Mummies provide excellent material for research in the fields of

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1 MUMMIES / LES MOMIES Paleoradiology in mummy studies: the Sulman Mummy Project Janet C. Gardner, MA; Greg Garvin, MD, FRCPC; Andrew J. Nelson, PhD; Gian Vascotto, PhD; Gerald Conlogue, MHS, RT,(R)(CT)(MR) Mummies provide excellent material for research in the fields of bioarchaeology and the history of disease. Mummies reach across time and space to tell us about their lives and their cultures. Although many cultures have practiced mummification of human and animal remains, the term mummy generally brings Ancient Egypt to mind. 1 The popular perception of the process of mummification is heavily shaped by the writings of Herodotus, but in fact there was a great deal of variation in Egyptian funeral rites. The first Egyptian mummies (ca BC) were naturally desiccated in the desert sands. 2 Artificial mummification developed to improve levels of preservation, thereby maintaining a form as lifelike as possible to allow the soul to survive in the afterlife. 3 The variation in mummification methods tells us much about the mummy s time period and the social status of the individual in life. The fact that these individuals have been preserved for many thousands of years allows us to retrieve information about health and disease, as well as about their daily lives and their funerary rituals. In this paper, we describe a previously unreported, ongoing and collaborative paleoradiologic project focused on an Egyptian mummy, involving researchers from the Department of Anthropology at the University of Western Ontario (UWO), St. Joseph s Health Care, Robarts Research Institute and the National Research Council of Canada s Virtual Environment Technologies Centre (VETC), London, Ont. This project mirrors the evolution of paleoradiology in mummy studies, from basic plain film images to the latest 3-dimensional (3D) reconstructions based on computed tomography (CT). THE USE OF RADIOLOGY IN MUMMY STUDIES There are 2 areas of interest to investigators in the paleoradiologic study of mummies. 4 The first area combines the related fields of paleopathology, bioarchaeology and the history of medicine. Questions asked in this realm might include the following: Are the mummified remains those of an animal or a human? If human, what was the sex, stature and age at death of this individual? Did they have fractures or pathologic lesions? The second area of interest is focused on the archaeological or cultural context of the specimen. Questions asked in this realm could include the following: How were they embalmed? Are any artifacts preserved? What can we tell about the daily life of this individual? The application of paleoradiologic methods allows the researcher to address these questions without having to unwrap and, in the process, destroy the mummy. Radiology and mummy studies have always been closely intertwined. Only 1 year after the discovery of x-rays in 1896, radiography was used to examine the contents of an Egyptian coffin at the Museum of Natural History in Vienna. The radiographs demonstrated that the contents were not Gardner, Nelson Department of Anthropology, University of Western Ontario, London; Garvin Department of Radiology, St. Joseph s Health Care, London; Vascotto Virtual Environment Research Centre, Integrated Manufacturing Technologies Institute, National Research Council, London, Ont.; Conlogue Diagnostic Imaging Program, Quinnipiac University, Hamden, Conn. Address for correspondence: Dr. Andrew J. Nelson, Department of Anthropology, Social Science Centre, University of Western Ontario, London ON N6A 5C2; fax ; anelson@uwo.ca Submitted Mar. 30, 2004 Accepted May 17, 2004 Can Assoc Radiol J 2004;55(4): JACR VOL. 55, N o 4, OCTOBRE Canadian Association of Radiologists

