Diverse developments enhance image-guided therapy

In addition to image-guided therapy developments, further refinements keep changing the field.

Researchers at the National Institutes of Health recently developed an electromagnetic positioning and navigation system to guide interventional procedures. The "mini-global positioning system" consists of a small electromagnetic field generator that beams and tracks signals from tiny sensors on the tip of a biopsy needle or ablation probe. Signals then go to a computer that provides real-time location of the probes in correlation with preprocedural imaging.

The technology stitches together CT, MR, and PET imaging data sets with electromagnetic mapping of the area of intervention. The mini-GPS provides accurate navigation coordinates at the time of needle placement and again if the needles should need to be repositioned during the procedure.

The system pinpoints tumors that are hard to see with conventional imaging or that disappear from ultrasound screens when they are being cooked. The NIH researchers presented the technology at the 2004 RSNA meeting.