A pictorial review of normal anatomical appearences of Pericardial recesses on multislice Computed Tomography.

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1 A pictorial review of normal anatomical appearences of Pericardial recesses on multislice Computed Tomography. Poster No.: C-1787 Congress: ECR 2012 Type: Educational Exhibit Authors: N. Ahmed 1, G. Avery 2 ; 1 Hull/UK, 2 Cottingham, Ea/UK Keywords: Metastases, Normal variants, CT, Mediastinum, Cardiac, Anatomy DOI: /ecr2012/C-1787 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. Page 1 of 15

2 Learning objectives The main aim of this pictorial exhibit is to familiarise readers with the normal anatomical appearances of pericardial recesses on computed tomography (CT). Background Multidetector CT with narrow collimation enables acquisition and multiplanar reconstruction of high resolution volumetric data. In addition cardiac gating is also becoming more accessible. These advances enable improved delineation of cardiovascular anatomy. Pericardial recesses are thus routinely visualised and can be misinterpreted as a pathological process, most commonly as lymphadenopathy. This can have significant implications on diagnosis and management strategies, especially in the context of oncological imaging. Knowledge of normal anatomical appearances is essential for correct interpretation. Imaging findings OR Procedure details The visceral pericardium (epicardium) adheres to the heart and extends superiorly to cover great vessels. It forms recesses and sinuses, which can be visible at CT even in the absence of pericardial effusion. Pericardial recesses can be classified according to their origin from the pericardial cavity proper, transverse sinus or the oblique sinus [1]. 1)Pericardial cavity proper: The Right and Left pulmonary venous recesses are located along the lateral borders of the heart between the superior and inferior pulmonary veins (Fig 1,2). The post caval recess also arises from the pericardial cavity lying posterior to and the right of superior vena cava and it is usually quite small. 2)Transverse sinus: It is situated inferior and posterior to the aorta and pulmonary trunk (Fig 3). The superior extension of the transverse sinus is the superior aortic recess which extends anterior to the ascending aorta and has anterior, posterior and right lateral portions (Fig 4,5,6). The posterior extension of the superior aortic reecss can sometimes extend more cephalad and termed a high riding superior pericardial recess. This high riding variant can easily be confused with lymphadenopathy (Fig 7). The inferior aortic recess is a crescent shaped structure between the right lateral aspect of the ascending aorta and the right atrium. In addition the Right and Left Pulmonic recesses are the Page 2 of 15

3 lateral extension of the transverse sinus lying inferior to the right and left pulmonary arteries respectively (Fig 8,9). 3)Oblique sinus: The oblique sinus is located superior and posterior to the left superior pulmonary vein, being separated from the transverse sinus by a reflection of the pericardium (Fig 10, 11). Its extension behind the right pulmonary artery and medial to bronchus intermedius is called Posterior pericardial recess (Fig 12). Images for this section: Fig. 1: Right and Left pulmonary venous recesses. Page 3 of 15

4 Fig. 2: Coronal reformatted image demonstrating right and left pulmonary venous recesses. Page 4 of 15

5 Fig. 3: Sagittal reformatted image showing transverse sinus. Page 5 of 15

6 Fig. 4: Pericardial fluid is seen in both anterior and posterior extension of superior aortic recess. Page 6 of 15

7 Fig. 5: Posterior extension of superior aortic recess. Page 7 of 15

8 Fig. 6: Pericadial fluid in superior aortic recess mimicking a lymph node. Page 8 of 15

9 Fig. 7: High riding superior aortic (superior pericardial) recess. Page 9 of 15

10 Fig. 8: Right Pulmonic recess. Page 10 of 15

11 Fig. 9: Fluid in the left pulmonic recess (long arrow). Notice the difference in attenuation of fluid filled recess and lymph node (arrow head). Page 11 of 15

12 Fig. 10: Oblique sinus Page 12 of 15

13 Fig. 11: Coronal reformatted images demonstrating pericardial reflection separating the oblique and transverse sinus. Page 13 of 15

14 Fig. 12: Trace of fluid in the posterior pericardial recess. Page 14 of 15

15 Conclusion Pericardial recesses can be confidently differentiated from pathological processes on the basis of characteristic locations, relationship to the heart and great vessels and fluid attenuation. Familiarity with these appearances is important to avoid errors in radiological diagnosis. Personal Information References [1] Anatomic Pitfalls of the Heart and Pericardium. Lynn S. Broderic, Gregory N. Brooks, Janet E Kuhlman. RadioGraphics 2005; 25: Page 15 of 15