Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering
Transport Technology

M.B. de Kleine Technische assistentie voor optimalisatie telprocedure bij operaties
Literature survey, Report 2005.TL.7016, Transport Engineering and Logistics.

During medical surgery several sponges are being used. Before closure of the wound all sponges must have been removed. Not removing all the sponges can result in physical complaints and possibly a decline in the patient's health. To ensure that no sponges have been left behind, a counting procedure is being used during surgery. If there is any doubt about the presence of sponges in the patient's body, an X-ray photo is taken.

Possibly, the chance of a sponge being left behind in the patient's body can be reduced using modern day technology. Using two main questions, an analysis of the possibilities has been made. The first main question is whether the counting procedure can be improved using modern day technology. The second main question is which possibilities, besides X-ray, are available to detect sponges in the human body.

Both main questions are based on the same question; how can an object be detected? The principles of detecting have been analysed and categories have been formulated. Highly used detection methods (e.g. Radio Frequency Identification (RFID) and MRI) have been examined. A number of patents have also been examined.

During this research it appeared that for many years people have tried to reduce the probability of a sponge being left behind. Many patents have been claimed, but none of the patents has led to a reliable and beneficial solution. The current counting procedure has a high reliability. A technical assisting system has to be very reliable in order to be able to assist during the counting procedure.

The detection methods that have been analysed showed a limited level of reliability. Costs are also an issue. Because the current counting procedure is functioning at a high level, a new system has to be affordable besides being very reliable.

Of all detection methods that have been discussed, RFID is most suitable for assisting in the counting procedure. Other methods mainly focus at sponge detection in the human body. Still, the scan range and reliability of RFID are not adequate enough for the system to be of any support during the counting procedure. Also, RFID is still too costly. The costs of the tags will decrease over time, especially when large amount of tags are being produced.

It can be concluded that RFID can not be of any support during the counting procedure, but may become so in the near future if the scan range and reliability increase while the costs decrease. Because the current counting procedure is functioning at a high level, it is hard to make an improvement in this counting procedure. More interesting is how the detection of sponges in the human body can be improved. This can be done by increasing the radiopacity of the sponges when using X-ray. Further research on how the radiopacity can be increased is needed.

Reports on Transport Engineering and Logistics (in Dutch)
Modified: 2006.02.05; , TU Delft / 3mE / TT / LT.