A novel approach involving reversed placement of endobronchial valves combined with retrograde methylene blue instillation for the localization of multifocal bronchopleural fistula.

The bronchopleural fistula (BPF) is a pathological communication between the bronchus and the pleural space. Diagnosing BPF poses a significant challenge for physicians, particularly when identifying multifocal BPFs. Traditionally, retrograde instillation of methylene blue (MB) into the pleural cavity with simultaneous observation with a bronchoscope has been used to locate a BPF. However, MB instillation is not effective in identifying multifocal BPFs. In this article, we report a new method for locating multifocal BPFs which involves placing the endobronchial valve (EBV) in reverse combined with retrograde MB instillation. First, the thoracic cavity is filled with MB solution. Then, using bronchoscopy, the location of a BPF can be identified as the MB solution flows into the bronchus. Secondly, an EBV is deployed in reverse in the bronchus where the identified BPF is located. Retrograde MB instillation is then repeated to locate any additional BPFs until no new ones are found. Two cases were reported using this novel method to identify multifocal BPFs, and each case was ultimately diagnosed with 2 BPFs. After precisely locating all the BPFs, the EBVs are then removed and placed forward in the target bronchi for treating the BPFs. During the follow-up period, no recurrence of BPFs was observed. We conclude that reversed placement of EBVs combined with retrograde MB instillation appears to be an effective approach for locating multifocal BPFs.