Endobronchial Ultrasonography (EBUS) can assess the endobronchial area and peri-bronchial structures. EBUS reveals abnormal findings in central airways via brochoscopy and is used to assess the diameter and length of the affected airway or depth of tracheobronchial tumor to select the most suitable stent. To assess the usefulness of EBUS, we compared findings of the EBUS images with 3D-CT.
From April 2006 to December 2008, we performed airway stenting on 19 patients, 15 malignant and 4 benign. We then compared pre-operative EBUS images and 3D-CT to assess the narrowing area of the airway at 138 points. Of these, 66 were considered normal, while 72 points were affected. For the 15 patients with malignant stenosis, measurements were taken at 92 places including 38 normal and 54 abnormal sites. Using EBUS, the size of the airway can be measured in real time during the procedure. When the EBUS probe is retrieved from the distal side of the stenosis to the proximal side with the balloon inflated, the shape of the balloon changes according to the degree of stenosis.
Diameter and length of the affected area measured by EBUS and 3D-CT were near equal in all patients. Significant correlations were seen at all 138 sites (r = 0.758, p < 0.0001), and for both 66 normal (r = 0.623, p < 0.0001) and 72 affected sites (r = 0.623, p < 0.0001). For malignant cases, significant correlations were noted for the total 92 sites (r = 0.781, p < 0.0001), while both 38 normal (r = 0.801, p < 0.0001) and 54 abnormal (r=0.758, p < 0.0001) were correlated.EBUS is also useful to assess improvements for airway stenosis post operation, such as laser ablation or ballooning, and for observing the sequence of changes in airway diameters.
In airway stenting, by measuring the size of the balloon on the EBUS image, it is possible to establish the suitable size of the stent.
This method is useful for malignant stenosis during interventional bronchology.
Seiichi Nobuyama, No Financial Disclosure Information; No Product/Research Disclosure Information