New hospital system option: distributed data.
In a distributed network, minicomputers in a hospital's functional areas operate independently or interactively to meet their areas's data needs.
Computers↗
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Diagnosis of alcoholic cirrhosis with the right-to-left hepatic lobe ratio: concise communication.
Since scans of cirrhotic livers commonly show a reduction in size and colloid uptake of the right lobe, a quantitative measure of uptake was made using a minicomputer to determine total counts in regions of interest defined over each lobe. Right-to-left ratios were then compared in 103 patients. For normal patients the mean ratio +/- 1 s.d. was 2.85 +/- 0.65, and the mean for patients with known cirrhosis was 1.08 +/- 0.33. Patients with other liver diseases had ratios similar to the normal group. The normal range of the right-to-left lobe ratio was 1.55-4.15. The sensitivity of the ratio for alcoholic cirrhosis was 85.7% and the specificity was 100% in this patient population. The right-to-left lobe ratio was more sensitive and specific for alcoholic cirrhosis than any other criterion tested. An hypothesis is described to explain these results.
Colloids↗
Visual field changes in ocular hypertension. A computer-based analysis.
A minicomputer system has been developed to digitize and store visual field data. In 110 cortiocosteroid-nonresponding subjects aged 10 to 75, the area of the i4e and i2e isopters and of the blind spot changed linearly as a function of age. Within this population the same visual field parameters were randomly distributed with respect to intraocular pressure. In 32 cortiocosteroid responders (increase in intraocular pressure to over 31 mm Hg after topical administration of corticosteroids) with normal visual fields, the central visual field area (i2e isopter) was reduced as a nonlinear function of IOP. Increases in IOP in excess of 8 mm Hg were required to produce significant mean reductions in central visual field area.
Adolescent↗
Computer processing of visual field data. I. Recording, storage, and retrieval.
A minicomputer system has been developed to provide real-time management of visual field data. Records of a large population of patients with glaucoma in a university ophthalmic practice are stored on magnetic disks. Data storage has been semiautomated by means of a microprocessor-controlled recording device for standard perimeters. Existing visual field records may also be digitized by means of a magnetic graphics tablet. Records are retrievable in real time and are graphically displayed at video terminals.
Diagnosis, Computer-Assisted↗
Laryngeal vibration patterns. Machine-aided measurements from high-speed film.
A report is given on the development of procedures to process laryngeal high-speed films to extract the glottal wave-form and other glottal measurements. The glottal waveforms that are derived by this direct method are being used to determine whether the pathological larynx is manifested in its abnormal vibratory pattern. The glottal waveforms measured by sonic-sensing pen tracing, cursor outlining, a photocell technique, and television camera scanning are presented and compared with the conventional polar planimeter method. To date, the television camera method is the most rapid procedure and can process approximately 400 frames per hour in a semiautomatic mode. This method determines the glottal area, length, and width by a combination of analog-digital circuitry and minicomputer processing. This information is being used to explicate the exact nature of the vibrational patterns produced by the normal and pathological larynges.
Computers↗
Local tumor hyperthermia using a computer-controlled microwave system.
A minicomputer-based system was designed to control the microwave (2.45-GHz) power to four local hyperthermia applicators. Errors in temperature measurement, due to electromagnetic field interactions with small thermocouple probes, are minimized by sampling the temperature only when the microwave power is off. The programmable controller can regulate the temperature in tumors in 0.1 degree C increments from 30 to 60 degrees C. This technique reduces temperature differences throughout the tumor at steady state to less than 0.4 degrees C and prevents skin burns.
Animals↗
Thick-section histometry of porous hydroxyapatite implants using backscattered electron imaging.
