title: A quantitative and automatic echographic method for real-time localization of endovascular devices.
abstract: Current imaging methods for catheter position monitoring during minimally invasive surgery do not provide an effective support to surgeons, often resulting in the choice of more invasive procedures. This study was conducted to demonstrate the feasibility of non-ionizing monitoring of endovascular devices through embedded quantitative ultrasound (QUS) methods, providing catheter self-localization with respect to selected anatomical structures. QUS-based algorithms for real-time automatic tracking of device position were developed and validated on in vitro and ex vivo phantoms. A trans-esophageal ultrasound probe was adapted to simulate an endovascular device equipped with an intravascular ultrasound probe. B-mode images were acquired and processed in real time by means of a new algorithm for accurate measurement of device position. After off-line verification, automatic position calculation was found to be correct in 96% and 94% of computed frames in the in vitro and ex vivo phantoms, respectively. The average errors of distance measurements (bias ± 2SD) in a 41-step 10-cm-long parabolic pathway were 0.76 ± 3.75 mm or 0.52 ± 3.20 mm, depending on algorithm implementations. Our results showed the effectiveness of QUS-based tracking algorithms for real-time automatic calculation and display of endovascular system position. The method, validated for the case of an endoclamp balloon catheter, can be easily extended to most endovascular surgical systems.
authors: Bioengineering Division of the National Research Council, Institute of Clinical Physiology, Lecce, Italy.
authors: Francesco
authors: F
authors: Conversano
authors: Ernesto
authors: E
authors: Casciaro
authors: Roberto
authors: R
authors: Franchini
authors: Aimè
authors: A
authors: Lay-Ekuakille
authors: Sergio
authors: S
authors: Casciaro
mesh_terms: D000465:Algorithms; D000818:Animals; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging; D002404:Catheterization / Q000295:instrumentation / Q000379:methods*; D002417:Cattle; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D018084:Ultrasonography, Interventional / Q000295:instrumentation / Q000379:methods*