Complex Residual Attention U-Net for Fast Ultrasound Imaging from a Single Plane-Wave Equivalent to Diverging Wave Imaging.

Plane wave imaging persists as a focal point of research due to its high frame rate and low complexity. However, in spite of these advantages, its performance can be compromised by several factors such as noise, speckle, and artifacts that affect the image quality and resolution. In this paper, we propose an attention-based complex convolutional residual U-Net to reconstruct improved in-phase/quadrature complex data from a single insonification acquisition that matches diverging wave imaging.

Towards markerless computer assisted surgery: Application to total knee arthroplasty.

Purpose: A new approach is proposed to localise surgical instruments for Computer Assisted Orthopaedic Surgery (CAOS) that aims at overpassing the limitations of conventional CAOS solutions. This approach relies on both a depth sensor and a 6D pose estimation algorithm.

Methods: The Point-Pair Features (PPF) algorithm was used to estimate the pose of a Patient-Specific Instrument (PSI) for Total Knee Arthroplasty (TKA).

Learning ultrasound gesture database: building and application to musculoskeletal ultrasound exams.

Our aim is to develop a frame work for virtually learning the ultrasound exams. In this paper we address the method used to build the image database required for this frame work. The used materiel and the proposed methodology are presented and explained.

Finite element lifetime prediction of a miniature adjustable orthopedic device.

In Total Knee Arthroplasty (TKA), accurate balancing of the medial and lateral collateral ligaments is considered by orthopedic surgeons as one of the most challenging and complicated tasks to achieve. Therefore, an efficient solution is needed to assist the surgeons in achieving this crucial task without resulting in tibiofemoral misalignment. The required solution consists in developing either a completely automated smart ligament balancer for intraoperative use or adjustable tibial implant for postoperative use.

Ligament imbalance metrics and an autonomous measurement system for post TKA.

This paper describes two useful metrics to estimate the ligament imbalance for post Total Knee Arthroplasty (TKA) scenario: the center of pressure and the net moments (varus-valgus and anterior posterior). Both metrics have been evaluated using high level models and experimental measurement. Self-powered analog and digital architectures for the center of pressure are elaborated here and complies with the Medical Implant Communication Service (MICS) standard.

Self-powered instrumented knee implant for early detection of postoperative complications.

In-vivo measurement of tibiofemoral forces transmitted through Total Knee Replacement (TKR) during normal walking allows the early detection of postoperative complications such as the tibiofemoral misalignment and soft-tissue imbalance. In addition, the in-vivo data can help to improve the design of TKR in order to reduce polyethylene wear and consequently to increase the lifespan of knee implant. A self-powered custom-designed tibial implant instrumented with four piezoceramics has been developed in order to detect the aforementioned complications by measuring the relative change in pressure center (COP) position for different levels of eccentric compressive loading.

A self-powered telemetry system to estimate the postoperative instability of a knee implant.

Estimating in vivo the life span of a total knee replacement prosthesis is currently done by estimating the polyethylene (PE) wear rate from measurement of the femorotibial distance using X-ray photographies. This efficient method requires, however, waiting for few years to obtain a readout. This letter proposes using another metric that can be obtained within a couple of months of surgery, namely the center of pressure (COP).

Design and evaluation of instrumented smart knee implant.

The goal of ligament balancing in total knee arthroplasty (TKA) is to distribute the tibiofemoral compressive forces symmetrically between the medial and lateral compartments of a well-aligned prosthetic knee, as well as to reestablish a rectangular and identical tibiofemoral gap in both flexion and extension. Nowadays, the proper alignment of knee mechanical axis and the perfect equalization of flexion and extension gaps are ensured by computer-assisted TKA (CATKA). Nevertheless, any residual imbalance of collateral ligaments at the time of surgery can lead to an excessive imbalance in the postoperative period during the weight-bearing activities, which subject the knee collateral ligaments to increased loading.

Toward a dynamic approach of THA planning based on ultrasound.

The risk of dislocation after THA reportedly is minimized if the acetabular implant is oriented at 45 degrees inclination and 15 degrees anteversion with respect to the anterior pelvic plane. This reference plane now is used in computer-assisted protocols. However, this static approach may lead to postoperative instability because the dynamic variations of the pelvis influence effective cup orientation and are not taken into account in this approach.