(Radiology. 1999;212:69-73.)
© RSNA, 1999
Pericardial Sinuses and Recesses: Findings at Electrocardiographically Triggered Electron-Beam CT1
Reinhard Groell, MD,
Gottfried J. Schaffler, MD and
Rainer Rienmueller, MD
1 From the Department of Radiology, University Hospital Graz, Auenbruggerplatz 9, A-8036 Graz, Austria. Received April 14, 1998; revision requested May 29; final revision received October 30; accepted February 12, 1999. Address reprint requests to R.G.
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Abstract
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PURPOSE: To evaluate the appearance of the pericardial sinuses and recesses at electrocardiographically triggered electron-beam computed tomography (CT).
MATERIALS AND METHODS: Findings in 100 patients without known pericardial disease were reviewed. The patients underwent electron-beam CT of the heart because of suspected coronary arterial disease. Incremental electrocardiographically triggered images were obtained with a 100-msec exposure time and 1.5-mm section thickness after intravenous administration of contrast material. The appearance of the pericardial sinuses and recesses was determined.
RESULTS: In each patient, at least one of the sinuses was visible at CT. The transverse and oblique sinuses (or one of their recesses) were depicted in 95 and 89 patients, respectively. The left pulmonic recess was depicted in 81 patients; inferior aortic recess, 80 patients; posterior pericardial recess, 67 patients; left pulmonic vein recess, 60 patients; right pulmonic recess, 51 patients; superior aortic recess, 47 patients; right pulmonic vein recess, 29 patients; and postcaval recess, 23 patients.
CONCLUSION: Pericardial sinuses and recesses are frequently depicted on electrocardiographically triggered electron-beam CT images. Knowledge of their locations is helpful in the differentiation of normal pericardium from pericardial effusions and mediastinal processes such as lymph nodes.
Index terms: Computed tomography (CT), electron beam, 51.12112, 51.12114, 51.12118, 55.12112, 55.12114, 55.12118 • Heart, anatomy, 51.92 • Heart, CT, 51.12112, 51.12114, 55.12112, 55.12114 • Pericardium • Pericardium, CT, 55.12112, 55.12114, 55.12118, 55.92
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Introduction
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In their cross-sectional anatomic study, Vesely and Cahill (1) systematically described and named the pericardial recesses. In former computed tomographic (CT) studies (2–7), some of these recesses were identified with different frequencies as areas of water attenuation around the great mediastinal vessels. The knowledge of their location and appearance was considered to be helpful to the radiologist in avoiding the misdiagnosis of lymphadenopathy and other mediastinal disease processes. With the advent of fast imaging modalities that provide high temporal and spatial resolution, more and more recesses have been observed on imaging studies of the mediastinum. Although in most of the reports, the appearance of the cranial (superior aortic and left pulmonic) recesses was described, less is known about the caudal (inferior aortic, postcaval, and pulmonary vein) recesses. In our experience, some of these recesses, particularly the less well-known ones, have caused diagnostic problems in the evaluation of cardiac and pericardiac structures. This led us to review 100 consecutive thin-section, electrocardiographically triggered electron-beam CT images obtained in patients who had no known pericardial disease to evaluate the appearance of the pericardial sinuses and recesses.
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MATERIALS AND METHODS
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We reviewed 100 consecutive electron-beam CT images obtained in patients (56 men, 44 women; mean age ± SD, 52 years ± 11; age range, 27–88 years) who did not have clinical evidence of pericardial effusion, pericarditis, or mediastinal lymphadenopathy. The patients had been examined between November 1996 and December 1997 because they were clinically suspected of having coronary arterial disease. CT was performed with an electron-beam CT scanner (Evolution; Siemens, Erlangen, Germany). All patients were lying in the supine position, and the images were obtained in the middle of inspiration; in our experience, this enables patients to maintain a maximal breath hold. Forty to 60 contiguous, axial sections were obtained by using a collimation of 1.5 mm and exposure time of 100 msec. The images were cardiac gated at the end of diastole (at 80% of the RR interval) to minimize cardiac motion artifacts. Nonionic contrast material (120 mL of iopromide [Ultravist 300; Schering, Berlin, Germany]) was injected into an antecubital vein at a rate of 3 mL/sec. The scanning delay in each patient was individually determined after the administration of a test bolus of 10 mL of contrast material. Typically, the scanning delay range was 20–25 seconds. Because the examinations were performed to image the proximal 4–5 cm of the coronary arteries, the imaging extended from the top of the right pulmonary artery to the bottom of the left atrium (6–9 cm in the craniocaudal direction, depending on the heart size).
