LAUSR

We read with interest the article by Shen et al., published in the recent issue of the journal. The authors have evaluated the role of multi-slice spiral computed tomography (CT) for the diagnosis of tracheobronchial foreign body aspiration in 382 children over a fiveyear period. The majority of the children (~69%) were in the age group of 1–2 years and the majority of foreign bodies were located in the right or left main bronchus (95.3%). The presence of a foreign body could be established directly in 95.5% of the cases. The authors have concluded that computed tomography is very sensitive in the detection of tracheobronchial foreign bodies and its timely diagnosis is very crucial to prevent sequelae in children. We agree with the authors’ observations and we wish to highlight another advantage of CT virtual bronchoscopy, which can be performed in these children with foreign body aspiration. As most of the present generation CT scanners are multidetector technology and the images are acquired in volume mode (spiral mode), CT virtual bronchoscopy can be performed from the same data set (in these children) once it has been acquired by simple use of virtual navigation software, which is available with most of the computed tomography vendors. No extra examination or study has to be performed and no additional radiation exposure is involved. The same computed tomography data, once acquired, just needs to be reconstructed and navigated using the virtual navigation software for airways and we can have access to noninvasive virtual bronchoscopy images in these children with foreign bodies. These can be useful for surgeons or pulmonologists, giving them a road map for bronchoscopy before doing the actual procedure. It also has the added advantage of providing information about the lung segments distal to the obstruction, which is not possible with rigid / flexible bronchoscopy. Sodhi et al. evaluated the potential use of multidetector CT (MDCT) and virtual bronchoscopy (VB) in the evaluation of tracheobronchial patency in 43 children with suspected bronchial obstruction and compared computed tomography findings with fiber-optic / rigid bronchoscopy or surgery. In their study, postprocessing was performed and virtual bronchoscopy and multiplanar reformations (MPR) were obtained at the same sitting. Based on their study, they found an excellent positive correlation between CT-virtual bronchoscopy and bronchoscopy / surgery. The authors concluded that CT-virtual bronchoscopy was useful in evaluating bronchial stenosis and obstruction caused by both endoluminal pathology and external compression and has the advantage of looking beyond stenosis. Its main application lies in providing the exact location of suspected foreign body, prior to bronchoscopy. Jung et al., in their retrospective study of 10 patients with foreign bodies, found three-dimensional CT virtual bronchoscopy (3D-CTVB) to be very sensitive in foreign-body location. In all of their cases, the foreign-body location, suspected on the preoperative 3D-CTVB, was consistent with the intraoperative bronchoscopy findings. Authors have recommended that the 3D-CTVB should be considered for the diagnosis of children with suspected bronchial foreign bodies. Computed tomography virtual bronchoscopy is a useful non-invasive imaging modality, which can help in the clinical management of these children with foreign bodies and its use should be further explored.