2 PALEORADIOLOGY IN MUMMY STUDIES human as originally thought; rather, the coffin contained an ibis. 5 Simple plain film radiography has always had an important role to play in mummy studies. It is affordable, accessible and mobile, and it should be the first step in any survey of a mummy specimen. Portable, basic radiographic equipment allows for field studies and the examination of specimens in situ. 6 Excellent examples of large-scale studies using simple radiographic techniques are the well-known Manchester Mummy Project 7 and the University of Chicago survey of the Royal Mummies. 8 Recently, with the development of new imaging techniques, radiologic investigations have shown increasing value in studies of mummies. 4,9 The first computed tomographic scan of an Egyptian mummy was conducted in Toronto in Cross-sectional display, high spatial and contrast resolution, and multiplanar as well as 3D reconstruction make CT an extremely useful imaging technology for studying mummies. CT allows for detailed visualization of the body, the internal contents and associated artifacts, which are often not visible on conventional radiography. 9 Mummies can be repeatedly virtually unwrapped and dissected, which allows for accurate and detailed documentation of human remains. The potential for cranial and facial reconstruction has only begun to be realized by creating 3D reconstructions from CT data using computer graphic programs. 11 CT data files can also be used for the rapid production of stereolithographic models and 3D prints of fragile anthropological skeletal and mummified specimens Other modern sophisticated imaging techniques have limited usefulness in mummy studies. For instance, the desiccated condition of mummified remains generally limits the utility of ultrasonography and magnetic resonance imaging. However, magnetic resonance images have proved to be useful in visualizing the neural anatomy of an ancient Peruvian mummy. 15 Institute during conservation of the wrappings; and then twice by our team in 2001 and 2003 (Fig. 1). The most recent radiologic studies began in 2001 when a team from Engel Brothers Media came to Chatham to film an episode of The Mummy Road Show (shown on National Geographic s cable channel). This opportunity arose through previous collaborations between one of the members of the Road Show team (J.C.) and an anthropologist at the University of Western Ontario (A.J.N.). As part of this production, a radiographic series was undertaken, including anteroposterior (AP), lateral and oblique views of the mummy (Fig. 1). In 2003, project members began advanced CT studies and 3D and virtual reconstructions of the Sulman mummy (Fig. 2). These studies allowed us to obtain more detailed osteological and archaeological data about the mummy, including conservation conditions, THE SULMAN MUMMY: A CASE STUDY IN PALEORADIOLOGY The research outlined here includes paleoradiologic studies and the virtual reconstruction of the Sulman mummy, an Egyptian mummy from the Ptolemaic period (ca. 200 BC), currently housed in the Chatham Kent Museum in Chatham, Ont. The mummy was brought to Canada in the 1920s by the Sulman family of Chatham. The mummy is preserved intact, including its wrappings and cartonnage. The cartonnage is a 5-element decoration made of plasterimpregnated linen that adorns the top of the mummy and was originally incorporated in with the wrappings. Over the past 85 years, the mummy has been radiographed 4 times: first, in the 1920s by a local physician; in the 1980s by the Canadian Conservation FIG. 1: Composite radiographic images of the Sulman mummy. The first radiographs were obtained in the 1920s by the Chatham surgeon Dr. T.K. Holmes. More radiographs were taken in the 1980s by the Canadian Conservation Institute, as part of a conservation project. The most recent radiographs were obtained in 2001 by members of this research team. Note the fact that many skeletal elements are out of anatomical position, but that they have been stable over the past 80 years and more. CARJ VOL. 55, NO. 4, OCTOBER

3 GARDNER ET AL assessment of sex, estimation of stature and age, and the identification of artifacts and other foreign objects, and of anatomical abnormalities or pathologic indicators. The recent literature includes many descriptions of the use of radiography and CT (including 3D reconstructions) of mummies. 3 5,11 14,16 However, it is our belief that this is the first long-term research project explicitly designed to combine traditional and cutting edge radiologic imaging modalities with 3D laser scanning in order to undertake a paleopathologic and archaeological analysis of an Egyptian mummy in concert with the construction of a virtual model of the entire mummy and a facial reconstruction. The chronological series of radiographs from the 1920s to 2001 (Fig. 1) gave the team an important opportunity to examine the effects that the recent history of the mummy has had on the physical remains. Plain film radiographs revealed that, while the mummy is essentially intact, many of the individual bones are out of anatomical position. The condition of the Sulman mummy before its purchase is unknown; however, since the time it left Egypt it has travelled thousands of miles and has been positioned both vertically and horizontally. An important curatorial question was whether this manipulation had contributed to the shifting of the bones. The resolution of this question would have implications for any further analysis of the mummy; if manipulation had resulted in disturbance of the skeleton, then any further movement, even to take the mummy to a CT scanner, might not be permissible. Fortunately, a comparison of the radiograph series revealed that the malpositioned bones had maintained their position within the mummy bundle since the 1920s. A possible explanation was suggested when an attempt to introduce an endoscope into the right thoracic area of the mummy was defeated by an abundant amount of loose, raw cotton. Such stuffing has not been previously documented as a common mummification practice. Rather, it is quite likely that the mummy was actually in a poor state of preservation in the late 1800s or early 1900s and was then stuffed and rewrapped in preparation for the tourist trade, which was quite active at this time. In this scenario, the bones would have moved out of place before the rewrapping took place, at which time they would have been fixed in place by the cotton and new wrappings. Thus, the team determined that the mummy s skeleton was now quite stable and could be moved with care. This conclusion allowed us to bring the mummy to London, Ont., for CT and laser scanning. Later, the analysis of the computed tomographic images shed additional light on this scenario, as the images indicated that there are several layers of wrappings and that the deeper layers are not continuous (Fig. 3). In addition, the computed tomographic images showed evidence of an extra roll of wrapping that was left between the thighs, which was not evident in the conventional images. The skewed position of the innominates within the bundle made sex determination difficult using standard AP radiographic views. A radiologist who read the x- ray films in the 1980s suggested that the individual FIG. 2: Three-dimensional (3D) reconstruction of the Sulman mummy as rendered on the General Electric (GE) workstation. 230 JACR VOL. 55, N o 4, OCTOBRE 2004

