Seeing Inside with CT Scans

The CT Scanning Project

The Field Museum possesses a considerable collection of mummies, most of which date to the 1893 World’s Columbian Exposition held in Chicago. Many have not been on display since, and most have also never been studied thoroughly, due to the risk of irreversible destruction involved in unwrapping such fragile specimens.

However, in 2011, a mobile CT scanner generously provided by Genesis Medical Imaging changed everything. The Museum’s mummies were scanned on site and “unwrapped” virtually in software, thereby avoiding a risky ride to a hospital.

Over six days in July, Museum scientists performed non-invasive CT scans of human and animal mummies from Egypt and South America. The secrets hidden inside—such as the grave goods buried with individuals, the processes used to mummify them, and even their age, sex, injuries, and physical defects—could be seen in remarkable detail, without damage to the specimens.

By studying the modern scans of these mummies, scientists have uncovered a wealth of new information about life, death, and the quest for immortality in Egyptian and South American cultures.

Mummifying Animals

Archeologists often find mummified animals in the tombs of Egyptians. In some cases, these appear to be household pets, perhaps intended to provide companionship in the afterlife.

Occasionally, mummified animals appear to have been meant as a source of food for the deceased, to sustain him or her during the journey to the other world.

However, most animal mummies were offerings to a god associated with the animal. Archaeologists have uncovered enormous cemeteries all over Egypt containing thousands of mummified cats, birds, crocodiles, and more.

Inca Mummies

Perhaps the most well-known South American mummies are the Inca ice mummies, called the capacocha, or “royal blessing.”

As the honored children of local nobles, they traveled from their homelands to Cuzco, the Inca capital, where they were celebrated and received gifts.

After they returned home to their native province, priests fed them corn beer and quickly sacrificed them to send them to the gods. Their bodies, along with gifts of gold and silver figurines and fine pottery, were then buried on icy peaks as messengers to the mountain deities.

CT Scanning

Due to their extreme fragility, the last time many of the Museum’s mummies were examined was in 1931, when conventional 2D x-rays of them were published in Fieldiana. These x-rays often raised more questions than they answered.

Thanks to the generosity of Robert Dakessian, President and CEO of Genesis Medical Imaging, a mobile medical CT scanner mounted in a specially adapted truck was brought to the Museum, where it was set up in the West Parking Lot and used to generate scans of specimens.

Scanning Specialists

The Museum invited many specialists—such at Dr. Michael Li, DDS, MS from UIC Orthodontics, Dr. Jeffrey Rosengarten, MD, Chairman of the Department of Radiology at Northwestern Lake Forest Hospital, and Dr. Mary Peters, DDS and volunteer in the Museum’s Geology Department—to view and analyze the scans.

These specialists helped to clarify the sex, age, and health issues faced by each specimen, and determine whether injuries to the mummies were sustained before death, during the embalming process, or some time afterwards.