The nomenclature of the pericardial cavity, based on the Nomina Anatomica and work of Vesely and Cahill (1), is described in the Key Box. Three recesses of the pericardial cavity proper were named as follows: postcaval recess, left pulmonic vein recess, and right pulmonic vein recess. The transverse sinus was divided into the following four recesses: the superior aortic recess, inferior aortic recess, left pulmonic recess, and right pulmonic recess. In addition, we added the following subdivisions to the descriptions of the sinuses and recesses that had been suggested previously by Kubota et al (2): The superior aortic recess was divided into the anterior, posterior, and right lateral portions. The posterior pericardial recess was described as part of the oblique sinus.
To distinguish pericardial sinuses and recesses from lymphatic tissue or soft tissue, we, like others before us, used the criterion of sharply outlined structures with uniform water-equivalent attenuation without walls or rims in the expected anatomic locations to define sinuses and recesses (3). To evaluate the frequency of the depiction of the sinuses and recesses, all images were reviewed by two radiologists (R.G., G.J.S.) in a consensus reading.
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RESULTS
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All 100 electron-beam CT images were included in the evaluation, because there were no limiting factors that might reduce image quality such as beam-hardening or motion artifacts. The pericardium had the appearance of a thin band in the anterior mediastinum (Fig 1).
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Figure 1. Electron-beam CT image of the mediastinum. The pericardium appears as a thin band (arrows) in the anterior mediastinum.
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In each patient, at least one of the sinuses or recesses could be identified. Figures 2–4 are drawings of the sinuses and recesses and the corresponding CT images. Note that all of the CT images were obtained in different patients. The transverse sinus or one of its recesses was depicted in 95 patients, and the oblique sinus, including the posterior pericardial recess, was depicted in 89 patients. The pericardial recesses were depicted as follows: the left pulmonic recess was demonstrated in 81 patients; inferior aortic recess, in 80 patients; posterior pericardial recess, in 67 patients; left pulmonic vein recess, in 60 patients; right pulmonic recess, in 51 patients; superior aortic recess, in 47 patients; right pulmonic vein recess, in 29 patients; and postcaval recess, in 23 patients.
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Figure 2a. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–d) corresponding electron-beam CT images (obtained in different patients) at the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The pericardium (short white arrow) is seen in the anterior mediastinum. (b–d) The left pulmonic recess (straight white arrow) lies lateral to the main pulmonary artery. The posterior pericardial recess (curved arrow) of the oblique sinus is posterior to the right pulmonary artery and medial to the bronchus. The anterior portion of the superior aortic recess, right lateral portion of the superior aortic recess, and posterior portion of the superior aortic recess (black arrows) also are seen.
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Figure 2b. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–d) corresponding electron-beam CT images (obtained in different patients) at the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The pericardium (short white arrow) is seen in the anterior mediastinum. (b–d) The left pulmonic recess (straight white arrow) lies lateral to the main pulmonary artery. The posterior pericardial recess (curved arrow) of the oblique sinus is posterior to the right pulmonary artery and medial to the bronchus. The anterior portion of the superior aortic recess, right lateral portion of the superior aortic recess, and posterior portion of the superior aortic recess (black arrows) also are seen.
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Figure 2c. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–d) corresponding electron-beam CT images (obtained in different patients) at the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The pericardium (short white arrow) is seen in the anterior mediastinum. (b–d) The left pulmonic recess (straight white arrow) lies lateral to the main pulmonary artery. The posterior pericardial recess (curved arrow) of the oblique sinus is posterior to the right pulmonary artery and medial to the bronchus. The anterior portion of the superior aortic recess, right lateral portion of the superior aortic recess, and posterior portion of the superior aortic recess (black arrows) also are seen.
