Bronchial atresia is a congenital anomaly resulting from the focal interruption of a lobar, segmental, or subsegmental bronchus with associated peripheral mucus impaction (bronchocele, mucocele) and hyperinflation of the obstructed lung segment [1]. CT is the most sensitive imaging modality and can characterize the lack of communication between the mucocele and the pulmonary hilum [3, 4]. A typical radiographic finding of bronchial atresia is a branching tubular or nodular area of increased opacity that extends from the hilum with surrounding hyperlucent lung parenchyma [6].
Although no surgical intervention is necessary for asymptomatic patients, careful observation of individual cases is required. Bronchial atresia can often cause severe pulmonary infections that cannot be controlled by antibiotics; thus, the treatment option would be the resection of the abnormal regions [3]. In addition, abnormal nodules can appear in the affected area. It is extremely difficult to make an accurate diagnosis from an abnormal nodule or mass by bronchofiberscopy because of the lack of bronchi in a tumor. Lobectomy is the most frequently reported procedure for the treatment of a pulmonary lobe with such an abnormal region [7]. However, segmentectomy is more appropriate for diagnostic therapy because it causes minimal respiratory impairment. This method is sometimes challenging since the residual normal lung tissue is usually compressed by the emphysematous area, and the intersegmental plane changes are unclear [8]. Since congenital bronchial atresia is not a malignant disease, a thoracoscopic approach should be performed whenever possible [9].
In our case, as the patient did not have any symptoms or history of pneumonia, we could not completely exclude the possibility of a malignant tumor. However, it was difficult to obtain the correct diagnosis from the detected abnormality as bronchofiberscopy and CT-guided biopsy were not suitable because of the bronchial obstruction. In this case, B6c was found to be obstructed by bronchoscopy. In addition, emphysematous changes in the lung parenchyma affected the entire S6; therefore, it was easy to determine the extent of resection. We decided that segmentectomy was the appropriate procedure for the treatment. When applied to other cases, we believe it is possible to determine the vessels to be resected by comprehensively judging the findings of bronchoscopy and CT.
For segmentectomy operation, there are two well-known methods. One uses selective segmental inflation via bronchofiberscopy and the other uses ICG dye [10, 11]. The ICG dye was developed for near infra-red photography and was approved for clinical use in 1959 by the Food and Drug Administration [12]. ICG binds rapidly to plasma lipoproteins and becomes fluorescent when excited by light or a laser beam at specific wavelengths in the near-infra-red spectrum (approximately 820 nm) [13]. The fluorescence can be detected using specific scopes and cameras (KARL STORZ, SE & Co. KG, Tuttlingen, Germany). Under the infrared light, the lung was clearly separated into two areas, in line with the existence of the blood flow on the monitor [14]. Then, we were able to perform a clear resection of the target region. Fluorescence navigation with ICG is a useful and safe method for the detection of the intersegmental border and can facilitate anatomical segmentectomy even when bronchial atresia causes an abnormal change in the lung anatomy. Despite the fact that selective segmental inflation using jet ventilation is also typically used in lung segmentectomy [10], ICG may be more appropriate in the resection of the hyperinflated area as it is impossible to put the bronchofiberscope into the obstructed bronchus. In addition, for the identification of the intersegmental plane, ICG use showed an 88.0% rate of good results, which was better than the 78.7% rate achieved by the high flow jet ventilation [11].
Segmentectomy using ICG is an appropriate technique for minimal resection without respiratory impairment and diagnostic therapy of bronchial atresia.
