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101.
102.
The ability to reconstruct complex facial injuries is still a considerable challenge despite the development of microsurgical techniques. The reconstructive options for conditions such as panfacial burns are severely limited. The result after multiple surgical procedures in this group is often poor in terms of function and cosmesis. Facial transplantation provides a potential solution, but opinion is currently divided about the extent to which the potential benefits to the quality of life can be justified when weighed against the technical, psychological and immunological risks. This paper reviews the current status of the debate and argues that a rigorous research strategy is the only logical basis for countering the ethical objections to a procedure that offers considerable benefits over existing reconstructive options.  相似文献   
103.
持续被动活动对兔重建前交叉韧带生物力学特性的影响   总被引:2,自引:0,他引:2  
目的:采用半腱肌腱重建兔前交叉韧带(ACL),探讨持续被动活动(CPM)对移植物生物力学特性的影响。方法:对30只8月龄雄性新西兰大白兔右侧后肢膝关节行自体双股半腱肌腱移植重建前交叉韧带手术。术后随机分为CPM组和非CPM组两组:CPM组术后第2天开始采用自制兔膝关节CPM器进行持续被动活动,共6周;非CPM组仅笼养。分别于术后第6、12、24周取材,每组每次取5只行生物力学观察。结果:与非CPM组相比,CPM组大部分标本两束融合成一体。从术后6周到24周,所有移植物的最大载荷、最大应力、弹性模量以及这些指标和其对照侧ACL的比值逐渐增加。在术后6、12、24周时,CPM组移植物最大载荷分别为22.72N、79.56N、122.20N,最大应力分别为4.58MPa、13.62MPa、21.79MPa;非CPM组移植物最大载荷分别为16.00N、70.68N、96.20N,最大应力分别为3.07MPa、11.58MPa、17.89MPa。3个时间点两组间上述指标差异均具有统计学意义(P<0.05)。结论:半腱肌腱重建兔前交叉韧带术后早期进行持续被动活动可明显提高移植物的生物力学性能。  相似文献   
104.
Current techniques for tibial graft fixation in four tunnels double bundle (DB) anterior cruciate ligament (ACL) reconstruction are by means of two interference screws or by extracortical fixation with a variety of different implants. We introduce a new alternative tibial graft fixation technique for four tunnels DB ACL reconstruction without hardware. About 3.5 to 5.5 cm bone cylinder with a diameter of 7 mm is harvested from the anteromedial (and posterolateral) tibial bone tunnel (s) with a core reamer. The anteromedial (AM) and posterolateral (PL) hamstring tendon grafts (or alternatively tendon allografts) are looped over an extracortical femoral fixation device and cut in length according to the total femorotibial bone tunnel length. The distal 3 cm of each, the AM- and PL bundle graft are armed with two strong No. 2 nonresorbable sutures and the four suture ends of each graft are tied to each other over the 2 cm wide cortical bone bridge between the tibial AM and PL bone tunnel. In addition the AM- and/or PL bone block which was harvested at the beginning of the procedure is re-impacted into the two tibial bone tunnels. A dorsal splint is used for the first two postoperative weeks and physiotherapy is started the second postoperative day. The technique is applicable for four tunnels DB ACL reconstruction in patients with good tibial bone quality. The strong fixation technique preserves important tibial bone stock and avoids the use of tibial hardware which knows disadvantages. It does increase tendon to bone contact and tendon-to-bone healing and does reduce implant costs to those of a single bundle (SB) ACL reconstruction. Revision surgery may be facilitated significantly but the technique should not be used when bony defects are present. In case of insufficient bone bridge fixation or bone blocks hardware fixation can be applied as usual. Not supported by outside funding or grant(s): No benefits in any form have been received, or will be received, from a commercial party related directly or indirectly to the subject of this article. The study complies with the current laws of the country, in which it was performed.  相似文献   
105.
OBJECTIVE: The quality of single-photon emission computed tomography (SPECT) imaging is hampered by attenuation, collimator blurring, and scatter. Correction for all of these three factors is required for accurate reconstruction, but unfortunately, reconstruction-based compensation often leads to clinically unacceptable long reconstruction times. Especially, efficient scatter correction has proved to be difficult to achieve. The objective of this article was to extend the well-known transmission-dependent convolution subtraction (TDCS) scatter-correction approach into a rapid reconstruction-based scatter-compensation method and to include it into a fast 3D reconstruction algorithm with attenuation and collimator-blurring corrections. METHODS: Ordered subsets expectation maximization algorithm with attenuation, collimator blurring, and accelerated transmission-dependent scatter compensation were implemented. The new reconstruction method was compared with TDCS-based scatter correction and with one other transmission-dependent scatter-correction method using Monte Carlo simulated projection data of (99m)Tc-ECD and (123)I-FP-CIT brain studies. RESULTS: The new reconstruction-based scatter compensation outperformed the other two scatter-correction methods in terms of quantitative accuracy and contrast measured with normalized mean-squared error, gray-to-white matter and striatum-to-background ratios, and also in visual quality. Highest accuracy was achieved when all the corrections (i.e., attenuation, collimator blurring, and scatter) were applied. CONCLUSIONS: The developed 3D reconstruction algorithm with transmission-dependent scatter compensation is a promising alternative to accurate and efficient SPECT reconstruction.  相似文献   
106.
