Designing and validating a PVA liver phantom with respiratory motion for needle-based interventions

Purpose: The purpose is to design and validate an anthropomorphic polyvinyl alcohol (PVA) liver phantom with respiratory motion to simulate needle-based interventions. Such a system can, for example, be used as a validation tool for novel needles. Methods: Image segmentations of CT scans of four patients during inspiration and expiration were...

A Rigid Multibody Model to Study the Translational Motion of Guidewires Based on Their Mechanical Properties

During percutaneous coronary interventions (PCI), a guidewire is used as an initial way of accessing a specific vasculature. There are varieties of guidewires on the market and choosing an appropriate one for each case is critical for a safe and successful intervention. The main objective of this study is to predict the behavior of the guidewire...

A variable stiffness mechanism for steerable percutaneous instruments: Integration in a needle

Needles are advanced tools commonly used in minimally invasive medical procedures. The accurate manoeuvrability of flexible needles through soft tissues is strongly determined by variations in tissue stiffness, which affects the needle-tissue interaction and thus causes needle deflection. This work presents a variable stiffness mechanism for...

Measuring surgical safety during minimally invasive surgical procedures: A validation study

Background: During the implementation of new interventions (i.e., surgical devices and technologies) in the operating room, surgical safety might be compromised. Current safety measures are insufficient in detecting safety hazards during this process. The aim of the study was to observe whether surgical teams are capable of measuring surgical...

Needle placement errors: do we need steerable needles in interventional radiology?

Purpose: Accurate and precise needle placement is of utmost importance in interventional radiology. However, targeting can be challenging due to, eg, tissue motion and deformation. Steerable needles are a possible solution to overcome these challenges. The present work studied the clinical need for steerable needles. We aimed to answer three...

Electrosurgery: short-circuit between education and practice

Introduction: Electrosurgery is used in 80% of surgical procedures. The technique allows surgeons to skilfully dissect tissues and achieve haemostasis. Since improper use of electrosurgery can lead to serious adverse events, training is required to potentially reduce the number and severity of these events. In this study we evaluate education...

Surgical flow disturbances in dedicated minimally invasive surgery suites:: An observational study to assess its supposed superiority over conventional suites

Background: Minimally invasive surgery (MIS) is frequently compromised by surgical flow disturbances due to technology- and equipment-related failures. Compared with MIS in a conventional cart-based OR, performing MIS in a dedicated integrated operating room (OR) is supposed to be beneficial to patient safety. The aim of this study was to...

Endpoint accuracy in manual control of a steerable needle

Purpose<br/>To study the ability of a human operator to manually correct for errors in the needle insertion path without partial withdrawal of the needle by means of an active, tip-articulated steerable needle.<br/><br/>Materials and Methods<br/>The needle is composed of a 1.32-mm outer-diameter cannula, with a flexure joint near the tip, and a...

Dataset on force measurements of needle insertions into two ex-vivo human livers

A needle-tissue interaction experiment has been carried out, by inserting the inner needle of a trocar needle into two ex-vivo human livers. The dataset contains the forces that act on the needle during insertion and retraction into the livers. In addition, a MATLAB code file is included that provides base-level analysis of the data and...

PVA matches human liver in needle-tissue interaction

Medical phantoms can be used to study needle-tissue interaction and to train medical residents. The purpose of this research is to study the suitability of polyvinyl alcohol (PVA) as a liver tissue mimicking material in terms of needle-tissue interaction. Insertions into ex-vivo human livers were used for reference. Six PVA samples were...

The art of electrosurgery: Trainees and experts

The benefits of electrosurgery have been acknowledged since the early 1920s, and nowadays more than 80% of surgical procedures involve devices that apply energy to tissues. Despite its widespread use, it is currently unknown how the operator's choices with regard to instrument selection and application technique are related to complications....

Manually controlled steerable needle for MRI-guided percutaneous interventions

This study aims to develop and evaluate a manually controlled steerable needle that is compatible with and visible on MRI to facilitate full intra-procedural control and accurate navigation in percutaneous interventions. The steerable needle has a working channel that provides a lumen to a cutting stylet or a therapeutic instrument. A steering...

The influence of tip shape on bending force during needle insertion

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,...

Delicate balance: Adaptive support to improve patient safety

‘It is time to prepare the next patient’ real-time prediction of procedure duration in laparoscopic cholecystectomies

Operating Room (OR) scheduling is crucial to allow efficient use of ORs. Currently, the predicted durations of surgical procedures are unreliable and the OR schedulers have to follow the progress of the procedures in order to update the daily planning accordingly. The OR schedulers often acquire the needed information through verbal...