A histometry system has been developed to measure bone ingrowth into porous hydroxyapatite implants utilizing the backscattered electron image of thick sections. The system consists of a scanning electron microscope (SEM) with backscattered electron detector, digital beam controller, minicomputer based image digitization, and microcomputer based image processing, point counting, and lineal analysis. The SEM backscattered electron imaging mode yields high tissue contrast and sharp tissue boundaries, substantially reducing the lost cap and projection effect errors of thick sections. High-resolution digitization of the image substantially reduces the standard error of the estimates. By using the digitized image the tedious process of filtering artifacts and recording actual point counts, intersections, and intercept lengths is delegated to computer software. Performance of this system in a recent study demonstrated substantial ease of operator use and speed of measurement. In the absence of a digital beam controller an inexpensive video digitizer circuit board may be used to digitize photographic prints of the SEM images. The combination of increased accuracy, precision, operator ease, and speed suggests that this system can be useful for soft tissue-bone-implant histometry.
Animals↗
Digital computer analysis of M-scan echocardiograms.
In the past few years, echocardiography has emerged as a useful noninvasive clinical tool in cardiac diagnosis. Conventional methods for analyzing echocardiographic data involve time consuming and tedious manual techniques for measuring various distances and computing cardiac parameters of interest. This paper describes a useful method for automating the analysis of M scan echocardiograms both for routine clinical work as well as for special research oriented ultrasonic cardiac studies. Using a GRAF/PEN digitizer interfaced to a PDP-11 minicomputer system, relevant points of the ventricular and mitral valve interfaces, R-R intervals, and time and distance calibration points are entered from hard copies of M scan echocardiograms. The computer then determines all the parameters of interest such as left ventricular (LV) diameters, LV volumes, LV mass, ejection fraction, stroke volume, cardiac output, septal and posterior wall dynamics, as well as such mitral valve (MV) parameters as opening/closing velocities, excursions, and areas subtended by both MV leaflets. The data and results are stored on disc or tape and a report of the results is immediately available from a printer for incorporation into the patient's record file.
Diagnosis, Computer-Assisted↗
ESTRIP, a BASIC computer program for obtaining initial polyexponential parameter estimates.
A new BASIC exponential stripping program, ESTRIP, allows the relatively rapid calculation of initial polyexponential parameter estimates, as does the previously published FORTRAN IV program, CSTRIP. The potential advantages of the new program are that it can be run on microcomputers and minicomputers with BASIC capability and a relatively small core and that it can be easily modified by the user.
Computers↗
PC-based system for retrospective cardiac and respiratory gating of NMR data.
A method and a means for retrospectively clustering NMR k-space measurement profiles with respect to both cardiac and respiratory phases were developed to explore strategies for (1) reducing cardiovascular and respiratory flow/motion image artifacts and (2) improving T1 and T2 characterization of the heart. The image data are collected at a uniform rate so that echo (TE) and repetition (TR) times are independent of the varying cardiac cycle R-R interval and/or respiratory motions. Cardiac (C) time, respiratory (R) time or diaphragm position, and NMR data acquisition (A) cycle time are collected by microcomputer in parallel with free running (untriggered) image collection on a standard magnetic resonance imager. After the raw data equivalent of multiple images are collected, the C-A-R phase timing data are uploaded from the microcomputer to the scanner's minicomputer for use in a normalized C-R phase plane clustering of the image raw data. Each profile's position in the C-R phase plane is determined and then clustered into a new set of data, one image being equivalent for each desired C-R phase combination. These raw data are then zero-filled and (optionally) filtered to compensate for the nonuniform k-space sampling and, finally, reconstructed. Cardiac "cines" made from these retrospectively gated images are comparable to similarly phased triggered images. When high time resolution is required, retrospective gating can be expected to show improvements over triggering, especially toward the critical latter part of the cardiac cycle, where coronary artery filling occurs. The system described can readily be assembled from generally available components.
Electrocardiography↗
Sperm cell motility as a new experimental model for toxicological studies.
