Biopsy of peripheral lung nodules enhanced by 3D image guidance: Study
Netherlands: A recent study has revealed that a cone-beam (CBCT)-guided and augmented fluoroscopy-guided navigation bronchoscopy can yield 90% accuracy in biopsying peripheral lung lesions. The study findings are published in the Journal of Bronchology & Interventional Pulmonology.
According to the lead author, Roel L.J. Verhoeven, Department of Pulmonary Diseases, Radboud University Nijmegen Medical Centre, The Netherlands, and the team, navigation bronchoscopy using CBCT and [augmented fluoroscopy] imaging as a sole technique for both navigation and sampling is a (relatively) safe and accurate procedure for the diagnosis of small peripheral pulmonary lesions.
The researchers performed an observational study on over 200 patients who received CBCT-guided navigation bronchoscopy that included a CBCT image overlay on fluoroscopy imaging. Although there was an initial learning curve and imaging protocols needed to be modified and tailored to the procedure, the image-guided endobronchial lung biopsy method eventually yielded 90% accuracy -- and a much lower effective radiation dose for patients and staff.
CBCT can acquire intraprocedural 3D information, a valuable benefit for positioning of biopsy tools. The modality can also enable what the researchers called "augmented fluoroscopy," a technique that provides a navigation pathway and lesion position as an overlay on 2D fluoroscopic imaging, according to the researchers.
"With this combination of features, CBCT has the potential to meticulously help guide the endoscopist during the different aspects of the procedure," the authors wrote.
The researchers sought to assess exposure and procedural diagnostic accuracy over time in a prospective evaluation of 238 consecutive patients at Radboud between December 2017 and June 2020. After exclusion criteria were applied, 100 cases were available for radiation dose analysis, and 208 patients with a total of 248 lesions were included in the accuracy analysis. Of the 208 patients, a primary CBCT and augmented fluoroscopy approach was performed in 150 cases; a primary electromagnetic navigation approach was utilized in the remaining 58 cases.
The research yielded the following findings:
- There was a significant improvement in the dose-area product (DAP) and accuracy over time due to factors such as gaining more experience with using the method, fine-tuning of CBCT and fluoroscopy imaging protocols for the procedure, and replacing their CBCT system with an Azurion angiography system (Philips).
- The lowered radiation dose was primarily attributable to the implementation of lower-dose fluoroscopy protocols, which led to drop in average fluoroscopy DAP from 19 Gy·cm2 to 2.2 Gy·cm2. This dose reduction was achieved despite an increase in average total fluoroscopy time from 9.9 minutes to an average of 15.6 minutes.
"Considering the accuracy of the CBCT-guided navigation bronchoscopy, the procedural radiation burden for the patient when related to other procedures, and the associated cost of some of the additional navigation guidance modalities, one needs to individually assess if having multiple navigation guidance modalities remains worthwhile," the authors wrote. "On the basis of our experience, the added value of CBCT and [augmented fluoroscopy] when compared with other non–real-time navigation technology such as [electromagnetic navigation] is greatest in lesions needing more meticulous positioning."
Verhoeven, Roel L.J. MSc*; van der Sterren, William MSc†; Kong, Wens MSc‡; Langereis, Sander PhD†; van der Tol, Pieternel MSc‡; van der Heijden, Erik H.F.M. MD, PhD* Cone-beam CT and Augmented Fluoroscopy–guided Navigation Bronchoscopy, Journal of Bronchology & Interventional Pulmonology: October 2021 - Volume 28 - Issue 4 - p 262-271 doi: 10.1097/LBR.0000000000000783