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Computed tomography in paleopathology Technique and case study.

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AMERICAN JOURNALOFPHYSICALANTHROPOLOGY 55:101- 110(1981)
Computed Tomography in Paleopathology:
Technique and Case Study
PATRICIA A . WONG
Department of Anthropology, University of Utah, Salt Lake City, Utah 84112
Computed tomography, Scan, Density,
KEY WORDS
Desiccation, Contraction of lung tissue, Megacolon,
Hirschsprung disease
ABSTRACT
With the development of computed tomography, soft tissues and
foreign body collections are distinguished with remarkable resolution. This distinction is particularly useful when examining desiccated human remains, both in
construction of research strategies and when invasive procedures (i.e., traditional
autopsies, needle biopsies, etc.)are not possible. Though the organs differ markedly
from living tissue, it is possible to distinguish major organs with some certainty.
One case study exhibited three separate pathological conditions which were not
demonstrated with traditional radiological procedures.
The use of radiographic procedures in paleopathology has proven useful for many decades, but these have, for the most part, been
helpful in distinguishing changes in bone materials rather than soft tissues. With the advent
of other radiographic procedures such as Xeroradiography (see Heinemann, 1976) and computed tomography (Hounsfield, 1973; Harwood-Nash, 19791, we are now able to distinguish the more discrete tissues such as muscles,
soft tissue organs, and foreign body collections
such as cysts, abscesses, and tumors.
This paper describes certain dessicated
human remains which were examined by
means of computed tomography. Cases 1
through 4 were unearthed during the early
1900's by Mormon settlers in southeastern
Utah. The provenience of these remains, thus,
is difficult to assess accurately. Cases 5 and 6
were uncovered during the excavation of Bernheimer Alcove (42SA7361, an archaeological
site which has been cross-dated to the Basketmaker 11-111period (Bernheimer, n.d.).
The usefulness of computed tomography is
not only in visualizing the internal soft tissues
but, perhaps more importantly, as a procedure
that will enable the construction of research
strategies prior to invasive procedures.
MATERIALS AND METHODS
Computed tomography utilizes an x-ray tube
as a source of radiation just as does conventional radiography. It does not, however,
record the image on a fluorescent screen or pho0002-9483/81/5501-0101%03.00
0 1981 ALAN R. LISS, INC.
tographic film. Instead, the radiant energy
traversing the part being examined is measured and from this value is calculated the attentuation (decrease) in energy of the x-ray
beam by the tissue through which it has passed.
As the x-ray attenuation of bone, fat, muscle,
and other tissue are sufficiently different, these
changes can be calculated and ultimately displayed on a viewing monitor (see Brooks and Di
Chiro, 1975).
Radiation detectors are located on the side
opposite the x-ray beam. Both the beam and the
detectors are maintained in a constant spatial
relationship as they are mounted on a common
frame. The Ohio Nuclear Delta 50 model was
used in these procedures and is seen in Figure
1. Between the x-ray beam and the detectors is
the area through which the subject is positioned while on a movable belt.
By rotating the x-ray beam and the detectors,
multiple transmission intensity measurements
are made through the subject. Typically,
thousands of measurements are made for each
degree of the 180"of rotation used in the development of a single image. These measurements, after algorithm translation by the
computer software, permit spatial displays in
the form of anatomic cross sections on the
monitor. From the monitor, Polaroids are taken
and the images can be examined away from the
console.
Received November 7 , 1979; accepted October 2, 1980
102
P.A. WONG
RESULTS
Computed tomographic examinations were
done on the remains of six individuals who
were, in varying degrees in intactness, preserved solely by the very dry environment of
southeastern Utah (Eubank, 1979). One of the
best preserved individuals (Case 1) is a young
female (UMNH 77.20) about 19 years of age,
judging by the skeletal maturation (Lusted and
Keats, 1972). She was unearthed during the
early 1900's and, though no other evidence is
known which would confirm the dating, she is
in the characteristic flexed position (Fig. 1) of
the Basketmaker I1 period (ca. A.D. 1-500)
(Reed, 1964).
The first scan (Fig. 2) is through the midregion of the skull. The tip of the pinna of the
right ear is visualized (a). Dehydrated brain
tissue (b)lying anterior to the internal occipital
protruberance (c)is seen and the sagittal sulcus
is present within this tissue. While this is not a
pathologic condition, it does illustrate the detailed resolution possible using computed
tomography.