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Figure 2d. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–d) corresponding electron-beam CT images (obtained in different patients) at the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The pericardium (short white arrow) is seen in the anterior mediastinum. (b–d) The left pulmonic recess (straight white arrow) lies lateral to the main pulmonary artery. The posterior pericardial recess (curved arrow) of the oblique sinus is posterior to the right pulmonary artery and medial to the bronchus. The anterior portion of the superior aortic recess, right lateral portion of the superior aortic recess, and posterior portion of the superior aortic recess (black arrows) also are seen.
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Figure 3a. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b, c) corresponding electron-beam CT images (obtained in different patients) below the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RAA = right atrial appendage, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The oblique sinus (curved white arrow) is posterior to the right pulmonary artery and left atrium. The postcaval recess (straight black arrow) may be seen at the same level lateral and posterior to the superior vena cava. (b, c) The transverse sinus (curved black arrow) lies posterior to the ascending aorta. (c) The right pulmonic recess (open arrow) extends posteriorly below the right pulmonary artery.
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Figure 3b. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b, c) corresponding electron-beam CT images (obtained in different patients) below the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RAA = right atrial appendage, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The oblique sinus (curved white arrow) is posterior to the right pulmonary artery and left atrium. The postcaval recess (straight black arrow) may be seen at the same level lateral and posterior to the superior vena cava. (b, c) The transverse sinus (curved black arrow) lies posterior to the ascending aorta. (c) The right pulmonic recess (open arrow) extends posteriorly below the right pulmonary artery.
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Figure 3c. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b, c) corresponding electron-beam CT images (obtained in different patients) below the level of the right pulmonary artery (RPA). In a, AA = ascending aorta, B = bronchus intermedius, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, MPA = main pulmonary artery, RAA = right atrial appendage, RSPV = right superior pulmonary vein, SVC = superior vena cava. (See Key Box for abbreviation expansions not given here.) (b) The oblique sinus (curved white arrow) is posterior to the right pulmonary artery and left atrium. The postcaval recess (straight black arrow) may be seen at the same level lateral and posterior to the superior vena cava. (b, c) The transverse sinus (curved black arrow) lies posterior to the ascending aorta. (c) The right pulmonic recess (open arrow) extends posteriorly below the right pulmonary artery.
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Figure 4a. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–e) corresponding electron-beam CT images (obtained in different patients) at the level of the left atrium (LA). In a, AA = ascending aorta, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, RA = right atrium, RAA = right atrial appendage, RSPV = right superior pulmonary vein, RVAT = right ventricular outflow tract. (See Key Box for abbreviation expansions not given here.) (b–d) The inferior aortic recess (straight black arrow in b and c) extends downward behind the ascending aorta. The superior aortic recess (short arrow in c) also is seen. The left pulmonic vein recess (straight white arrow) is between the left pulmonic veins. The oblique sinus (curved arrow in b and d) lies posterior to the left atrium. (e) The right pulmonic vein recess (arrow) is adjacent to the right pulmonic veins.
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Figure 4b. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–e) corresponding electron-beam CT images (obtained in different patients) at the level of the left atrium (LA). In a, AA = ascending aorta, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, RA = right atrium, RAA = right atrial appendage, RSPV = right superior pulmonary vein, RVAT = right ventricular outflow tract. (See Key Box for abbreviation expansions not given here.) (b–d) The inferior aortic recess (straight black arrow in b and c) extends downward behind the ascending aorta. The superior aortic recess (short arrow in c) also is seen. The left pulmonic vein recess (straight white arrow) is between the left pulmonic veins. The oblique sinus (curved arrow in b and d) lies posterior to the left atrium. (e) The right pulmonic vein recess (arrow) is adjacent to the right pulmonic veins.