单束重建前交叉韧带骨道位置对临床效果影响的研究   总被引:3,自引:0,他引:3  
目的:探讨前交叉韧带重建术骨道位置对临床效果的影响。方法:2005年5月至12月于我所行自体腘绳肌腱单束重建前交叉韧带手术患者72例,采用其侧位X线平片测量骨道位置,结合膝关节功能评分、KT-2000测试结果进行分析。结果:患者的IKDC、Lysholm和Tegner评分以及KT-2000在134N下屈膝30度和90度位膝关节前后位移情况均较术前显著改善(P<0.01)。股骨骨道位于Blumensaat’s线的后23.87%,胫骨骨道位于胫骨平台全长的前38.25%。膝关节伸直受限患者胫骨骨道位于胫骨平台前34.19%,伸直正常患者胫骨骨道位于胫骨平台的前38.91%,二者相比具有显著性差异(P<0.05〉。KT-2000屈膝30度位膝关节前后位移值大于等于3mm患者的胫骨骨道位于胫骨平台的前44.78%,位移小于3mm患者胫骨骨道位于胫骨平台的37.39%,二者相比具有显著性差异(P<0.01)。结论:单束重建前交叉韧带手术使患者关节稳定性与功能均得到显著改善。X线测量可较客观、准确地反映骨道定位情况,骨道位置与临床效果相关;本次研究显示比较理想的骨道位置在X线侧位片上位于胫骨平台的前34~37%。  相似文献   
107.
Upper urinary surgery is an important area of urology surgery. Open surgery used to be the gold standard of upper urinary surgery. With the development of medical techniques, minimal invasive surgeries including laparoscopic and robot assisted-laparoscopic surgery have gradually replaced the open surgery. Because of the complexity and diversity of upper urinary diseases, surgeries sometimes are difficult, and minimal invasive surgeries require higher surgical abilities of urologists than open surgeries. In recent years, depending on our surgical experience and international reports, our team from three Chinese medical centers summarizes techniques of upper urinary minimal invasive surgeries. For malignant diseases, such as renal and ureteral carcinomas, it’s important to totally remove the tumor first, and then to avoid the surgical injuries. We summarize surgical experience of retroperitoneal laparoscopic partial nephrectomy for moderately complex renal hilar tumors. Our team modified minimal invasive techniques for some complex tumors, including ring suture technique for renal hilar tumors, internal suspension technique for renal ventral tumors, and combination retroperitoneal laparoscopic surgery with mini-flank incision for complex renal tumors. While for begin diseases, urologists should focus on the resections and surgical injuries at the same time. We have reported the novel technique of laparoscopic aspiration for central renal angiomyolipoma, making the surgery simple and available. For reconstruction surgeries, operations should be based on several principals. We generalize it as “4TB principals”, which include “tension-free”, “water-tight”, “thin suture”, “no touch of the key area” and “protecting the blood supply”. Depending on the localization, length, and etiology of the strictures, different techniques are required. Our team summarize the pyeloplasty, ureteral reimplantation and ileal ureter replacement based on our surgical experience. For infant upper urinary surgeries, our team has made invasive surgeries that can be used in complex diseases, such as duplex kidney. Based on years of surgical techniques, our modified surgeries achieve a better subjective cosmetic result than the traditional surgeries. In the future, the standardized, practical, simple and individual minimal invasive surgical technique will become the main direction in the future researches.  相似文献   
108.
