Although various methods have been proposed for quantitative evaluation of gait, they are not yet widely used as routine clinical tools. The reasons are: 1) measuring systems are too expensive and complicated, and 2) the validity of the methods is not fully examined in a statistical manner.
In this paper, the validity of a new evaluation method based on a simple foot-force measuring device is investigated in terms of the correlation between quantitative indices and visually-rated grades.
Fourty-eight hemiplegic patients due to cerebral vascular accident were asked to walk on a 15m straight level floor. Four raters independently evaluated each subject in 8 gait characteristics or items in 1-4 grades on the basis of visual inspection. These items include asymmetry, variability, instability, and dependence on cane. At the same time, vertical ground-reaction-force exerted on the right and left foot and on the cane was measured, and then quantitative indices representing the above 8 items were derived.
All but one indices show reasonably good correlation with the mean grades of the 4 raters in corresponding items, thus demonstrating the feasibility of these indices. Statistical analysis also reveals several problems inherent in visual rating, such as inconsistency in the interpretation of evaluation criteria among raters, and degradation of independence of items due to rater's subjectivity.

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The automatic chromosome karyotyping based on the difference of staining methods has been discussed from the standpoints of specimen making, feature representation, processing procedure, recognition rate and statistical analysis. Experimental sytem was set up to certify the usefulness of the integrated intensity profile. And a new algorithm has been proposed to improve the recognition rate and a new output method has been proposed for karyotyping in order to simplify the system. Selection of the integrated intensity profile as a feature of G-staining specimen has been adopted to realize the simple and useful chromosome classifying system.

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Computed tomography (CT) provides information about patient contours and localization of both tumor and sensitive normal structures, and is expected to significantly improve the accuracy of calculated dose distributions in treatment planning. Therefore, most whole body CT scanner systems commonly include software for dose distribution calculation in treatment planning. But it is usually impossible to mark treatment parameters, such as the beam directions, corners of radiation fields and the center of tumor, on the skin surface of a patient.
We have developed a new optical positioning apparatus (OPA) and attached it to a commercial CT scanner (Pfizer/AS & E model 450). We have also developed an operation software for consistently carrying out treatment planning using CT images and for marking the determined treatment parameters on the patient skin surface. It was named the patient beam positioning system (BPS).
The OPA is an optical apparatus which can irradiate a laser spot beam for any direction on the patient's skin surface. Four parameters are needed to control the OPA. The source position of the light spot beam can be rotated around the central axis of the gantry on the transaxial plane (α rotation) and it can be translated in the direction of the central axis (z translation). The light spot beam can be aligned in any direction by two axis rotation of tilt angles on the transaxial plane (β rotation) and on the longitudinal plane (γ rotation). α of the rotation angle is within ±100° and z of the translation length is 0-300mm. β of the tilt angle on the transaxial plane is within ±120° and γ of the tilt angle on the longitudinal plane is within ±45°.
The OPA is connected with the computer system (DEC PDP LSI-11) of the CT. By observing CT images on the CRT screen of the CT console, target volume is defined, and field size and beam direction of each beam are decided enclosing the target volume by interactive operation. The operation software is in three parts. The first is the program to manipulate treatment parameters superimposed on a displayed CT image. The second is the program to calculate dose distributions using the determined parameters. For this purpose, we use Pfizer's CTRT program based on the TP-11 treatment planning system. The third is the program to control the OPA according to parameters determined in the former program.
In this report on the first version of the software, the center of tumor, and the central beam axes and the four corners of the rectangular fields are marked on the skin by the OPA. The spot size of laser beam is about 6mm and total accuracy of hardware for marking on the skin surface is within ±2mm. Clinical work using the BPS has been started.

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The auditory evoked slow vertex response (SVR), or so called auditory cortical response, has been used as a method of objective audiometry. The processing of SVR has been done mostly by conventional averaging so far, but there are some unsolved problems, such as the false positive response and the unreliability of response especially with infants under sleeping states. We have, under the circumstances, designed a series of computerized procedures using the PDP 11/60 computer in order to obtain reliable SVR.
Methods:
(1) Analysis of average power spectrum of EEG, with or without acoustic stimuli.
(2) A non-recursive digital bandpass filter using the fast Fourier transform has been designed in order to detect SVR.
(3) A recursive digital bandpass filter (Butterworth) using Z-transform has been designed in order to analyze the alpha-attenuation with acoustic stimuli.
Results:
(1) Averaged power spectrum had its peak at around 3 to 5Hz, when the acoustic stimuli were clearly perceived. On the other hand, it had its peak at around 9 to 11Hz, when the acoustic stimuli were not applied to the subjects.
(2) The most effective pass-band for detecting SVR using the non-recursive digital filter was 3 to 9Hz.
(3) The detectability of the digital filtered SVR in adults and infants was improved in comparison with the non-filtered SVR.
(4) In recursive digital filtering, the alpha-attenuation was observed more clearly with subjects given acoustic stimuli than with nonstimulated subjects.

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A new method has been devised to estimate the epicardial potential distribution from the measured body surface mapping. In this method, the heart shape was approximated by a half of spheroid and the spheroidal harmonics expansion of the cardiac field was used to relate the epicardial potential distribution and the body surface potential distribution.
To investigate the validity of this method, the animal experiment was conducted with an intact dog and its epicardial and body surface potentials were recorded simultaneously. The epicardial potential distribution calculated on the heart approximated by a spheroid from the measured body surface potentials was found to be in fairly good correspondence with the measured epicardial potential distribution during QRS complex.

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Tracking the motion of coronary arteries in cineangiograms is useful to describe the motion of heart wall and to examine the condition of coronary flow based on spatial and temporal distribution of the density of contrast material. Cineangiograms used for the motion analysis have poor contrast because the quantity of contrast material is forced to be limited in order to keep the heart beat as normal as possible. Moreover, examination of coronary flow necessitates analysis of the regression process of the contrast material.
This paper describes the digital processing methods for moving images to analyze the motion of arteries in such cineangiograms. Tracking methods are different for such distinct parts as branch points and curved corners and for nearly straight parts of arteries. This is because the former parts have low correlation with their neighbors, whereas the latter parts have high correlation.
The template matching method is used for the detection of corresponding distinct parts in adjacent frames. The prediction for the positions of corresponding points based on the results of tracking in previous frames is utilized for faster matching.
For tracking nearly straight parts, a circle is drawn with its center at a distinct point. Then a pair of peaks in differential distribution of the density along this arc are chosen as wall boundaries of an artery. Again, the prediction for the positions of wall boundaries based on the result of tracking in the previous frame is used for faster tracking.
The above methods are successful in tracking the motion of arteries with poor contrast cineangiograms and in drawing regression curves of contrast material at different parts on the arteries, from which the condition of blood flow can be examined.
This paper treats the motion of arteries in cineangiograms, that is, the motion in the two-dimensional projection plane. Three-dimensional motion can also be analyzed by applying above methods to biplane-type cineangiograms.

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