The effects of environmental and toxicological factors were tested in a new and "simple" biological system; the collective motility exhibited by ram spermatozoa. Motility of highly concentrated semen (greater than 1 X 10(9) cells/ml) was evaluated objectively with a multichannel reflectospermiograph (RSG) connected to a minicomputer for an on-line analysis. The effect was tested on one of the energy-producing systems in the sperm cells, while the other was inhibited by 2-deoxy-D-glucose or antimycin-A so that the energy source for motility was known. The effects of the addition of ethanol to the semen in various concentrations, as well as various levels of oxygen in the environment were tested. When motility of the sperm cells was driven by mitochondrial respiration, the intensity and duration of motility was inhibited significantly above a threshold level. At the same level of ethanol, the motility was not significantly affected when the energy source was the fructolysis pathway. The effects of oxygen level were tested below and above the normal oxygen level (21% O2). When fructolysis was inhibited, the motility was fully dependent on oxygen supply, namely, that lower levels of oxygen inhibited motility. It was also found that under higher levels of O2 (hyperbaric hyperoxia conditions) the motility was inhibited due to the known oxygen toxicity effects.
Animals↗
Quantitative analysis in single photon emission tomography (SPET).
Quantitative analysis can improve the sensitivity and specificity of single photon emission tomography (SPET) procedures, as well as reduce inter- and intraobserver variabilities. Quantification of the radioactivity distribution is the ultimate goal of SPET. In this review we consider the basic requirements for an optimum three-dimensional reconstruction of the radionuclide distribution to enable quantification. Attenuation and scatter correction as well as varying resolution are the major problems. In the older SPET systems quantification was hampered by the lack of system sensitivity and sufficient computer power. Therefore, the imaging system was often assumed to be shift invariant and linear and the attenuation throughout the object uniform. More sophisticated solutions have been proposed and with more or less success implemented, but not for application in daily practice. Knowledge (measurement) of the attenuation is often required. New generation SPET systems employing multi-detectors and super minicomputers will ease the implementation of these solutions.
Humans↗
Early lesions of mouse vibrissal follicles:: their influence on dendrite orientation in the cortical barrelfield.
There is a statistically significant order in the tangential orientation of stellate cell dendrites, both spiny and smooth, in layer IV of the barrelfield of the mouse parietal cortex. Neurones situated in a barrel side have most of their dendrites oriented towards the barrel hollow; those situated in the hollow preferentially orient their dendrites parallel to the long axis of the barrel. A quantitative measure of the orientation of individual dendrites in barrelfields of 60-day old mice was obtained using a semi-automatic computer-microscope and a minicomputer. In the same manner, the dendrite orientation of layer IV stellate cells was determined in barrelfields, whose (cytoarchitectonic) pattern had been experimentally altered through lesions of the middle row of the mystacial vibrissal follicles at birth. The dendrites of these cells are oriented in harmony with the novel parcellation of the cortex. Consequently, for cells in the altered areas of the barrelfields, the dendrite orientation is different from that of cells with identical positions in a normal field (see Fig. 8). We tentatively interpret these findings as an adaptation of dendrite orientation to an altered pattern of thalamic input to layer IV that, in turn, is a consequence of the peripheral manipulation.
Animals↗
Proliferative activity and characteristics of immunocytochemically identified oligodendrocytes in embryonic mouse brain cell cultures.
Dissociated brain cell cultures of 14-day-old mouse embryos (E 14) were used for studying, during development, the proliferative activity of oligodendrocytes which express myelin basic protein (MBP) and galactocerebroside (GC). This was done using a combination of 3H-Thymidine autoradiography and immunoperoxidase or immunofluorescence. Quantitative estimates of labeled cells were made using a Leitz Texture Analysis System (T.A.S.) coupled to a P.D.P. 11-34 minicomputer. Results showed that differentiated oligodendrocytes, which express both MBP and GC, are able to proliferate. According to the intensity of the immunostaining, strong MBP positive and weak MBP positive oligodendrocytes were observed. Only the weak MBP positive cells incorporated 3H-Thymidine. The highest percentage (22.5%) of 3H-Thymidine labeled oligodendrocytes was observed at day 6 in vitro, and was reduced by half at day 9 to 13. Oligodendrocytes which have undergone a first division are still able to proliferate.
Animals↗
Single photon tomographic imaging of a standard heart phantom with 201T1: a gamma camera based system.
