Print Email Facebook Twitter The influence of tip shape on bending force during needle insertion Title The influence of tip shape on bending force during needle insertion Author van de Berg, N.J. (TU Delft Medical Instruments & Bio-Inspired Technology) de Jong, T.L. (TU Delft Medical Instruments & Bio-Inspired Technology) van Gerwen, D.J. (TU Delft Medical Instruments & Bio-Inspired Technology) Dankelman, J. (TU Delft Medical Instruments & Bio-Inspired Technology) van den Dobbelsteen, J.J. (TU Delft Medical Instruments & Bio-Inspired Technology) Date 2017 Abstract Steering of needles involves the planning and timely modifying of instrument-tissue force interactions to allow for controlled deflections during the insertion in tissue. In this work, the effect of tip shape on these forces was studied using 10 mm diameter needle tips. Six different tips were selected, including beveled and conical versions, with or without pre-bend or pre-curve. A six-degree-of-freedom force/torque sensor measured the loads during indentations in tissue simulants. The increased insertion (axial) and bending (radial) forces with insertion depth-the force-displacement slopes-were analyzed. Results showed that the ratio between radial and axial forces was not always proportional. This means that the tip load does not have a constant orientation, as is often assumed in mechanics-based steering models. For all tip types, the tip-load assumed a more radial orientation with increased axial load. This effect was larger for straight tips than for pre-bent or pre-curved tips. In addition, the force-displacement slopes were consistently higher for (1) increased tip angles, and for (2) beveled tips compared to conical tips. Needles with a bent or curved tip allow for an increased bending force and a decreased variability of the tip load vector orientation. Subject Biomedical engineeringScientific data To reference this document use: http://resolver.tudelft.nl/uuid:73276743-0520-4d3f-92fa-befcfc0a3bcf DOI https://doi.org/10.1038/srep40477 ISSN 2045-2322 Source Scientific Reports, 7 Part of collection Institutional Repository Document type journal article Rights © 2017 N.J. van de Berg, T.L. de Jong, D.J. van Gerwen, J. Dankelman, J.J. van den Dobbelsteen Files PDF srep40477.pdf 820.09 KB Close viewer /islandora/object/uuid:73276743-0520-4d3f-92fa-befcfc0a3bcf/datastream/OBJ/view