Total-body CT and MR features of postmortem change in in-hospital deaths

Abstract

Objectives: To evaluate the frequency of total-body CT and MR features of postmortem change in in-hospital deaths.

Materials and methods: In this prospective blinded cross-sectional study, in-hospital deceased adult patients underwent total-body postmortem CT and MR followed by image-guided biopsies. The presence of PMCT and PMMR features related to postmortem change was scored retrospectively and correlated with postmortem time interval, post-resuscitation status and intensive care unit (ICU) admittance.

Results: Intravascular air, pleural effusion, periportal edema, and distended intestines occurred more frequently in patients who were resuscitated compared to those who were not. Postmortem clotting was seen less often in resuscitated patients (p = 0.002). Distended intestines and loss of grey-white matter differentiation in the brain showed a significant correlation with postmortem time interval (p = 0.001, p<0.001). Hyperdense cerebral vessels, intravenous clotting, subcutaneous edema, fluid in the abdomen and internal livores of the liver were seen more in ICU patients. Longer postmortem time interval led to a significant increase in decomposition related changes (p = 0.026).

Conclusions: There is a wide variety of imaging features of postmortem change in in-hospital deaths. These imaging features vary among clinical conditions, increase with longer postmortem time interval and must be distinguished from pathologic changes.

Fig 1. Postmortem imaging features of the brain.

(A) PMCT: Symmetrical hyperdense cerebral arteries (arrowheads). (B) PMCT: Hyperdensity in the dependent cerebral veins and sagittal sinus (arrowheads). (C) T1w PMMR: High signal of the basal nuclei of the brain (arrowheads). (D) T1w PMMR: Sulcal effacement (arrowheads). (E/F) PMCT (E) and antemortem CT (F) of the same patient. The antemortem CT scan shows normal grey-white matter differentiation (arrowhead). PMCT shows complete loss of grey-white matter differentiation (arrowhead).

Fig 2. Postmortem imaging features of the heart and large vessels.

(A) T2w PMMR: Sedimentation of blood in the heart chambers (arrowhead). T2 signal decay from subepicardial to subendocardial myocardium (arrows). (B) T2w PMMR: Postmortem clotting in the right atrium (arrowhead). Additional finding: a mediastinal herniation of the stomach (asterisk). (C/D) PMCT: Extensive air in the right and left ventricle (arrowheads) and coronary veins (arrows). (E) PMCT: Collapsed ascending aorta (arrowhead). (F) T2w PMMR: Sedimentation of the blood (arrowheads), the plasma layer becomes hyperintense and the dependent layer becomes hypointense. (G) PMCT: Relatively hyperdense aortic wall (arrow) as a result of sedimentation. This is best seen in the ascending aorta. The descending aorta shows a sedimentation level with a hyperdense aspect of the anterior vessel wall (arrowhead). (H) PMCT: Complete collapse of the abdominal aorta (arrowhead) and vena cava inferior (arrow).

Fig 3. Internal livores of the lungs versus pneumonia.

(A/C) antemortem CT (A) and PMCT (C). Normal (A) and internal livores (C) (arrowheads). (B/D) antemortem CT (B) and PMCT (D). Patient with a pneumonia (arrowheads). (E) CT-guided lung biopsies in the same patient as A/C. (F) CT-guided lung biopsy in the same patient as B/D. (G) HE, x100 original magnification. Lung parenchyma non-dependent: capillaries in alveolar walls practically devoid of blood (arrowhead). (H) HE, x100 original magnification. Same patient as G, lung parenchyma dependent, capillaries in alveolar walls congested with blood (arrowhead). (I) HE, x100 original magnification. Same patient as B/D/F, lung parenchyma, resolving pneumonia with thickened alveolar walls with mainly lymphocytic infiltrates, and hyaline membranes and extravasations of erythrocytes in the alveolar spaces.

Fig 4. Internal livores of the liver and spleen.

(A/C) T1w (A) and T2w fs (C) PMMR. Internal livores. In the liver 3 distinct layers (arrowheads) of different T1 signal can be seen and in the spleen 2 layers (arrows). A low T1 signal layer on top, relatively intermediate-to high signal layer in the middle and a low T1 signal layer in the dependent part of the liver. On T2w fs internal livores are not clearly seen. (B/D) T1w (B) and T2w fs (D) PMMR. The spleen shows 2 layers of different T2 signal (arrowheads). T1w show no clear livores in this patient. (E) HE, x100 original magnification. Centrilobular area of the liver with wide sinuses extended by blood (asterisks). (F) HE, x200 original magnification. Congested spleen with lakes of blood (asterisks).

Fig 5. Postmortem imaging features of the abdomen.

(A) T2w PMMR: Periportal edema (arrowhead) and subcutaneous edema (asterisks). (B) PMCT: Putrefactive gas in the liver vessels (arrowhead) and distended stomach (asterisk). (C/ D) PMCT: Gas in the intestinal wall (arrowhead) and air in the mesenteric and portal veins (arrows). (E) T2w PMMR: Subcutaneous edema (asterisks) and fluid in the abdomen (arrowhead). (F) PMCT: Distended intestines with a sharp fluid-air level (arrowhead).

Fig 6. Pulmonary thrombo-embolism versus postmortem blood clot.

(A/C/E) Antemortem CT (A) and T2w (C) and T1w (E) PMMR in the same patient. Antemortem CT (A) shows no abnormalities in the pulmonary arteries. PMMR (C/E) shows an irregularly shaped clot in the right pulmonary artery (C: arrowhead), with low T1 signal (E: arrowhead). (B/D/F) Antemortem CTA (B) and T2w (D) and T1w (F) PMMR in a patient with a thrombo-embolus. Antemortem CTA (B) shows a thrombo-embolus in the right and left pulmonary artery (arrowheads). PMMR (D/F) shows a thrombo-embolus in the right pulmonary artery (arrowheads). (G) HE, x16 original magnification, corresponding to image A/C/E. Wall of right pulmonary artery with a postmortem blood clot (asterisk). (I) HE, x50 original magnification, corresponding to image A/C/E. Higher power of blood clot showing blood with loosely arranged depositions of fibrin. (H) HE, x16 original magnification, corresponding to image B/D/F. Wall of pulmonary artery and thrombus. (J) HE, x50 original magnification, corresponding to image B/D/F. Wall of pulmonary artery and thrombus with dense depositions of fibrin and platelets, alternating with degenerated erythrocytes and white blood cells, thus constituting so-called lines of Zahn.