Figure 3 is a scan several centimeters lower
than the previous level of Figure 2; it demonstrates the oral pharynx (a), the nasal cavity
(b), and the maxillary sinuses (c) which are all
filled with a dense, amorphous material. The
density of this material is similar to the material found within the stomach (a) in Figure 5 .
Further, though it appears that part of the
esophagus has ruptured or decomposed to the
point of being unrecognizable, this dense material can be found in segments of the remaining
esophagus. This suggests the presence of a
dense material which was ingested and rather
violently aspirated.
Figure 4 (a)demonstrates a contraction of the
left lung, compared to the right (b). Dense material (c) along the left posterior pleural area is
also seen. Conditions such as calcified empyema, which is secondary to inflammatory
disease, such as pneumonia, could produce such
an appearance.
Figure 5 (a) indicates the midportion of the
stomach. The lighter, more dense, area on the
outer part of the stomach is, as has been mentioned, of a density similar to that of the mate-
Fig. 1. ComputedTomography Scanner; (a) x-ray radiationdetectors mounted on common frame opposite (b) x-ray beam;
Case 1 positioned on (c) movable belt.
C.T. IN PALEOPATH TECHNIQUE AND CASE STUDY
Fig. 2.
(a)Ear pinna; (b)brain tissue with sagittal sulcus;
(c) occipital protuberance; (d) falx; (el subdural space.
103
104
P.A. WONG
Fig. 3. (a) Oral pharynx; (b) nasal cavity; (c) maxillary
sinuses.
C.T. IN PALEOPATH: TECHNIQUE AND CASE STUDY
Fig. 4. (a) Contracted left lung tissue; (b) remnants of
right lung tissue not contracted, (c)dense material along left
posterior pleural area.
105
106
P.A. WONG
Fig. 5. (a)Midportion of the stomach with ingested material; (b) distended segment of intestine.
C.T. IN PALEOPATH: TECHNIQUE AND CASE STUDY
Fig. 6. (a)Cross sections of the ascending and descending
portions of the colon at the T12 level.
107
L
Fig. 7. Case #2, distinct visualization of both cerebral
hemispheres and cerebral sulcus.
C.T. IN PALEOPATH: TECHNIQUE AND CASE STUDY
rial found in the sinuses and cavities of the
skull. A segment of the distended intestine (b)
is seen lying laterally to the stomach. This particular segment of the intestine can be followed
up to the level of the elevated diaphragm of the
left lung.
A t the T12 level (Fig. 6),we see the ascending
and descending segments of the colon (a) which
are filled with fecal material and are quite distended. Serial scans all the way to the pelvic
floor demonstrate a continuously distended
colon filled with material of density similar to
that found in the upper intestine.
The obvious question is how this specimen
relates to other desiccated humans and
whether these conditions which have been observed in one individual are pathological or are
normal postmortem conditions. Computed
tomographic scans were made on five other
desiccated individuals. Figure 7 is a scan
through the skull of a young male (BYU 6664.1), case 2, dated to the Pueblo 11 (ca. A.D.
1100-1300) period. The brain tissue of this individual is remarkably distinct, quite unlike
the brain tissue of Case 1. Both cerebral hemispheres and sulci are well-visualized. Scans
were made through the lower abdominal area
and the results differed considerably from
scans in Case 1in that there was no evidence of
distension of the intestine.
Records concerning the provenience of this
individual are vague, though it appears that
he, too, was originally uncovered in the early
1900's in southeastern Utah. The condition of
the brain tissue, as it differs considerably from
others scanned, raises the question of Pueblo
provenience. The difference, of course, could be
explained by differential conditions of preservation.
Case 3 (BYU66-61.61)dated to Basketmaker
I1 and was totally eviscerated, except for the
brain tissue. This condition was unknown prior
to examination by computed tomography.
Case 4 (BYU 66-57.2) was a near or neonatal
infant, of unknown provenience, whose internal organs were too small for adequate visualization, even using a special enlarging program of the Ohio Nuclear computer software.
