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PubMed1983

The microcomputer-based color image analyzer and its application to histochemistry.

For quantification of histochemical reactions, color image analysis, as well as cytophotometry, is important. However, the extremely large amount of information, usually more than one million bits per image, involved in one microscopic picture of a colored histochemical specimen, when digitalized, has inhibited attempts to develop a more convenient system of color image analysis. Recent advances in microcomputer technology have now made it possible to build, at a reasonable cost, an intelligent color terminal equipped with array-processing hardware, a sufficiently large video random-access memory to represent 4096 colors in each pixel, and packages of machine language subroutines called "macro-commands" in the form of read-only memory that can process color images within a few seconds. This intelligent terminal can easily be controlled by a small personal computer via an IEEE-488 interface bus. The digitalized color image can be stored in and retrieved from a floppy disk. As the macro-commands in this system are controlled by BASIC program through CALLS with parameters, it is highly flexible and adapts readily to the varied needs of histochemists. Reported on herein will be the instrumentation of the microcomputer-based color image analyzer and a few examples of applications of this system to histochemistry: color intensification of cytochemical reactions, quantification of enzyme (e.g., horseradish peroxidase) reaction products, periodic acid-Schiff staining, collagen fibers visualized by Azan-Mallory stain, etc. Possible future applications of this color image analyzer will also be discussed.

Animals↗

PubMed1982

Surgical pathology reports with a portable microcomputer.

A microcomputer reporting system for gross and microscopic surgical pathology is simple and inexpensive, reduces the need for clerical personnel, and saves the pathologist's time in the preparation of reports. Gross descriptions are performatted. A dictionary of microscopic diagnoses is constructed and stored on disks. The diagnosis to be used for a case is selected by a pathologist by number. It is called to a video screen from disk storage by entering the number on the microcomputer keyboard. The diagnosis is edited or expanded for an individual patient while it is on the screen and is printed after changes are made. Each diagnosis contains preentered classification, coding, and filing information, as well as format, medical terminology, and spelling. The system has rapid retrieval and search capability and may be used for patients awaiting frozen-section diagnosis. The system requires fewer clerical personnel in surgical pathology than with free-form reporting.

Computers↗

PubMed1981

An interactive graphic database microcomputer for clinical control in data intensive therapies.

Experiments showed a small computer could improve access to large concentrations of clinical data in renal dialysis and transplantation and enhance the clinical feedback loop which controls substitute renal function. Interactive access adds a sub-loop which allows close adaptation to clinical use. Prototype software was transferred to an LSI-11 microcomputer with 20 Mbyte cartridge discs, multiple remote VDUs and video graphic displays and printer-plotter. Data capture is both manual and by automatic transfer from laboratory computers. Push-button interaction displays clusters of data, including computed functions, as graphs and tables on variable time scales. programmed scans generate data-base analyses. The system reconfigures for individual sites. The microcomputer version has run routinely for a year and proved a practical tool at acceptable cost. Down-time has been small but strongly resented by medical and nursing staff. The system can accommodate 750 patients, but has also been 'stretched' for an oncology laboratory and configured for other specialities.

Computers↗

PubMed1982

Microcomputer as patient educator.

A computer-assisted lesson on general drug knowledge as a patient education tool is described. A drug I.Q. quiz is one of seven microcomputer lessons available to patients in the waiting room of an ambulatory-care clinic. The drug quiz consists of 19 multiple-choice and six true or false questions. After each question, the computer responds with a brief paragraph keyed to the answer selected by the user. If the answer for a multiple-choice question is incorrect, the user can reanswer the question before proceeding. At the end of the lesson, a score is graphically displayed and the user is asked to evaluate the lesson. The computer stores the total number of lessons completed, total scores, number of times each question was answered incorrectly on first and second attempts, number of times each question was answered a second time, and each user's responses to the quiz and evaluation questions. Based on 313 completions of the drug quiz from September 1981 through May 1982, 86% of the users stated that they learned at least something useful, and 72% liked the quiz. The mean (+/- S.D.) number of correct answers on the first attempt was 16 +/- 5; scores improved by an average of 2.5 +/- 2 by reanswering questions. Of 2421 multiple-choice questions answered incorrectly, 62% were reanswered. Of these second attempts, 52% were correct. Item validity scores indicated that the drug quiz serves as a realistic appraisal of drug knowledge. The microcomputer can be an effective medium for patient education.

