Comparing three-dimensional models of placenta accreta spectrum with surgical findings.

Objective: Placenta accreta spectrum (PAS) is associated with significant maternal morbidity mainly related to blood loss. Pre-operative planning is aided by antenatal ultrasound and magnetic resonance imaging. We sought to assess whether three-dimensional (3D) models from MR images were accurate when compared with surgical and pathological findings.

Comparative ergonomic workflow and user experience analysis of MRI versus fluoroscopy-guided vascular interventions: an iliac angioplasty exemplar case study.

Purpose: A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics.

Methods: Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions.

Heating and safety of a new MR-compatible guidewire prototype versus a standard nitinol guidewire.

Our purpose in this study was to examine heating of nitinol and polyetheretherketone (PEEK) guidewires during near-real-time MR imaging in an artificial vascular model an "aorta phantom". The first 100 cm of the nitinol- and PEEK-based guidewires both 145 × 0.08 cm were immersed in a saline-filled aorta phantom.

Liver displacement during ventilation in Thiel embalmed human cadavers - a possible model for research and training in minimally invasive therapies.

Respiration-related movement of organs is a complication in a range of diagnostic and interventional procedures. The development and validation of techniques to compensate for such movement requires appropriate models. Human cadavers embalmed with the Thiel method remain flexible and could provide a suitable model.

Evaluation of an active vena cava filter for MR imaging in a swine model.

Purpose: To evaluate the feasibility of magnetic resonance (MR) imaging-guided placement of an active vena cava filter (AVCF) in a swine model, the effectiveness of the system in filtering thrombi, and the detection of thrombi with MR imaging.

Materials And Methods: This study was approved by the government committee on animal investigations. An AVCF tuned to the Larmor frequency of a 1.

Experimental MRI visible resonant prosthetic heart valves.

Artificial heart valves comprising metal can cause significant MR image artifacts due to the material (susceptibility artifact) and/or electromagnetic characteristics (RF artifact). The purpose of our study was to examine current commercially available heart valve prostheses, integrate resonant circuits and to produce a prototype self-expanding heart valve for MRI-guided placement. Different types of commercially available heart valves were tested in MRI.

Improvement of the MR imaging behavior of vascular implants.

Vascular implants can cause significant MR image artifacts due to the material (susceptibility artifact) or the electromagnetic characteristics (RF artifact). These artifacts are caused by the distortion of the magnetic field and interferences with the radio frequency (RF) waves of the MR imaging process. Void or complete vanishing of signals occurs in close proximity or inside implants.