Fatal gunshot to a fox_ The Virtopsy approach in a

Journal of Forensic Radiology and Imaging ∎ (∎∎∎∎) ∎∎∎–∎∎∎
Contents lists available at ScienceDirect
Journal of Forensic Radiology and Imaging
journal homepage: www.elsevier.com/locate/jofri
Case report
Fatal gunshot to a fox: The Virtopsy approach in a forensic veterinary case
Sabine Franckenberg a,n, Fabian Kern b, Michael Vogt c, Michael J. Thali a, Patricia M. Flach a
a
b
c
Institute of Forensic Medicine, University of Zurich, Winterthurerstrasse 190/52, Zurich 8057, Switzerland
Forensic Institute of Zurich, Zeughausstrasse 11, Zurich 8004, Switzerland
Vogtwaffen, Wehntalerstrasse 6, Oberglatt 8154, Switzerland
art ic l e i nf o
a b s t r a c t
Article history:
Received 13 October 2014
Accepted 6 November 2014
A four-month-old male fox shot dead by a hunter was subjected to unenhanced postmortem computed
tomography (PMCT), PMCT-angiography (PMCTA) and magnetic resonance imaging (PMMR) to document the effects of semi-jacketed hunting ammunition (.17 Hornet) on the body of a small animal.
The effect of the ammunition on bone structures (crushing of the cervical spine and spinal cord), blood
vessels (laceration of all supra-aortal vessels) and surrounding soft tissue (large wound cavity) was
extensive, and imaging confirmed the fatal power of the ammunition. Virtual autopsy (Virtopsy) is a
valuable examination tool for veterinary indications as well as in humans.
& 2014 Elsevier Ltd. All rights reserved.
Keywords:
Virtopsy
Veterinary pathology
PMCT
MRI
PMCTA
Hunting ammunition
Ballistic
1. Introduction
2. Materials and methods
At present, hunting involves a broad range of services because
both the ecological and economic aspects of agriculture and
forestry must be considered. The strategic goals of hunting include
sustaining the biodiversity and habitats of feral mammals, birds
and fish; protecting endangered species; preventing damage to the
environment; and inhibiting imbalances in wildlife stock [1].
These goals are regulated by federal law [2], whereas the beginning and end of hunting seasons and ammunition regulations are
dictated by cantonal law [1] in Switzerland.
To reduce an overwhelmingly increasing fox population, a fourmonth-old male fox was shot by a hunter in the hunting district
Stallikon II, canton of Zurich, Switzerland. The animal was delivered to the Institute of Forensic Medicine, University of Zurich,
Zurich, Switzerland, 1 day after death for a veterinary-adapted
virtual autopsy (Virtopsy) to visualize the internal findings [3–5].
The veterinary virtual autopsy procedure, adapted from postmortem radiological examination methods, has been previously
described [6]. The purpose of this case study was to evaluate the
destructive effects and fatal power of the semi-jacketed hunting
ammunition (.17 Hornet) in small animals.
The four-month-old male red fox (Vulpes vulpes) was shot by
a hunter the night before the examination from a distance
of approximately 130 m. The rifle used was a Savage Model 25
(Savage Arms™, New York, USA) with a 3–9 50 mm rifle scope
(Hawke Sport Optics, Suffolk, United Kingdom) (Fig. 1a). The semijacketed ammunition used was .17 Hornet 20 gr V-Maxs (Hornadys
Manufacturing Company, Grand Island, USA) (Fig. 1b and c). There
was no activity involving live animals at any stage in the development of this work or production of this paper.
Unenhanced postmortem computed tomography (PMCT) and
PMCT-angiography (PMCTA) were performed at the Institute of
Forensic Medicine, University of Zurich, Zurich, Switzerland, using
a dual-source CT scanner (SOMATOM Flash Definition, Siemens,
Forchheim, Germany). The scan parameters were as follows: a tube
voltage of 120 kVp; automatic dose-modulation software (CARE
Dose 4D, Siemens, Forchheim, Germany); a slice thickness of
.6 mm; an increment of .6 mm; and reconstructions in soft,
medium and hard kernels using consecutive bone and soft-tissue
windows [7].