Computers↗

PubMedDate not supplied

Modular design of microcomputer-based medical instruments.

A modular design approach is effective for developing compact microcomputer-based medical instruments. Each instrument consists of two modules: a microcomputer instrument module that provides data conversion and computing functions and a characteristic module that does analog signal conditioning and includes all interfaces to the environment. The five instruments summarized here are: (a) a portable, battery-operated arrhythmia monitor for ambulatory patients; (b) a physician's computer for remote telephone communication with the portable monitor; (c) a battery-powered arrhythmia monitor/recorder for the operating room; (d) a portable, battery-operated biofeedback device for speech therapy; and (e) a neuromuscular blockade monitor for the operating room.

Computers↗

PubMedDate not supplied

[The use of microcomputers in the processing of complex hemodynamic data].

The use of a low-cost microcomputer in the clinical study of left ventricular diastolic function is described. Both left ventricular filling and compliance were studied by means of the simultaneous recording of left ventricular pressure and an echocardiogram displaying ventricular dimensions. A program was written to calculate ventricular volume every 40 msec and a volume-time diagram was obtained. The raw curve was smoothed with a second degree polinomial. The rate of change of ventricular volume (dV/dt) was obtained. Simultaneous left ventricular volume and pressure were plotted. The diastolic, exponential portion of the pressure-volume loop was used to calculate an index of ventricular stiffness at zero volume. It is concluded that a simple microcomputer, when conveniently programed, is able to perform the time-consuming mathematical operations involved in the clinical assessment of left ventricular diastolic function.

Cardiac Volume↗

PubMed1994

The impact of response options and location in a microcomputer interview on drinking drivers' alcohol use self-reports.

The influence of response options for and location of frequency of alcohol use items in a self-administered microcomputer interview were evaluated in a randomized, experimental study of 296 clients at a west coast treatment site for drinking drivers. Respondents were asked about their frequency of alcohol use in the last 7 days, 30 days, 90 days, and 180 days with three methodological factors randomized: (1) how quantitative the response options were; (2) order of presentation of close-ended response options; and (3) relative placement of alcohol use items in the questionnaire. Results indicate that these methodological factors had minimal influence on self-reports of the frequency of alcohol use. Only two statistically significant effects out of 44 possible were observed. The findings of this study suggest that frequency of alcohol use reports by drinking drivers yield similar information for a range of different response formats and location of the items in a microcomputer interview.

Adult↗

PubMed1993

[Microcomputer image analysis of surface parameters of the optic disk].

103 normal and 86 open-angle glaucoma optic disks were evaluated with the microcomputer image analyser. Except for the diameter and area, all other parameters of the normal disk differed significantly from those of the glaucomatous disk. The cup/rim area ratio in glaucoma was significantly larger, while the cup/disk area ratio was moderately so, indicating that the former was more useful in the early diagnosis of glaucoma. The microcomputer image analyser was reliable and accurate, also capable of processing blurred images from varying exposure and focussing. The quotient between the horizontal and vertical C/D ratios was a relatively stable value with changing glaucomatous cupping.

Adolescent↗

PubMed1993

Planning and implementing a microcomputer local-area network.