4 PALEORADIOLOGY IN MUMMY STUDIES was male. This conclusion conflicted with the original information supplied to the Sulman family at the time of purchase, when they were told the mummy was a princess. In 2001, new radiographic views were obtained by placing a portable x-ray source in a position oblique to the mummy, perpendicular to the pubis, with the film positioned perpendicular to the x- ray source. The resulting image revealed subpubic morphology indicative of the female sex. Sex assessment from the computed tomographic images and subsequent 3D segmented reconstructions of the pelvic area completed at the VETC allowed us to rotate the FIG. 3: Midabdominal computed tomographic (CT) image shows residual and distinct organs in the pelvic cavity. The arrow at the top of the figure shows external intact wrappings, whereas the lower arrow shows an area where cotton has been stuffed in and not wrapped in layers. innominates in virtual space, giving us a view that confirmed the team s assessment that the mummy is, in fact, female. Whether or not the mummy was of royal status, as the label princess implies, required the consideration of other osteological details, such as stature, pathology and indicators of stress. Egyptian royal mummies are generally described as being tall. An AP view of the tibia from the 2001 radiographs was measured for the estimation of stature. The application of anthropometric formulae, with adjustments made for magnification, yielded a height estimate of 161 cm. Measurements taken from the computed tomographic data later confirmed this estimate. This stature would be considered to be short in any Egyptian population. Overall, the Sulman mummy appears to be in good bony health, although there is indication of mild degenerative disease as demonstrated by the presence of osteophytic lipping on some of the thoracic and lumbar vertebrae. Radiopaque lines of arrested growth (Harris lines) on the tibiae indicate multiple episodes of stress due to nutritional deficiency or childhood disease. Thus, we concluded that the evidence of cyclical childhood stress and overall short stature was not consistent with patterns demonstrated by Egyptian royalty, although the lack of advanced degeneration of the skeleton indicated that this individual had not been a labourer. The Sulman mummy was most likely to have been a member of the Egyptian middle class. The Sulman mummy s social status is FIG. 4: Midsagittal CT slice shows an intact ethmoid plate and residual brain matter in the posterior part of the skull. FIG. 5: This lateral plain film gave the first indication of the presence of foreign objects on the mummy. The upper oval highlights the low-density hollow structures that appear to be wrapped around the upper portion of the skull. The lower oval highlights the denser chain at the base of the skull. CARJ VOL. 55, NO. 4, OCTOBER

5 GARDNER ET AL not inconsistent with the fact that her body had been mummified, because during the Ptolemaic period everyone whose family could mobilize sufficient financial resources was mummified. The analysis of the radiographs and computed tomographic images yields additional information about the mummification techniques practised at the time. Many Egyptian mummies show signs of the removal of the brain through the nose. 1,4 In addition, the internal organs were often removed, wrapped into organ packs and returned to the body, or stored separately in canopic jars. In the case of the Sulman mummy, residual brain material is visible on the radiographs as a cloudy mass in the cranium. This identification is confirmed by clearly visible sulci on the CT slices. The presence of an intact ethmoid plate (Fig. 4) confirms that the Sulman mummy was not subject to the removal of the brain through the nasal passage as evidenced in other Egyptian mummies. An area of increased density was noted in the right upper quadrant of the abdomen on the radiographs, possibly representing an organ pack. However, the CT images did not reveal any such bundles, showing only the presence of some fragments of untreated desiccated organs (Fig. 3). Insights into the adornment of this mummy were also provided by radiography. Two sets of small opaque circular objects were noted on the lateral cranial plain film (Fig. 5). Axial CT slices showed what appeared to be a string of large beads behind the right ear (Fig. 6). 3D reconstruction revealed that this ornament was probably a chain that followed the curvature of the skull (Fig. 7) between the skull and the first layer FIG. 7: Detailed 3D reconstruction of the chain around the mummy s head shows that it is a series of ring-shaped loops. FIG. 6: Axial CT slice of the skull with the arrow indicating the dense chain-like object, located behind the right ear, curving around the occiput. FIG. 8: 3D print of the Sulman mummy s skull that was used for the facial reconstruction (Z-Corp 406 printer, courtesy of The Drafting Clinic, Mississauga, Ont.). 232 JACR VOL. 55, N o 4, OCTOBRE 2004

