Spectral analysis of Doppler ultrasonic flow signals by a personal computer

This paper describes a method of performing spectral analysis on Doppler acoustical signals from peripheral blood vessels with the use of an Apple II plus personal computer.

Digitization is accomplished with a commercially available analog-to-digital converter. The data are transformed with a fast Fourier technique, and the resultant information is plotted by an inexpensive X-Y plotter and/or on a television receiver.     

Single-fibre electromyography with a personal computer

A single-fibre electromyography measuring unit based upon a personal computer (Apple II) and a special triggering unit is described. Its compact size facilitates its use online, next to the patient. It is a relatively cheap system, and can be handled by one investigator and a nurse. Operation is simple, and error messages are provided. Investigation of a patient consists of measuring the time of occurrence of action potentials in up to 20 trains of complex motor unit action potentials (MUAPs). One train may consist of up to 170 MUAPs, each comprising a maximum of four single action potentials (spikes). Triggering is performed with a special unit after an initial spike, triggering at an adjustable level is only possible within an adjustable time window. This feature reduces false triggerings and allows selection of a part of a complex MUAP. Interval analysis by the computer also reduces processing of MUAPs originating from other motor units. Computed are the mean consecutive difference (MCD) values of the jitter, the variance, the percentage of blockings and the number of relevant intervals. Scatter plots can be displayed and printed of the raw data, the consecutive differences or the interpulse intervals (IPI) against the interdischarge intervals (IDI). Suspicious data may be rejected by manipulation of graphical cursors. If a MUAP consists of at least four spikes, a test can be carried out whether there is a neurogenic variability cause concomitant jitter. The system has been evaluated over the last two years in the EMG department of the Academic Hospital, Utrecht, The Netherlands.     

Development of a computerized EEG imaging system with a personal computer

The authors developed a computerized electroencephalography imaging system with an IBM PC AT. The EEG signals amplified with a 16 channel EEG machine were digitized at 51.2 Hz (512 samples per epoch). The shifted DC potential and 60Hz artificats were removed by a high pass filter and 60Hz notch filter. A window function consisting of a 10% cosine taper was obtained by weighting the points at either end of the epoch by a cosine bell. A fast Fourier transform was applied to every epoch and the power spectrum estimates were computed in 0.39 Hz steps. The activity estimates for the delta, theta, alpha and beta bands were computed by summimg adjacent values. The outline of the top-down maps was formed from a series of sagittal cuts, then 32 electrodes were placed on the map. A file was created which contained a table of weighting parameters for calculating the interpolated values for every point within the outline. Each weight was in inverse linear proportion to the distance of the pixel to the nearest four electrodes. The map was finally generated with computation of the spectral EEG in each pixel according to the weighting parameter. The functioning of this system was tested with a functional generator and a human subject.     

Quality control in medicine. Analysis of death certificate entries with a personal computer

Important information obtained from autopsies may be statistically evaluated by means of decentralized data processing, using the personal computer. A method for precise evaluation of death certificates against autoptic findings is described in this paper. This computer-assisted approach facilitates statistical analysis of mortality and supports the accuracy of clinical diagnoses.     

Optical measurement of cardiac rhythm using a personal computer with telediagnosis possibilities

A system that enables the automatic measurement of cardiac rhythm and the quantity of oxygen in the blood has been designed, constructed, and patented. Equipped with the appropriate software, this system registers this information and represents it numerically, in the form of a graph, which can then be printed as a detailed record of cardiac rhythm. This system aids in the determination of cardiac pathologies, and also enables the information to be sent to medical professionals to perform telediagnosis. The apparatus is based on the measurement (sampling) of noninvasive medical parameters. The apparatus is intended to cover a broad range of requirements and needs, as can be used by medical professionals (to detect pathologies related to the pumping and circulation of blood in the body) as well as by lay people who might wish to monitor or gain information concerning their cardiac rhythm and the general functioning of their heart. Thus, the system is designed to be clear and concise in its information as well as easy to use, especially for people unrelated to the medical profession. The way to constructing this system is explained in detail.     

Three-dimensional planning of remote gamma-therapy on a personal computer

Conclusions A three-dimensional system for radiation planning of remote gamma-therapy has been developed. The system is of a modular type, and it might be of interest to various specialists (radiologists, roentgenologists, oncologists, undergraduate and postgraduate students, etc.). The system allows archiving of stored information about patients and display of roentgenograms, computer tomograms, and magnetic resonance images. It also provides metric analysis of acquired data.The system is supposed to allow practical radiologists to develop three-dimensional planning of remote gamma-radiation therapy, thus, significantly increasing quality and efficacy of medical treatment of oncological patients.Russian State Medical University and N. N. Burdenko Scientific-Research Institute for Neurosurgery, Moscow. Translated from Meditsinskaya Tekhnika, No. 2, pp. 3–8, March–April, 1993.     