Factors to be considered in planning and implementing a microcomputer local-area network (LAN) in a pharmacy department are discussed. Reasons for implementing a LAN include the ability to share data, programs, and peripheral devices among multiple users. The network operating system may be full featured or a peer-to-peer system. Full-featured networks require a dedicated file server but are more powerful and versatile. The file server, if used, is the most important piece of equipment. Factors that affect the choice of a file server are the processor, the bus, memory and speed, the supplier, and the power supply. It is necessary to select network adapters and wiring and to decide whether any of the department's current computer equipment will be used in the network. Decisions must also be made about software. The equipment should be set up by the computer services department or a vendor. Two or more pharmacists must be appointed and trained as supervisors to manage the network, diagnose and correct problems, perform network backup, and guard against computer viruses. Security is a major concern because of the need for confidentiality, the licensure of software for only a limited number of users, and the risk of inadvertent alteration or erasure of data. Network users must be trained to use the system properly. Department managers should consider the need to access the LAN from computers outside the department and the possible incorporation of the LAN into a wide-area network. A microcomputer LAN can provide valuable information services, but careful planning is necessary to avoid pitfalls and to ensure that the network meets current and future needs.

Clinical Pharmacy Information Systems↗

PubMed1997

[The study of DSX-I type microcomputer autometic control injector system].

This paper studies the propulsive force of injector system controlled by 8031 single-chip microcomputer for Medical use By using one 8031 single-chip microcomputer as a microprocessor, the minimal autometic control system is constructed, which turns real-time control into reality. This product is a modern appliance used in diagnostic imaging medicine, in design of which the advanced instrument and electrical machinery are integrated into a unified structure. The clinic data demonstrate that the contrast medium can be injected to patients with rapidly and evenly. Dynamic CT Scanning can be intensified at any site of the body. x-ray dose exposed and lobour intensity to the operator can be decreased greatly, raise working efficiency.

Automation↗

PubMed1989

Microcomputer programs for complex epidemiologic procedures. I. Computation of adjusted rates.

In epidemiological cohort studies one measure of association based directly on incidence or mortality rates is the excess rate. This measure is defined as the excess in these rates between two groups with different exposure experience. At times the computation of these excess rates separately for each of the categories of a risk factor is crucial, as with these rates we can then determine whether the factor exerts a dose-response effect that may implicate a causal relation. Recently an indirect method of standardization has been reported, which computes the excess rates for a factor that are adjusted for the confounding effects of several other factors. The method involves a complex iterative procedure that cannot be carried out easily without the aid of a computer. The objective of this communication is to make available a microcomputer program that has been written to implement this laborious computation. In this pedagogic note the adjustment method is described and the application of the microcomputer program is illustrated.

Epidemiologic Methods↗

PubMed1984

A microcomputer-based package for determination of regional and global cardiac function and coronary hemodynamics.

A multichannel data acquisition package for reduction of systemic and coronary hemodynamic data that utilizes a personal microcomputer is described. The system provides a printout of heart rate, maximal rate of left ventricular pressure development (+dP/dt), maximal rate of ventricular relaxation (-dP/dt), absolute and normalized myocardial segment lengths, the degree of shortening of the segment over the cardiac cycle, systolic, diastolic, and mean coronary blood flow velocities, left ventricular systolic and end diastolic pressures, and systolic, diastolic, and mean aortic blood pressure from six channels of input data. Obtained values are precisely linked to the cardiac cycle. To illustrate the output of this system, data obtained by reading strip-chart records are compared to microcomputer-derived values in conscious, instrumented dogs.

Animals↗

PubMed2003

Noninvasive in vivo monitoring of bone architecture alterations in hindlimb-unloaded female rats using novel three-dimensional microcomputed tomography.

