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False positive aortic dissection on postmortem computed tomography
Forensic Science International 254 (2015) e4–e6
Contents lists available at ScienceDirect
Forensic Science International journal homepage: www.elsevier.com/locate/forsciint
Case report
False positive aortic dissection on postmortem computed tomography Isabelle Le Blanc-Louvry a,*, Sophie Thureau a, Kathy Ledoux a, Benjamin Mogdad a, Emma Lagroy a, Jean Nicolas Dacher b, Gilles Tournel a a b
Department of Forensic Medicine, Rouen University Hospital-Charles Nicolle, 1 rue de Germont, 76031 Rouen Cedex, France Radiological Department, Rouen University Hospital-Charles Nicolle, 1 rue de Germont, 76031 Rouen Cedex, France
A R T I C L E I N F O
A B S T R A C T
Article history: Received 3 March 2015 Received in revised form 12 June 2015 Accepted 15 June 2015 Available online 23 June 2015
Post-mortem CT-scan (PMCT) has become increasingly useful as a diagnostic tool. However, certain normal postmortem changes may mimic the appearance of pathologic findings. We report two cases of false positive aortic dissection. Methods: Non-contrast PMCT was performed on a sixty-four-detector row scanner. Each PMCT examination was assessed and reported by two independent radiologists. Autopsies were performed according European recommendations. Cases: In two corpses, a false positive DeBakey type I aortic dissection was detected. Autopsies confirmed that CT findings were artifactual. For each case the cause of the mistake was individually discussed and mainly based on the abnormalities observed during the autopsy. In fact, in our series (750 PMCT) a true aortic dissection was detected in two corpses during the same period. Conclusion: When a PMCT is performed, false positive aortic dissection can occur, which confirms the interest in combining opacification. ß 2015 Published by Elsevier Ireland Ltd.
Keywords: Forensic radiology Postmortem computed tomography Diagnostic error Aortic dissection
1. Introduction At the beginning of the 21st century, post-mortem CT-scanning (PMCT) was introduced in several centers, particularly in US [1], Switzerland [2] and France [3]. PMCT has several advantages compared to traditional autopsy because this procedure is objective, rapid and storable for the future. In clinical studies, CT-angiography is considered the gold standard to diagnose aortic dissection. Nevertheless, the rate of false positive diagnosis of aortic dissection is reported to be 10% on CT-angiography [4]. First, occasionally normal anatomic structures may be misconstrued as being pathologic due to a lack of familiarity with anatomical variations [5,6]. False positive diagnoses can also result in cases where extra-aortic structures (e.g. aortic sinus, mediastinal veins, thickened pleura) are mistaken for false channels in the aorta [7] or when mediastinal tumors can be confused with dissection flaps [8]. Therefore, several conditions can lead to false positive diagnoses of aortic dissection by CT-scan even when CT-scan with a contrast medium is performed. Also when a PMCT is achieved, the fact that many artifacts due to blood elements sedimentation, intravascular clots and
* Corresponding author. Tel.: +33 2 32 88 82 84; fax: +33 2 32 88 86 76. E-mail address: [email protected] (I. Le Blanc-Louvry). http://dx.doi.org/10.1016/j.forsciint.2015.06.014 0379-0738/ß 2015 Published by Elsevier Ireland Ltd.
putrefaction are present, induces even more difficulties to interpret the vascular abnormalities, especially when non-contrast PMCT is carried out. Thus, as previously reported there is a difficulty in confirming the presence of an aortic dissection by PMCT [9]. In one case Kluschke et al. reported a case of a ruptured abdominal aortic aneurysm associated with ambiguous accessory findings on PMCT suggestive of thoracic aortic dissection, but not confirmed by autopsy: this pseudo-dissection was probably caused by sedimented and coagulated blood [10]. This report concerns two cases of false positive aortic dissection and illustrates potential errors as well as discusses their mechanisms. 2. Methods 2.1. Post-mortem CT-scanning Each corpse was wrapped in two artifact-free body bags. In both cases, the CT-scan allowed to completely explore the entire body including both the upper limbs and lower limbs. The examinations were performed on a sixty-four-detector CT scanner (Discovery 750HD, General Electric HealthCare1). The examination started with anterior-posterior and lateral scout views of the whole body including the head. Acquisition parameters for body scanning were: tube voltage 120 kVp, current
I. Le Blanc-Louvry et al. / Forensic Science International 254 (2015) e4–e6
intensity 200 mA, field of view 50 cm, slice thickness/increment 1.25 mm/1.25 mm. Images were then transferred to an ‘‘Advantage’’ (ADW, General Electric HealthCare1) work-station. A routine software (Reformat1) allowed multiplanar (conventional and oblique) reconstruction.