Preparation for PMCTA included vascular access to the arterial
and venous system via unilateral inguinal incision and the dissection of the femoral vessels with subsequent retrograde cannulation of the femoral artery and antegrade cannulation of the
femoral vein. The applied mixture of contrast media was the same
as that used for human PMCTA, which has been previously
described in the literature [8,9].
n
Corresponding author at: Department of Forensic Medicine and Imaging,
Institute of Forensic Medicine, University of Zurich, Winterthurerstrasse 190/52,
8057 Zurich, Switzerland
E-mail address: [email protected] (S. Franckenberg).
http://dx.doi.org/10.1016/j.jofri.2014.11.001
2212-4780/& 2014 Elsevier Ltd. All rights reserved.
Please cite this article as: S. Franckenberg, et al., Fatal gunshot to a fox: The Virtopsy approach in a forensic veterinary case, Journal of
Forensic Radiology and Imaging (2014), http://dx.doi.org/10.1016/j.jofri.2014.11.001i
2
S. Franckenberg et al. / Journal of Forensic Radiology and Imaging ∎ (∎∎∎∎) ∎∎∎–∎∎∎
Fig. 1. (A) Photograph of the hunting rifle: Savage Model 25. (B) Photograph of the semi-jacketed ammunition:.17 Hornet 20 gr V-Maxs by Hornady. (C) 3-Dimensional
postmortem computed tomography reconstruction of the scanned ammunition.
Fig. 2. Whole-body postmortem computed tomography reconstruction of the fox. (a) 3-Dimensional surface reconstruction with entry wound (red circle). (b) 3-Dimensional
reconstruction of the skeleton. Note the radiodense content of the intestines, corresponding to partially digested bones (green circle), as foxes devour their prey whole.
(c) 3-Dimensional reconstruction of radiodense structures such as bones, teeth and metallic fragments. The projectile fragments in the neck and upper thoracic region
present a high density and are therefore colored in blue (as are the teeth). (d) Maximum intensity projection reconstructions of the head, neck and upper thorax in a view
from the right side. Note the widespread distribution of bullet fragments (white particles inside the green circle) within the neck and upper thoracic region. Comminuted
fractures representing the total destruction and dislocation of the cervical spine and myelon are indicated by the yellow dotted line.
Unenhanced PMMR was performed using a 3T MRI (Achieva
3.0T TX MRI, Philips, Best, Netherlands) for a whole-body scan,
including coronal, sagittal and transverse (all with a slice thickness
of 2.5 mm) T2- and T1-weighted sequences and steady short tau
inversion recovery (STIR) sequences. Specific T2-weighted neck
sequences were obtained with a 2 mm slice thickness in sagittal,
coronal and transverse orientations. PMMR was performed prior
to PMCTA. Image review and 3D reconstructions were performed
on a PACS workstation (IDS7, Sectra AB, Linköping, Sweden) and
a client-server platform using syngo.via (Siemens, Forchheim,
Germany).
3. Results
3.1. Postmortem computed tomography (PMCT)
Unenhanced whole-body PMCT reconstruction revealed the
entry wound (Fig. 2a), the bony content of the intestines, the
presence of which can be attributed to the fox devouring its prey
whole (Fig. 2b), and a broad distribution of projectile fragments
within the neck and upper thoracic region (Fig. 2c). The entry
wound was in the right neck region and contained perforating and
penetrating metallic projectile fragments. No soot was detected in
Please cite this article as: S. Franckenberg, et al., Fatal gunshot to a fox: The Virtopsy approach in a forensic veterinary case, Journal of
Forensic Radiology and Imaging (2014), http://dx.doi.org/10.1016/j.jofri.2014.11.001i
S. Franckenberg et al. / Journal of Forensic Radiology and Imaging ∎ (∎∎∎∎) ∎∎∎–∎∎∎
the PMCT images. The projectile particles accumulated predominantly around the 5th and 6th cervical vertebrae and were
scattered within a region of approximately 8.2 13.3 6.3 cm3.
