Lena Öhrström - Academia.edu (original) (raw)

Papers by Lena Öhrström

Research paper thumbnail of CT-Based Assessment of Relative Soft-Tissue Alteration in Different Types of Ancient Mummies

Anatomical record (Hoboken, N.J. : 2007), 2015

Mummification leads to alteration of soft-tissue morphology. No research has focused specifically... more Mummification leads to alteration of soft-tissue morphology. No research has focused specifically on differences in soft-tissue shrinkage depending on mummification type. This study evaluated whether soft-tissue alteration is dependent on type of mummification. A total of 17 human mummies have been investigated by computed tomography (CT). Samples included artificially embalmed ancient Egyptian mummies, naturally mummified South American corpses, ice mummies (including the Iceman, South Tyrol Museum of Archeology, Bolzano, Italy, ca. 3,300 BC), bog bodies and a desiccated mummy of possibly Asian provenance. The acquired data were compared to four contemporary bodies. The extent of soft-tissue shrinkage was evaluated using CT data. Shrinkage was defined as soft-tissue relative to area of bone (in number of voxels). Measurements were taken at 13 anatomically defined locations. Ice mummies show the highest degree of preservation. This finding is most likely explained due to frozen wate...

Research paper thumbnail of Shedding New Light on the 18th Dynasty Mummies of the Royal Architect Kha and His Spouse Merit

PloS one, 2015

The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes ... more The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes near the ancient workers' village of Deir el-Medina. Previous MDCT (this abbreviation needs spelling out) investigations showed that the bodies of Kha and Merit did not undergo classical royal 18th Dynasty artificial mummification, which included removal of the internal organs. It was, therefore, concluded that the retention of the viscera in the body, combined with an absence of canopic jars in the burial chamber, meant the couple underwent a short and shoddy funerary procedure, despite their relative wealth at death. Nevertheless, all internal organs - brain, ocular bulbs/ocular nerves, thoracic and abdominal organs - showed a very good state of preservation, which contradicts the previous interpretation above. In order to better understand the type of mummification used to embalm these bodies, both wrapped mummies were reinvestigated using new generation X-ray imaging and chemical...

Research paper thumbnail of Body height of mummified pharaohs supports historical suggestions of sibling marriages

American Journal of Physical Anthropology, 2015

Body height is an important factor in reconstructing health conditions and it serves as an indica... more Body height is an important factor in reconstructing health conditions and it serves as an indicator of socio-economic status. Researchers rely on ancient data to analyze evolutionary aspects of human health and its interrelation with environmental influences. This study presents body height estimates from all periods of ancient Egyptian history and compares the general population with the existing mummies of the members of royal families. A sample of 259 adult Egyptian mummies originating from various collections and published sources with body lengths (long bone measures or/and overall measurements, CT data) were analyzed, and royal mummies were scored with respect to the level of consanguinity. Male royals were taller than males in the general ancient Egyptian population, while female royals were shorter than females in the general population. The body height variation of the royals is significantly reduced when compared with a pool of non-royal mummies. This provides evidence for inbreeding resulting from consanguineous marriages. However, there appears to be no correlation between the level of inbreeding and individual body height. The random sample of general population does not show signs of inbreeding. Due to the present lack of larger, technically and ethically challenging genetic studies, the selected non-invasive approach of body height is the most reliable indicator of sibling marriages of pharaohs based on direct physical evidence. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc.