e5
Finally, among the 750 PMCT that to date were performed, four diagnoses of DeBakey type I aorta dissection were carried out, including only two that were confirmed by autopsy. When an aorta dissection was present, the images were identical to those obtained in the absence of dissection. Moreover, even after a second reading, no difference could be observed.
2.2. Autopsy Autopsies were routinely performed by two experienced forensic experts. Anatomical dissection was carried out according to European recommendations. 2.3. Radiological evaluation and data analysis PMCT was assessed by a radiologist who was aware of the circumstances of death. A second reading was performed by another radiologist who was blinded to the results of the previous radiological analysis. These radiologists have previously been involved in the reading of all the 750 cases performed in our hospital. 3. Cases 3.1. Case 1 PMCT was performed two days after death. On the axial and sagittal views through the thorax obtained in the corpse, an aspect of hyperdensity of the wall of the ascending aorta was observed (Fig. 1). However, during the autopsy, no dissection was observed, but a voluminous peri- and retroaortic abscess due to a parietal thoracic tumor that infiltrated the surrounding tissues. Moreover, after autopsy, when all the images were read again, a left axillary peripheral tissue infiltration was observed. 3.2. Case 2 On the axial images obtained three days after the death, an intramural hematoma appeared to be present in the wall of the ascending aorta (Fig. 2). Moreover, a fatty line seemed to separate the false lumen from the true lumen. Flap appearance in the ascending part of aorta also appeared to be present on sagittal images. However, the autopsy did not show any aortic dissection, but only a prevertebral cervical and thoracic hematoma due to several cervical vertebral fractures.
4. Discussion In this study we report two cases where PMCT findings were misinterpreted as an aortic dissection. The images mimiced an intramural hematoma similar to those found after DeBakey type I aortic dissections. These findings are interesting because it shows pit-falls in postmortem imaging that is essential to improve the quality of postmortem radiology in general. In fact, the lack of vascular contrast on non-contrast PMCTs and the presence of postmortem changes i.e. clotting or sedimentation, misinterpretation of PMCT findings are not rare [10]. If misdiagnosis of aortic dissection, secondary to motion artifact simulating an intimal flap in the ascending aorta, occurs in clinical practice [4,6–9], this type of mistake can in fact more frequently be found during post-mortem examination due to the lack of opacification and the presence of putrefaction artifacts such as clotting or sedimentation. Thus, often when the false lumen is not opacified, differentiation among a thrombus-filled atherosclerotic aneurysm, thrombosed dissection or intramural hematoma is difficult. As regards both of our reported cases, even though PMCT examinations were performed with a reliable multidetector CT (sixty-four-detector row scanner) that increases spatial and temporal resolution, nevertheless, without opacification, aortic dissection appeared to be present. In both cases, a cause was found to explain the erroneous diagnosis of dissection. In case 1, a main peri- and retro aortic abscess was highlighted. Therefore, false aortic dissection images were probably due to the presence of an inflammation of the surrounding tissues that induced a thickening of the aortic wall. In fact, periaortic fibrosis, but also mediastinal or pulmonary retroperitoneal tumors, can be mistaken for aorta dissection [8,11]. Similarly, in case 2, a prevertebral cervical and thoracic hematoma due to several cervical vertebral fractures may have led to a tissue modification that could have been confused with aorta dissection [8,11]. Then, on PMCT imaging, false positive diagnoses
Fig. 1. On these axial (A1) and sagittal (A2) images through the thorax obtained by PMCT in the corpse (case 1), an hyperdensity (arrow) of the wall of the ascending aorta mimics an aortic dissection. The autopsy found a voluminous peri- and retroaortic abscess due to a parietal thoracic tumor without dissection.