UNLABELLED: We tested a novel microcomputed tomograph designed to longitudinally and noninvasively monitor bone alterations in hindlimb-unloaded female rats at a resolution of 26 microm over a period of 3 weeks. This prototype has a potential to detect three-dimensional trabecular microarchitectural changes induced by growth and unloading. INTRODUCTION: Until now, data concerning structural changes of cancellous bone have only been available after necropsy of animals. In this study, we tested a novel microcomputed tomography (microCT) technique designed to monitor such changes repeatedly at a resolution of 26 microm with an acquisition time of about 10 minutes to map the entire proximal tibial metaphysis. MATERIALS AND METHODS: Four-month-old female Wistar rats were randomized to seven groups of 10 animals to be either tail-suspended or to act as controls. MicroCT and DXA measurements were performed at 0, 7, 14, and 23 days in suspended and control rats. One group was killed at each of these time points, and bone samples were processed for histomorphometry and ex vivo microCT. RESULTS: We verified that a good correlation was obtained between two-dimensional bone parameters evaluated in longitudinal tibial sections either by histomorphometry or microCT and microCT parameters obtained from either in vivo or ex vivo tibias. The longitudinal survey allowed earlier detection of both growth and unloading-related bone changes than the transverse survey. In controls, aging induced denser bones, reorganization of the trabecular network toward a more oriented plate-like structure, and an isotropic pattern. Unloading first inhibited cortical and cancellous bone growth and then induced bone loss characterized by fewer trabeculae, reduced connectivity density, and enhanced structure model index (SMI), revealing a lighter cancellous structure with development of rod-like characteristics. CONCLUSION: We show for the first time that this microCT prototype has a great potential to accurately, repeatedly, reliably, and rapidly investigate alterations of three-dimensional trabecular microarchitecture.

Absorptiometry, Photon↗

PubMedDate not supplied

An application of a microcomputer compiler program to multiple logistic regression analysis.

Microcomputer programs for multiple logistic regression analysis were written in BASIC language to determine the usefulness of microcomputers for multivariate analysis, which is an important method in epidemiological studies. The program, carried out by an interpreter system, required a comparatively long computing time for a small amount of data. For example, it took approximately thirty minutes to compute the data of 6 independent variables and 63 matched sets of case and controls (1:4). The majority of the calculation time was spent computing a matrix. The matrix computation time increased cumulatively in proportion to additions in the number of subjects, and increased exponentially with the number of variables. A BASIC compiler was utilized for the program of multiple logistic regression analysis. The compiled program carried out the same computations as above, but within 4 minutes. Therefore, it is evident that a compiler can be an extremely convenient tool for computing multivariate analysis. The two programs produced here were also easily linked with spreadsheet packages to enter data.

Computers↗

PubMed1978

A microcomputer-based data acquisition and analysis system for CO2 rebreathing studies.

A real-time microcomputer-based data acquisition and analysis system has been developed to automate the measurement of the ventilatory response to CO2 by the rebreathing method. Previous systems acquire the data on-line and then analyze and display the results off-line. The system described here performs all processing on-line and displays experimental results in real-time. The results of 5 min of data acquisition are available for display only 1.5 sec after completion of the experiment. Immediate interpretation of the results of each experiment enable a series of related studies to be performed on the same patient in a short time period. The microcomputer is Digital Equipment Corporation's LSI-11, a low cost 16 bit machine with the basic instruction set of a PDP-11/40. The system has 16 kbytes of memory, a CRT for data display, and a paper tape reader for program loading. Due to the time constraints of real-time processing and the memory constraints of a small system, the software is written entirely in assembler language. The software includes routines for numeric and character input, line and graphical output, linear curve fitting, start of rise detection and floating point computations.

Carbon Dioxide↗

PubMedDate not supplied

Accuracy of liver puncture under US guidance: re-evaluation by microcomputer simulation model.

