Early Ct Findings Following Bronchial Thermoplasty

Introduction: Bronchial thermoplasty (BT) is a recent promising and well tolerated technique for the treatment of severe asthma. It acts by delivering thermal energy to airway walls and may induce pulmonary opacities on CT in the immediate post procedural time as previously reported (Pretolani M et al. AJRCCM 2014;190:1452-4). Aims and objectives: To examine early CT modifications following BT and to determine their association with respiratory symptoms. Background: Unenhanced chest CT was systematically performed the day after each BT session (ALAIR® device, Boston Scientific, Natick, MA, USA) in 13 severe asthmatics, leading to 38 treated lobes evaluated on day 1. In 11 patients, 15 BT-treated lobes were evaluated at 1 month. The first 2 patients had also a follow-up CT performed at 1 week. Background: No symptoms suggestive of pulmonary infection were noted following BT in any patient. Peribronchial consolidations and ground-glass opacities were observed in all treated lobes the day after BT, with 3 lower lobes showing complete collapse. Mild involvement of an adjacent untreated lobe was observed in 12/38 (32%) cases. Opacities had decreased in 5/15 (33%) and disappeared in 10/15 (67%) treated lobes at 1 month. Conclusion: BT induced early (24 h) pulmonary peribronchial hyperdensities in all treated lobes. These alterations were unrelated to clinical symptoms and they spontaneously decreased or disappeared after 1 month. These findings suggest that BT can promote lung inflammation or edema and that this effect extends to an adjacent untreated lobe, in approximately one third of cases.