40 documents found, page 1 of 4
Automatic assessment of Pectus Excavatum severity from CT images using deep lea...
Silva, Bruno André Pires; Pessanha, Inês; Correia-Pinto, Jorge; Fonseca, Jaime C.; Queirós, Sandro Filipe MonteiroPectus excavatum (PE) is the most common abnormality of the thoracic cage, whose severity is evaluated by extracting three indices (Haller, correction and asymmetry) from computed tomography (CT) images. To date, this analysis is performed manually, which is tedious and prone to variability. In this paper, a fully automatic framework for PE severity quantification from CT images is proposed, comprising three st...
Feasibility and accuracy of automated three-dimensional echocardiographic analy...
Morais, Pedro; Fan, Yiting; Queirós, Sandro Filipe Monteiro; D'hooge, Jan; Lee, Alex Pui-Wai; Vilaça, João LProcedural success of transcatheter left atrial appendage closure (LAAC) is dependent on correct device selection. Three-dimensional (3D) transesophageal echocardiography (TEE) is more accurate than the two-dimensional modality for evaluation of the complex anatomy of the left atrial appendage (LAA). However, 3D transesophageal echocardiographic analysis of the LAA is challenging and highly expertise dependent....
The impact of vendor-specific ultrasound beam-forming and processing techniques...
Papachristidis, Alexandros; Queirós, Sandro Filipe Monteiro; Theodoropoulos, Konstantinos C; D'hooge, Jan; Rafter, Patrick; Masoero, GiovanniMyocardial scar appears brighter compared with normal myocardium on echocardiography because of differences in tissue characteristics. The aim of this study was to test how different ultrasound pulse characteristics affect the brightness contrast (i.e., contrast ratio [CR]) between tissues of different acoustic properties, as well as the accuracy of assessing tissue volume.
Quality assurance of segmental strain values provided by commercial 2-D speckle...
Røsner, Assami; Alessandrini, Martino; Kjønås, Didrik; Mirea, Oana; Queirós, Sandro Filipe Monteiro; D'hooge, JanThe aim of this study was to determine the accuracy and reproducibility of vendor-specific regional strain values by echocardiography using in silico data. Synthetic 2-D ultrasound gray-scale images of the left ventricle (LV) were generated with knowledge of the longitudinal segmental strain values from the underlying electromechanical LV model. Four of five models mimicked transmural infarctions with systolic ...
Kidney segmentation in three-dimensional ultrasound images using a fast phase-b...
Torres, Helena R.; Queirós, Sandro Filipe Monteiro; Morais, Pedro André Gonçalves; Oliveira, Bruno; Fonseca, João Luís Gomes; Mota, PauloRenal ultrasound imaging is the primary imaging modality for the assessment of the kidney’s condition and is essential for diagnosis, treatment and surgical intervention planning, and follow-up. In this regard, kidney delineation in three-dimensional ultrasound images represents a relevant and challenging task in clinical practice. In this paper, a novel framework is proposed to accurately segment the kidney in...
Automated generation of synthetic in-car dataset for human body pose detection
Borges, João; Oliveira, Bruno; Torres, Helena Daniela Ribeiro; Rodrigues, Nelson; Queirós, Sandro Filipe Monteiro; Shiller, Maximilian; Coelho, VictorIn this paper, a toolchain for the generation of realistic synthetic images for human body pose detection in an in-car environment is proposed. The toolchain creates a customized synthetic environment, comprising human models, car, and camera. Poses are automatically generated for each human, taking into account a per-joint axis Gaussian distribution, constrained by anthropometric and range of motion measuremen...
Technical note: assessment of electromagnetic tracking systems in a surgical en...
Fonseca, João Luís Gomes; Veloso, Fernando; Queirós, Sandro Filipe Monteiro; Morais, Pedro André Gonçalves; Pinho, António C. M.; Fonseca, Jaime C.Purpose Electromagnetic tracking systems (EMTSs) have been proposed to assist the percutaneous renal access (PRA) during minimally invasive interventions to the renal system. However, the influence of other surgical instruments widely used during PRA (like ureteroscopy and ultrasound equipment) in the EMTS performance is not completely known. This work performs this assessment for two EMTSs [Aurora (R) Planar F...
Surface-based registration between CT and US for image-guided percutaneous rena...
Gomes-Fonseca, João; Queirós, Sandro Filipe Monteiro; Morais, Pedro; Pinho, António C. M.; Fonseca, Jaime C.; Correia-Pinto, JorgeAs a crucial step in accessing the kidney in several minimally invasive interventions, percutaneous renal access (PRA) practicality and safety may be improved through the fusion of computed tomography (CT) and ultrasound (US) data. This work aims to assess the potential of a surface-based registration technique and establish an optimal US acquisition protocol to fuse two-dimensional (2D) US and CT data for imag...
Three-dimensional color Doppler ultrasound simulation to mimic paravalvular reg...
Queirós, Sandro Filipe Monteiro; Gao, Hang; De Santis, Gianluca; Papachristidis, Alexandros; Fonseca, Jaime C.; Vilaça, João L.; D'hooge, JanDespite its high success rate, transcatheter aortic valve implantation (TAVI) is still associated with numerous complications, among which paravalvular regurgitation (PVR, which has been associated to long-term outcome. Assessment of PVR remains challenging in clinical routine; it lacks a solid reference method and the clinically used echocardiographic-based parameters have numerous limitations. Moreover, the d...
Semi-automatic aortic valve tract segmentation in 3D cardiac magnetic resonance...
Queirós, Sandro Filipe Monteiro; Morais, Pedro André Gonçalves; Fonseca, Jaime C.; D'hooge, Jan; Vilaça, João L.Accurate preoperative sizing of the aortic annulus (AoA) is crucial to determine the best fitting prosthesis to be implanted during transcatheter aortic valve (AV) implantation (TAVI). Although multidetector row computed tomography is currently the standard imaging modality for such assessment, 3D cardiac magnetic resonance (CMR) is a feasible radiation-free alternative. However, automatic AV segmentation and s...