Color flow Doppler: a useful instrument in the diagnosis of funic presentation.

Color Doppler sonography offers the opportunity to evaluate the umbilical cord and to study blood velocity wave forms within the cord. Funic (cord) presentation can be diagnosed unequivocally with color Doppler sonography. Because funic presentation is likely to be the harbinger of cord prolapse, the morbidity and mortality associated with cord prolapse can be prevented if funic presentation is diagnosed before membrane rupture. This article describes the first case in the obstetric literature of funic presentation diagnosed with color Doppler sonography. The potential complications associated with cord prolapse were avoided with a cesarean section.     

Handheld computer use in a family medicine clerkship.

PURPOSE: The objectives of this study were to track students' use of medical and nonmedical personal digital assistant (PDA) software and to obtain students' ratings of the usefulness of PDAs in a family medicine clerkship. METHOD: During the academic year 2001-02, third-year clerkship students at the Northeastern Ohio Universities College of Medicine were loaned PDAs equipped with company-installed software, such as a date book and address book. Additional software was installed (Griffith's 5 Minute Clinical Consult, ePocrates qRx, ePocrates qID, iSilo, HanDBase, MedCalc, and Application Usage). Pre- and post-orientation questionnaires and a post-rotation evaluation measured students' comfort level, the perceived usefulness, and ratings of programs on their PDA. Application Usage tracked the number of minutes and times students used each software program. RESULTS: Eighty-five students completed the study. They rated ePocrates qRx and Griffith's 5 Minute Clinical Consult the most useful medical software programs. PDAs were rated as "almost always" enhancing the clerkship experience. Students reported the PDA altered the way they accessed clinical information and that every few days it helped them understand a clinical discussion. Experience with computer technology was correlated with PDA use. CONCLUSIONS: This study objectively demonstrates clerkship students' use of PDA resources. Students' use mirrors their assessment of the value of the software. Although PDAs and software programs can be an expense, it is a worthwhile educational resource as evaluated by the medical student.     

Color Doppler Imaging of the orbital vessels

In ophthalmologic ultrasonography, Color Doppler Imaging (CDI) is a valuable method for detecting hemodynamic information in the central vessels of the retrobulb (ophthalmic artery, central retinal artery and internal carotid artery, etc.) and complementing the diagnosis of eye and eyeground view. Especially in diabetics, if orbital peripheral vascular resistance goes up with progress of diabetic retinopathy, the ophthalmic artery flow velocity wave form undergoes remarkable change, and the ratio of systolic mean velocity to diastolic mean velocity (mean S/D ratio) increases. On the other hand, if carotid obstruction and carotid advanced stenosis arise in sphagitides by the progress of macroangiopathy, the ophthalmic artery becomes the collateral pathway. Then, the flow directional reversal responsible for the collateral pathway is recognized and enters cerebral circulation and, as a result, the ophthalmic artery causes a fall in retinal circulation. As mentioned above, CDI in the ophthalmologic field plays a useful role not only in eyeground management, but in elucidation of the mechanism of ocular ischemic syndrome.     

彩色多普勒对移植肝脏的血流动力学监测

采用彩色多普勒超声对移植肝血流动力学进行监测，了解肝移植前后肝脏血流动力学变化。观察与推测血管吻合口的通畅程度，寻找与排除并发症的存在，进而判断移植肝成活度及预后，就本院近期6例同种原位肝移植术后的移植肝血流进行检测，观察动、静脉吻合口的通畅情况及门静脉与肝动脉血流动力学改善程序，6例移植肝脏周围未见液性及实性异常回声，肝内实质及管道回声与血流方向，速度正常，在24个吻合口中，5例门静脉吻合口通过，1例门静脉吻合口稍窄，局部血流速度稍快，12个腔静脉吻合口中11个吻合口通畅，1个下腔静脉肝下段吻合口稍窄，6个肝动脉吻合口以远的肝动脉血流速度，阻力指数正常，肝移植是解决门脉高压的根本办法，彩色多普勒超声是移植肝血流动力学变化无创检测最佳手段。     