Research paper thumbnail of Radiological findings in an ancient Iranian salt mummy (Chehrābād ca. 410-350 BC)

Skeletal Radiology, 2015

To study pathologies, peri- and postmortal alterations as well as the general preservation state ... more To study pathologies, peri- and postmortal alterations as well as the general preservation state of an ancient Iranian salt mummy. Several mummified remains from two different time periods (1500-2500 BP) were found in the Chehrābād salt mine in Iran. Computed tomography was performed on Salt Man #4 (410-350 BC), the best preserved out of the six salt mummies (Siemens, Sensation 16; 512 × 512 matrix; 0.75-5 mm slice thickness, 240-mA tube current, 120-kV tube voltage, and 0.976-mm pixel size). Radiological analyses showed an excellent state of preservation of an adolescent body. Several normal variants such as aplasia of the frontal sinus as well as a rare congenital deformation of the 5th vertebral body (butterfly vertebra) have been observed. The individual shows multiple fractures, which is consistent with the theory that he died due to a collapse in the ancient salt mine. The salt preserved the soft tissue as well as parts of the inner organs remarkably well. However, further investigations including histology are needed to reveal additional details of the health status of this unique salt mummy.

Research paper thumbnail of Scenes from the Past: MR Imaging versus CT of Ancient Peruvian and Egyptian Mummified Tissues

RadioGraphics, 2013

Ancient Egyptian and Peruvian mummies are extremely valuable historical remains, and noninvasive ... more Ancient Egyptian and Peruvian mummies are extremely valuable historical remains, and noninvasive methods for their examination are desirable. The current standard of reference for radiologic imaging of mummies is computed tomography (CT), with tissue having a homogeneous appearance on all CT images. It was long believed that ancient mummified tissue could not be studied with magnetic resonance (MR) imaging because of the low water content in mummies. Recently, however, the usefulness of MR imaging in the evaluation of mummified tissue was demonstrated for the first time, with use of a special ultrashort echo time technique. The authors of the present study acquired and analyzed MR imaging and CT data from the left hands of two ancient Egyptian mummies and the head of a third Egyptian mummy (ca 1500-1100 bce), as well as data from an ancient Peruvian mummy (ca 1100 ce). CT was found to provide superior detail of the anatomic structures, mainly because of its higher spatial resolution. The signal intensity of mummified tissue varied greatly on MR images; thus, the quality of these images is not yet comparable to that of clinical MR images, and further research will be needed to determine the full capacity of MR imaging in this setting. Nevertheless, additional information may theoretically be obtained with MR imaging, which should be viewed as complementary to, rather than a replacement for, CT.

Research paper thumbnail of Confirmation of microevolutionary increase in spina bifida occulta among Swiss birth cohorts

European Spine Journal, 2011

Previous studies on the prevalence of spina bifida occulta have indicated a microevolutionary inc... more Previous studies on the prevalence of spina bifida occulta have indicated a microevolutionary increase in its frequency and possible population differences in the prevalence of the condition. We studied the frequencies of closed and open sacral canals at each sacral level among two birth cohorts in Switzerland. Transverse CT scans and multiplanar reconstruction images of sacra of 95 males and 96 females born in 1940-1950 and 99 males and 94 females born in 1970-1980 in Switzerland were reviewed. We found that individuals born later have significantly more open sacral arches at all sacral levels compared to those born 30-40 years earlier. When results were related to previously published data on Australian cohorts, the trend was the same, but Swiss in both cohorts were less likely to have an open section than Australians at all locations apart from S2. This study confirmed a microevolutionary trend in the opening of sacral canal among two different generations in Switzerland and demonstrated a population difference in the prevalence of spina bifida occulta.

Research paper thumbnail of Technical note: Terahertz imaging of ancient mummies and bone

