COMPARISON OF REAL-TIME VIRTUAL AND FIBEROPTIC BRONCHOSCOPY IN PATIENTS WITH BRONCHIAL-CARCINOMA - OPPORTUNITIES AND LIMITATIONS

OBJECTIVE. Both helical CT and fiberoptic bronchoscopy are used in the staging of pulmonary tumors for therapeutic decision making. The impr oved resolution offered by helical CT has led to the clinical use of t hree-dimensional reconstruction techniques such as virtual bronchoscop y. We tested this new simulated endoscopic view of inner organ surface s and compared it with corresponding fiberoptic examinations of the tr acheobronchial system. SUBJECTS AND METHODS. Twenty patients with mali gnancies of the lung and mediastinum were examined with both virtual b ronchoscopy and fiberoptic bronchoscopy. Both examinations were review ed by radiologists and surgeons familiar with fiberoptic bronchoscopy. Virtual bronchoscopy was calculated and reconstructed from the cross- sectional images on a separate workstation. Stenoses and tumor infiltr ation were classified from the fiberoptic examination. These results w ere compared with the virtual bronchoscopy findings, RESULTS, Virtual bronchoscopy of diagnostic quality was achieved in 19 of 20 patients. High-grade stenoses were revealed equally well with virtual and fibero ptic techniques. Virtual bronchoscopy offered the advantage of being a ble to visualize areas beyond even high-grade stenoses. However, on vi rtual bronchoscopy discrete infiltration or extraluminal impression wa s not visible in five patients. In Mother patient, strong heart pulsat ion produced motion artifacts that prevented evaluation of the reconst ruction. CONCLUSION, Virtual bronchoscopy represents a new noninvasive method for evaluating helical CT findings. In comparison with fiberop tic bronchoscopy, virtual bronchoscopy offers the advantage of being a ble to visualize areas beyond even high-grade stenoses, In addition to the limited view of fiberoptic bronchoscopy, extraluminal causes of l umen compressions can be analyzed in the cross-sectional images and ev aluated together with the virtual representation. However, it was not possible to detect small infiltrations with virtual bronchoscopy. This new representation of helical CT data might be helpful for postoperat ive follow-up examinations, such as after stent implantation, and can be carried out without additional risk to the patient. Radiologists do need special fiberoptic bronchoscopy knowledge and experience with th ree-dimensional reconstructions to differentiate between real stenoses and artificial stenoses that might be caused by pulsation artifacts.