The lower cervical spine displayed comminuted fractures of the
4th to 7th cervical vertebrae and transection of the cervical
myelon (Fig. 2d). The apical portions of the lung displayed
traumatic pneumatoceles, bilateral extensive pneumothorax and
slight pneumomediastinum caused by partially scattered fragments and pressure-related injuries to the upper chest. Additionally, both lungs exhibited round, more peripherally located lesions
(up to 4 mm in diameter) that can most likely be attributed to an
infectious or parasitic disease such as the lungworm Crenosoma
vulpis or similar [10]. The proximal esophagus was lacerated and
exhibited disruption. The entire gastrointestinal tract displayed
hyperdense particles corresponding to digested flesh and bone
3
fragments. No old fractures were detected, and the epiphyseal
plates were not yet closed, indicative of the youth of the red fox.
The injuries did not lead to a fatal gas embolism.
3.2. Postmortem magnetic resonance imaging (PMMR)
Postmortem magnetic resonance imaging facilitated the detection of the myelon transection and the tracheal lesion (Fig. 3).
In addition, the large wound cavity, located predominantly on the
right upper thoracic aperture and neck, was distinct. In addition,
there was subcutaneous and intramuscular hemorrhage. The
metallic projectile fragments produced few susceptibility artifacts
and still allowed for sufficient radiological interpretation.
Fig. 3. Postmortem magnetic resonance imaging (PMMR). Cranial is to the right. (a) Sagittal detail scan of head and neck (T2-weighted sequence) with a thinner slice
thickness. The complete disruption of the spine (green dotted line) and myelon (red dotted line) is distinct in the PMMR images, as are the extensive soft-tissue edema
(hyperintense in the T2-weighted sequence) and the hematoma (yellow asterisk) within the large wound cavity (blue circle). (b) Volume rendering of the head and neck
region of the PMMR. The white-colored region indicated by the blue circle represents the large hemorrhage within the wound cavity.
Fig. 4. Postmortem computed tomography angiography (PMCTA) of the fox. Cranial is to the top. (a) View from the ventrocaudal side of the head, neck and torso in a
3-Dimensional reconstruction of the PMCTA image data (arterial and venous injection). (b) Detail view from the ventrocaudal side of the upper thoracic aperture and neck.
The aortic arch (yellow arrow) and superior caval vein (blue arrow) exhibit no disruption or leakage in the PMCTA images. The large hematoma, indicated by a large amount
of contrast medium mixture, is indicated by a green asterisk and can be attributed to the destruction of the cervical spine, myelon, soft tissue and vessels. The green circle
indicates the extent of the observed scattering of dense particles, which consist predominantly of projectile particles and multiple osseous fragments. (c) Detail view of a
maximum intensity projection (MIP) of the upper thoracic and neck region from ventrocaudal. The contrast medium extravasation attributed to the vascular injury of all
major cervical vessels is distinctly visible (green asterisk), as are the projectile particles (green circle).
Please cite this article as: S. Franckenberg, et al., Fatal gunshot to a fox: The Virtopsy approach in a forensic veterinary case, Journal of
Forensic Radiology and Imaging (2014), http://dx.doi.org/10.1016/j.jofri.2014.11.001i
S. Franckenberg et al. / Journal of Forensic Radiology and Imaging ∎ (∎∎∎∎) ∎∎∎–∎∎∎
4
3.3. Postmortem computed tomography angiography (PMCTA)
Contrast-enhanced PMCTA (Fig. 4) revealed a large, expanding
hematoma within the soft-tissue emphysema on the right thoracic
side, extending proximally to the 5th cervical vertebra on the right
and leading to an alteration of the cervical diameter. In the PMCTA
images, airway dissection of the trachea became visible because of
the extravasation of the contrast mixture into the distal trachea.
All supra-aortal arteries and both jugular veins were lacerated and
exhibited considerable contrast medium extravasation. Because of
the extravasation of the contrast media into the trachea and the
esophageal disruption, some fluid accumulation (contrast medium
mixture) was visible within the small intestines in the PMCTA
images.
distance and accuracy in targeting an anatomical region that is
then highly likely to induce the immediate and painless death of
the hunted animal.
5. Conclusion
Virtopsy of animals provides not only spectacular insight into
the anatomy of the mammals but also aids in the evaluation of
hunting-related and veterinary issues and the determination of
the cause and manner of death without the need for any manual
dissection. In this case, the radiological examination provided a
clear answer to the posed question and allowed for virtual in situ
visualization of the pathologies.
4. Discussion
Postmortem imaging allowed for the determination of the
cause and manner of death in the deceased fox. The distinct and
clearly fatal impact of the semi-jacketed hunting ammunition (.17
Hornet 20 gr V-MAXs by Hornady) could be easily visualized.
