High resolution solid-state 29si nmr spectroscopy of silicone gels used to fill breast prostheses

We have used ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy to study the chemical structure of the silicone gels in virgin and explanted breast prostheses. Despite evidences of alteration in the morphological appearance of the silicone gel inside the breast prosthesis, our results do not reveal changes in the chemical nature and structure of the silicone gels after implantation. In addition to the main ²⁹Si resonance peak at ?22.26 ppm that corresponds to the resonance frequency of the D repeat unit of the polysiloxane chains, the high sensitivity of our NMR technique allows the detection of very low concentrations of silicone compounds. Within our experimental detection limit of 0.2%, no signal between ?90 ppm and ?150 ppm are observed. This indicates that no silica products are present inside the gel of the prostheses. Furthermore, our ²⁹Si NMR spectra indicate differences in the chemical compositions of the silicone gels from different manufacturers.     

胫骨髁间嵴增生在膝关节退行性变诊断中的临床价值探讨

本研究分３组，典型膝关节退行性变组（简称退变组）５０例，早期膝关节退行性变组（简称早退组）１５例，对照组３０例。分别测量每组Ｘ线片的内、外侧胫骨髁间嵴角与内、外侧嵴高平台比值。经统计学处理，两指标所测值在退变组与对照组及早退组与对照组之间有显著性差异（Ｐ＜０．０５），而退变组与早退组之间则无显著性差异（Ｐ＞０．０５）。结果表明：胫骨髁间嵴硬化变尖不仅是膝关节退行性变的特征性表现之一，而且是其早期Ｘ线征象。     

Image technique optimization in MR imaging of a titanium alloy joint prosthesis

The purpose of this study was to explore systematically the effect of the imaging parameters changeable by the user in spin-echo (SE) imaging sequences to minimize image distortion when imaging joint prostheses. A titanium alloy hip joint prosthesis was studied at 1.0 T. The SE imaging parameters were bandwidth/pixel (BW/p), TE, strength of encoding gradients (matrix size), echo train length (ETL), and direction of phase and frequency encoding. The effect of ETL in rapid acquisition relaxation enhanced (RARE) sequences was also evaluated with a turbo-SE sequence using a different ETL with the same TR and an effective TE. It is concluded that an optimized image quality can be achieved in SE imaging by using a high bandwidth/pixel value (at least 130 Hz/pixel), a high resolution matrix (256–512), sequences with multiple refocusing, and a frequency-encoding axis parallel to the long axis of the prosthesis. The degree of distortion is reduced with this optimized technique.     

复合带瓣人工血管替换升主动脉和主动脉瓣(24例报告)

报告２４例升主动脉瘤伴主动脉瓣关闭不全行升主动脉和主动脉瓣替换及冠状动脉开口移植术（Ｂｅｎｔａｌ术２２例，底盘法２例）。１３例伴有升主动脉夹层分离，对其中８例ＤｅＢａｋｅｙＩ型者，以Ｔｅｆｌｏｎ毡条内外加固主动脉切端后吻合。１３例用人工血管周围间隙与右心耳吻合以控制升主动脉吻合之外的出血。３例以人工血管片环包主动脉吻合口控制局部广泛渗血及出血。２例术毕不能脱离体外循环死亡，手术死亡率８３％。随访平均２１８个月，２例死于蛛网膜下腔出血，１例右股动脉栓塞经手术治愈；其余病人康复良好，心功能（ＮＹＨＡ）Ｉ～ＩＩ级。     

Delayed Reduction of Irreducible Chronic Posterolateral Dislocation of the Knee with Buttonholing of the Medial Femoral Condyle

Abstract Traumatic knee dislocations are relatively rare and almost always respond to closed reduction; however, a small percentage of knee dislocations are irreducible and in these cases open reduction is frequently required. A 65-year-old man with an unreduced posterolateral knee dislocation with laterally dislocated patella was seen 3 weeks after a motor vehicle accident. Medial femoral condyle was found buttonholed through the medial capsule together with the medial collateral ligament and lying in the medial joint space that allowed posterior rotary dislocation of the joint. Both cruciate ligaments and medial meniscus were torn. There was no evidence of any vascular or nerve injury. Reduction was accomplished by removal of the capsuloligamentous structures which were incarcerated in the trochlea and intercondylar notch and by excision of meniscal tear. Following posterior cruciate ligament reconstruction with patellar tendon autograft, lateral patellar release, vastus medialis advancement, and gracilis transfer were done.     

80 例人工全髋关节置换术的中期疗效分析

目的 探讨人工全髋关节置换术的疗效。方法 回顾性研究了1997年3月至2002年12月期间连续全髋关节置换术80例(92髋)患者，平均随访54个月(14～84个月)，分析其中期疗效。结果 翻修率为5．4％(5／92)，Harris髋评分为优良以上84．8％(78／92)，中等8．7％(8／92)，差6．5％(6／92)。结论 外科技术的提高和假体生物工程的发展，提高了全髋关节置换术重建关节功能的疗效。     

弹性义齿修复的临床效果观察

目的：了解弹性义齿修复的临床效果，为临床应用提供参考。方法：152例门诊缺牙患者，制作弹性义齿修复体188件，上颌130件，下颌58件。Kennedy一类缺损修复6件，Kennedy二类缺损修复4件，Kennedy三类缺损修复102件，Kennedy四类缺损修复76件。通过1－4年的观察，从形态和功能、固定和稳定、颜色和美观以及对组织保健判断对义齿的满意程度，并进行临床效果评价。结果：79例95件弹性义齿具有良好的美观效果，颜色满意，感觉舒适，满意和较满意率达100％，Kennedy三、四类缺损修复率为94．74％。弹性义齿对Kennedy一类缺损修复的满意和比较满意率为66．67％；对Kennedy二类缺损修复的满意和比较满意率为50．00％；对Kennedy三类缺损修复的满意和比较满意率为96．15％；对Kennedy四类缺损修复的满意和比较满意率为84．21％。结论：(1)弹性义齿是一种美观、舒适、对基牙预备甚少的可摘局部义齿修复形式。（2）弹性义齿较适合咀嚼压力小而缺牙数目不多的前牙和前磨牙缺失的修复。     

Factors influencing survival of reconstructions. Consensus report of Working Group 2

Abstract: In order to evaluate the level of evidence of factors influencing the survival of reconstructions, systematic reviews of the relevant literature were prepared by a group of rapporteurs. The review papers were circulated to the members of the group before the conference and formed the basis for group and panel discussions. Subsequently, modifications were added to the review papers, and suggestions for consensus statements concerning the following topics were prepared and again critically reviewed in the group and in the plenum: Impact of (i) periodontal disease on the survival of tooth-supported reconstructions, (ii) post-surgical factors as supportive therapy on the survival of implant supported reconstructions, (iii) technical and/or biological complications on the survival of different types of reconstructions, (iiii) material choice for reconstructions on the survival of single crowns and fixed dental prostheses.