January 9, 2009

New x-ray tech uncovers clues on mummy’s fractures

For Meresamun, a female Egyptian mummy and one of the Oriental Institute’s main attractions, the afterlife proved to be much harsher than her time growing up as a member of her country’s elite. A high-ranking and wealthy priestess in the temple of Amun, king of the ancient Egyptian gods, Meresamun suffered several fractured bones after her death, according to discoveries made by U of C radiologist Michael Vannier using new x-ray technology.

The fact that these bones were broken post mortem was unknown until this past September, when Vannier called the Oriental Institute about the hospital’s new CT scanner. CT, or Computed Tomography, scanners are machines that take a series of x-rays of a patient and use them to reconstruct 3-D images of that person. Although CT scanners have been around since the mid-1970s, the technology that comprises them is constantly improving.

“It’s like the computer graphics in the Playstation 3 or Nintendo Wii,” Vannier said of the advances in medical computers. “These games have abilities even advanced computers couldn’t dream of 15 years ago.”

So when the hospital became one of the first to receive a new 256-slice CT scanner, Vannier proposed rescanning Meresamun, whose body he had x-rayed only a couple months before, using the hospital’s then most cutting-edge 64-slice scanner. The new scanner is four times as powerful, producing better-quality images and reducing the amount of time the patient is exposed to radiation by hours, making it safer as well as more convenient.

Vannier said that the technology is so advanced that long-term patients have taken notice of the brevity of their scans. “When the technician comes in after they’re done, they think something is broken,” he said. “They’re used to having to stay there much longer.”

For Meresamun, and the scientists who study her, improvements in x-ray machines like CT scanners are especially important. At the time of her death, it was the fashion in Egypt to wrap mummies using cartenage, a material similar to paper-mache. Unfortunately for those studying mummies, and in particular Meresamun, cartenage attaches itself securely to the body of the deceased.

“Unwrapping Meresamun would mean destroying her,” said Emily Teeter, an Egyptologist at the Oriental Institute, who arranged for the new x-rays. “They’re absolutely revolutionizing how we are studying mummies.”

Scans of Meresamun in the early 1990s revealed her fractured jaw, sternum, and arm, but scientists at the Institute were unable to figure out when these injuries occurred. With the 256-slice scanner they were almost immediately able to determine that they occurred after Meresamun’s death.

Vannier, a “closet Egyptologist himself,” according to Teeter, is just as excited about the historical application of the scanner.

“There’s good reason to think about rescanning many mummies,” he said.