Before treating a tumor with radiation, an oncologist must decide how to direct the radiation beams so as to minimize damage to surrounding tissues without compromising efficacy. That kind of planning may soon become more accurate, thanks to true 3-D displays whose software Joshua Napoli helped pioneer.
The image on the left shows different perspectives on the same plan for treating a brain tumor with radiation: red marks the tumor site, blue marks critical structures such as the brain stem (which must receive as little radiation as possible), and green marks the proposed path of radiation beams. The images, 25 centimeters in diameter, are projected inside a somewhat larger dome; this “volumetric display” is made by Actuality Systems of Bedford, MA, where Napoli is head of software development.
Napoli’s software breaks up 3-D models generated by a computer into hundreds of frames that are projected onto spinning panels inside the dome, making a smooth, interactive image. The software has produced the highest-resolution volumetric 3-D displays in the world, Napoli says. Along with doctors at three hospitals, Actuality is studying whether radiation plans made using its displays are superior to those made using traditional monitors. Eventually, doctors could use the 3-D displays to view most types of medical scans.
Already, petroleum companies are using them to help visualize oil and gas deposits, and pharmaceutical researchers are using them to help picture how potential drugs interact with their targets. One of the biggest challenges, Napoli says, has been engineering the underlying graphics-processing software to work with real 3-D displays; displaying 3-D images this way requires a computer to process about 50 times as many picture elements as it would if the images were displayed on flat screens.