Virtual vs. reality in cone-beam CT-guided robotic-assisted bronchoscopy

The diagnostic accuracy of shape-sensing robotic bronchoscopy (ssRAB) is impacted by computed tomography-to-body divergence (CTBD) due to a discrepancy between virtual and actual lesion locations. The prevalence, types, implication, and determinants of CTBD during ssRAB remain understudied. This study aimed to qualify and quantify CTBD during cone-beam computed tomography (CBCT)-guided ssRAB and identify contributing factors.

This was an analysis of a prospectively curated database of patients who underwent mobile CBCT-guided ssRAB for the sampling of parenchymal lung lesions between October 2021 and June 2022. The primary outcome was the distance and vector of target displacement between the virtual preoperative CT-based and the actual intraoperative CBCT-based relationship between the tip of the ssRAB catheter and the target lesion.

A total of 81 lesions in 70 participants were included in the final analysis. Displacement was identified in 67% of targeted lesions. In 78% the ssRAB catheter was closer than expected (forward displacement) and an overshoot beyond the lesion occurred in 46% of displacement instances. In a multivariable logistic regression analysis, ≥7 traversed airway generations were independently associated with target lesion displacement. Despite a high level of displacement, there was no statistically significant difference in diagnostic yield rates between cases with and without displacement.

CTBD, i.e., displacement of the actual target lesion from the virtual location, is common during navigational bronchoscopy. When targeting peripheral lesions, the catheter is more likely to be closer to the lesion or beyond it than expected based on the virtual planning. Bronchoscopists should anticipate CTBD and integrate data from various intraoperative imaging tools to attenuate its impact on sampling and avoid potential complications.