目的:探讨低X线辐射剂量及低碘浓度等渗对比剂联合iDose4迭代重建技术(L-LWiDose4)在新生儿先天性心脏病CT血管成像(CTA)中的可行性。方法:前瞻性收集2015年1月至2018年3月温州医科大学附属第二医院育英儿童医院新生儿科需行心脏CTA检查的连续102例患者,随机分为2组,采用不同的扫描方案:常规组(A组)53例,采用100 kVp、100 mAs、碘海醇(350 mg I/mL),重建方式为滤波反投影(FBP)算法;实验组49例,采用80 kVp、80 mAs、碘克沙醇(270 mg I/mL),根据iDose4迭代算法可以得到iDose4-1~iDose4-7 7组图像,选取iDose4-2~iDose4-6 5组图像,分别记为B组、C组、D组、E组、F组。依据新生儿体质量采取不同的对比剂注射剂量并计算碘摄入量。测量主动脉弓、气管分叉水平降主动脉、肺动脉干及主动脉弓层面两侧胸大肌和竖脊肌CT值,测量气管分叉层面周围空气CT值的标准差(SD),记为背景噪声,计算信噪比(SNR)和对比噪声比(CNR),并对图像质量进行主观评价。记录容积CT剂量指数(CTDIvol)和剂量长度乘积(DLP),并计算有效剂量(ED)和体型特异性剂量评估(SSDE)。以手术或心导管造影为“金标准”,统计并比较各组CTA检查的诊断符合率。结果:实验组CTDIvol、SSDE、DLP、ED较常规组分别降低了57.08%、56.62%、58.31%、56.97%(P<0.05)。常规组、实验组对比剂碘摄入量分别为(1.83±1.27)g和(1.61± 1.36)g,差异有统计学意义(P<0.05)。B组、F组图像客观评价不及A组、C组、D组、E组(P<0.05)。A组、D组、E组图像主观评价差异无统计学意义。常规组、实验各组诊断符合率分别为98.6%、81.6%、87.7%、97.9%、97.9%、96.9%,差异无统计学意义(P>0.05)。结论:80 kVp、80 mAs、碘克沙醇(270 mg I/mL)联合iDose4迭代重建技术新生儿先天性心脏病CTA检查,在降低患者的电离辐射剂量和对比剂碘剂量的同时,其图像质量能够满足临床诊断需要。  相似文献   
109.
目的:探讨下颈椎椎弓根轴线与椎板平面夹角的影像学测量及其临床意义。方法:对排除颈椎畸形 的30例患者颈椎行三维重建CT扫描,在重建后的C3~C7特定CT图像上测量椎弓根轴线与椎板平面夹角。结果:1) C3~C7左右两侧横向椎弓根-同侧椎板角分别为98.3°±6.3°,98.0°±5.1°,97.5°±6.9°,95.1°±5.0°,85.8°±5.4°和96.7°±8.2°, 98.7°±7.1°,97.8°±3.6°,93.2°±6.2°,86.8°±5.7°;C3~C6的夹角大于90°,C7的夹角小于90°,呈逐渐减小趋势。除了C6与C3 和C7与其他节段外,其余各节段间的差异均无统计学意义(均P>0.05)。2)C3~C7左右两侧横向椎弓根-对侧椎板角分别 为0.2°±4.5°,1.2°±7.2°,–0.8°±6.8°,–3.3°±5.4°,–14.7°±4.0°和–1.6°±5.4°,1.9°±4.6°,–0.5°±6.0°,–4.6°±5.3°,–13.7°±3.4°, 呈先增大后减小趋势,C4的夹角最大。除了C6与C3,C6与C4,C7与其他节段外,其余各节段间的差异均无统计学意义 (均P>0.05)。3)C3~C7左右两侧纵向椎弓根-同侧椎板角分别为77.7°±7.6°,77.0°±7.1°,85.3°±8.4°,94.1°±2.2°,94.9°±3.8° 和78.5°±7.1°,76.2°±6.2°,86.4°±6.4°,94.0°±2.7°,95.6°±3.8°,呈逐渐增大趋势,C3~C4的夹角均小于90°,C5的夹角变异 较大,C6~C7的夹角均大于90°。除了C3与C4,C6与C7外,其余各节段间的差异均有统计学意义(均P<0.05)。以上指标 每节段左右两侧比较,差异均无统计学意义(均P>0.05)。结论:下颈椎椎弓根轴线与椎板平面存在一定的角度关系, 可为临床确定椎弓根螺钉的进钉角度提供参考。  相似文献   
110.
目的 探讨320排CT靶重建联合MRI扫描在孤立性肺结节良、恶性鉴别诊断及肺癌早期诊断中的价值。方法 回顾性分析延安市人民医院320排640层CT低剂量扫描、CT标准靶重建、联合1.5TMRI检查,对临床检出的42例肺内孤立结节(SPN)进行相关诊断研究,分析本项技术是否能够明显提高诊断的准确率。结果 42例可疑孤立性肺小结节中检出42例检出率为100%,常规CT扫描病变检出正确例数28例正确率为66.67%,靶重建后检出正确例数为34例准确率为80.95%,联合CT靶重建及MRI检出正确例数40例,准确率可高达95.42%。结论 CT靶重建技术联合MRI扫描简单易行,患者容易接受,且能提高诊断的准确性。  相似文献   
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