Among hunters, there is an ongoing discussion regarding whether
this semi-jacketed ammunition truly causes the rapid and
“humane” death of the prey animal, without inducing unnecessary
suffering. This case report yields an answer to this question that is
clearly affirmative. The single shot, aimed at the upper thorax
and neck region, thoroughly crushed vital structures such as the
cervical myelon and all supra-aortal vessels, as observed via
imaging. PMCTA was especially useful in determining the exact
structures that were injured. The large wound cavity within the
soft tissue and the pattern of the scattered bony and projectile
fragments served as additional indicators of the fatal efficacy of
this specific ammunition.
The fox did not sustain a fatal gas embolism, which, as a socalled “vital sign,” would be an indicator of a (prolonged) agonal
interval. From the point of view of forensic pathology, the
sustained injuries and the lack of a gas embolism are clear
evidences of the immediate incapacitation and death of the fox.
Imaging and external inspection did not reveal any soot on the
skin, supporting the hunter's claim of a long-range shooting
distance.
Nonetheless, in addition to proper ammunition, hunters must
always consider many other factors, such as variation in shooting
References
[1] Jagd Jagdverwaltung F-u, 2014. Available from: 〈http://www.aln.zh.ch/internet/
baudirektion/aln/de/fjv/Jagd.html〉.
[2] BdS Eidgenossenschaft. Bundesgesetz über die Jagd und den Schutz wild
lebender Säugetiere und Vögel, 1986. Available from: 〈http://www.admin.ch/
opc/de/classified-compilation/19860156/index.html〉.
[3] M.J. Thali, M. Braun, U. Buck, E. Aghayev, C. Jackowski, P. Vock, et al., VIRTOPSY—
scientific documentation, reconstruction and animation in forensic: individual
and real 3D data based geo-metric approach including optical body/object
surface and radiological CT/MRI scanning, J. Forensic Sci. 50 (2005) 428–442.
[4] Virtopsy. The virtopsy project, 2014. Available from: 〈http://www.virtopsy.com〉
(cited 01.06.02).
[5] M.J. Thali, K. Yen, W. Schweitzer, P. Vock, C. Boesch, C. Ozdoba, et al., Virtopsy, a
new imaging horizon in forensic pathology: virtual autopsy by postmortem
multislice computed tomography (MSCT) and magnetic resonance imaging
(MRI)—a feasibility study, J. Forensic Sci. 48 (2003) 386–403.
[6] M.J. Thali, B.P. Kneubuehl, S.A. Bolliger, A. Christe, U. Koenigsdorfer, C. Ozdoba,
et al., Forensic veterinary radiology: ballistic-radiological 3D computertomographic reconstruction of an illegal lynx shooting in Switzerland, Forensic Sci.
Int. 171 (2007) 63–66.
[7] P.M. Flach, D.Gascho, W. Schweitzer, T.D. Ruder, N. Berger, S.G. Ross, et al.,
Imaging in forensic radiology: an illustrated guide for postmortem computed
tomography technique and protocols. Forensic Sci. Med. Pathol.. 2014.
[8] S.G. Ross, S.A. Bolliger, G. Ampanozi, L. Oesterhelweg, M.J. Thali, P.M. Flach,
Postmortem CT angiography: capabilities and limitations in traumatic and
natural causes of death, Radiographics 34 (2014) 830–846.
[9] S. Ross, D. Spendlove, S. Bolliger, A. Christe, L. Oesterhelweg, S. Grabherr, et al.,
Postmortem whole-body CT angiography: evaluation of two contrast media
solutions, Am. J. Roentgenol. 190 (2008) 1380–1389.
[10] A. Nevarez, A. Lopez, G. Conboy, W. Ireland, D. Sims, Distribution of Crenosoma
vulpis and Eucoleus aerophilus in the lung of free-ranging red foxes (Vulpes
vulpes), J.Vet. Diagn. Investig. 17 (2005) 486–489.
Please cite this article as: S. Franckenberg, et al., Fatal gunshot to a fox: The Virtopsy approach in a forensic veterinary case, Journal of
Forensic Radiology and Imaging (2014), http://dx.doi.org/10.1016/j.jofri.2014.11.001i