- New database offers more than 15,000 full-body CT scans for research
- Each scan contains 10,000+ images and privacy-protected metadata
- Database will further research in forensics, anthropology, and public health
People die. All the time. From many causes, including old age, disease, accidents, murder. But there’s a lot researchers can learn from these deaths.
Dr. Heather Edgar, forensic anthropologist at the University of New Mexico Office of the Medical Investigator (OMI) and associate professor of anthropology, has converted a dataset of whole body decedent CT scans into a searchable database.
The New Mexico Decedent Image Database (NMDID) website will offer qualified researchers free access to more than 15,000 full-body CT scans, along with corresponding information about the deceased.
Edgar’s idea to create a decedent image database was inspired by her own work in anthropology. “As an anthropologist, I’m very interested in human variation and I thought that this would be a fantastic resource for research,” she says.
“CARC staff helped to develop a safe, secure, long lasting storage solution,” Edgar said. “Also, they are helping to develop the method by which we will deliver the scans to the researchers.”
According to Edgar, there were numerous challenges to putting together this database.
“There are many moving parts to this project, from biomedical informatics, to website design, to safe storage, to scan delivery, data use agreements, and many other components. It’s my job as principal investigator to keep the machine running, and it’s very challenging to keep track of everything,” she noted.
The OMI is only one of two centralized, statewide offices for medico-legal investigation. About 35 percent of deaths in New Mexico are processed through the OMI. It is also the only medical examiner’s office in the US that routinely makes CT scans of nearly every individual whose death is investigated.
Between 2010 and 2017, the OMI created over 15,000 whole body CT scans, a research resource that is unmatched anywhere. Each scan contains 10,000-12,000 images. That many high-resolution scans for each body has generated massive amounts of data, requiring a large system that CARC offers to store it.
“We have to clean and standardize that data and match it with the scan. We are also calling next of kin to get more information about the decedents,” said Edgar. “All the metadata will be together in one database, and the CT scans will be matched by a new number to the set of metadata about them.”
Privacy and anonymity are preserved. Edgar’s team included CARC specialists that ensured scans and personal information will not be identifiable by name and that unauthorized users won’t be able to access the database.
“Remember that all the scans are de-identified, and no one’s scan will be traceable to the person when they were alive or to their family. Also, only qualified researchers can access the data, and they have to submit a research request to get access to the scans,” Edgar explained. “We’ve been really, really conscious of privacy protection. We’ve put in a lot of safeguards.”
The possibilities offered by the NMDID are endless. Research in pathology, radiology, anthropology, anatomy, oncology, public health, safety, forensics, dentistry, and many other areas of study could benefit from the NMDID website.
Edgar noted that “one project I can foresee is to develop statistical error rates for commonly used methods of individual identification. Sometimes normal methods of identification, such as fingerprints or dental records, are not available. In these cases it’s not unusual for someone to be identified radiologically, by comparing an ante-mortem (before death) X-ray or CT scan to a post-mortem one.
“Often people use the shapes of the frontal sinuses to do this, assuming that each frontal sinus is unique. If two sinus patterns match, the person is identified. But we really don’t know how unique the shapes of the frontal sinus are.
“Using this dataset and a machine learning approach, we can determine how commonly a misidentification might be expected to occur. This lack of an error estimate isn’t unique to frontal sinus identification. It’s true for fingerprint analysis too.
Edgar says that she can’t foresee all of the possible research uses of the database. “I can see how anthropologists would use it for forensic purposes, but also to study human variation in order to better draw inferences about human evolution. I can see tons of ways forensic pathologists and radiologists will use it. I can even see safety engineers and social scientists using it.
“But, I am sure there are research questions that can’t currently be addressed, that will be possible to investigate using these data, that I can’t even dream up,” she said.
The NMDID website is in final stages of testing and is expected to launch in February 2020.