Postmortem Computed Tomography Finding of Lungs in Sudden Infant Death.

Postmortem Computed Tomography Finding of Lungs in Sudden Infant Death. Poster No.: C-1147 Congress: ECR 2013 Type: Educational Exhibit Authors: Y. Kawasumi, A. Usui, Y. Hosokai, M. Sato, A. Nakajima, K. Abiko, Y. Takane, Y. Hayashizaki, M. Funayama; Sendai/JP Keywords: Forensic / Necropsy studies, Lung, CT, Diagnostic procedure, Forensics DOI: 10.1594/ecr2013/C-1147 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 15

Learning objectives To present the post-mortem CT findings of lungs in sudden infant death and the correlations with autopsy results. Background The use of post-mortem computed tomography (CT) in forensic medicine is growing [1-3]. Many differences between post-mortem and clinical CT findings exist. Therefore, radiologists must gain experience in interpretation of post-mortem CT images. Sudden infant death frequently shows characteristic pulmonary findings that differ from those of adult death. The pulmonary findings are common post-mortem changes in infants, but are occasionally obscured by airway diseases such as bronchitis, bronchiolitis, and pneumonia. We here report various pulmonary findings in cases of sudden infant death. Imaging findings OR Procedure details CT Technique CT: Aquilion 8 MDCT, Toshiba, Japan. Scanning protocol: # HEAD -Tube Voltage: 120 kvp -Tube Current: Arbitrary -Rotation Time: 1.5 s -Collimation: 4.0 mm, 8.0 mm (four-stacks) -Beam Pitch: Non-helical -Table Speed: Non-helical Page 2 of 15

# BODY -Tube Voltage: 120 kvp -Tube Current: Arbitrary -Rotation Time: 0.75 s -Collimation: 2.0 mm -Beam Pitch: 0.875 -Table Speed: 14 mm/rot All cases underwent a conventional autopsy soon after CT examination. After the forensic pathology autopsy reports were received, the CT images were reviewed. The correlations between the CT findings and autopsy results are discussed. Findings (1) Sudden infant death of unknown cause. The causes of sudden infant death are unknown in many cases, even at autopsy. In such cases, the lungs show nearly complete atelectasis or negligible air on post-mortem CT. Figures 1 to 3 show sudden infant death cases of unknown causes. In the CT images, the lungs in all cases are described as showing extensive atelectasis [Fig. 1a, 2, 3]. No air is found in the trachea or bronchi. At autopsy, the lungs are reduced and seem congested macroscopically [Fig. 1b]. Microscopically, the alveoli retain little air and are collapsed [Fig. 1c]. There is no inflammatory cell infiltration. Page 3 of 15

Fig. 1: A case of sudden infant death of unknown cause. (a) CT of the lungs shows atelectasis in most lung fields, with little air in the left lung. (b) Macroscopically, the lungs are reduced and seem congested. (c) Microscopically, the alveoli retain little air and are collapsed; there is no inflammatory cell infiltration. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP Page 4 of 15

Fig. 2: CT images of a case of sudden infant death of unknown cause show atelectasis in most lung fields. A small amount of air is seen in the lungs bilaterally. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP Page 5 of 15

Fig. 3: CT images of a case of sudden infant death of unknown cause show atelectasis in most lung fields. Only the right middle lobe has an aerated lung field. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP In occasional sudden infant death cases of unknown causes, atelectasis is obscure. However, even these cases have diffuse ground-glass opacity and a small proportion of normally aerated lung field [Fig. 4]. Page 6 of 15

Fig. 4: CT images of a case of sudden infant death of unknown cause show (a) no atelectasis in the lung, although diffuse ground-glass opacity is found throughout the lung field and normal aerated lung field is not evident. (b) Microscopically, there is no inflammation, but some haemorrhage within the alveoli. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP (2) Sudden infant death with airway disease. In contrast, cases in which the causes of death are associated with airway lesions, such as pneumonia and bronchitis proven at autopsy, retain greater amounts of air in their lungs. Figure 5 shows a CT image of a case of bronchopneumonia and Figure 6 a case of pneumonia. Heterogeneous consolidation and ground-glass opacity in the lungs are evident. A relatively large aerated lung field area is also observed. Microscopically, the lungs contain aerated and dilated alveoli intermingled with atelectasis [Fig. 6b]. The atelectasis includes congestion, haemorrhage, and inflammatory cell infiltration. Page 7 of 15

Fig. 5: CT images of a case of sudden infant death with bronchopneumonia show consolidation and ground-glass opacity distributed heterogeneously in the lungs. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP Page 8 of 15

Fig. 6: CT images of a case of sudden infant death with pneumonia show (a) heterogeneous consolidation and ground-glass opacity in the lungs. (b) Microscopically, aerated, dilated alveoli and atelectasis are observed. The atelectasis includes congestion, haemorrhage, and marked inflammatory cell infiltration. References: Clinical Imaging, Tohoku University Graduate School of Medicine Sendai/JP Images for this section: Fig. 1: A case of sudden infant death of unknown cause. (a) CT of the lungs shows atelectasis in most lung fields, with little air in the left lung. (b) Macroscopically, the lungs Page 9 of 15

are reduced and seem congested. (c) Microscopically, the alveoli retain little air and are collapsed; there is no inflammatory cell infiltration. Fig. 2: CT images of a case of sudden infant death of unknown cause show atelectasis in most lung fields. A small amount of air is seen in the lungs bilaterally. Page 10 of 15

Fig. 3: CT images of a case of sudden infant death of unknown cause show atelectasis in most lung fields. Only the right middle lobe has an aerated lung field. Page 11 of 15

Fig. 4: CT images of a case of sudden infant death of unknown cause show (a) no atelectasis in the lung, although diffuse ground-glass opacity is found throughout the lung field and normal aerated lung field is not evident. (b) Microscopically, there is no inflammation, but some haemorrhage within the alveoli. Page 12 of 15

Fig. 5: CT images of a case of sudden infant death with bronchopneumonia show consolidation and ground-glass opacity distributed heterogeneously in the lungs. Page 13 of 15

Fig. 6: CT images of a case of sudden infant death with pneumonia show (a) heterogeneous consolidation and ground-glass opacity in the lungs. (b) Microscopically, aerated, dilated alveoli and atelectasis are observed. The atelectasis includes congestion, haemorrhage, and marked inflammatory cell infiltration. Page 14 of 15

Conclusion Radiologists should be aware that the atelectatic lung is a common CT finding in sudden infant death. In contrast, in cases in which the lungs retain relatively large amounts of air, the respiratory passage might contain lesions. Acknowledgements: I thank Prof. Ishibashi and Prof. Saito, who aided in implementing the post-mortem CT examinations. References 1. Dirnhofer R, Fackowski C, Vock P et al. VIRTOPSY: Minimally Invasive, Imagingguided Virtual Autopsy. RadioGraphics 2006;26:1305-1333 2. Thali MJ, Jackowski C, Oesterhelweg L et al. Virtopsy - the Swiss virtual autopsy approach. Leg Med 2007;9(2):100-104 3. Bolliger SA, Thali MJ, Ross S et al. Virtual autopsy using imaging: bridging radiologic and forensic sciences. A review of the Virtopsy and similar projects. Eur Radiol 2008;18:273-282 Personal Information Yusuke KAWASUMI, M.D., Ph.D. Tohoku University Graduate School of Medicine Course of Radiological Technology Clinical Imaging Page 15 of 15