OBJECTIVE: To evaluate, using microcomputer simulation models, the degree of distortion of the puncture needle in sonograms used during a liver puncture under ultrasound guidance. METHODS: We made a simplified simulation model of the puncture needle passing through the abdominal wall to the target lesion in the liver (cases without ascites), and additionally through ascites between the abdominal wall and the liver (cases with ascites), to evaluate the degree of distortion of the puncture needle in the sonogram. We considered the thicknesses and sound velocities of the abdominal wall and the ascites fluid, as well as the puncture angle, on the degree of distortion. RESULTS: (1) Cases without ascites: The puncture needle displayed on sonogram shifted predominantly anteriorly with a displacement error between 6 mm forward and 1 mm backward and with an angular error between 2.2 degrees forward and 0.1 degree backward when the abdominal wall was muscular, and the pattern of distortion had an inverted S-shape. It was displayed predominantly posteriorly with a displacement error between 14 mm backward and 2 mm forward and with an angular error between 3.7 degrees backward and 1.2 degrees forward when the abdominal wall was fatty, and the pattern was S-shaped. Regardless of the composition of the abdominal wall, when the abdominal wall was thin, the more obtuse the puncture angle was, the larger the shift was, and when the abdominal wall was thick, the more acute the puncture angle was, the larger the shift was. (2) Cases with ascites: (a) Regardless of the quantity and sound velocity of the ascites, the puncture needle shifted predominantly anteriorly with a displacement error between 7 mm forward and 3 mm backward and with an angular error between 3.1 degrees forward and 1.9 degrees backward when the abdominal wall was muscular, and showed the inverted S-shaped pattern. In contrast, it shifted predominantly posteriorly with a displacement error between 17 mm backward and 5 mm forward and with an angular error between 3.7 degrees backward and 3.9 degrees forward when the abdominal wall was fatty, and showed the S-shaped pattern. (b) Regardless of the sound velocity of the ascites fluid and the composition of the abdominal wall, the shift of the puncture needle changed little with differing amounts of ascites. CONCLUSION: It is highly recommended that a liver puncture under US guidance be performed taking into account the pattern of distortion of the puncture needle in each situation.

Artifacts↗

PubMed1987

Diagnosing human malformation patterns with a microcomputer: evaluation of two different algorithms.

SYNDROC, a microcomputer-aided differential diagnostic approach to human malformation patterns, is based on a pseudo-Bayesian algorithm. This means that, for each sign, the frequency of this sign in the general population, its frequency in a particular syndrome, and the frequency of that particular syndrome have to be determined. These parameters are easy to find in common syndromes but tend to be difficult for rare or isolated cases. Thus, we implemented a new algorithm called the "descriptive algorithm," which defines a diagnosis by a set of anomalies all having the same weight. To test this algorithm, we analyzed 100 cases representing 100 different syndromes out of the register of the Division of Medical Genetics, Children's Hospital and Medical Center, University of Washington. The descriptive algorithm was allowed to give 3 sets of diagnoses. In 91% of the cases, this algorithm proposed the correct diagnosis (54% in the first window, 28% in the second window, and 9% in the third window). The number of diagnoses proposed was 18.78 +/- 16.57. The same cases were analyzed with the pseudo-Bayesian algorithm. The concordant diagnosis was proposed in 92% of the cases (55% at the top place, 11% at the second place, and 26% at the third place or beyond). The number of diagnoses submitted was 13.5 +/- 11.04. The combined algorithm gave the correct diagnosis in 96% of the cases. This study shows that the descriptive algorithm is as accurate as the pseudo-Bayesian algorithm in diagnosing malformation patterns, but this level is accompanied by an increased number of proposed diagnoses.

Abnormalities, Multiple↗

PubMed1987

An integrated microcomputer system to maintain a genetic register for Huntington disease.

A microcomputer program has been designed to maintain a large data base for Huntington disease. This program facilitates such data manipulation as adding, altering, retrieving, deleting, and printing pedigrees. The program is self-contained and has a risk-calculating routine built in which automatically provides both the Mendelian and age-modified risks. This package is capable of printing the pedigrees on a simple printer or, alternatively, creates an output-file which can be used with a dedicated plotting program for drawing the pedigrees and their data on a plotter. The program has a routine which can provide a series of statistical data from the register including age-of-onset, diagnosis, death, and other useful information.

Computers↗