6 PALEORADIOLOGY IN MUMMY STUDIES of wrappings. Density values suggest that it is metallic. There are also many small, hollow, low-density structures that appear to be wrapped around the head (Fig. 5). Jewellery was commonly placed on the bodies of deceased Egyptians before wrapping, 1 and the location of these objects seems to suggest that this mummy was wearing a headband decorated with beads. The volume rendering of the CT slices into 3D reconstructions allowed the team to confirm the general condition, body position and sex of the mummy, embalming practices, and the presence and location of artifacts. Furthermore, manipulation of the CT data by researchers at the VETC produced a 3D digital model of the skull. Physical models of the skull were then produced using 3D printing (Fig. 8) and stereolithography. The 3D print model was used as the basis of a forensic facial reconstruction of the mummy, as executed by the noted portrait artist Christian Cardell Corbet (Fig. 9, Fig. 10). The cartonnage and the external surface characteristics of the wrappings were captured using a laser scanner and colour camera combination. These were then reconstructed as 3D stereo images. These data were then processed and, when combined with the CT data, allowed the virtual reconstruction of the entire Sulman mummy. The mummy is, thus, reconstructed as a virtual representation that can be viewed in a variety of 3D stereo environments. Using the advanced imaging equipment at the VETC, including a 4-wall CAVE (a high-resolution, virtual-reality 3D video environment), it is possible to be completely immersed in the mummy s structure or do a virtual unwrapping and fly-through of the mummy. In this environment, the virtual mummy can also be disassembled. Individual skeletal elements can be selected, rotated and used to obtain accurate measurements. The digital 3D models are now in a format that allows distribution to researchers through digital media to be observed in a variety of readily available viewers and on the desktop. CONCLUSION The relatively intact and well-preserved condition of FIG. 9: Facial reconstruction in progress (by Christian Cardell Corbet, artist). FIG. 10: Completed facial reconstruction (by Christian Cardell Corbet, artist). CARJ VOL. 55, NO. 4, OCTOBER

7 GARDNER ET AL the Sulman mummy makes it highly suitable for noninvasive, paleoradiologic studies. The team s experience and the extensive body of relevant literature demonstrate that imaging studies play a fundamental role in the study of mummified and archaeological remains. History has shown that advances in imaging technology, from the original discovery of x-rays to the latest 3D rendering of CT images, rapidly move from the clinical realm to the analysis of ancient human remains. The cooperation of anthropologists, archaeologists, radiologists and computer design engineers improves our knowledge of human history and serves to preserve the integrity of human and archaeological remains. ACKNOWLEDGEMENTS: The Sulman (or Chatham) mummy is housed at the Chatham Kent Museum in Chatham, Ont. The collaboration and cooperation of the staff of the museum, including Tanya Neave, Dave Benson, Stephanie Suitor and Deanna Bullard, and many volunteers has been critical to the success of this project. Mr. George Sulman has been very supportive of this undertaking. Work on the Chatham mummy has proceeded in 2 phases. In the first phase, a sequence of plain film radiographs was taken as part of an episode for the television series, The Mummy Road Show. The research team included Jerry Conlogue and Ron Beckett of the Bioanthropology Institute at Quinnipiac University, Hamden, Conn.; Rita Downhill, Chatham Kent Health Alliance; David Holdsworth, Robarts Research Institute, London; Christine Nelson, City of London; Stan Kogon, University of Western Ontario (UWO) School of Dentistry, London; and UWO Anthropology Graduate Students Marla Toyne and Marc Lichtenfeld. Staff members of the Canadian Museum of Civilization (CMC) and the Canadian Conservation Institute (CCI) also generously cooperated with this project, by sharing reports and radiographs from their 1980s conservation project. We thank Ian Wainwright and Tom Stone of the CCI and Jerome Cybulski of the CMC. The Engel Brothers Production team included Larry Engel, Mary Olive Smith and Alana Campbell. The second phase of the project included the laser and computed tomographic scanning, the production of the virtual mummy and the facial reconstruction of the Chatham mummy. Team members included Rosemary Millar, Kathy Wilkins and Don Taves, St. Josephs Health Care, London; Lesley Short, UWO Faculty of Dentistry; Christian Cardell Corbet, portrait artist; Brian Grunté, photographer; Shawn Kelly, The Drafting Clinic Canada Limited; David Holdsworth, Robarts Research Institute; Ellie Withers, Niall Murray and Steve Kruithof, Virtual Environment Technologies Centre, Integrated Manufacturing Technologies Institute, National Research Council. This phase of the project was featured in 2 episodes of the Daily Planet, Discovery Channel Canada, produced by Jane Mingay and Cindy Bahadur. The team leader would also like to acknowledge the use of the facilities of the Bioarchaeological Research Facility in the Department of Anthropology at the UWO. This facility has been funded by grants from the Canada Foundation for Innovation (CFI), the Ontario Innovation Trust, the UWO s Academic Development Fund, and through the ongoing efforts of the UWO Alumni Association. 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