American Journal of Physical Anthropology, 2010

Ancient mummified soft-tissues are a unique source to study the evolution of disease. Diagnostic ... more Ancient mummified soft-tissues are a unique source to study the evolution of disease. Diagnostic imaging of such historic tissues is of foremost interest in paleoanthropology or paleopathology, with conventional x-ray and computed tomography (CT) being the gold-standard. Longer wavelength radiation in the far-infrared or Terahertz region allows diagnostic close-to-surface tissue differentiation of bone morphology while being harmless to human cells. The aim of this study is to show the feasibility and the morpho-diagnostic impact of THz imaging of historic remains. Images of an artificially embalmed ancient Egyptian human mummy hand, an artificially embalmed ancient Egyptian mummified fish and a macerated human lumbar vertebra were obtained by THz-pulse imaging and compared with conventional X-ray and CT images. Although conventional x-ray imaging provides higher spatial resolution, we found that THz-imaging is well-suited for the investigation of ancient mummified soft tissue and embalming-related substances / wrappings. In particular, bone and cartilaginous structures can be well differentiated from surrounding soft-tissues and bandage-wrappings by THz imaging. Furthermore, THz-pulse imaging also measures the time-delay of the pulsed signal when passing through the sample, which provides supplementary information on the optical density of the sample that is not obtained by X-ray and CT. Terahertz radiation provides a completely non-invasive diagnostic imaging modality for historic dry specimens. We anticipate this modality also to be used for detection of hidden objects in historic samples such as funerary amulets still in situ in wrapped mummies, as well as potentially for the identification of spectral signatures from chemical substances, e.g., in embalming essences.

Research paper thumbnail of Terahertz imaging modalities of ancient egyptian mummified objects and of a naturally mummified rat

Anatomical record (Hoboken, N.J. : 2007), 2015

During the last few years, terahertz (THz) imaging has been used to investigate artwork and histo... more During the last few years, terahertz (THz) imaging has been used to investigate artwork and historic artifacts. The application of THz imaging to mummy investigations is very attractive since it provides spectroscopic information over a broad frequency range and its radiation has proven to be harmless to human cells. However, compared with the current standard imaging methods in mummy imaging-X-ray and computed tomography (CT)-it remains a novel, emerging technique whose potential still needs to be fully evaluated. Here, ancient Egyptian mummified objects as well as a naturally mummified rat have been investigated by two different THz imaging systems: a broadband THz time domain imaging system and an electronic THz scanner. The obtained THz images are compared with conventional CT, X-ray, and magnetic resonance images. While the broadband THz time domain setup permits analyses of smaller samples, the electronic THz scanner allows the recording of data of thicker and larger samples a...

Research paper thumbnail of CT-Based Assessment of Relative Soft-Tissue Alteration in Different Types of Ancient Mummies

Anatomical record (Hoboken, N.J. : 2007), 2015

Mummification leads to alteration of soft-tissue morphology. No research has focused specifically... more Mummification leads to alteration of soft-tissue morphology. No research has focused specifically on differences in soft-tissue shrinkage depending on mummification type. This study evaluated whether soft-tissue alteration is dependent on type of mummification. A total of 17 human mummies have been investigated by computed tomography (CT). Samples included artificially embalmed ancient Egyptian mummies, naturally mummified South American corpses, ice mummies (including the Iceman, South Tyrol Museum of Archeology, Bolzano, Italy, ca. 3,300 BC), bog bodies and a desiccated mummy of possibly Asian provenance. The acquired data were compared to four contemporary bodies. The extent of soft-tissue shrinkage was evaluated using CT data. Shrinkage was defined as soft-tissue relative to area of bone (in number of voxels). Measurements were taken at 13 anatomically defined locations. Ice mummies show the highest degree of preservation. This finding is most likely explained due to frozen wate...

Research paper thumbnail of Shedding New Light on the 18th Dynasty Mummies of the Royal Architect Kha and His Spouse Merit

PloS one, 2015

The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes ... more The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes near the ancient workers' village of Deir el-Medina. Previous MDCT (this abbreviation needs spelling out) investigations showed that the bodies of Kha and Merit did not undergo classical royal 18th Dynasty artificial mummification, which included removal of the internal organs. It was, therefore, concluded that the retention of the viscera in the body, combined with an absence of canopic jars in the burial chamber, meant the couple underwent a short and shoddy funerary procedure, despite their relative wealth at death. Nevertheless, all internal organs - brain, ocular bulbs/ocular nerves, thoracic and abdominal organs - showed a very good state of preservation, which contradicts the previous interpretation above. In order to better understand the type of mummification used to embalm these bodies, both wrapped mummies were reinvestigated using new generation X-ray imaging and chemical...

