Development and Evaluation of a Novel Curved Biopsy Device for CT-Guided Biopsy of Lesions Unreachable Using Standard Straight Needle Trajectories.
OBJECTIVE
To evaluate the feasibility of a novel curved CT-guided biopsy needle prototype with shape memory to access otherwise not accessible biopsy targets.


METHODS
A biopsy needle curved by 90° with specific radius was designed. It was manufactured using nitinol to acquire shape memory, encased in a straight guiding trocar to be driven out for access of otherwise inaccessible targets. Fifty CT-guided punctures were conducted in a biopsy phantom and 10 CT-guided punctures in a swine corpse. Biposies from porcine liver and muscle tissue were separately gained using the biopsy device, and histological examination was performed subsequently.


RESULTS
Mean time for placement of the trocar and deployment of the inner biopsy needle was ~205 ± 69 and ~93 ± 58 s, respectively, with a mean of ~4.5 ± 1.3 steps to reach adequate biopsy position. Mean distance from the tip of the needle to the target was ~0.7 ± 0.8 mm. CT-guided punctures in the swine corpse took relatively longer and required more biopsy steps (~574 ± 107 and ~380 ± 148 s, 8 ± 2.6 steps). Histology demonstrated appropriate tissue samples in nine out of ten cases (90%).


CONCLUSIONS
Targets that were otherwise inaccessible via standard straight needle trajectories could be successfully reached with the curved biopsy needle prototype. Shape memory and preformed size with specific radius of the curved needle simplify the target accessibility with a low risk of injuring adjacent structures.
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany. mschulze@ukaachen.de.
Maximilian Franz
MF
Schulze-Hagen
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Jochen
J
Pfeffer
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Markus
M
Zimmermann
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Martin
M
Liebl
Department of Pathology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Saskia Freifrau
SF
von Stillfried
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Christiane
C
Kuhl
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Philipp
P
Bruners
Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Peter
P
Isfort
D000818:Animals; D001707:Biopsy, Needle / Q000379:methods; D004867:Equipment Design; D005240:Feasibility Studies; D061705:Image-Guided Biopsy / Q000295:instrumentation; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology; D023421:Models, Animal; D009339:Needles; D019047:Phantoms, Imaging; D015641:Radiography, Interventional / Q000379:methods*; D013552:Swine; D014057:Tomography, X-Ray Computed / Q000379:methods*
CT-guided biopsy; Curved biopsy device; Curved needle; Nitinol