the grid size. This was considered to be sufficient for the purposes of this study.

Future Directions

This application has potential for far greater automation and data storage, perhaps using ArcView itself. Adopting the ArcView approach would facilitate the data entry process in that the physician could geocode the data, not onto a hard-copy sketch with subsequent transfer, but with a single click of the mouse on the appropriate image. The other data-entry components could also be more user friendly than they currently are.

Further research into the spatial distribution of melanoma in the study group is also possible. Examination of the channels taken through the lymphatic system may reveal some correlation between it and one or more of the independent variables recorded.

Integration of the images obtained from the digital gamma camera with the application is also a long-term goal. If some reasonable common reference points could be introduced to the lymphoscintigraphic images, a registration and rectification process could produce a normalized representation with far more detail than is currently stored in the system. Techniques such as neural-net pattern recognition could also be used to classify channels and nodes.

For more information, contact Andrew Coates BE, School of Civil Engineering, University of New South Wales, Sydney, Australia.; Dr. Roger F. Uren FRACP DDU, Nuclear Medicine and Diagnostic Ultrasound, Missenden Medical Centre.