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Figure 4c. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–e) corresponding electron-beam CT images (obtained in different patients) at the level of the left atrium (LA). In a, AA = ascending aorta, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, RA = right atrium, RAA = right atrial appendage, RSPV = right superior pulmonary vein, RVAT = right ventricular outflow tract. (See Key Box for abbreviation expansions not given here.) (b–d) The inferior aortic recess (straight black arrow in b and c) extends downward behind the ascending aorta. The superior aortic recess (short arrow in c) also is seen. The left pulmonic vein recess (straight white arrow) is between the left pulmonic veins. The oblique sinus (curved arrow in b and d) lies posterior to the left atrium. (e) The right pulmonic vein recess (arrow) is adjacent to the right pulmonic veins.
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Figure 4d. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–e) corresponding electron-beam CT images (obtained in different patients) at the level of the left atrium (LA). In a, AA = ascending aorta, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, RA = right atrium, RAA = right atrial appendage, RSPV = right superior pulmonary vein, RVAT = right ventricular outflow tract. (See Key Box for abbreviation expansions not given here.) (b–d) The inferior aortic recess (straight black arrow in b and c) extends downward behind the ascending aorta. The superior aortic recess (short arrow in c) also is seen. The left pulmonic vein recess (straight white arrow) is between the left pulmonic veins. The oblique sinus (curved arrow in b and d) lies posterior to the left atrium. (e) The right pulmonic vein recess (arrow) is adjacent to the right pulmonic veins.
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Figure 4e. (a) Cross-sectional drawing of the pericardial sinuses and recesses and (b–e) corresponding electron-beam CT images (obtained in different patients) at the level of the left atrium (LA). In a, AA = ascending aorta, DA = descending aorta, E = esophagus, LAA = left atrial appendage, LSPV = left superior pulmonary vein, RA = right atrium, RAA = right atrial appendage, RSPV = right superior pulmonary vein, RVAT = right ventricular outflow tract. (See Key Box for abbreviation expansions not given here.) (b–d) The inferior aortic recess (straight black arrow in b and c) extends downward behind the ascending aorta. The superior aortic recess (short arrow in c) also is seen. The left pulmonic vein recess (straight white arrow) is between the left pulmonic veins. The oblique sinus (curved arrow in b and d) lies posterior to the left atrium. (e) The right pulmonic vein recess (arrow) is adjacent to the right pulmonic veins.
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DISCUSSION
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The pericardium consists of an outer fibrous layer (the fibrous pericardium) and an inner serous sac (the serous pericardium) (8). The serous pericardium consists of an inner visceral layer (the epicardium), which is intimately connected to the heart and the epicardial fat, and an outer parietal layer, which lines the fibrous pericardium. The visceral layer is reflected from the heart and the root of the great vessels onto the inner surface of the fibrous pericardium to become continuous with the parietal layer. The pericardial cavity lies between these two layers of the serous pericardium. Under physiologic conditions, it contains 20-25 mL of serous fluid; however, the amount of fluid may vary considerably among individuals, particularly in children and infants (9). These differences may explain, at least in part, why in some patients, sinuses or recesses may or may not be seen. Moreover, clinically asymptomatic patients can have large pericardial fluid collections, especially when it accumulates over long periods, and it may be found incidentally.
At the reflections of the serous pericardium between the great vessels at the base of the heart, the pericardial cavity forms the pericardial sinuses, which are not separate compartments, but rather they represent extensions of the pericardial cavity. The Nomina Anatomica labels them the transverse sinus and oblique sinus. As the pericardium extends onto the roots of the great vessels, the pericardial cavity proper and the sinuses form recesses, as described by Vesely and Cahill (1). Because there is no histologic difference between the layers of the sinuses and those of the recesses, their differentiation is based on topographic landmarks (1).
Recesses of the Pericardial Cavity Proper
The postcaval recess (Fig 3) is an extension of the pericardial cavity proper that lies behind and on the right lateral aspect of the superior vena cava. The right and left pulmonic vein recesses (Fig 4) are between the superior and inferior pulmonic veins on both sides. In our series, these three recesses of the pericardial cavity proper were usually small, with diameters of up to approximately 1 cm. The left pulmonic vein recess was depicted at CT more often (in 60 [60%] of 100 patients) than was the right pulmonic vein recess and postcaval recess, which were depicted in 29% and 23% of patients, respectively. These recesses are located in the venous reflection zone of the pericardium where the pericardium is attached to the adventitia of the superior vena cava and the pulmonary veins, with no fat tissue between these structures. Vesely and Cahill (1) demonstrated the close relationship between the bronchopulmonary lymph nodes and these recesses.
