It started when I attended a Siggraph talk (August 1990) on path planning.
I always enjoyed attending Siggraph for two reasons. First, I had made a large number of technical friends and each year I added more to the number. Second, the technical talks were so stimulating and I always came away with some new ideas.ii I sat in a talk that solved robot path planning using a discrete spatial representation. I remember thinking that this technique might help be used to navigate virtual cameras through internal passages in CT data. I was doing work for GE Aircraft Engine at the time and I had tried unsuccessfully to navigate interactively through the internal serpentine passages in a jet engine turbine blade. I was able to quickly implement the technique and got some pretty impressive results. On a visit to Brigham and Womens Hospital, I showed the movie I made to Ferenc Jolez, Director of MRI. Ferenc suggested that we try to fly through colons, arteries and brains. Once again this simple idea produced really interesting results. Subsequent to this, I showed the animations to Rick Satava, a DARPA Program Manager. He urged us to submit a proposal to DARPA's technology reinvestment program (TRP). We won the two year contract and refined the techniques.
We coined the term Virtual Endoscope although we may not have been the first. Other sites, namely Wake Forest, Mayo and Duke created early virtual endoscopy systems.