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21.
Summary Five aneurysm clips and their respective appliers (Heifetz, Vari-Angle, McFadden, Scoville, and Yaargil) were tested for the production of small metal shards that could provoke a foreign body reaction or increase the risk of a stresscorrosion failure. Pivot and Vari-Angle-McFadden clips produced numerous large shards, the Scoville clip produced a few fine shards, and the Yaargil and Heifetz clips produced none. Metal shard production due to cold metal transfer is attributed to the abrasive mechanical interaction between clips and appliers made from metals with different degrees of hardness.  相似文献   
22.
Summary The authors describe a new method for reproducible, non-invasive fixation of a stereotaxic localizing frame. A localizing system similar to that of Brown-Roberts-Wells for MR can be fixed at the base of the facial skeleton to the upper dental arch by an orthodontic resin plate. Results of trials with CT scan, advantages and disadvantages are discussed.The new fixture could be employed in open surgery and in fractionated radiotherapy.  相似文献   
23.
我院自1982年~1988年共收治13例颈内动脉-后交通动脉瘤。本文就该处动脉瘤的临床诊断、手术入路以及动脉瘤破裂的预防和处理进行了讨论。  相似文献   
24.
目的 介绍后颅窝骨性扩大术治疗Chiari畸形合并脊髓空洞症。方法 该手术分为两种亚术式 ,一种是枕颈固定扩大术 :取自体髂骨 5cm× 10cm ,打磨成“凹”字形。上端为齐头端 ,固定在后颅窝减压窗缘。缺口端为下端 ,固定在枢椎棘突上 ,将扩大的硬脑 (脊 )膜修补筋膜片固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,形成帐篷状 ;另一种是单纯骨性扩大术 :取自体髂骨 6cm× 8cm的梯形骨片 ,并利用较厚的髂骨缘打磨成弧形。植骨片固定在后颅窝减压窗上 ,弧形端构成枕骨大孔后缘。将扩大的硬脑 (脊 )膜修补筋膜片也固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,也形成帐篷状。结果 本组病例随访 2~ 7年 ,术后症状体征缓解总有效率为91.6% ,肌力比以前提高 2~ 3级。结论 该术式比其他治疗Chiari畸形合并脊髓空洞症的术式 ,治疗效果显著 ,疗效切实可靠  相似文献   
25.
The potassium titanyl phosphate (KTP-532) laser has been applied to otologic surgery with a proven record of both safety and efficacy. The aim of this study was to demonstrate the use, safety, and advantages of laser dissection in the surgical treatment of acoustic neuromas. The authors' experience with 111 patients in whom laser surgery was used in acoustic neuroma is presented, with emphasis on surgical technique employed and facial nerve functional outcome. The method of laser dissection did not result in deleterious neurologic sequelae or laser-specific complications. In addition, laser dissection afforded certain advantages to traditional techniques, especially in larger tumors. The facial nerve functional outcome as assessed by the House-Brackmann grading system revealed that 90.2% of small tumors, 72.2% of medium tumors, and 75.0% of large tumors achieved satisfactory (grades I and II) functional results. These results compare favorably with the literature describing nonlaser dissection techniques. The observations and results reported in this article demonstrate the safety of the KTP-532 laser in the posterior cranial fossa, and specific advantages that this technology may offer to the surgical armamentarium of the neuro-otologist are outlined.  相似文献   
26.
A 35-year-old woman had an intradural tumor in the posterior fossa adjacent to the posterior wall of the left pyramidal bone, which was totally removed and histologically diagnosed as a pleomorphic adenoma. Follow-up examination for 2 years showed no recurrence of the tumor. There was no primary lesion in any other gland of the body, and therefore there is no alternative but to conclude a “migration” of some gland cells. The pathogenesis of this tumor remains unclassified.  相似文献   
27.
28.