Transverse Sinus
The transverse sinus (Fig 3) is posterior to the ascending aorta and pulmonary trunk and above the left atrium. Between the ascending aorta and superior vena cava, it is connected with the pericardial cavity proper. However, this connection was not depicted on the electron-beam CT images in this study. The transverse sinus was identified in 95 (95%) patients. It extends upward along the ascending aorta, where it forms the superior aortic recess (Figs 2, 4). The superior aortic recess is frequently depicted on CT images and was one of the first recesses described in CT studies of the mediastinum (4–6). Other authors (2) previously divided the superior aortic recess into anterior, posterior, and right lateral portions. Although the communication between the anterior portion and right lateral portion was sometimes visible in our study, we could never clearly identify the connection between the right lateral portion and posterior portion that runs between the ascending aorta and superior vena cava. Occasionally, the anterior portion extended downward to the level of the right atrium (Fig 4). The anterior and right lateral portions are directly related to the thymus, and the posterior portion is related to the tracheobronchial lymph nodes.
On nonenhanced CT images and magnetic resonance images, the superior aortic recess may also simulate aortic dissection or thrombus (3,6). The left pulmonic recess (Figs 2, 3) is situated below the left pulmonary artery and posterolateral to the proximal portion of the right pulmonary artery. Protopapas and Westcott (3) demonstrated the different appearances of this recess and discussed the diagnostic problems that may lead to a misdiagnosis of lymphadenopathy. The right pulmonic recess (Fig 3) lies below the right pulmonary artery and above the left atrium. Its posterior circumference is directly related to the inferior tracheobronchial lymph nodes. The inferior aortic recess (Fig 4) lies between the ascending aorta and either the inferior portion of the vena cava superior or the right atrium. Vesely and Cahill (1) demonstrated that the inferior aortic recess extends down to the level of the aortic valve. However, in our series, we could not identify this recess to that extent.
At the arterial reflections of the pericardium, the superior aortic recess is directly attached to the aortic wall. Posterior to the ascending aorta and main pulmonary artery, there may be a variable amount of epicardial fat. At CT, this was frequently seen as a fat space between these vessels on the one hand, and the transverse sinus, inferior aortic recess, and left pulmonic recess on the other. Only the right-sided entrance of the transverse sinus always directly attached to the posterior aspect of the ascending aorta. Often, there was a clear separation by fat between the left pulmonic recess and either the main pulmonary artery or the left atrial appendage.
Oblique Sinus
The oblique sinus (Figs 3, 4) is located behind the left atrium. In its cranial portion, it is separated from the transverse sinus by a double reflection of the pericardium between the right and left superior pulmonic veins. At CT, the transverse sinus, including the right and left pulmonic recesses, was always clearly separated from the oblique sinus, including the posterior pericardial recess, by a fat plane (Figs 2, 3). The upper right lateral extension of the oblique sinus is the posterior pericardial recess (Fig 2), which lies behind the distal right pulmonary artery and medial to the bronchus intermedius. In a former radiology report (2), the oblique sinus and posterior pericardial recess were seen at CT in less than 10% of patients. We observed them in 89 (89%) and 67 (67%) of 100 patients, respectively. The esophagus runs posterior to the oblique sinus, and the inferior tracheobronchial lymph nodes are in close proximity to these structures. The upper circumference of the oblique sinus and posterior pericardial recess is frequently surrounded by fatty tissue. In the present study, at CT, this often delineated these structures from the right pulmonary artery and right bronchus intermedius, and from the upper portion of the left atrium. More caudally, the oblique sinus is attached to the adventitia of the left atrium. Because the pericardium is separated from the esophagus by loose connective tissue, the esophagus was frequently separated from the oblique sinus by a fat space on the CT images in this study.