彩色多普勒对高度近视眼的微循环血液动力学研究

目的 :研究高度近视眼的微循环血液动力学变化。方法 :应用彩色多普勒对 3 8只高度近视眼和 40只正常眼的眼动脉、睫状后短动脉、视网膜中央动脉的收缩期最大流速、阻力指数结果进行对比分析。结果 :高度近视眼组和正常组的血流参数比较 ,睫状后短动脉和视网膜中央动脉的收缩期最大流速和阻力指数均低于正常组有显著差异 ( P<0 .0 1)。眼动脉血流参数无明显差异 ( P>0 .0 5 )。结论 :高度近视眼的睫状后短动脉、视网膜中央动脉的血流参数均明显降低 ,彩色多普勒有可能应用于眼的微循环的血液动力学的病理改变形成机制的研究。     

Generation of dynamic random-element stereograms in real time with a system based on a personal computer

A new system capable of generating static and dynamic random-element stereograms is designed and implemented. The stereogram is composed of a rectangle that can be varied in size, element density, orientation, and horizontal and vertical disparties, and can be swept at several velocities. The system is based on an inexpensive personal computer (Amiga 500), designed to work as a slave system under the control of a host computer (e.g. any personal computer). A colour monitor or two black and white monitors are suitable display devices to view the stereograms. This system is used to perform psycophysical experiments in humans and neurophysiological experiments in behaving monkeys, with the purpose of studying depth perception and binocular vision.     

阴道彩超与腹部彩超诊断异位妊娠的临床价值分析

目的 评价阴道彩超和腹部彩超诊断异位妊娠的临床价值。方法 分别应用腹部彩超和阴道彩超对我院妇科2016年10月~2017年6月收治的73例异位妊娠患者实施诊断,比较两种方法各超声表现的检出率、各种分型异位妊娠的检出率及与病理结果的符合率。结果 超声表现方面,腹部彩超诊断异位妊娠中附件包块、宫内假孕囊、卵黄囊、胎心、胚芽的检出率均低于阴道彩超诊断的检出率,差异均具有统计学意义（P＜0.05）。异位妊娠分型方面,腹部彩超的流产型异位妊娠、破裂型异位妊娠、未破裂型异位妊娠检出率分别为21.92%、13.70%、15.07%,低于阴道彩超的诊断结果（38.36%、26.03%、31.51%）,差异均具有统计学意义（P＜0.05）。腹部彩超诊断结果与病理结果的符合率低于阴道彩超,差异有统计学意义（P＜0.05）。结论 腹部彩超和阴道彩超诊断异位妊娠均具有较高的准确率,与腹部彩超比较,阴道彩超能够获得的影像学信息更多,应用价值较高。     

彩色多普勒血流显像与彩色多普勒能量图在恶性滋养细胞肿瘤的应用

目的探讨彩色多普勒血流显像(CDFI)及彩色多普勒能量图(CDE)在恶性滋养细胞肿瘤(GTD)早期诊断及化疗监测中的应用价值.方法对20例GTD进行CDFI、CDE检测,观察其血流情况及用PD检测病变区血流速度,测算RI值.结果CDFI显示病变区血流异常丰富,CDE显示更丰富的血流信号.PD检测出低阻血流,RI=0.41±0.07,化疗前后相比CDFI、CDE和PD改变明显,RI值差异有非常显著性意义(p<0.01).结论CDFI、CDE对恶性滋养细胞肿瘤诊断及观察疗效均有十分重要的价值.     

EEG data filing system with personal computer and magneto-optical disc

We established a new computerized EEG filing system, in which an EEG machine was connected to an EEG filing unit which consisted of a personal computer with a 32 bit CPU, 18 channel analog -to-digital and digital-to-analog converters, and a magneto-optical disc driver. This system has the following merits. The system was space-saving, the space required to store the EEG data, being only 1/500 of that required for storing EEG record. Though the system had two independent EEG filing units, our original file configuration enabled us to have access to all of the recorded EEG data anytime for more than 10 years. The system enabled us to display EEG data continuously on the high resolution CRT, just as if turning the page of an EEG record paper, and through the quick scanning, enabled us to view the entire EEG pattern. Furthermore, the system enabled us to conduct reliable digital analysis for EEG data by entering the EEG data without artifacts into a data processor after confirmation on the display. In the system, we used data files with the MS-DOS operating system. This enabled us to analyze the data obtained by a personal computer operating on other systems, by transferring the data to a floppy disc operating on our system. Our EEG filing system allows quick access to data as well as mass data storage.