A standard heart phantom (University of Iowa design), including discrete myocardial walls, a central blood pool, and a 24-cc transmural "cold" defect, was studied with both planar and transverse tomographic imaging. The heart phantom was filled with 201T1 and placed within a cylindrical tank containing water and 201T1 to simulate nonmyocardial background activity from the thorax. The tomographic imaging system used was a commercially available, rotating, large field-of-view gamma camera. Image reconstruction from 64 sampling angles was performed in a nuclear medicine minicomputer system. The percentage activity in the region of the defect (actual activity of 0) contrasted to the normal wall was compared between planar and 1.25-cm transaxial tomographic slices. Defect activity fell to between 65% and 85% of that of the opposing normal wall in planar images, whereas it fell to between 26% and 49% of that of the normal wall in the tomographic images. In most cases, tomographic defect activity was half or less than that in the planar image. The geographic extent of the defect was seen in an appropriate number of tomographic slices; i.e., the geographic 3.2-cm defect length was predominantly seen in three 1.25-cm transverse slices. We conclude that camera-based tomographic systems show promise for improved 201T1 myocardial defect detection and quantitation over conventional planar images.
Heart↗
Whole body distribution of 99mTc labelled autologous human granulocytes and radiation dose to cells and organs.
The whole body distribution of radioactivity as a function of time after infusion of 99mTc labelled autologous granulocytes was measured in three volunteers by means of a scanning bed, a scintillation camera and a minicomputer. Labelling was performed with a bisalt method without pretinning. There was a considerable initial lung sequestration (22%-31%) of the injected activity, which disappeared with an effective half life of 42 min. One h after infusion the activity was found mainly in the liver (41%), spleen (8%), lungs (9%) and kidneys (5%). Urine excretion amounted to 30% during the first 32 h after infusion. An injected activity of 100 MBq caused a radiation dose of 4.4 m Gy to the liver, 6.3 m Gy to the spleen, 3.7 m Gy to the kidneys, and 0.2 m Gy and 0.1 m Gy to the ovaries and testes respectively. The labelling procedure and the subsequent decay within the granulocytes gave them an absorbed radiation dose of 1.8 Gy after 25 min (i.e., at completion of the infusion) and 8.4 Gy after 4 h (i.e., the normal imaging time). In vitro tests revealed no signs of radiation damage to the cells.
Adult↗
A quantitative study of physiological cerebral atrophy with aging. A statistical analysis of the normal range.
A new method of discriminating pathological cerebral atrophy from physiological atrophy during aging is reported. The authors advocate a pixel counting method using a minicomputer for the quantitative measurement of cerebral atrophy. Five hundred cases were studied with this quantitative method and the normal range of the physiological atrophy was determined statistically. In order to estimate the degree of cerebral atrophy easily, the conventional linear measurement methods were compared with the pixel counting method using multivariant analysis, and a simple formula for the calculation of the degree of cerebral atrophy is proposed. Using this formula and the normal range, pathological cerebral atrophy is easily detectable.
Adolescent↗
Three-dimensional visualization of human Langerhans' cells using confocal scanning laser microscopy.
Most techniques used to visualize cells in tissues are accompanied by some distortion of the tissue due to fixation and sectioning. We here present a technique involving "optical sectioning" and three-dimensional reconstruction of fluorescence-labelled Langerhans' cells in human skin that avoids such problems. The instrument used to study the specimens was a PHOIBOS Confocal Scanning Laser Microscope (CSLM) built around a Zeiss Universal microscope. A software package for three-dimensional reconstructions of confocal sections was employed for calculations in a Hewlett-Packard HP9000-350 minicomputer running UNIX. Normal human skin obtained at plastic surgery or skin biopsy specimens from allergic, irritant, or control patch test reactions was studied. Epidermis separated from dermis by incubation in thermolysin or thick (25 microns) cryostat sections were incubated with fluorescein-isothiocyanate labelled mouse monoclonal antibodies directed against HLA-DR. To reduce the fading of immunofluorescence during microscopy, the specimens were mounted with glycerol in PBS containing p-phenylenediamine. The results indicate that CSLM is a powerful tool for investigations on Langerhans' cells in different conditions of the skin allowing a three-dimensional view of cells in unfixed or acetone-fixed preparations at the light microscope level.
Fluorescent Antibody Technique↗