This study describes a remote surgical guidance and navigation system developed for surgery using “Open-MRI” and
high-speed network. We connected Osaka University Hospital and Kawasaki Hospital which has deployed Open-
MRI with high speed IP over ATM network. The distance between two hospitals is approximately 50 km. Two
video cameras were installed with an angle of 40 degrees on an open-MRI gantry to obtain intraoperative images.
Two pairs of CODEC (AD/DA converter) were equipped on the network to transfer both images and sound in real
time. A pointer system to indicate a region on an image was also developed. MRI images obtained by Open-MRI
were transferred to a 3D workstation in Osaka University Hospital. The system was designed for a senior surgeon in
Osaka University to advise regarding accurate needle direction for a remote patient by checking the reconstructed 3D
images and schemata shown by the navigation software. The schemata were also superimposed on intraoperative
images from two cameras, and the superimposed images were sent back to Kawasaki Hospital. This system allowed
a surgeon in the operation room at Kawasaki Hospital to accurately view navigation schema under supervision by a
senior surgeon in a remote university hospital with superimposion of intraoperative images. The pointer system
allowed both doctors to share intraoperative images during a virtual-real surgical operation. A successful biopsy
case using this newly developed system illustrates the effectiveness of this system.
Proc. SPIE. 3980, Medical Imaging 2000: PACS Design and Evaluation: Engineering and Clinical Issues
KEYWORDS: Surgery, Medical imaging, Image quality, Time metrology, Software development, Radiology, Technetium, Internal medicine, Time multiplexed optical shutter, Picture Archiving and Communication System
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.
For efficient storing of medical motion images such as digital cine angiography, optimized compression ratio for motion image and efficient mass storage media is required. We have many selections to compressing motion image. MPEG-2 is one of de facto standard in motion image compression techniques. In order to find out optimized compression ratio using MPEG-2, both subjective evaluation and objective evaluation were carried out. These evaluation methods are based on severity decision of vessel stenosis for coronary vessel. From these results, we found optimized compression ratio using MPEG-2 is 1:80. In case of employing DVD-RAM media as storage media of medical motion images, the cost for storage is slightly more expensive than in case of employing CD-R media.