THREE-DIMENSIONALVIRTUAL BRONCHOSCOPY USING AN iPAD TO GUIDE IN REALTIME TRADITIONALTRANSBRONCHIAL NEEDLE ASPIRATION BIOPSY

Objectives: Three-dimensional (3D) imaging is reported to assist several surgical procedures, thus we assumed virtual endoscopy and curved-multi planar reconstructions (c-MPR) to be able to guide in real time "blind"-traditional TBNA and increase its diagnostic accuracy. Methods: One hundred and thirty-six consecutive patients with mediastinal adenopathy accessible to TBNAwere prospectively enrolled and randomly allocated to Experimental or Traditional Group depending on whether TBNA was performed with or without prospective 3D guidance. EBUS and/or surgical biopsy were performed if TBNA results were inadequate. All patients underwent chest MDCT scans (1 mm thickness) which were reconstructed in Open Osirix software to obtain both a c-MPR of trachea and of bronchi and a virtual endoscopy. C-MPR was used to predict a precise sampling location by measuring the distance of the node planned to biopsy from the carina. The static images were edited in dynamic endoscopic navigation by Open iMovie software and were transferred to iPAD to guide in real time TBNA. Sensitivity, specificity, PPV, and NPV were calculated in a standard manner for each group and McNemar test assessed the intergroup difference Results: Traditional and Experimental group counted 69/136 (51%) and 67/136 (49%) patients, respectively. No significant intergroup difference were found regarding demographic data, lymph node size (17 ± 2.9 vs 16 ± 3.4 mm; P = 0.6), stations sampled and operative time (14 ± 2 vs 13 ± 4 min). Sensitivity, specificity, NPV and PPV of Traditional Group were 68% (43/63); 100% (6/6); 23% (6/26) and 100% (43/43); and of Experimental Group were 86% (53/61); 100% (6/6); 57% (8/14) and 100% (53/53). The sensitivity was higher in the Experimental than in the Traditional group (86% vs 68%; P = 0.003). Conclusion: Our 3D virtual bronchoscopy is cost-effective, easily reproducible, and improves the diagnostic accuracy of traditional TBNA. Surgeons using an iPAD can follow simultaneously virtual and normal bronchoscopy step-by-step which helps to identify in real time the right sampling location of the lymph node.