Robotic-assisted Bronchoscopy Combined with Multimodal Imaging for Targeted Lung Cryobiopsies

A component of our interventional pulmonology research is to describe the outcomes of our procedures. With new developments in advanced diagnostic bronchoscopy, we wish to detail our experiences as we aim to improve diagnostic yield, safety, radiation exposure, and efficiency of procedures at our institution. Robotic-assisted bronchoscopy is a new technique to obtain targeted lung biopsies.

We use this technology in a multimodality approach with radial endobronchial ultrasound, cone-beam computed tomograph, and fluoroscopy. The obtained transbronchial lung cryobiopsies are useful in the evaluation of pulmonary lesions or selected areas in diffuse parenchymal lung disease. Our group has published outcomes with the concurrent use of shape-sensing robotic-assisted bronchoscopy combined with fixed cone-beam CT and radial EBUS in the evaluation of peripheral pulmonary lesions.

We reported our diagnostic accuracy outcomes in our initial 200-patient cohort and published a subsequent study describing the radiation exposure and outcomes in 241 patients using this multimodality technique. To begin, upload the patient's thin slice CT chest to the planning software. After selecting the targets in the lungs, plan a pathway to each target site and review the plan in the axial, coronal, and sagittal views in virtual bronchoscopy.

After preparing for the procedure, maneuver the catheter through the airways to the target lesion following the planned pathway. Using the preview path feature, follow the images of the airways if divergence is noted. Remove the vision probe when the catheter is within 5 to 10 millimeters of the target lesion and advance the radial endobronchial ultrasound or R-EBUS probe with rotation under fluoroscopy to the pleural border.

Retract the R-EBUS probe under fluoroscopy approximately 10 millimeters from the pleural border to the anticipated biopsy target site. Visualize the target area to assess the surrounding parenchyma and any vasculature. After removing the R-EBUS probe, insert the 1.1 millimeter touch cryo probe via the catheter and extend under fluoroscopy to the predetermined target area for biopsy.

Perform cone-beam CT spin per system specific protocol. Interpret and compare the intra procedure imaging to the pre-procedure CT chest and plan for the correct catheter position. If augmented fluoroscopy is available on the CBCT, segment the target for visualization with 2D fluoroscopy during biopsy.

Adjust the catheter based on fluoroscopy CBCT and R-EBUS to ensure that sampling occurs in the appropriate location. Press the pedal to activate the freeze cycle from four to six seconds and retract the probe in one motion while depressing the pedal. Release the pedal as the probe tip with tissue is placed in 0.9%sodium chloride or fixative to release it.

After the final biopsy, inject one to two milliliters of normal saline and air in a 10 milliliter luer lock syringe into the catheter to clear any blood or secretions. Insert the vision probe to view the sampling site and retract the catheter slowly. Finally, if there is no evidence of bleeding, retract the catheter to the trachea.

Post-procedure chest radiograph in anterior-posterior view showed bilateral interstitial densities with no pneumothorax or pleural effusion.