IMAGES IN PULMONARY, CRITICAL CARE, SLEEP MEDICINE AND THE SCIENCES Discrepancy between Dual-Energy Computed Tomography Lung Perfusion Blood Volume and Lung Perfusion Single-Photon Emission Computed Tomography/Computed Tomography Images in Pulmonary Embolism Hirofumi Koike1, Eijun Sueyoshi1, Hiroki Nagayama1, Kazuto Ashizawa1, Ichiro Sakamoto1, Masataka Uetani1, Takashi Kudo2, and Satoshi Ikeda3 1 Department of Radiology and 3Department of Cardiology, Nagasaki University School of Medicine, Nagasaki, Japan; and 2Department of Radioisotope Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
A 24-year-old male with antiphospholipid syndrome (APS) had taken warfarin for 2 years. Two months ago, after he had stopped taking warfarin, he presented with acute dyspnea. He was admitted to our hospital for evaluation and treatment. At admission, contrast-enhanced computed tomography (CT) image (Somatom Definition; Siemens Healthcare, Erlangen, Germany) showed occlusive embolism in segmental-subsegmental arteries of right segment 5 (S5) and lower lobe (Figure 1A, arrows). Lung perfusion blood volume (PBV) images showed a perfusion defect only in right S5, corresponding to occlusive pulmonary embolism. However, perfusion defect was not found in the right lower lobe (Figure 1B). The dilated bronchial artery suggested that a systemic collateral supply had developed (Figure 1C, arrows). Lung perfusion single-photon emission computed tomography (SPECT)/CT images showed that perfusion defects were found in the right S5 and lower lobe (Figure 1D, arrows). A previous report showed that perfusion defects on acute pulmonary embolism corresponded to lung PBV and lung perfusion SPECT (1). Usually, perfusion defects in chronic thromboembolic pulmonary hypertension also correspond to lung PBV and lung perfusion SPECT (2). However, in some cases, there is a discrepancy between them because of the systemic collateral supply (3, 4). Lung perfusion SPECT depicts only pulmonary artery perfusion, but lung PBV depicts both pulmonary artery perfusion and systemic collateral supply. In our case, the discrepancy between lung PVB and lung perfusion SPECT images might have been caused by the presence of systemic collateral supply via dilated bronchial artery. n Author disclosures are available with the text of this article at www.atsjournals.org.
References 1. Thieme SF, Becker CR, Hacker M, Nikolaou K, Reiser MF, Johnson TR. Dual energy CT for the assessment of lung perfusion—correlation to scintigraphy. Eur J Radiol 2008;68:369–374. 2. Nakazawa T, Watanabe Y, Hori Y, Kiso K, Higashi M, Itoh T, Naito H. Lung perfused blood volume images with dual-energy computed tomography for chronic thromboembolic pulmonary hypertension: correlation to scintigraphy with single-photon emission computed tomography. J Comput Assist Tomogr 2011;35:590–595.
3. Renard B, Remy-Jardin M, Santangelo T, Faivre JB, Tacelli N, Remy J, Duhamel A. Dual-energy CT angiography of chronic thromboembolic disease: can it help recognize links between the severity of pulmonary arterial obstruction and perfusion defects? Eur J Radiol 2011;79: 467–472. 4. Thieme SF, Graute V, Nikolaou K, Maxien D, Reiser MF, Hacker M, Johnson TR. Dual energy CT lung perfusion imaging—correlation with SPECT/CT. Eur J Radiol 2012;81:360–365.
Am J Respir Crit Care Med Vol 189, Iss 12, pp e71–e72, Jun 15, 2014 Copyright © 2014 by the American Thoracic Society DOI: 10.1164/rccm.201306-1139IM Internet address: www.atsjournals.org
Images in Pulmonary, Critical Care, Sleep Medicine and the Sciences
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Figure 1.
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American Journal of Respiratory and Critical Care Medicine Volume 189 Number 12 | June 15 2014
A 24-year-old male with antiphospholipid syndrome (APS) had taken warfarin for 2 years. Two months ago, after he had stopped taking warfarin, he presented with acute dyspnea. He was admitted to our hospital for evaluation and treatment. At admission, contrast-enhanced computed tomography (CT) image (Somatom Definition; Siemens Healthcare, Erlangen, Germany) showed occlusive embolism in segmental-subsegmental arteries of right segment 5 (S5) and lower lobe (Figure 1A, arrows). Lung perfusion blood volume (PBV) images showed a perfusion defect only in right S5, corresponding to occlusive pulmonary embolism. However, perfusion defect was not found in the right lower lobe (Figure 1B). The dilated bronchial artery suggested that a systemic collateral supply had developed (Figure 1C, arrows). Lung perfusion single-photon emission computed tomography (SPECT)/CT images showed that perfusion defects were found in the right S5 and lower lobe (Figure 1D, arrows). A previous report showed that perfusion defects on acute pulmonary embolism corresponded to lung PBV and lung perfusion SPECT (1). Usually, perfusion defects in chronic thromboembolic pulmonary hypertension also correspond to lung PBV and lung perfusion SPECT (2). However, in some cases, there is a discrepancy between them because of the systemic collateral supply (3, 4). Lung perfusion SPECT depicts only pulmonary artery perfusion, but lung PBV depicts both pulmonary artery perfusion and systemic collateral supply. In our case, the discrepancy between lung PVB and lung perfusion SPECT images might have been caused by the presence of systemic collateral supply via dilated bronchial artery. n Author disclosures are available with the text of this article at www.atsjournals.org.
References 1. Thieme SF, Becker CR, Hacker M, Nikolaou K, Reiser MF, Johnson TR. Dual energy CT for the assessment of lung perfusion—correlation to scintigraphy. Eur J Radiol 2008;68:369–374. 2. Nakazawa T, Watanabe Y, Hori Y, Kiso K, Higashi M, Itoh T, Naito H. Lung perfused blood volume images with dual-energy computed tomography for chronic thromboembolic pulmonary hypertension: correlation to scintigraphy with single-photon emission computed tomography. J Comput Assist Tomogr 2011;35:590–595.
3. Renard B, Remy-Jardin M, Santangelo T, Faivre JB, Tacelli N, Remy J, Duhamel A. Dual-energy CT angiography of chronic thromboembolic disease: can it help recognize links between the severity of pulmonary arterial obstruction and perfusion defects? Eur J Radiol 2011;79: 467–472. 4. Thieme SF, Graute V, Nikolaou K, Maxien D, Reiser MF, Hacker M, Johnson TR. Dual energy CT lung perfusion imaging—correlation with SPECT/CT. Eur J Radiol 2012;81:360–365.
Am J Respir Crit Care Med Vol 189, Iss 12, pp e71–e72, Jun 15, 2014 Copyright © 2014 by the American Thoracic Society DOI: 10.1164/rccm.201306-1139IM Internet address: www.atsjournals.org
Images in Pulmonary, Critical Care, Sleep Medicine and the Sciences
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IMAGES IN PULMONARY, CRITICAL CARE, SLEEP MEDICINE AND THE SCIENCES
Figure 1.
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