Issue 6.11 | Nov 1998
Watermelons and eggplants are not your typical operating-room fare. But they worked for Patrick Sewell, an assistant professor of radiology at the University of Mississippi. Sewell is the first physician in the US to perform MRI-guided cryoablation, a new cancer therapy that combines a procedure for freezing tumors with magnetic resonance imaging.
Sewell conducted biopsies of "phantom tumors" (really vitamin E capsules) inserted into sundry edibles to familiarize himself with the devices that, when used together, make the technique possible: an MRI machine made by GE Medical Systems, and CryoHit, an MRI-compatible cryoablation unit from Galil Medical.
By relying on MRIs rather than ultrasound to monitor the extent of freezing and tissue damage, CryoHit offers better visibility during surgery. GE's imager, which is wide enough to walk into, increases access even further: It's "like being inside the patient's body while you're still in the control room," says Sewell. CryoHit works by sending pressurized argon through a thin probe, which depressurizes at the tip, sucking heat from surrounding tissue and creating an ice ball in the tumor. The freezing-and-thawing process ruptures cancer cells, which stop growing and are reabsorbed into the body.
It's hard not to blink at the price tags on GE's machine (US$2 million-plus, more than double that of a standard machine) and CryoHit (up to $200,000 per machine). Then again, annual cancer-related medical costs in the US already amount to $37 billion.
- Julie Greenberg