Summary
With the advent of fast imaging methods that provide high temporal and spatial resolution, the pericardial sinuses and recesses have been more frequently identified on imaging studies of the mediastinum. In general, pericardial sinuses and recesses may be difficult to differentiate from lymph nodes, esophageal or thymic processes, or vascular abnormalities. Rarely, pericardial cysts or tumors, which can mimic cardiac tumors, may develop in these sinuses and recesses (9).
In former studies (3,4,6), the more cranial recesses such as the superior aortic and left pulmonic recesses mainly were described. Less attention was paid to the caudal aspects of the sinuses—that is, the right pulmonic recess, inferior aortic recess, oblique sinus, and pulmonary vein recesses. This may be because the caudal recesses are more affected by heart motion than are the superior recesses—that is, the superior aortic recess and left pulmonic recess. In addition, the superior recesses are largely surrounded by fatty tissue, which makes them more delineated. The inferior recesses are often close to the esophagus or surrounded mainly by cardiac chambers, which makes the exact delineation of these structures more difficult. In general, the more mediastinal fat present, the better one can see the sinuses and recesses at CT.
In the present study, separations by fat planes were frequently observed between the sinuses or recesses and the intrapericardial structures (eg, between the transverse sinus and main pulmonary artery or between the left pulmonic recess and main pulmonary artery) and between the sinuses or recesses and the extrapericardial structures (eg, between the right pulmonic recess and right pulmonary artery or between the oblique sinus and esophagus). However, there were certain locations where the sinuses and recesses always directly abutted the adjacent intrapericardial structures—for example, between the superior aortic recess and ascending aorta, between the pulmonary vein recesses and proximal pulmonary veins, between the postcaval recess and superior vena cava, and between the right-sided entrance of the transverse sinus and the posterior aspect of the ascending aorta. In this context, it should be stated that the transition from water to fat was not always clearly identifiable, but rather it was occasionally blurred by image noise, especially in patients with a large volume of adipose tissue.
Soulen et al (10) described changes in pericardial fluid distribution due to heart motion and respiratory maneuvers in dogs with pericardial effusion. Because the pericardial sinuses and recesses are extensions of the pericardial cavity proper, it is very likely that pericardial fluid might move from one area to another during the cardiac cycle or during respiration (3). However, this was not investigated in our study, because we used constant conditions, with the CT images obtained at the end of diastole and in the middle of inspiration.
In conclusion, when electrocardiographically triggered electron-beam CT is performed, the pericardial sinuses and recesses are frequently observed on images of the heart. Knowledge of the location of these structures helps the radiologist avoid a misdiagnosis of lymphadenopathy or other mediastinal disease processes.
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Footnotes
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Author contributions: Guarantor of integrity of entire study, R.G.; study concepts, R.G., R.R.; study design, R.G., R.R.; definition of intellectual content, R.G., R.R.; literature research, R.G.; data acquisition and analysis, R.G., G.J.S.; manuscript preparation, editing, and review, R.G., R.R.
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References
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Kubota H, Sato C, Ohgushi M, Haku T, Sasaki K, Yamaguchi K. Fluid collection in the pericardial sinuses and recesses: thin-section helical computed tomography observations and hypothesis. Invest Radiol 1996; 31:603-610.[Medline]
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Aronberg DJ, Peterson RR, Glazer HS, Sagel SS. The superior sinus of the pericardium: CT appearance. Radiology 1984; 153:489-492.[Abstract/Free Full Text]
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Levy-Ravetch M, Auh YH, Rubenstein WA, Whalen JP, Kazam E. CT of the pericardial recesses. AJR 1985; 144:707-714.[Abstract/Free Full Text]
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Shabetai R. Anatomy In: The pericardium. New York, NY: Grune & Stratton, 1981; 1-32.
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Moncada R, Baker M, Salinas M, et al. Diagnostic role of computed tomography in pericardial heart disease: congenital defects, thickening, neoplasms, and effusions. Am Heart J 1982; 103:263-282.[Medline]
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Soulen RL, Lapayowker MS, Cortes FM. Distribution of pericardial fluid: dynamic and static influences. AJR 1968; 103:583-588.[Free Full Text]
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Abstract
Introduction
