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61.
Dongrun Tang Guoxiang Song Shimin Cui Lingen Chen Qingbin LiDepartment of Ophthalmology the Second Affiliated Hospital Tianjin Medical UniversityTianjin ChinaDepartment of Neurosurgery Tianjin Huan Hu Hospital 《眼科学报》1994,(3)
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162. 相似文献
62.
肺内小病灶CT表现及其病理基础的研究:附76例分析 总被引:9,自引:0,他引:9
本文对76例肺内小病灶(直径≤3cm)病例进行了CT-病理对照研究。结果表明,短毛刺征,深分叶征、棘状突起征、空泡征、血管集束征,胸膜凹陷征等对于诊断周围型小肺癌有重要临床价值;而尖角征、局限性胸膜肥厚粘连对诊断良性病灶有意义。本文重点讨论了血管集束征的定义,CT表现及病理基础;并就有争议的胸膜凹陷征提出一些粗浅的看法。旨在提高肺内小病灶良恶性诊断的准确率 相似文献
63.
目的研究Stargardt病(Stargardts disease,STGD)的眼底表现和眼底荧光血管造影(fundus fluorescein angiography,FFA)的特征.方法对27例54眼STGD患者进行视力、眼底及FFA检查.结果STGD患者的视力在0.02~0.10者46眼,占85.2%.眼底检查黄斑部均有横径为1.5~3.0 PD大小、呈青灰色并有金箔样反光的横椭圆形萎缩灶,其中15例30眼伴有眼底黄色斑点,占55.6%.FFA检查黄斑部病变为透见荧光,其中8例16眼呈"牛眼"状;22例44眼呈暗脉络膜背景,占81.5%.结论FFA检查在STGD的诊断中极为重要,在病程的不同阶段可有不同FFA表现. 相似文献
64.
OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources. 相似文献
65.
18F-FDG PET/CT对非小细胞肺癌区域淋巴结诊断的假阴性与假阳性研究 总被引:1,自引:1,他引:0
目的探讨18^F-FDG PET/CT在检测非小细胞肺癌(NSCLC)区域淋巴结中出现假阴性和假阳性的因素。方法随机选择手术治疗的NSCLC患者48例,术前1周内行18^F—FDG PET/CT检查,同期行CT增强扫描,术后根据病理检查结果分析PET/CT诊断NSCLC区域淋巴结转移的假阴性与假阳性因素。结果48例患者共切除区域淋巴结313枚,转移淋巴结51枚,PET/CT结果7枚假阴性。8枚假阳性,阳性预测值和阴性预测值分别为85%,97%,高于CT(57%,94%;P=0.002,0.045)。3枚假阴性淋巴结内的癌灶较小;2枚淋巴结短径约为0.4mm,小于PET/CT的空间分辨率;2枚紧邻原发灶的淋巴结,图像无法区分而视为原发灶。8枚假阳性淋巴结为患者在原发病灶基础上并发不同程度的肺部疾病和淋巴结炎症,使其糖代谢率增高。结论假阳性出于(1)淋巴结的短径小于PET/CT的空间分辨率;(2)淋巴结内的小癌灶糖代谢率较低;(3)紧邻原发灶的淋巴结与原发灶无法区分。原发肿瘤合并肺部疾病是导致PET/CT出现假阳性的重要原因。 相似文献
66.
Prevalence of silent myocardial ischemia in asymptomatic individuals with subclinical atherosclerosis detected by electron beam tomography 总被引:3,自引:0,他引:3
Anand D. Vijay Lim Eric Raval Usha Lipkin David Lahiri Avijit 《Journal of nuclear cardiology》2004,11(4):450-457
BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD. 相似文献
67.
Ch. Offergeld J. Kromeier A. Aschendorff W. Maier Th. Klenzner Th. Beleites Th. Zahnert J. Schipper R. Laszig 《European archives of oto-rhino-laryngology》2007,264(4):345-351
Imaging is an essential diagnostic tool in reconstructive middle ear surgery, especially in pre-operative planning. Due to ongoing improvement of imaging quality and development of new imaging techniques like e.g. rotational tomography (RT) post-operative follow-up and immediate evaluation of surgical results may become more important. The aim of this experimental study was to evaluate RT as a new tool for postoperative determination of middle ear anatomy and implant position in temporal bones. RT was performed in ten temporal bone specimen after insertion of different middle ear prostheses concerning material, shape and length (PORP; TORP; Stapes piston). An implantable hearing device (Symphonix Soundbridge®) was also implanted and visualized. For comparison some specimen additionally underwent conventional computed tomography (CT), including the newest technology. Characterization of anatomical structures of the temporal bone using RT was of comparable quality to conventional CT-scans in all investigated specimen while requiring approximately 30% of the CT’s irradiation exposure. Unlike CT the RT showed almost no problems due to metallic artefacts of the implanted prostheses. Furthermore RT enabled a 3-dimensional view of the temporal bone and angle determination of inserted prostheses towards the tympanic membrane and/or the malleus handle. Detailed imaging of the prostheses allowed determination of shape, material and localization within the specimen’s reconstructed middle ear. The new imaging technique of RT allows precise presentation of anatomical structures and middle ear implants in temporal bones. Following these experimental results it will be our future work to evaluate this method in clinical practise. 相似文献
68.
多层螺旋CT尿路造影在尿路梗阻性疾病中的临床应用 总被引:10,自引:1,他引:9
目的探讨多层螺旋CT尿路造影在泌尿系梗阻性疾病诊断中的应用价值。方法对48例泌尿系统梗阻性疾病者,分别进行多层螺旋CT平扫及多时相期CT增强扫描。对增强后各期图像进行相关处理,以不同的三维重建方式获得CTA、CTU影像。所有病例均经临床及手术证实。结果48例中肾脏及输尿管先天畸形者15例;输尿管阴性结石致肾盂输尿管积水者4例;泌尿系炎症者5例;肾及输尿管、膀胱结核6例;外源性压迫导致肾盂及输尿管积水者8例;泌尿系肿瘤者10例。结论多层螺旋CT泌尿系造影对尿路梗阻性疾病的诊断具有很高的应用价值。 相似文献
69.
目的探讨髂静脉多层螺旋CT成像的临床应用价值。方法50例患者行髂静脉多层螺旋CT血管造影,对比剂注射方案为经患侧足背浅静脉以2.5~3.0ml/s注射浓度为150mgI/ml的非离子型对比剂,延迟16~22s后开始扫描。利用多种重建方法进行重建。分析髂静脉的成像质量以及髂静脉疾病的影像特点。结果50例患者均成功完成CT血管造影。其中31例完全阻塞,9例管腔狭窄或见局部充盈缺损,10例完全通畅。图像质量优良率:优24%(12/50),良60%(30/50),差16%(8/50),总体优良率84%(42/50)。结论多层螺旋CT髂静脉成像对诊断静脉疾病有一定的临床价值。 相似文献
70.
Franco Guzzetta 《Child's nervous system》1991,7(8):417-424
Neonatal pathology comprises a large array of cerebral lesions due to ischemic and/or hemorrhagic mechanisms. Pathogenesis, neuropathology, clinical settings in the acute stages as well as short and long-term outcome are discussed. 相似文献