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101.
102.
BACKGROUND: Somatosensory evoked potentials (SSEPs) have long been recognized as an excellent tool for detecting neural and vascular compromise during vascular, neurosurgical and orthopedic procedures. SSEPs have the ability to localize, central versus peripheral, the area of compromise. Many surgeons use only lower-limb SSEP monitoring when performing lumbar spinal surgery. The upper extremities are usually not monitored during such procedures, and monitoring oxygen saturation does not detect neural compromise. PURPOSE: To report that the expanded use of SSEP monitoring during surgery can be beneficial in detecting peripheral ischemia or neural compromise resulting from positioning. STUDY DESIGN: Three case reviews of orthopedic spine surgeries where SSEP monitoring provided early warnings of vascular and neural compression. METHODS: The cases review three different lumbar procedures in which evidence of peripheral ischemia and nerve compression were detected by SSEP monitoring. RESULTS: By the use of upper- and lower-extremity monitoring during lumbar procedures, early detection of ischemia and nerve compression were noted intraoperatively. These changes prompted examination of the patient and repositioning to correct the ischemia or compression. The repositioning in these cases corrected the problem, and no lasting effects were found. CONCLUSIONS: Including SSEP monitoring of the bilateral upper extremities should be considered during lumbar spinal procedures. Such monitoring can be offered for a slightly increased expense and only minimal time delay to place the additional required electrodes by the technician. As a direct result of the early warning of the SSEP monitoring, we were able to avoid potential ischemic injuries and improve patient outcomes. 相似文献
103.
Endorectal surface coil MR imaging of prostatic carcinoma with the inversion-recovery sequence 总被引:1,自引:0,他引:1
F Parivar V Rajanayagam V Waluch R T Eto L W Jones B D Ross 《Journal of magnetic resonance imaging : JMRI》1991,1(6):657-664
The value of inversion-recovery (IR) sequences in the diagnosis and staging of prostatic carcinoma with magnetic resonance (MR) imaging was studied. Twenty-six patients with carcinoma of the prostate were imaged at 1.5 T with an endorectal surface coil and with a variety of IR sequences and a set of spin-echo (SE) sequences for comparison. Ex vivo prostate specimens were imaged again at the same field strength. The two images were correlated with histologic sections. Cancer was identified with MR imaging in 96% of patients. Of the tumors more than 4 mm in diameter, 87% were identified on T2-weighted SE images, whereas only 26% were identified on IR images. However, IR images may be more useful in local staging of carcinoma. Gross capsular infiltration was present in only two patients; however, it was detectable (and excluded in five other patients) by means of IR images. It was not detectable on SE images. The high quality of images obtained with the endorectal coil was confirmed. The authors conclude that addition of the IR sequence to MR imaging with the endorectal coil may improve the usefulness of this examination. 相似文献
104.
105.
J C Stevens A S Jones J Lancer E Beckingham 《Journal of medical engineering & technology》1987,11(6):278-281
The determination of nasal airway resistance by the technique of anterior rhinomanometry is made difficult by several factors. Among these are the variability in the breath by breath measurement of airflow and pressure, the effect of under or over breathing, and the ability to produce a smooth transition between inspiration and expiration during which period the measurements are made. To overcome some of these problems a standard procedure has been developed (in our laboratory) for active anterior rhinomanometry. The nasal resistance is calculated from the mean of three sets of three readings with a rest interval between each set. To enable the procedure to be carried out with consistency it has been implemented on a BBC microcomputer. This enables a breathing guide to be provided for the subject, as well as providing a display of each flow pressure curve, a display of the mean curve, plus and minus one standard deviation, and the calculation of left, right and total nasal airway resistance. 相似文献
106.
107.
Smoking habits in insulin-treated diabetics in Nottinghamshire (UK) and clinic-attending diabetics in Nottingham have been analysed. Compared with the general population, the prevalence of current cigarette smoking is significantly less (p less than 0.001) in both diabetic men and women older than 50 years. Fewer diabetic men over 60 years have ever smoked than in the general population (p less than 0.001) but this finding does not apply to diabetic women. While intervention probably plays some part in this lower prevalence, the most likely explanation is the multiplicative effect of both smoking and diabetes to produce high mortality risks. Actuarial analysis of insulin-treated clinic attenders diagnosed after 1970 showed that at most 14% (95% confidence interval [Cl] 9-18%) of the 183 who smoked at diagnosis had given up 5 years later while a minimum of 8% (95% Cl, 6-11%) of the 313 who were non-smokers had started smoking. Information about the patterns of smoking in patients with chronic disease is incomplete and it appears that too little is being done in clinical services which provide long-term management for these patients to either discourage smoking or determine why some patients give up smoking but others do not. 相似文献
108.
L V Reznik E M Myazina E I Shakchmatova S P Gambaryan V K Brovtsyn Y V Natochin M M Jones 《British journal of cancer》1991,63(2):234-236
Two hydroxyl containing dithiocarbamates, sodium N-methyl-D-glucamine dithiocarbamate (NaG) and sodium dihydroxyethyl dithiocarbamate (NaY) have been examined as agents for the control of the renal dysfunction in rats given cisplatin. Of these, NaG was found to be the more effective in controlling such renal dysfunction when administered at 1 and 3 h after 5 mg cisplatin kg-1, i.p. Renal function was examined 5 days after the administration of cisplatin by measurement of serum and urinary levels of creatinine and urea, creatinine clearance, serum and urinary levels of Na+, K+, Mg2+, Ca2+, as well as the concentrations of these ions in the renal medulla and cortex. Treatment of rats given cisplatin with NaG at 1 and 3 h post cisplatin resulted in indices of renal function which were not significantly different from those of animals which had received no cisplatin. The sole difference was found to be a slight increase in renal cortical Na+ concentration. 相似文献
109.
A young woman was bitten on the shoulder by a female Steatoda nobilis spider, in Worthing on the south coast of England. She noticed intense radiating pain, local sweating (indicating parasympathetic stimulation) and feverishness. This immigrant species from the Canary Islands has established itself along the south coast of England in recent years. Like the related Mediterranean species S. paykulliana, S. nobilis may be of medical importance and deserves further study. 相似文献
110.
背景日常生活中,自闭症患者核心社交不足的表现比外在实验任务中的表现要显著得多。为了使实验测量符合临床观察,我们介绍一种新方法,即在一个模拟日常需要的设置中采用社会监测的定量非典型性策略。把增强的社会生态有效性对这两组的影响最大化,同时评估实验变量相对的社会能力成果测量的效用。方法在观察社会场景时,用眼睛追踪技术测量目测定位,对象是15个有感知能力的自闭症男人和15个年龄、性别与言语IQ相称的控制主体。我们编码4个可靠的定位区域:嘴、眼睛、身体和目标。统计学分析把这两组定位在兴趣区域上的时间和社会能力成果测量作了比较。(比如日常社会调整和自闭症患者的社会症状的标准化测量)结果在四个区域中都观察到这两组间的重大不同。自闭症的最佳预报器是眼睛区域上的定位时间减少。定位在嘴巴上还是定位在目标上与社交机能紧密相关:增加对嘴的注意预示着改良的社会适应性和较少的自闭症社会损伤,而花更多时间注意目标则预示着相反的关系。结论在观察自然社会情形时,自闭症个体表现出社会视觉追击的反常模式,即眼睛不再那么突出,而嘴巴、身体和目标却越加突出。定位在嘴巴和目标(而不是眼睛)上的时间是社会能力的强有力指示器。 相似文献