Research paper thumbnail of Body height of mummified pharaohs supports historical suggestions of sibling marriages

American Journal of Physical Anthropology, 2015

Body height is an important factor in reconstructing health conditions and it serves as an indica... more Body height is an important factor in reconstructing health conditions and it serves as an indicator of socio-economic status. Researchers rely on ancient data to analyze evolutionary aspects of human health and its interrelation with environmental influences. This study presents body height estimates from all periods of ancient Egyptian history and compares the general population with the existing mummies of the members of royal families. A sample of 259 adult Egyptian mummies originating from various collections and published sources with body lengths (long bone measures or/and overall measurements, CT data) were analyzed, and royal mummies were scored with respect to the level of consanguinity. Male royals were taller than males in the general ancient Egyptian population, while female royals were shorter than females in the general population. The body height variation of the royals is significantly reduced when compared with a pool of non-royal mummies. This provides evidence for inbreeding resulting from consanguineous marriages. However, there appears to be no correlation between the level of inbreeding and individual body height. The random sample of general population does not show signs of inbreeding. Due to the present lack of larger, technically and ethically challenging genetic studies, the selected non-invasive approach of body height is the most reliable indicator of sibling marriages of pharaohs based on direct physical evidence. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc.

Research paper thumbnail of Radiological findings in an ancient Iranian salt mummy (Chehrābād ca. 410-350 BC)

Skeletal Radiology, 2015

To study pathologies, peri- and postmortal alterations as well as the general preservation state ... more To study pathologies, peri- and postmortal alterations as well as the general preservation state of an ancient Iranian salt mummy. Several mummified remains from two different time periods (1500-2500 BP) were found in the Chehrābād salt mine in Iran. Computed tomography was performed on Salt Man #4 (410-350 BC), the best preserved out of the six salt mummies (Siemens, Sensation 16; 512 × 512 matrix; 0.75-5 mm slice thickness, 240-mA tube current, 120-kV tube voltage, and 0.976-mm pixel size). Radiological analyses showed an excellent state of preservation of an adolescent body. Several normal variants such as aplasia of the frontal sinus as well as a rare congenital deformation of the 5th vertebral body (butterfly vertebra) have been observed. The individual shows multiple fractures, which is consistent with the theory that he died due to a collapse in the ancient salt mine. The salt preserved the soft tissue as well as parts of the inner organs remarkably well. However, further investigations including histology are needed to reveal additional details of the health status of this unique salt mummy.

Research paper thumbnail of Scenes from the Past: MR Imaging versus CT of Ancient Peruvian and Egyptian Mummified Tissues

RadioGraphics, 2013

Ancient Egyptian and Peruvian mummies are extremely valuable historical remains, and noninvasive ... more Ancient Egyptian and Peruvian mummies are extremely valuable historical remains, and noninvasive methods for their examination are desirable. The current standard of reference for radiologic imaging of mummies is computed tomography (CT), with tissue having a homogeneous appearance on all CT images. It was long believed that ancient mummified tissue could not be studied with magnetic resonance (MR) imaging because of the low water content in mummies. Recently, however, the usefulness of MR imaging in the evaluation of mummified tissue was demonstrated for the first time, with use of a special ultrashort echo time technique. The authors of the present study acquired and analyzed MR imaging and CT data from the left hands of two ancient Egyptian mummies and the head of a third Egyptian mummy (ca 1500-1100 bce), as well as data from an ancient Peruvian mummy (ca 1100 ce). CT was found to provide superior detail of the anatomic structures, mainly because of its higher spatial resolution. The signal intensity of mummified tissue varied greatly on MR images; thus, the quality of these images is not yet comparable to that of clinical MR images, and further research will be needed to determine the full capacity of MR imaging in this setting. Nevertheless, additional information may theoretically be obtained with MR imaging, which should be viewed as complementary to, rather than a replacement for, CT.

