Interventional Oncology
Mathew Macey, DO
Resident
Department of Radiology, Lahey Hospital and Medical Center, Tufts University Medical School, Burlington, MA, US
Disclosure(s): No financial relationships to disclose
Christopher Molgaard, MD
Attending
Department of Radiology, Lahey Hospital and Medical Center, Tufts University Medical School, Burlington, MA, US
Rajendran Vilvendhan, MD
Attending
Department of Radiology, Lahey Hospital and Medical Center, Tufts University Medical School, Burlington, MA, US
Moran Shochat, n/a
SVP Strategic Innovations
XACT Robotics
Danielle Bradbury, n/a
Senior Director, Clinical Development
XACT Robotics
Sebastian Flacke, MD PhD
Attending
Department of Radiology, Lahey Hospital and Medical Center, Tufts University Medical School, Burlington, MA, US
A prospective registry study included 18 clinically indicated biopsies of lung lesions, to date. CT datasets were obtained for planning and controlled needle placement of 19 G needles using a patient-mounted, CT-guided robotic system with 5° freedom. Planning included target selection, skin entry point, and predetermined checkpoints where additional imaging was performed to permit stepwise correction of needle trajectory. Imaging and needle advancement were timed for the end-expiratory phase of respiration. The robotic system responds to target adjustment in plane and through plane at each checkpoint by deviating from a primarily linear trajectory according to the operator’s input.
Success rate, needle tip to target distance, number of checkpoints used, number of trajectory corrections, procedure duration and adverse events were recorded. Data are given as mean ± standard deviation.
Results: Study population consisted of 12 men and 6 women, average age 72.8 ± 10.3 years. 8 procedures were performed in the prone position, 5 in supine and 5 in lateral decubitus position. Average skin to lesion distance was 6.4 ± 2.2 cm (range 3.3 -10.6 cm).
In 15 of 18 procedures (83.3%) the robot positioned a 19 G diamond tip trocar needle successfully on target. Overall accuracy (needle tip to target distance) was 1.4 ± 0.74 mm (range 0.1-3 mm). The average required time between initial registration scan and reaching the target was 12.2 ± 4.7 min. The average number of checkpoints was 1.7 ± 0.75 (range 1-3). Target adjustment due to target movement and subsequent trajectory correction was required in 9 procedures (60.0%). The magnitude of target correction in 3-dimensions varied from 2 to 9 mm. Once the trocar guided needle reached desired position, coaxial 20 G core needle passes were made for specimen acquisition.
Three out of the 15 patients (20%) in whom the robot positioned the trocar needle successfully developed a pneumothorax, which was managed until resolution with observation (n=2) or chest tube placement and observation (n=1).
In 2 of the remaining patients the procedure was manually performed by the operator. Both patients were unable to follow breathing instructions and target movement required repositioning of the needle. One case was aborted due to a technical failure of the CT scanner.
Conclusion: Accurate needle targeting of lung lesions within 2 mm error with a single pleural puncture can be achieved in patients when using a CT-guided robotic system.