e6
I. Le Blanc-Louvry et al. / Forensic Science International 254 (2015) e4–e6
Fig. 2. On this axial image (A1), an intramural hematoma (single arrow) seems to be present in the wall of the ascending aorta (case 2). Moreover, a fatty line (double-arrow) seems separate a false lumen from a true lumen. Flap-like appearance in the ascending part of aorta (single arrow) is present on this sagittal image (A2). No dissection was found during autopsy but a prevertebral hematoma due to cervical vertebral skulls.
of aorta dissection were linked to artifacts created by pathologic tissues directly surrounding this vascular segment. Regarding one particular case, Schwendener et al. drew attention to the difficulty in affirming the presence of an aortic dissection by PMCT [9]. These authors explained that only a presumptive diagnosis of type II aortic dissection based on an anterior mediastinal enlargement could be performed. In addition, one report was related to a false positive diagnosis of thoracic aortic dissection associated with a true image of ruptured abdominal aortic aneurysm (confirmed by the autopsy), the pseudo-dissection being probably caused by sedimented and coagulated blood [10]. Finally, Ampanozi et al. reported that, in 76% (25/33) of their cases, signs which are indicative for aortic dissection (dislocated calcification, intimal-medial flap, double sedimentation level in true and false lumen) could be identified using a non-enhanced PMCT [12]. This suggests that specific training and education could be useful to improve the diagnostic accuracy based on this approach. Thus, in our experience, the false positive result may have been related to the limited experience of our radiologists in detecting aortic dissection on PMCT (2 aortic dissections/750 PMCT performed). Finally, due to the poor accuracy of PMTC to detect vascular abnormalities [1,13], opacification should be useful, even if the basic limit is the high costs of the equipment when the radiological examination is performed using a modified heart-lung machine [14]. An alternative would be to perform PMCT angiographies via a catheter inserted into the femoral artery using echography guidance. An article, regarding only one case, demonstrated the feasibility of this technique using a standard CT injector [15]. In conclusion, our cases illustrate some potential errors in detecting aorta dissection during PMCT. Misinterpretation can be avoid by the knowledge that abnormalities as an abscess or hematoma in the tissues around the aorta can mimic an aortic dissection, and also by a greater experience of the radiologists. Acknowledgement The authors are grateful to Richard Medeiros, Medical EditorRouen University Hospital, for editing the manuscript.
References [1] G. Levy, L. Goldstein, A. Blachar, S. Apter, E. Barenboim, Y. Bar-Dayan, A. Shamais, E. Atar, Postmortem computed tomography in victims of military air mishaps: radiological–pathological correlation of CT findings, Isr. Med. Assoc. J. 9 (2007) 699–702. [2] M.J. Thali, C. Jackowski, L. Oesterhelweg, S.G. Ross, R. Dirnhofer, VIRTOPSY—the Swiss virtual autopsy approach, Leg. Med. 9 (2007) 100–104. [3] I. Le Blanc-Louvry, S. Thureau, C. Duval, F. Papin-Lefebvre, J. Thiebot, J.N. Dacher, C. Gricourt, E. Toure´, B. Proust, Post-mortem computed tomography: compared to forensic autopsy findings—a French experience, Eur. Radiol. 23 (2013) 1829–1835. [4] C.E. Raymond, B. Aggarwal, P. Schoenhagen, D.M. Kralovic, K. Kormos, D. Holloway, V. Menon, Prevalence and factors associated with false positive suspicion of acute aortic syndrome: experience in a patient population transferred to a specialized aortic treatment center, Cardiovasc. Diagn. Ther. 3 (2013) 196–204. [5] M.A. McMahon, A. Squirrell, Multidetector CT of aortic dissection: a pictorial review, Radiographics 30 (2010) 445–450. [6] G. Shanmugam, J. McKeown, M. Bayfield, N. Hendel, C.C. Hughes, False positive computed tomography findings an aortic dissection, Heart Lung Circ. 13 (2004) 184–187. [7] J.D. Godwin, R.S. Breiman, J.M. Speckman, Problems and pitfalls in the evaluation of thoracic aortic dissection by computed tomography, J. Comput. Assit. Tomogr. 