domingo, 18 de diciembre de 2011

Estudios sobre la momia Fleming

En este artículo se exponen los estudios realizados a la llamada momia Fleming y como gracias a la radiologia consiguen averiguar datos importantes sobre la misma.

Radiology Helps Unwrap Mummy Mystery

In November 2010, the radiology lab at Fletcher Allen Health Care received its most unusual patient to date. Her identification? "Fleming Mummy," an object from the university museum's permanent collection.

"I guess we won't put down her date of birth," said Dr. Jason Johnson to Taunya Perron, who assisted with the mummy's CT scan. As five people from the Fleming Museum, two radiologists, a photographer, a radiology physicist, and two CT technologists looked on, a pre-recorded voice spoke up: "Take a deep breath in, and hold your breath," to much laughter.

Why was the Fleming's mummy visiting the hospital? The request to take the CT came from Johnson. Intrigued since 6th grade by Egyptology and enamored of archaeology equally as long (with credit due to Indiana Jones, he says), Johnson had read about scans taken in 2009 of a mummy at the Boston Museum of Fine Arts. After meeting with Dr. Ravij Gupta, the radiologist who worked on the case in Boston, Johnson approached the Fleming with the hope that advances in imaging technology -- and specifically CT -- could reveal more about their mummy, which hadn't been imaged since 1937 when portable radiographs were performed in the museum.

The museum, happy to learn more about one of its most popular objects, accepted.

What did they already know? "The Fleming Museum acquired the mummy in 1910," says Aimee Marcereau DeGalan, museum curator. "Dean George Henry Perkins, who was the university's first curator, traveled to Egypt and bought the mummy from the museum in Cairo. He then had it shipped back, and we've had it ever since." While her birth date isn't known, a general sense of her age is. "The mummy's from the third intermediate period, or the 25th dynasty, which makes her about 2,700 years old," says DeGalan. The earlier x-rays had determined that she was female and likely 14- to 16-years-old at the time of her death.

But radiology has come a long way since the first scans 70 years ago. In addition to more powerful technology, radiologists are only recently learning about how to optimize CT scans for a non-living subject.

"Radiation protection is very important in living humans," says Johnson, "but this concern was completely inapplicable to this situation. So we were able to do two things: we were able to use a much higher radiation dose and also use much thinner slices than we would typically use on living patients to examine them. So the end result is we have very high resolution of the scans and very crisp pictures."

In January, the scans were shared by Johnson with a room full of experts -- a group comprising anthropologists, museum staff, medical examiners, and a forensic dentist. As Johnson scrolled through the images -- the mummy's skull, its disjointed jaw bone, a pile of bone fragments (likely what remains of her hands), as well as an unidentified circular object near her midsection (perhaps a decorative plate?) -- the researchers asked questions and reflected on what they were seeing.

Of most interest was the mummy's cause of death. Could it be determined now that clearer pictures of her bones were available? The experts focused on a skull fracture -- also seen in the original x-rays, but visible now from a variety of angles, as Johnson turned and rotated the three-dimensional images. While it's not possible to say decisively that it was the cause of her demise, the fracture, as state medical examiner Steve Shapiro noted, shows little to no evidence of healing, meaning it was sustained within a week or two prior to death or post-mortem.

Another benefit of the detailed CT scans is the ability to see inside of the mummy's skull to have a look at the delicate bone structure within that has largely remained intact. The significance of this, Johnson says, relates to the practice of removing the brain, a procedure ubiquitous in Egyptian mummification. One of the most well known methods -- through the nose -- was the first to be considered.

"Everything's intact there," said Steven Shapiro, chief medical examiner for the State of Vermont, referring to the nasal bones. "They probably didn't go through the nose with anything." Also intact, Johnson noted, was the back of the skull. Surgically created holes at the back of the head were another exit route used by mummifiers.

This leaves the foramen magnum, Latin for "great hole," or the large opening in the base of the skull through which the spinal cord passes. The scans indicate that the top two cervical vertebrae are missing, offering access to the cranial vault where the brain resides, making the foramen magnum the most likely route used during mummification.

Since that meeting, the scholars have continued to review the scans, searching for clues that will help them shed light on the identity of the mummy, the events surrounding her death, and the mummification process.

UVM anthropologist Deborah Blom says that looking through the scans is "almost like excavating. You have layers and layers in the scans, and you're going through and trying to determine what might be in there -- whether it's bone, remnants of the mummification process, like wrappings, soft tissue, or any kind of offering." Those layers, she says, provide a better look at the contents than flat images ever could. For example, the CT scans allow cross-sectional views of the bones, which, because of the way bone adapts to the stress it's put under during repeated use, might give researchers the opportunity to learn more about activitity patterns during the mummy's life.

Blom, along with two other experts, forensic dentist David Averill and Jennifer Prutsman-Pfeiffer, a forensic anthropologist from the University of Rochester, have corroborated the mummy's age. According to Averill's look at the development of her third molars, her age was likely to have been 15 at the time of her death (the mean age in a range of 12-18). Prutsman-Pfeiffer places her at 12-15-years-old, based on the non-fusion of the distal femoral epihysis and the fusion of the proximal tibia ephysis in her knees.

As hypotheses continue to be formed by those collaborating on the project, the Fleming will collect the findings, bolstering the knowledge they provide to classes that study the mummy as well as preparing an exhibit around the project, tentatively slated for next year.

One piece that will be a part of that exhibit is a three-dimensional model of the mummy's skull, created at UVM's Instrumentation and Model Facility using Johnson's scans.

"It's one thing to see a 2-D scan or an image, but to see the skull gives people a better sense of the physicality of the object," says Marcereau DeGalan. "Being able to see the size of her skull, her teeth -- it offers one more point of connection for people with a figure that's literally shrouded in mystery."

The high-resolution scans, says Johnson, are a critical tool in reconstructing a story about past lives. In clinical settings, he says, doctors have the ability to ask a patient, "What happened to your head?" But in this case, when all you have are bones to tell the story, the more level of detail you can capture, the better.

Because of the work on the mummy, "We've changed the way we do forensic scans in the department," says Johnson, referring to a series of optimizing changes they've made on the settings of the CT machine. "We really pushed the technology available to us here at Fletcher Allen and the University of Vermont to maximize the ability to look inside this mummy in a non-destructive manner."

Imágenes de la momia Fleming

hay una colección de imágenes en el encale, aquí cuelgo alguna:

No hay comentarios:

Publicar un comentario