[en] The four applications of functional mapping, which are ongoing projects at the National Institutes of Health, demonstrate the clinical and research usefulness of this form of computerized image processing. Functional imaging not only yields an efficient reduction of large amounts of quantitative data, but also provides a visual presentation in which abnormalities can be easily appreciated. The examples presented illustrate several different approaches to the regional quantitative assessment of physiologic function, producing valuable clinical information in a manner which is not conveniently available by more conventional techniques

[en] NUMEDICS II utilizes a new design for large nuclear medicine computer facilities, a distributed resource computer network. Among the advantages of this new design are: data acquired at any designated site within the hospital may be processed and interpreted in central locations, hardware failure causes system degradation rather than a total loss of function and the overall configuration permits expansion as necessary and is adaptable to new imaging devices

[en] The gamma-cine-cardiographic data allow the construction of functional images showing the local variation of some dynamic parameter. The very simple technique for the storage of the data described is inexpensive and useful in any case of data storage system and its two principal disadvantages (no normalisation of the cardiac cycle duration; low digital resolution of the images) are not very important for this particular application, respectively for the following reasons: the dynamic parameter which is displayed is calculated by taking in account only the systolic part of the cardiac cycle; the statistical accuracy of the dynamic curve calculated for one single point is better if this point corresponds to a larger area of the camera field and a compromise must be found between resolution and counting accuracy

[en] The alternative method of visualisation provided by longitudinal tomography, where sections parallel to the long axis of the body are produced, may, in practice be more appropriate for long or flat organs such as the lungs, skeleton, thyroid, spleen, kidneys etc. The images produced correspond more to the projections usually obtained in radiography or nuclear medicine and may therefore be more recognisable. Often the organ as a whole may be imaged in this way rather than as a series of transverse sections. Instrumentation used for longitudinal tomography includes the tomographic scanning camera type of device developed by Anger which provides details of a number of planes simultaneously and the conventional scanner using a large solid-angle highly focussed collimator. This scans the patient with one plane at the focus of the collimator after which the detector is raised and the patient rescanned, the process being repeated for a number of planes at the focus of the collimator. These types of instrument suffer from the disadvantage that out-of-focus planes are superimposed on the in-focus image and therefore seriously degrade the available useful information. A scheme of correcting for out-of-focus images to yield enhanced images of individual longitudinal planes is outlined

[en] A general image handling software system has been developed for on-line collection, processing and display of gamma camera images (IMAGE system). The most distinguishable feature of the system is the ability for the user to interactively specify sequences, called macros, of basic functions to be performed. Information about a specified sequence is retained in the system, thus enabling new sequences or macros to be defined using already specified sequences. Facilities for parameter setting and parameter transfer between functions, as well as facilities for repetition of a function, are included. Finally, functions, be it basic or macro, can be specified to be iteratively activated using a physiological trigger signal as f.ex. the ECG. In addition, a special program system was developed for handling the dynamic data, from Xenon-133 studies of regional cerebral blood flow (CBF system). Parametric or functional images derived from the CBF system and depicting estimates of regional cerebral blood flow, relative weights of grey matter or other parameters can after computation be handled in the IMAGE system

[en] The system presented is the Searle Nuclear-Chicago Data Processor for Nuclear Medicine, the Clincom. The system has been designed to fulfil the data processing needs in the daily routine in a nuclear medicine department, where computer-skilled personnel is normally not available. Therefore one of the outstanding requirements in the design has been the ease of operation. A clinical program has been developed that enables a large number of routines to be performed by pressing just a pushbutton on the front panel. A further design criterium has been that the Clincom could be placed at a reasonable distance of the camera for example in another room, in order to optimise both patient's and operator's convenience

[en] Using the scintillation camera and small computer a technique has been devised to correct the count rate curve over the transplant kidney for background radioactivity following IV injection of I-131 hippurate. The background correction using I-131 hippurate alone has been validated against a more precise background correction using I-131 albumin. Using kidney and bladder curves properly corrected for background radioactivity, reliable estimates of renal uptake and excretion of I-131 hippurate may be obtained using a renal transplant evaluation computer program

[en] This paper has tried to show how an internal noise source (darklight and threshold jitter) would tend to explain experimental data concerning the visual detection of noise-limited signal. The interesting conclusions can be drawn that the internal noise sets the upper limit to the utility of data processing techniques designed to reduce image noise. Moreover, there should be instances where contrast enhancement techniques may be far more useful to the human observer than corresponding reductions in noise amplitude, especially at high count rates. Then too, the limitations imposed on the human observer by an internal noise source, may point towards the need for additional methods (e.g. computer/microdensitometer) of interpretating images of high photon density so that the highest possible signal to noise ratio might be obtained

[en] The technique described should be considered as a first step towards the classification of scintigraphic data where the energy is included. As in all such studies the interpretation of the resulting images is not necessarily at first evident, and certain experience needs to be established. This applies in particular to the images obtained with the higher factors. It is possible that the use of this technique may resolve, without requiring a priori information, the problem previously encountered using the other 'subtraction' type techniques

[en] One important facility which gives great flexibility to any system of acquisition of dynamic study data, is a listing of the numerical data that makes up each activity/time curve, preferably in a computer compatible form such as paper or magnetic tape. One further requirement is to encode at least an identification number representing the patient studied. In addition it is useful to encode the sampling time and signals identifying the beginning of data, end of data, the activity/time curve and specifying the equipment producing the data