6 (1982) 750–776. [8] C. Sebastia, E. Pallisa, S. Quiroga, A. Alvarez-Castelis, R. Dominguez, A. Evandelista, Aortic dissection: diagnosis and follow up with helical CT, Radiographics 19 (1999) 45–50. [9] N. Schwendener, M. Mund, C. Jackowski, Type II DeBakey dissection with complete aortic rupture visualized by unenhanced postmortem imaging, Forensic Sci. Int. 225 (2013) 67–70. [10] F. Kluschke, S. Rosse, P.M. Flach, W. Schweitzer, G. Ampanozi, D. Gascho, B. Vonlanthen, M.J. Thali, T.D. Ruder, To see or not to see—ambiguous findings on post-mortem cross-sectional imaging in a case of ruptured abdominal aortic aneurysm, Leg. Med. 15 (2013) 256–259. [11] K.M. Nelsen, D.L. Spizarry, D.J. Kastan, Intimointimal intussusception in aortic dissection: ct diagnosis, Am. J. Roentgenol. 162 (1994) 813–814. [12] G. Ampanozi, P.M. Flach, J. Fornaro, S.G. Ross, W. Schweitzer, M.J. Thali, T.D. Ruder, Systematic analysis of the radiologic findings of aortic dissections on unenhanced postmortem computed tomography, Forensic Sci. Med. Pathol. 11 (2015) 162–167. [13] S.A. Bolliger, M.J. Thali, S. Ross, U. Buck, S. Naether, P.P. Vock, Postmortem imaging-guided biopsy as an adjuvant to minimally invasive autopsy with CT and postmortem angiography: a feasibility study, Am. J. Roentgenol. 195 (2010) 1051–1056. [14] S. Grabherr, F. Doenz, B. Steger, R. Dirnhoher, A. Dominguez, B. Sollberger, E. Gygax, E. Rizzo, C. Chevallier, R. Meuli, P. Mangin, Multi-phase post-mortem CT angiography: development of a standardized protocol, Int. J. Legal Med. 25 (2012) 791–802. [15] M. Jolibert, F. Cohen, C. Bartoli, C. Boval, V. Vidal, J.Y. Gaubert, G. Moulin, P. Petit, J.M. Bartoli, G. Leonetti, G. Gorincour, Postmortem CT-angiography: feasibility of US-guided vascular access, J. Radiol. 92 (2011) 446–449.
Contents lists available at ScienceDirect
Forensic Science International journal homepage: www.elsevier.com/locate/forsciint
Case report
False positive aortic dissection on postmortem computed tomography Isabelle Le Blanc-Louvry a,*, Sophie Thureau a, Kathy Ledoux a, Benjamin Mogdad a, Emma Lagroy a, Jean Nicolas Dacher b, Gilles Tournel a a b
Department of Forensic Medicine, Rouen University Hospital-Charles Nicolle, 1 rue de Germont, 76031 Rouen Cedex, France Radiological Department, Rouen University Hospital-Charles Nicolle, 1 rue de Germont, 76031 Rouen Cedex, France
A R T I C L E I N F O
A B S T R A C T
Article history: Received 3 March 2015 Received in revised form 12 June 2015 Accepted 15 June 2015 Available online 23 June 2015
Post-mortem CT-scan (PMCT) has become increasingly useful as a diagnostic tool. However, certain normal postmortem changes may mimic the appearance of pathologic findings. We report two cases of false positive aortic dissection. Methods: Non-contrast PMCT was performed on a sixty-four-detector row scanner. Each PMCT examination was assessed and reported by two independent radiologists. Autopsies were performed according European recommendations. Cases: In two corpses, a false positive DeBakey type I aortic dissection was detected. Autopsies confirmed that CT findings were artifactual. For each case the cause of the mistake was individually discussed and mainly based on the abnormalities observed during the autopsy. In fact, in our series (750 PMCT) a true aortic dissection was detected in two corpses during the same period. Conclusion: When a PMCT is performed, false positive aortic dissection can occur, which confirms the interest in combining opacification. ß 2015 Published by Elsevier Ireland Ltd.
