Evaluation of Pulmonary Nodules Using the Spyglass Direct Visualization System Combined With Radial Endobronchial Ultrasound: A Clinical Feasibility Study

Background: Sampling of peripheral pulmonary nodules with radial endobronchial ultrasound (p-EBUS) increases diagnostic yield of bronchoscopy. However, diagnostic yield is influenced by numerous factors. Objective: We evaluated the use of SpyGlass, a one millimeter diameter optic fiber, to obtain images of the distal mucosa and of pulmonary lesions detected with p-EBUS to determine if visual aspect of the distal mucosa was predictive of diagnosis. Methods: We prospectively recruited subjects investigated for peripheral nodules. Bronchoscopy was performed and p-EBUS was used to locate the lesion through a guide sheath. The Spyglass fiber was introduced in the sheath to obtain images of the distal bronchial mucosa. Tissue sampling was subsequently done. Results: Fifteen patients were enrolled in the study. A final diagnosis of malignancy was confirmed in 80%. All lesions could be located using p-EBUS (100%). Diagnostic sensitivity for p-EBUS was 58.3%. Distal mucosa could be imaged with SpyGlass in 14/15 patients (93.3%). Mucosal appearance was described as abnormal in 7 out of the 15 subjects. Mean SpyGlass procedure time was 6.5 minutes. No direct complication was reported. Conclusion: Spyglass can be used in combination with p-EBUS to obtain images of the distal bronchial mucosa and peripheral pulmonary nodules. More patients will be needed to confirm whether mucosal appearance can be predictive of malignancy.