ObjectiveTo assess which radiological alignment parameters are associated with a satisfactory long‐term clinical outcome after performing lumbar spinal fusion for treating degenerative spondylolisthesis.MethodsThis single‐center prospective study assessed the relation between radiological alignment parameters measured on standing lateral lumbar spine radiographs and the patient‐reported outcome using four different questionnaires (COMI, EQ‐5D, ODI and VAS) as primary outcome measures (level of evidence: II). The following spinopelvic alignment parameters were used: gliding angle, sacral inclination, anterior displacement, sagittal rotation, lumbar lordosis, sacral slope, pelvic tilt and pelvic incidence. Furthermore, the length of stay and perioperative complications were documented. Only cases from 2013 to 2015 of low‐grade degenerative lumbar spondylolisthesis (Meyerding grades I and II) were considered. The patients underwent open posterior lumbar fusion surgery by pedicle screw instrumentation and cage insertion. The operative technique was either a posterior lumbar interbody fusion (PLIF) or a transforaminal lumbar interbody fusion (TLIF) performed by three different senior orthopedic surgeons. Exclusion criteria were spine fractures, minimally invasive techniques, underlying malignant diseases or acute infections, previous or multisegmental spine surgery as well as preoperative neurologic impairment. Of 89 initially contacted patients, 17 patients were included for data analysis (11 males, six females).ResultsThe data of 17 patients after mono‐ or bisegmental lumbar fusion surgery to treat low‐grade lumbar spondylolisthesis and with a follow‐up time of least 72 months were analyzed. The mean age was 66.7 ± 11.3 years. In terms of complications two dural tears and one intraoperative bleeding occurred. The average body mass index (BMI) was 27.6 ± 4.4 kg/m2 and the average inpatient length of stay was 12.9 ± 3.8 days (range: 8–21). The long‐term clinical outcome correlated significantly with the change of the pelvic tilt (r s = −0.515, P < 0.05) and the sagittal rotation (r s = −0.545, P < 0.05). The sacral slope was significantly associated with the sacral inclination (r s = 0.637, P < 0.01) and the pelvic incidence (r s = 0.500, P < 0.05). In addition, the pelvic incidence showed a significant correlation with the pelvic tilt (r s = 0.709, P < 0.01). The change of the different clinical scores over time also correlated significantly between the different questionnaires.ConclusionsThe surgical modification of the pelvic tilt and the sagittal rotation are the two radiological alignment parameters that can most accurately predict the long‐term clinical outcome after lumbar interbody fusion surgery.  相似文献   
29.
【摘要】 目的:探讨腰椎椎体间融合内固定术后融合器脱出(cage retropulsion,CR)的危险因素。方法:回顾性分析2017年9月~2021年9月在我院因腰椎椎体间融合内固定术后CR行翻修手术的17例患者,其中男13例,女4例,年龄63.7±9.9岁,纳入CR组。根据相同的融合及固定节段、初次手术时间(±1年)、性别、年龄(±2岁)在无融合器脱出及移位的患者中按照2∶1的比例进行配对共匹配34例作为对照组,其中男26例,女8例,年龄65.2±10.2岁。CR组初次手术平均固定节段数为1.8±0.8个,融合节段数为1.5±0.6个;发现CR距离初次手术时间为7个月(0.75~132个月);17例患者中单个节段CR 15例,两个节段CR 2例。在两组患者术前全脊柱X线片上测量腰椎前凸角(lumbar lordosis,LL)、骨盆倾斜角(pelvic tilt,PT)、骶骨倾斜角(sacral slope,SS)、骨盆入射角(pelvic incidence,PI)、腰椎侧位X线片上测量病变节段椎间高度(disc height,DH)、屈伸位X线片上测量椎间隙活动度(range of motion,ROM);通过术前腰椎CT检查测量腰椎椎体CT值;通过腰椎MRI检查定义椎间盘形态;在术后即刻腰椎X线片上测量融合器位置(融合器后缘标记线到下位椎体后上缘的距离与下位椎体上终板前后径的比值)。采用配对样本t检验的方法对两组间资料进行单因素分析,对单因素分析有统计学意义的参数进行Logistic回归分析,寻找CR的独立危险因素。结果:CR组椎体CT值小于对照组(124.8±39.7 vs 147.7±38.2, P=0.011),术后即刻X线片上融合器位置较对照组更靠后(0.15±0.09 vs 0.31±0.07, P<0.001);两组间术前LL(40.8°±12.9° vs 42.4°±7.5°,P=0.717)、PT(19.6°±7.1° vs 17.1°±6.7°,P=0.356)、SS(27.7°±6.5° vs 31.0°±4.3°,P=0.144)、PI(44.3°±13.8° vs 44.7°±13.9°,P=0.926)、DH(10.1±2.4mm vs 8.8±1.4mm,P=0.066)、ROM(4.3°±2.8° vs 4.4°±2.2°,P=0.950)、梨形椎间盘比例(33.3% vs 21.4%,P=0.40)均无统计学差异。Logistic回归分析结果提示椎体CT值低(骨质疏松)(OR=0.975,P=0.043)和融合器位置靠后(OR=28.393,P=0.003)是CR的独立危险因素。结论:骨质疏松与融合器放置靠后是后路腰椎椎体间融合术后CR的危险因素。  相似文献   
30.
Osseodensification is a new method of bone instrumentation for dental implant placement that preserves bulk bone and increases primary implant stability, and may accelerate the implant rehabilitation treatment period and provide higher success and survival rates than conventional methods. The aim of this retrospective study was to evaluate and discuss results obtained on immediate implant placement with immediate and delayed loading protocols under Osseodensification bone instrumentation. This study included private practice patients that required dental implant rehabilitation, between February 2017 and October 2019. All implants were placed under Osseodensification and had to be in function for at least 12 months to be included on the study. A total of 211 implants were included in the study, with a 98.1% total survival rate (97.9% in the maxilla and 98.5% in the mandible). For immediate implants with immediate load, 99.2% survival rate was achieved, and 100% survival rate for immediate implant placement without immediate load cases. A total of four implants were lost during this period, and all of them were lost within two months after placement. Within the limitations of this study, it can be concluded that Osseodensification bone instrumentation provided similar or better results on survival rates than conventional bone instrumentation.  相似文献   
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