Keywords: Forensic radiology Postmortem computed tomography Diagnostic error Aortic dissection
1. Introduction At the beginning of the 21st century, post-mortem CT-scanning (PMCT) was introduced in several centers, particularly in US [1], Switzerland [2] and France [3]. PMCT has several advantages compared to traditional autopsy because this procedure is objective, rapid and storable for the future. In clinical studies, CT-angiography is considered the gold standard to diagnose aortic dissection. Nevertheless, the rate of false positive diagnosis of aortic dissection is reported to be 10% on CT-angiography [4]. First, occasionally normal anatomic structures may be misconstrued as being pathologic due to a lack of familiarity with anatomical variations [5,6]. False positive diagnoses can also result in cases where extra-aortic structures (e.g. aortic sinus, mediastinal veins, thickened pleura) are mistaken for false channels in the aorta [7] or when mediastinal tumors can be confused with dissection flaps [8]. Therefore, several conditions can lead to false positive diagnoses of aortic dissection by CT-scan even when CT-scan with a contrast medium is performed. Also when a PMCT is achieved, the fact that many artifacts due to blood elements sedimentation, intravascular clots and
* Corresponding author. Tel.: +33 2 32 88 82 84; fax: +33 2 32 88 86 76. E-mail address: [email protected] (I. Le Blanc-Louvry). http://dx.doi.org/10.1016/j.forsciint.2015.06.014 0379-0738/ß 2015 Published by Elsevier Ireland Ltd.
putrefaction are present, induces even more difficulties to interpret the vascular abnormalities, especially when non-contrast PMCT is carried out. Thus, as previously reported there is a difficulty in confirming the presence of an aortic dissection by PMCT [9]. In one case Kluschke et al. reported a case of a ruptured abdominal aortic aneurysm associated with ambiguous accessory findings on PMCT suggestive of thoracic aortic dissection, but not confirmed by autopsy: this pseudo-dissection was probably caused by sedimented and coagulated blood [10]. This report concerns two cases of false positive aortic dissection and illustrates potential errors as well as discusses their mechanisms. 2. Methods 2.1. Post-mortem CT-scanning Each corpse was wrapped in two artifact-free body bags. In both cases, the CT-scan allowed to completely explore the entire body including both the upper limbs and lower limbs. The examinations were performed on a sixty-four-detector CT scanner (Discovery 750HD, General Electric HealthCare1). The examination started with anterior-posterior and lateral scout views of the whole body including the head. Acquisition parameters for body scanning were: tube voltage 120 kVp, current
I. Le Blanc-Louvry et al. / Forensic Science International 254 (2015) e4–e6
intensity 200 mA, field of view 50 cm, slice thickness/increment 1.25 mm/1.25 mm. Images were then transferred to an ‘‘Advantage’’ (ADW, General Electric HealthCare1) work-station. A routine software (Reformat1) allowed multiplanar (conventional and oblique) reconstruction.
e5
Finally, among the 750 PMCT that to date were performed, four diagnoses of DeBakey type I aorta dissection were carried out, including only two that were confirmed by autopsy. When an aorta dissection was present, the images were identical to those obtained in the absence of dissection. Moreover, even after a second reading, no difference could be observed.
2.2. Autopsy Autopsies were routinely performed by two experienced forensic experts. Anatomical dissection was carried out according to European recommendations. 2.3. Radiological evaluation and data analysis PMCT was assessed by a radiologist who was aware of the circumstances of death. A second reading was performed by another radiologist who was blinded to the results of the previous radiological analysis. These radiologists have previously been involved in the reading of all the 750 cases performed in our hospital. 3. Cases 3.1. Case 1 PMCT was performed two days after death. On the axial and sagittal views through the thorax obtained in the corpse, an aspect of hyperdensity of the wall of the ascending aorta was observed (Fig. 1). However, during the autopsy, no dissection was observed, but a voluminous peri- and retroaortic abscess due to a parietal thoracic tumor that infiltrated the surrounding tissues. Moreover, after autopsy, when all the images were read again, a left axillary peripheral tissue infiltration was observed. 3.2. Case 2 On the axial images obtained three days after the death, an intramural hematoma appeared to be present in the wall of the ascending aorta (Fig. 2). Moreover, a fatty line seemed to separate the false lumen from the true lumen. Flap appearance in the ascending part of aorta also appeared to be present on sagittal images. However, the autopsy did not show any aortic dissection, but only a prevertebral cervical and thoracic hematoma due to several cervical vertebral fractures.
