December 2005

CT Scan to Go

First portable CT scanner for heads could fit in an emergency room.

By Tom Mashberg

The tremendous imaging power of computed tomography (CT) has helped transform medicine. But to date, CT scans have been beyond the reach of battlefield medics, ambulance crews, and even many emergency-room doctors.

That's because conventional high-resolution CT scanners weigh almost 4,000 kilograms, require high-voltage power supplies for massive cooling systems, and must be installed in climate-controlled radiology suites.

The lack of quick access is a particular problem in cases of brain trauma or stroke, when speedy treatment is critical.

NeuroLogica, a startup in Danvers, MA, believes its small, rugged, and portable machine will make CT scans more accessible. "Our primary emphasis was on getting a CT machine in an ambulance and emergency-room setting for heads only," says Bernard Gordon, the company cofounder, who estimates that 15 to 20 percent of CT scans are for the head and neck. "We need a machine they can afford all over the world that is rugged and can be worked by people with far less training than most radiologists."

By 2005, a year and a half after NeuroLogica was founded, it had developed a machine suitable for emergency rooms and obtained U.S. Food and Drug Administration clearance for it; the company expects to deliver its first product this winter. It is now working on a version that could fit in ambulances.

The traditional CT scanner is a behemoth that looks like a giant point-and-shoot camera, with a hole in the middle instead of a lens. As a patient is conveyed through the hole, the machine continually shoots x-rays, and software combines the resulting images.

After Gordon and two cofounders started NeuroLogica in 2004, they set out to shrink the power supply and cooling system so they could use smaller x-ray-emitting tubes.

In whole-body CT scanners, these tubes can be 30 centimeters in diameter and 50 centimeters long. NeuroLogica's engineers used tubes about 10 centimeters in diameter and 15 centimeters long. They created a power system about the size of a microwave oven, with a small fan to cool the tubes.

The combined miniaturizations let them reduce the diameter of the donut-shaped machine to 44 centimeters, while the "donut hole" stayed at 32 centimeters, large enough for a human head. The machine delivers the same resolution as large machines, but the scanning speed is slower: a head scan can take up to two minutes, considerably longer than with a traditional machine.