Induced pressures on the epiphyseal growth plate with non segmental anterior spine tethering.

Study Design: Experimental biomechanical study of pressures exerted on the epiphyseal growth plates (GP) in tethered porcine cadaveric spines.

Objectives: To experimentally measure the pressure exerted on the vertebral end plates of a tethered porcine spine model. Flexible spine tethering is a novel fusionless surgical technique that aims to correct scoliotic deformities based on growth modulation due to the pressure exerted on vertebral body epiphyseal GP.

Cyclically controlled vertebral body tethering for scoliosis: an in vivo verification in a pig model of the pressure exerted on vertebral end plates.

Study Design: Experimental in vivo study of the pressure exerted on the spine of a pig by a new cyclic anterior vertebral body tethering (AVBT) prototype.

Objectives: To evaluate the relationship between the tether tension and the pressures transmitted onto the vertebral end plates by a cyclic AVBT prototype. AVBT is a recent surgical technique for the treatment of pediatric scoliosis that compresses the convex side of the spine with a sustained tension, to modulate the growth to progressively correct the deformity over time.

A MRI-based platform for catheter navigation.

The development of minimally invasive surgical techniques using magnetism is expanding. Our research group is exploring catheter steering using the gradient field of a modified clinical Magnetic Resonance Imaging (MRI) system. This paper focuses on the upgrade of the MRI testing platform towards an integrated system allowing for in vitro and in vivo experiments.

Characterization of the deflections of a catheter steered using a magnetic resonance imaging system.

Purpose: The authors quantify the deflections of a catheter and a guidewire in MR setting with different designs of ferromagnetic tips and a system of high gradient coils which can generate gradients, and thus forces, 20 times larger than a conventional scanner.

Methods: Different designs of catheter tips are experimentally tested in an effort to maximize the deflections. One to two ferromagnetic spheres are attached at the distal tip of the catheter (or guidewire) with different spacing between the spheres.

Catheter steering using a Magnetic Resonance Imaging system.

A catheter is successfully bent and steered by applying magnetic gradients inside a Magnetic Resonance Imaging system (MRI). One to three soft ferromagnetic spheres are attached at the distal tip of the catheter with different spacing between the spheres. Depending on the interactions between the spheres, progressive or discontinuous/jumping displacement was observed for increasing magnetic load.