4. Discussion In this study we report two cases where PMCT findings were misinterpreted as an aortic dissection. The images mimiced an intramural hematoma similar to those found after DeBakey type I aortic dissections. These findings are interesting because it shows pit-falls in postmortem imaging that is essential to improve the quality of postmortem radiology in general. In fact, the lack of vascular contrast on non-contrast PMCTs and the presence of postmortem changes i.e. clotting or sedimentation, misinterpretation of PMCT findings are not rare [10]. If misdiagnosis of aortic dissection, secondary to motion artifact simulating an intimal flap in the ascending aorta, occurs in clinical practice [4,6–9], this type of mistake can in fact more frequently be found during post-mortem examination due to the lack of opacification and the presence of putrefaction artifacts such as clotting or sedimentation. Thus, often when the false lumen is not opacified, differentiation among a thrombus-filled atherosclerotic aneurysm, thrombosed dissection or intramural hematoma is difficult. As regards both of our reported cases, even though PMCT examinations were performed with a reliable multidetector CT (sixty-four-detector row scanner) that increases spatial and temporal resolution, nevertheless, without opacification, aortic dissection appeared to be present. In both cases, a cause was found to explain the erroneous diagnosis of dissection. In case 1, a main peri- and retro aortic abscess was highlighted. Therefore, false aortic dissection images were probably due to the presence of an inflammation of the surrounding tissues that induced a thickening of the aortic wall. In fact, periaortic fibrosis, but also mediastinal or pulmonary retroperitoneal tumors, can be mistaken for aorta dissection [8,11]. Similarly, in case 2, a prevertebral cervical and thoracic hematoma due to several cervical vertebral fractures may have led to a tissue modification that could have been confused with aorta dissection [8,11]. Then, on PMCT imaging, false positive diagnoses
Fig. 1. On these axial (A1) and sagittal (A2) images through the thorax obtained by PMCT in the corpse (case 1), an hyperdensity (arrow) of the wall of the ascending aorta mimics an aortic dissection. The autopsy found a voluminous peri- and retroaortic abscess due to a parietal thoracic tumor without dissection.
e6
I. Le Blanc-Louvry et al. / Forensic Science International 254 (2015) e4–e6
Fig. 2. On this axial image (A1), an intramural hematoma (single arrow) seems to be present in the wall of the ascending aorta (case 2). Moreover, a fatty line (double-arrow) seems separate a false lumen from a true lumen. Flap-like appearance in the ascending part of aorta (single arrow) is present on this sagittal image (A2). No dissection was found during autopsy but a prevertebral hematoma due to cervical vertebral skulls.
of aorta dissection were linked to artifacts created by pathologic tissues directly surrounding this vascular segment. Regarding one particular case, Schwendener et al. drew attention to the difficulty in affirming the presence of an aortic dissection by PMCT [9]. These authors explained that only a presumptive diagnosis of type II aortic dissection based on an anterior mediastinal enlargement could be performed. In addition, one report was related to a false positive diagnosis of thoracic aortic dissection associated with a true image of ruptured abdominal aortic aneurysm (confirmed by the autopsy), the pseudo-dissection being probably caused by sedimented and coagulated blood [10]. Finally, Ampanozi et al. reported that, in 76% (25/33) of their cases, signs which are indicative for aortic dissection (dislocated calcification, intimal-medial flap, double sedimentation level in true and false lumen) could be identified using a non-enhanced PMCT [12]. This suggests that specific training and education could be useful to improve the diagnostic accuracy based on this approach. Thus, in our experience, the false positive result may have been related to the limited experience of our radiologists in detecting aortic dissection on PMCT (2 aortic dissections/750 PMCT performed). Finally, due to the poor accuracy of PMTC to detect vascular abnormalities [1,13], opacification should be useful, even if the basic limit is the high costs of the equipment when the radiological examination is performed using a modified heart-lung machine [14]. An alternative would be to perform PMCT angiographies via a catheter inserted into the femoral artery using echography guidance. An article, regarding only one case, demonstrated the feasibility of this technique using a standard CT injector [15]. In conclusion, our cases illustrate some potential errors in detecting aorta dissection during PMCT. Misinterpretation can be avoid by the knowledge that abnormalities as an abscess or hematoma in the tissues around the aorta can mimic an aortic dissection, and also by a greater experience of the radiologists. Acknowledgement The authors are grateful to Richard Medeiros, Medical EditorRouen University Hospital, for editing the manuscript.
