Michihiro Sasagaki

Cerebral and Cerebellar Activation in Power and Precision Grip Movements: An H215O Positron Emission Tomography Study

Most human manual grip movements can be divided into power gripping and precision gripping, but central neural control during these tasks remains unclear. We investigated activation of the whole brain to analyze how simple hand movements are performed. The cerebral blood flow of seven healthy right-handed volunteers was measured by H215O positron emission tomography during right grip tasks without gripping a target object. Auditory-cued, repetitive power grips (i.e., fist making) and repetitive precision grips (i.e., opposition of the tip of the index finger and the tip of the thumb) were performed at 1.26 Hz. The areas activated during both tasks were the left primary sensorimotor cortex, caudal portion of the dorsal premotor, caudal portion of the supplementary motor area, cingulate motor area, and the right spinocerebellum and intermediate region of the cerebrocerebellum in comparison with the rest state. The analysis of power grip-precision grip tasks showed the activated peaks in the upper portion of the left sensorimotor area and right cerebellar vermis, but these areas were activated in both the tasks [(power grip-rest) and (precision grip-rest)] with uncorrected P < 0.001 as the statistical criterion. With P < 0.05 corrected as the statistical criterion, the results showed no significant activated peaks in regional cerebral blood flow. Our findings indicate no difference in brain activation between the acts of power grip and precision grip without a target object.

Development and evaluation of PC-based HIS-RIS-modality-PACS coupling: the results of evaluation of initial stage with personal computer application

A PC-based HIS/RIS/Modality/PACS coupling was developed and operated where hospital-wide PACS was closely cooperated with the HIS and RIS. Three workstations with a magneto-optical disk (MOD) juke-box for each one were used as PACS servers to collect images from eight computed radiography systems and three CT scanners. An implementation of JPEG compression reduced network load and storage volume. Twenty PACS-terminals can be connected to the PACS servers and get images from them. Functions of the terminals are magnification, tone scale modification and mensuration. The physicians can also get images on HIS-terminals employing improved HIS-terminal functions. This system has many advantages: (1) inexpensive; (2) close cooperation with the HIS and RIS which makes them easy to manage and retrieve images automatically; and (3) it is an open system, which enables us to apply new technologies. As a matter of fact the introduction of a new PC and a new OS made it possible to decrease displaying response time.

PACS in Japan and progress of technology assessment

The statistics of PACS installations in Japan and the progress of key technologies over the past 13 years (1985-98) are described. The total number of installations of more than 557 is comparable with that (517) of hospital information systems (HIS), because advanced electronic technologies have brought a rapid spread of PACS for these 13 years. Examples of large sized PACS in Japan are discussed and a method for integrating HIS and RIS (Radiological Information System) is described. Standardization activities on PACS in Japan such as image data transfer and filing are also introduced. A unique domestic standard in Japan for IS&C (Image Save and Carry) and electronic filing of medical images is presented. The realization of DICOM in Japan is also described. Technology assessment of PACS is discussed in terms of methods and the results of measurement. Examples in the Osaka University Hospital over 6 years (1992-98) are presented. In order to figure out the effectiveness of PACS itself, the HIS/RIS contribution to radiological examination and reporting was measured before PACS was implemented. The total aim of the whole system operation is to maximize the effectiveness of HIS/RIS/PACS integrated each other. The results of time study, character counting in radiological reports, network loading study and other measurements are employed to expand the size of PACS in Osaka University which has 20 terminals at present.

Generalization of methodology of measurement for clinical evaluation of HIS/RIS

To establish generalized method of quantitative measurement of clinical effectiveness of HIS/RIS, a method of comparison between pre/post operation of a system and between different systems operated in different hospitals was proposed. A generalized method for calculation of effectiveness index by score functions was developed. The results of measurement and calculation were applied to look for the timing of version up of the systems and also will be applied to grasp the effectiveness of revised systems. We have measured clinical effectiveness quantitatively along the method of technology assessment of HIS/RIS in Osaka University since 1993. Objects of measurement in HIS were time study such as consulting time, machine operation time, machine operation time with conversation between a physician and his patient and so on. And objects of measurement in RIS were reporting time for image diagnosis, writing time for a report and number of characters written in a radiological report and so on. Actual numerical value of index was calculated according to the developed score function and variables measured in 1998 and 1999 for HIS, and also according to the score function and variables measured in 1993 before RIS operation and after RIS operation in 1994, 1995, 1996, 1998 and 1999. The measurement and calculation will be carried out in other hospitals at large and the indices will be compared between hospitals in terms of system characteristics.