Case 5 (UMNH 24080 FS91-1) and Case 6
(UMNH 24080 FS90-1)were children (ca.4 and
6 years, respectively) dating to the Basketmaker 11-111period (ca. A.D. 1-750). The intestinal organs of both cases differ considerably
from the distended intestines of Case 1and the
intestinal contents are similar to those of Case
2, tending to support the conclusion that the
distension noted in Case 1is probablypathological and not the result of postmortem changes.
109
DISCUSSION
Hirschsprung disease, first reported in 1887
(Keeferand Mokrohisky, 1954)is apathological
condition characterized by a dilated colon, retention of fecal material, abdominal distension,
and a normal-appearing rectosigmoid region.
The scans of Case 1are characterized by all of
these conditions except that of the normal
rectosigmoid region. Collapse of the sphincter
muscles during the postmortem period may explain the distended rectal region in this young
woman, though confirmation is not possible
with this technique.
This abnormality prevents adequate delivery of feces into the rectum. Classically,
symptoms of congenital megacolon begin a t
birth with constipation and progressive abdominal distension. In modern patients, intermittent relief may be obtained with conservative
management and the degree of severity may be
low enough so that longevity can be extended
into adulthood (Keefer and Mokrohisky, 1954).
A chest radiograph was taken of Case 1and
compared with a chest radiograph of a living
human with confirmed Hirschsprung disease.
Both radiographs demonstrate a distinct flaring of the ribs which may well have been secondary to chronic abdominal distension.
CONCLUSIONS
Through the use of computed tomography, I
have been able to distinguish three conditions
which may be of pathological interest. One
cadaver showed a dense material extending
from the stomach to the oral and nasal cavities,
possibly aspirated after ingestion and perhaps
an agonal event. This technique also demonstrated a contracted lung and possibly calcified
pleura which may have been secondary to inflammation. Finally, we saw the presence of a
megacolon, the most common cause of which is
Hirschsprung disease.
It is, thus, possible to visualize soft tissue
organs of desiccated human remains with computed tomography and, though the organs differ markedly from those of living tissue, it is
possible to distinguish major organs with some
certainty. Furthermore, it is possible to examine human remains when a n invasive procedure is not possible, an important point to consider due t o the sensitive nature of handling
human remains (&sen, 1980). Computed tomography is suggested, therefore, as an excellent method to use either as an initial procedure in a comprehensive examination of
desiccated human remains, allowing the construction of specific research strategies prior to
110
P.A. WONG
an invasive procedure, or as an alternative approach when anatomic examination is not possible.
ACKNOWLEDGMENTS
I thank: PhilipR. Frederick, Gary W. Farnes,
James Cuff, LDS Hospital, Salt Lake City;
Jesse D. Jennings, Dennis Heskel, University
of Utah, Department of Anthropology; Donald
V. Hague, Ann Nelson, Utah Museum of Natural History, Salt Lake City; Dale Berge, Brigh a m Young University, Department of
Anthropology, Provo, Utah.
LITERATURE CITED
Bernheimer, CL (n.d.1Field Notes, Bernheimer Expeditions
of 1922,1923,1924,1926,1927,1929,1930,for the American Museum of Natural History. Manuscript, Utah State
Historical Society. Salt Lake City, Utah.
Brooks, RA, and DiChiro, G (1975) Theory of image reconstruction in computed tomography. Radio I 1 7:561-572.
Eubank, ME (1979) Mark Eubanks Utah Weather. Bountiful, Utah: Horizon Publishers.
Hanvood-Nash, D (1979) Computed tomography of ancient
Egyptian mummies. J. Comput. Assist. Tomogr.
3(6):76%773.
Heinemann, S (1976) Xeroradiography: A new archaeological tool. Am. Ant. 41(1):106111.
Hounsfield, GN (1973) Computerized transverse axial scanning (tomography): Part I. Description of system. Br. J.
Radio 46:1016-1022.
Keefer, GP, and Mokrohisky, JF (1954) Congenital megacolon (Hirschsprung's disease). Radio 63(2):157-174.
Lusted, LB, and Keats, TE (1972)Atlas of roentgenographic
measurement. 3rd ed. Chicago: Year Book Medical Publishers.
Reed, EK (1964)The Greater Southwest. In J D Jennings and
E Norbeck (eds): Prehistoric Man in the New World,
Chicago: University of Chicago Press.
Rosen, L (1980) The excavation of American Indian burial
sites: A problem in law and responsibility. Am. Anthropol.
82(1):5-27.
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