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61.
Bilateral discoid medial menisci is an extremely rare condition of the knee and it can be associated to other pathological findings, including anterior portion cyst formation. We report on the clinical features, radiographic findings, treatment and results of one patient who presented a bilateral medial discoid meniscus combined with posterior portion cyst of the left knee. To the best of the author’s knowledge, this is the first case of bilateral medial discoid meniscus associated with posterior portion cyst formation.  相似文献   
62.
目的探讨环孢霉素A诱发可逆性后部白质脑病综合征(PRLS)的MRI表现。资料与方法回顾性分析1例PRLS的临床资料和MRI表现并复习文献。结果MRI显示PRLS以顶枕叶为主的皮层及皮层下白质病变,病变多呈双侧对称性分布,偶可累及双侧颞叶后部及额叶,T2WI和液体衰减翻转恢复序列(FLAIR)对病变的显示有独特的作用,扩散加权成像(DWI)能够确定PRLS的临床分期。结论PRLS在MRI上具有特征性。MRI表现结合临床资料,对PRLS多能作出正确的诊断。  相似文献   
63.
后颅凹成血管细胞瘤的影像学特点及其诊断   总被引:4,自引:0,他引:4  
目的:探讨成血管细胞瘤的影像学特点。材料与方法:报道14例成血管细胞瘤的CT和MRI所见,分析肿瘤的特点。结果:囊性肿瘤,在MRI上表现为囊性病灶和附壁肿瘤结节;在CT上表现为该典型征象占81.8%。混合性肿瘤3例,在CT和MRI上表现实质性肿块、偏心性囊变和均一显著强化;后者还可见肿瘤旁和肿瘤内血管流空。结论:CT和MRI均是诊断成血管细胞瘤的有效检查方法。成血管细胞瘤的特征性影像学表现是囊肿和突入囊内的壁结节,以及肿瘤的异常显著增强  相似文献   
64.
目的 通过107例胸腰椎骨折伴脊髓损伤病例的治疗,探讨前、后路手术适应证的选择。方法 31例经前路减压植骨,采用Z-Plate等内固定。76例经后路采用短节段椎弓根钉内固定。结果 两组均获得了满意的疗效。结论 选择前或后路手术,应综合考虑脊髓损伤程度、手术时机与技巧、骨折的部位、骨折类型和影像结果等,才能确实做到减压、恢复脊柱序列和坚强固定的目的。  相似文献   
65.
后房型人工晶状体植入术后的超声生物显微镜观察   总被引:6,自引:2,他引:4  
目的:探讨后房型人工晶状体植入术后眼前节结构的改变。确切定位人工晶状体襻的位置。观察人工晶状体襻对于周围组织的影响。方法:白内障摘除及后房型人工晶状体植入术的50名患者(50眼)于术前,术后1周及三个月进行超声生物显微镜观察。结果:术后前房深度,房角宽度押送术前显著增加。人工晶状体中囊袋内植入者36枚(72%)。睫状沟植入者6枚(12%),不对称植入者8枚(16%)。人工晶状体光学部倾斜1眼(2%)。人工晶状体襻推挤虹膜根部2眼(4%)。人工晶状体襻睫状沟侵蚀3眼(6%)。术后1周2眼(4%)眼压升高。皮质少量残留5眼(10%)。结论:囊袋内为后房型人工晶状体植入的理想位置。可保证人工晶状体的良好位置。避免人工晶状体襻对于色素膜组织的干扰及对血-房水屏蔽的损伤,从而减少并发症的发生。  相似文献   
66.
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4.  相似文献   
67.
A clinical study was carried out on nonvital maxillary central incisors to evaluate the incidence of postoperative pain following single-visit root canal treatment using three different instrumentation techniques. Ninety teeth from 78 patients whose ages ranged from 14 to 63 years were selected and divided into three groups. Each group (30 teeth) was prepared by a different coronal-to-apical technique using different instrument movement depending upon the technique employed: modified double-flared, crown-downpressureless and balanced force techniques. No difference was observed in the incidence of postoperative pain among the groups.  相似文献   
68.
Day care is generally accepted in anterior segment eye-surgery. In the Rotterdam Eye Hospital this option was also considered for posterior segment surgery. We were interested in the opinion, of patients on this matter and therefore asked patients, who were admitted for posterior segment eye-surgery, to answer a questionnaire. The major question was: ‘If your physician had given his permission, do you think it would have been possible for you to go home on the evening after surgery?’. Other questions evaluated problems in organising assistance at home and transportation to the out-patient clinic as well as circumstances after the operation, such as pain, nausea, dizziness and anxiety. Eighty-one out of 87 patients responded: 56% answered ‘eyes’ and 44% ‘no’ to the major question. Relating the answer to the major question to medical data and to answers to the other questions, we found organizational problems at home and anxiety to have a statistical significant relation with a negative answer. Clinical factors like age, American Society of Anesthesiologists (ASA)-class, diabetes mellitus (including insulin-dependant), type of anesthesia, time of the day the surgery was finished, duration of surgery, pain, nausea or dizziness were not signficantly related. The number of patients involved in this study, however, is too small to draw conclusions on specific subgroups of patients.  相似文献   
69.
《临床检验仪器学》是一门实践性课程,为改变目前教学中实验场地局限、大型自动化检测仪器缺乏等限制,提出《临床检验仪器学》虚拟仿真教学探索思路。本文基于医学检验应用型人才培养目标,形成检验仪器学单个仪器和综合项目训练的虚拟仿真教学设计与管理举措;构建教学效果评价与质量监控的方法,显著提高学生的自主学习能力和综合实践能力;借助互联网共享优势促进医学检验实验教学的内涵建设。  相似文献   
70.

Background

The effect of the changes in the femoral posterior condylar offset (PCO) on anterior–posterior (AP) translation and internal–external (IE) rotation in cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare the kinematics in CR and PS TKA with respect to the difference in prosthetic design and PCO change through a computational simulation.

Methods

We developed three-dimensional finite element models with the different PCOs of ± 1, ± 2 and ± 3?mm in the posterior direction using CR and PS TKA. We performed the simulation with different PCOs under a deep knee bend condition and evaluated the kinematics for the AP and IE in CR and PS TKA.

Results

The more tibiofemoral (TF) translation in the posterior direction was found as PCO translated in posterior direction for both CR and PS TKA compared to the neutral position. However, the change of the AP translation with respect to the PCO change in CR TKA was greater than PS TKA. The more TF external rotation was found as PCO translated in the anterior direction for both CR and PS TKA compared to the neutral position. However, unlike the TF translation, the TF rotation was not influenced by the PCO change in both CR and PS TKA.

Conclusion

The PCO magnitude was influenced by a postoperative change in the kinematics in CR TKA although a relatively smaller effect was observed in PS TKA. Hence, surgeons should be aware of the PCO change, especially for CR TKA.  相似文献   
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