Research paper thumbnail of Confirmation of microevolutionary increase in spina bifida occulta among Swiss birth cohorts

European Spine Journal, 2011

Previous studies on the prevalence of spina bifida occulta have indicated a microevolutionary inc... more Previous studies on the prevalence of spina bifida occulta have indicated a microevolutionary increase in its frequency and possible population differences in the prevalence of the condition. We studied the frequencies of closed and open sacral canals at each sacral level among two birth cohorts in Switzerland. Transverse CT scans and multiplanar reconstruction images of sacra of 95 males and 96 females born in 1940-1950 and 99 males and 94 females born in 1970-1980 in Switzerland were reviewed. We found that individuals born later have significantly more open sacral arches at all sacral levels compared to those born 30-40 years earlier. When results were related to previously published data on Australian cohorts, the trend was the same, but Swiss in both cohorts were less likely to have an open section than Australians at all locations apart from S2. This study confirmed a microevolutionary trend in the opening of sacral canal among two different generations in Switzerland and demonstrated a population difference in the prevalence of spina bifida occulta.

Research paper thumbnail of Technical note: Terahertz imaging of ancient mummies and bone

American Journal of Physical Anthropology, 2010

Ancient mummified soft-tissues are a unique source to study the evolution of disease. Diagnostic ... more Ancient mummified soft-tissues are a unique source to study the evolution of disease. Diagnostic imaging of such historic tissues is of foremost interest in paleoanthropology or paleopathology, with conventional x-ray and computed tomography (CT) being the gold-standard. Longer wavelength radiation in the far-infrared or Terahertz region allows diagnostic close-to-surface tissue differentiation of bone morphology while being harmless to human cells. The aim of this study is to show the feasibility and the morpho-diagnostic impact of THz imaging of historic remains. Images of an artificially embalmed ancient Egyptian human mummy hand, an artificially embalmed ancient Egyptian mummified fish and a macerated human lumbar vertebra were obtained by THz-pulse imaging and compared with conventional X-ray and CT images. Although conventional x-ray imaging provides higher spatial resolution, we found that THz-imaging is well-suited for the investigation of ancient mummified soft tissue and embalming-related substances / wrappings. In particular, bone and cartilaginous structures can be well differentiated from surrounding soft-tissues and bandage-wrappings by THz imaging. Furthermore, THz-pulse imaging also measures the time-delay of the pulsed signal when passing through the sample, which provides supplementary information on the optical density of the sample that is not obtained by X-ray and CT. Terahertz radiation provides a completely non-invasive diagnostic imaging modality for historic dry specimens. We anticipate this modality also to be used for detection of hidden objects in historic samples such as funerary amulets still in situ in wrapped mummies, as well as potentially for the identification of spectral signatures from chemical substances, e.g., in embalming essences.

Research paper thumbnail of Terahertz imaging modalities of ancient egyptian mummified objects and of a naturally mummified rat

Anatomical record (Hoboken, N.J. : 2007), 2015

During the last few years, terahertz (THz) imaging has been used to investigate artwork and histo... more During the last few years, terahertz (THz) imaging has been used to investigate artwork and historic artifacts. The application of THz imaging to mummy investigations is very attractive since it provides spectroscopic information over a broad frequency range and its radiation has proven to be harmless to human cells. However, compared with the current standard imaging methods in mummy imaging-X-ray and computed tomography (CT)-it remains a novel, emerging technique whose potential still needs to be fully evaluated. Here, ancient Egyptian mummified objects as well as a naturally mummified rat have been investigated by two different THz imaging systems: a broadband THz time domain imaging system and an electronic THz scanner. The obtained THz images are compared with conventional CT, X-ray, and magnetic resonance images. While the broadband THz time domain setup permits analyses of smaller samples, the electronic THz scanner allows the recording of data of thicker and larger samples a...