Four cases of accessory cardiac bronchus incidentally detected on multi-detector CT

Accessory cardiac bronchus (ACB) is a rare bronchial anomaly. There have been many recent reports concerning CT diagnosis. Here, we assessed the frequency of ACB in our routine multi-detector CT examinations of the chest and presented several CT features. ACB was observed in four of 605 cases, representing a frequency of 0.66%. The origin of ACB was the medial wall of the intermediate bronchus in all cases. A normal B7 was identified in all cases. The inner diameter of ACB was 5.5–8.6 mm, and the length was 7.5–13.5 mm. The end of the ACB was blind in two cases. Both proper lobule and interlobar fissure were found in one case. Abnormal vessels were not identified in any cases. In all patients, MPR, MPVR, volume rendering and virtual endoscopy were performed. The ACB was demarcated by a spur at the origin in all cases. With the exception of one patient, none presented with symptoms related to ACB. No ACB was identified prospectively. Careful interpretation of the results of chest CT examination is required in patients with respiratory symptoms.