%)，一般2例（22.2%)，优良率77.8%，无严重肘关节并发症发生。结论 选择恰当的手术入路和早期功能锻炼是提高该类骨折效果的关键。