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121.
 目的   评估CT引导经皮穿刺活检对脊柱病变的临床诊断价值。方法    回顾性分析行CT引导经皮穿刺活检并经手术病理和(或)临床随访证实的127例脊柱病变的病例资料,活检部位包括颈椎5例、胸椎50例,腰椎58例、骶椎14例,所有活检标本送病理科进行组织病理学检查。所有病例通过后续手术病理和(或)临床随访确定最终诊断,以此为标准评价穿刺活检病理诊断的准确率;计算不同影像学诊断的准确率、敏感性及特异性,并与穿刺活检病理诊断相比较。结果    127例穿刺活检术活检成功率为99.21% (126/127),所有患者均未发生严重并发症。穿刺活检获得明确诊断119例(恶性病变56例,良性病变63例),7例无法明确诊断或出现阴性结果。经随访和(或)手术病理证实,最终确诊127例中良性病变67例,恶性病变60例。穿刺活检总的诊断准确率为92.06%(116/126),恶性和良性病变诊断准确率分别为93.33% (56/60)和90.91% (60/66),差异无统计学意义(χ2=0.03,P=0.863);穿刺活检术前单纯CT、MRI和核医学影像检查对脊柱病变的诊断准确率分别为69.54%、68.48%和75.64%,均明显低于CT引导下穿刺活检诊断准确率。结论    CT引导下经皮脊柱穿刺活检具有安全、有效、微创、准确率高等特点,可弥补单纯影像学诊断准确率偏低的局限性,是确诊脊柱病变的良好活检方式。  相似文献   
122.
AIM: To investigate the diffusion changes in both the optic nerve and optic tract in orbital space-occupying lesion patients with decreased visual acuity, and its clinical significance using probabilistic diffusion tractography (PDT). METHODS: Twenty patients with orbital space-occupying lesions and 25 age- and gender-matched healthy persons were included. All patients and controls underwent routine orbital magnetic resonance imaging and diffusion tensor imaging (DTI), using a 3.0T magnetic resonance scanner (Trio Tim Siemens). After the image data were preprocessed, each DTI parameters of the optic nerve and optic tract was obtained by PDT, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). The asymmetry index (AI) of each parameter was calculated. Compared the parameters of the affected side optic nerve and ipsilateral optic tract with the contralateral side by paired sample t-test; compared AI of parameters of optic nerve and optic tract between the patient group and the control group by independent sample t-test. Patients were divided into three subgroups according to the low vision grade standard of WHO, compared the FA and AI of FA between the three subgroups by single factor variance analysis. RESULTS: The affected side optic nerve presented significantly decreased FA, increased MD, AD, and RD values compared to the unaffected side (P<0.05). The AI of FA, MD, AD, and RD of optic nerve in the patients was significantly higher than that of the controls (P<0.05). The comparison results of the optic tract showed that there was no significant difference between the patient group and control group in terms of the bilateral optic tracts in patients (P>0.05). The AIs of the FA value of the optic nerve in the eyesight <0.1 subgroup was significantly higher than that in the other groups (P<0.05). CONCLUSION: FA, MD, AD, and RD of the affected side optic nerve of the orbital space-occupying lesions have significantly changed, the FA value is the most sensitive. The PDT could be a useful tool to provide valid quantitative markers of optic nerve injuries and evaluate the severity of orbital diseases, which other examinations cannot be acquired.  相似文献   
123.
目的:观察和分析磁共振颅表定位网对颅内小病灶进行术前定位的治疗效果方法:应用磁共振颅表定位网定位技术,对26例颅内小占位病灶进行术前定位,然后进行小骨瓣开颅手术,将颅内小病灶显微镜下全切。结果:26例患者经过定位网定位后,准确而微创地切除了病灶,而且诊治过程顺利,无严重并发症发生。结论:磁共振颅表定位网具有定位准确、安全等优点,是重要的神经外科微创诊疗技术。  相似文献   
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The relationship between clinical symptoms and neurocognitive impairment has been a growing interest in the field of schizophrenia research. We review the empirical evidence for whether some schizophrenia symptoms can be viewed as expressions of disordered executive functioning. A specific focus of our review is Frith’s (1992) neurocognitive theory of negative symptoms, and whether this theory is supported by studies of executive functioning in schizophrenia. The current trend towards viewing executive functioning in terms of fractionable cognitive processes is discussed. Difficulties with traditional clinical measures (e.g. the Wisconsin Card Sorting Test; WCST) in separating these processes are highlighted. Neurocognitive studies of schizophrenia are then reviewed in terms of this fractionated view of executive processes. We conclude that a more specific approach to executive functioning deficits in schizophrenia using more selective measures is needed before stronger conclusions can be drawn about their relationship to clinical symptoms.  相似文献   
126.
BACKGROUND: Laser scar revision has been an effective method for improving several aspects of scarring through ablative and non-ablative sources. The 585-nm pulsed dye laser (PDL) is an important non-ablative instrument for reducing scar bulk and symptoms. OBJECTIVE: To describe the use of a 585-nm PDL for the treatment of a retracted and atrophic facial scar. METHODS: We report the case of a 26-year-old patient who presented with a retracted facial scar following surgical excision of an aggressive benign tumor. Treatment was carried out using the 585-nm PDL. RESULTS: Treatment of the scar using two low-level PDL therapies significantly altered the appearance of the scar and augmentation of the retracted defect was avoided. CONCLUSION: Treatment of this retracted and atrophic facial scar with the 585-nm PDL was very effective and safe.  相似文献   
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王家飞  赵卫东 《医学综述》2014,(22):4074-4076
阴道上皮内瘤变(Va IN)是一种不常见的无症状的癌前病变。其病因和演变成浸润性癌的潜在原因尚不清楚。其发病率虽较低,但仍会威胁患者的生命健康,特别是高级别的病变。Va IN经早期治疗后常常可以转归,但由于高危的复发及进展可能需长期谨慎的随诊。目前该病无标准的治疗指南,且每种治疗方法都有其优缺点,因此就每例患者的特点而选择恰当的方法显得尤其重要。  相似文献   
130.
本文报告1例因牙齿根面畸形导致严重根尖病变及牙周破坏的牙周牙髓联合病变的左上侧切牙,瘘道长期不愈,腭侧窄而深牙周袋,严重根尖病变及牙槽骨垂直吸收。通过显微根管治疗、根尖手术、引导牙周组织再生术治疗,实现了控制根尖及牙周感染,达到了保留患牙的目的。  相似文献   
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