The Posterior Pericardial Recess: Potential for Confusion at Endobronchial Ultrasound.

Pericardial recesses are formed at sites of reflection of the visceral to parietal pericardium around the great vessels of the mediastinum. Identification at endobronchial ultrasound (EBUS) of a "high-riding" superior pericardial recess, masquerading as a lower paratracheal lymph node, has previously been reported. Although the potential for the posterior pericardial recess to be seen in the subcarinal region on computed tomography has been described in the radiology literature, its identification with EBUS has not. We report a case where the posterior pericardial recess was seen with EBUS in the lower subcarinal region adjacent to the bronchus intermedius. It can be clearly differentiated from a lymph node or vascular structure due to its hypoechoic appearance and lack of a color Doppler signal. Bronchoscopists should be aware of the potential to image the posterior pericardial recess with EBUS in the subcarinal region, to avoid confusion at the time of endoscopy.