References [1] G. Levy, L. Goldstein, A. Blachar, S. Apter, E. Barenboim, Y. Bar-Dayan, A. Shamais, E. Atar, Postmortem computed tomography in victims of military air mishaps: radiological–pathological correlation of CT findings, Isr. Med. Assoc. J. 9 (2007) 699–702. [2] M.J. Thali, C. Jackowski, L. Oesterhelweg, S.G. Ross, R. Dirnhofer, VIRTOPSY—the Swiss virtual autopsy approach, Leg. Med. 9 (2007) 100–104. [3] I. Le Blanc-Louvry, S. Thureau, C. Duval, F. Papin-Lefebvre, J. Thiebot, J.N. Dacher, C. Gricourt, E. Toure´, B. Proust, Post-mortem computed tomography: compared to forensic autopsy findings—a French experience, Eur. Radiol. 23 (2013) 1829–1835. [4] C.E. Raymond, B. Aggarwal, P. Schoenhagen, D.M. Kralovic, K. Kormos, D. Holloway, V. Menon, Prevalence and factors associated with false positive suspicion of acute aortic syndrome: experience in a patient population transferred to a specialized aortic treatment center, Cardiovasc. Diagn. Ther. 3 (2013) 196–204. [5] M.A. McMahon, A. Squirrell, Multidetector CT of aortic dissection: a pictorial review, Radiographics 30 (2010) 445–450. [6] G. Shanmugam, J. McKeown, M. Bayfield, N. Hendel, C.C. Hughes, False positive computed tomography findings an aortic dissection, Heart Lung Circ. 13 (2004) 184–187. [7] J.D. Godwin, R.S. Breiman, J.M. Speckman, Problems and pitfalls in the evaluation of thoracic aortic dissection by computed tomography, J. Comput. Assit. Tomogr. 6 (1982) 750–776. [8] C. Sebastia, E. Pallisa, S. Quiroga, A. Alvarez-Castelis, R. Dominguez, A. Evandelista, Aortic dissection: diagnosis and follow up with helical CT, Radiographics 19 (1999) 45–50. [9] N. Schwendener, M. Mund, C. Jackowski, Type II DeBakey dissection with complete aortic rupture visualized by unenhanced postmortem imaging, Forensic Sci. Int. 225 (2013) 67–70. [10] F. Kluschke, S. Rosse, P.M. Flach, W. Schweitzer, G. Ampanozi, D. Gascho, B. Vonlanthen, M.J. Thali, T.D. Ruder, To see or not to see—ambiguous findings on post-mortem cross-sectional imaging in a case of ruptured abdominal aortic aneurysm, Leg. Med. 15 (2013) 256–259. [11] K.M. Nelsen, D.L. Spizarry, D.J. Kastan, Intimointimal intussusception in aortic dissection: ct diagnosis, Am. J. Roentgenol. 162 (1994) 813–814. [12] G. Ampanozi, P.M. Flach, J. Fornaro, S.G. Ross, W. Schweitzer, M.J. Thali, T.D. Ruder, Systematic analysis of the radiologic findings of aortic dissections on unenhanced postmortem computed tomography, Forensic Sci. Med. Pathol. 11 (2015) 162–167. [13] S.A. Bolliger, M.J. Thali, S. Ross, U. Buck, S. Naether, P.P. Vock, Postmortem imaging-guided biopsy as an adjuvant to minimally invasive autopsy with CT and postmortem angiography: a feasibility study, Am. J. Roentgenol. 195 (2010) 1051–1056. [14] S. Grabherr, F. Doenz, B. Steger, R. Dirnhoher, A. Dominguez, B. Sollberger, E. Gygax, E. Rizzo, C. Chevallier, R. Meuli, P. Mangin, Multi-phase post-mortem CT angiography: development of a standardized protocol, Int. J. Legal Med. 25 (2012) 791–802. [15] M. Jolibert, F. Cohen, C. Bartoli, C. Boval, V. Vidal, J.Y. Gaubert, G. Moulin, P. Petit, J.M. Bartoli, G. Leonetti, G. Gorincour, Postmortem CT-angiography: feasibility of US-guided vascular access, J. Radiol. 92 (2011) 446–449.