three dimensional reconstruction

BACKGROUND: Herein, we present a proof-of-concept study of 3-dimensional (3D) pouchography using virtual and printed 3D models of ileal pouch-anal anastomosis (IPAA) in patients with normal pouches and in cases of mechanical pouch complications. MATERIALS & METHODS: We performed a retrospective, descriptive case series of a convenience sample of 10 pouch patients with or without pouch dysfunction who had CT scans appropriate for segmentation were identified from our pouch registry...

Conventional B-mode ultrasound imaging has difficulty in delineating homogeneous soft tissues with similar acoustic impedances, as the reflectivity depends on the acoustic impedance at the interface. As a quantitative imaging biomarker sensitive to alteration of biomechanical properties, speed-of-sound (SoS) holds promising potential for tissue and disease differentiation such as delineation of different breast tissue types with similar acoustic impedance. Compared to two-dimensional (2D) SoS images, three-dimensional (3D) volumetric SoS images achieved through a full-angle ultrasound scan can reveal more intricate morphological structures of tissues; however, they generally require a ring transducer...

Deuterium metabolic imaging (DMI) is an emerging magnetic resonance technique, for non-invasive mapping of human brain glucose metabolism following oral or intravenous administration of deuterium-labeled glucose. Regional differences in glucose metabolism can be observed in various brain pathologies, such as Alzheimer's disease, cancer, epilepsy or schizophrenia, but the achievable spatial resolution of conventional phase-encoded DMI methods is limited due to prolonged acquisition times rendering submilliliter isotropic spatial resolution for dynamic whole brain DMI not feasible...

Genomic data collected from viral outbreaks can be exploited to reconstruct the dispersal history of viral lineages in a two-dimensional space using continuous phylogeographic inference. These spatially explicit reconstructions can subsequently be used to estimate dispersal metrics allowing to unveil the dispersal dynamics and evaluate the capacity to spread among hosts. Heterogeneous sampling intensity of genomic sequences can however impact the accuracy of dispersal insights gained through phylogeographic inference...

The cigarette filter is an essential component of modern cigarettes and studying the flow distribution within the cigarette filter is of great significance in reducing the harm of cigarettes and optimizing smoking sensations. As the object of numerical simulation research, a three-dimensional model of the cigarette was accurately constructed through micro-CT reverse engineering, achieving a scanning accuracy of 4.05 μm. An overall porous media model of the cigarette filter was established to characterize the pressure distribution inside the filter...

Tucker decomposition is widely used for image representation, data reconstruction, and machine learning tasks, but the calculation cost for updating the Tucker core is high. Bilevel form of triple decomposition (TriD) overcomes this issue by decomposing the Tucker core into three low-dimensional third-order factor tensors and plays an important role in the dimension reduction of data representation. TriD, on the other hand, is incapable of precisely encoding similarity relationships for tensor data with a complex manifold structure...

Cancer models play critical roles in basic cancer research and precision medicine. However, current in vitro cancer models are limited by their inability to mimic the three-dimensional architecture and heterogeneous tumor microenvironments (TME) of in vivo tumors. Here, we develop an innovative patient-specific lung cancer assembloid (LCA) model by using droplet microfluidic technology based on a microinjection strategy. This method enables precise manipulation of clinical microsamples and rapid generation of LCAs with good intra-batch consistency in size and cell composition by evenly encapsulating patient tumor-derived TME cells and lung cancer organoids inside microgels...

Bilateral Wilms tumour (BWT) is a surgically challenging condition. Virtual reality (VR) reconstruction aids surgeons to foresee the anatomy ahead of Nephron Sparing Surgery (NSS). Three-dimensional (3D) visualisation improves the anatomical orientation of surgeons performing NSS. We herewith report a case of BWT where VR planning and 3D printing were used to aid NSS. Conventional imaging is often found to be inadequate while assessing the tumour-organ-vascular anatomy. Advances like VR and 3D printing help surgeons plan better for complex surgeries like bilateral NSS...

BACKGROUND: In patients with traumatic posterior shoulder instability, little is known about the precise location and size of the reverse Hill-Sachs lesion. METHODS: Forty-nine shoulders of 47 patients with traumatic posterior instability were included in this study based on the following inclusion criteria: 1) a primary or recurrent traumatic posterior shoulder dislocation, and 2) the initial event was caused by trauma. Patients were excluded if they had: 1) no history of trauma, 2) prior shoulder surgery, 3) no CT examination, or 4) seizure cases...

Dose conformity is an essential parameter used in radiotherapy and radiosurgery that measures the correspondence of the dose distribution derived from a Treatment Planning System (TPS) with the actual volume to be treated, the Planning Treatment Volume (PTV). The present work uses a method based on the expansion of dose distributions and PTVs by three-dimensional Zernike polynomials and further comparison of their moments to define a general criterion of dose conformity. To carry on this study, data coming from 20 patients comprising 80 datasets exported from the TPS, which included imaging data (PTVs) and dose distributions corresponding to different treatment modalities: three-dimensional conformal radiotherapy, intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT), were used...

BACKGROUND: In recent years, the medical community has witnessed a notable increase in high-energy traumatic injuries, leading to a surge in complex fracture patterns that challenge existing treatment methodologies. Among these, the posterior approach to acetabular fractures stands out for offering direct visualization of the retro-acetabular surface, with current fixation methods relying on 3.5 mm low-profile reconstruction plates and various other implants. Despite the effectiveness of these methods, there is a burgeoning demand for a singular, adaptable implant that not only streamlines the surgical process but also optimizes patient outcomes...

The plantar aponeurosis (PA) is an elastic longitudinal band that contributes to the generation of a propulsive force in the push-off phase during walking and running through the windlass mechanism. However, the dynamic behavior of the PA remains unclear owing to the lack of direct measurement of the strain it generates. Therefore, this study aimed to visualize and quantify the PA behavior during two distinct foot postures: (i) neutral posture and (ii) windlass posture with midtarsal joint plantarflexion and metatarsophalangeal joint dorsiflexion, using computed tomography scans...

To better understand molecular aspects of equine endometrial function, there is a need for advanced in vitro culture systems that more closely imitate the intricate 3-dimensional (3D) in vivo endometrial structure than current techniques. However, development of a 3D in vitro model of this complex tissue is challenging. This study aimed to develop an in vitro 3D endometrial tissue (3D-ET) with an epithelial cell phenotype optimized by treatment with a Rho-associated protein kinase (ROCK) inhibitor. Equine endometrial epithelial (eECs) and mesenchymal stromal (eMSCs) cells were isolated separately, and eECs cultured in various concentrations of Rock inhibitor (0, 5, 10 µmol) in epithelial medium (EC-medium) containing 10% knock-out serum replacement (KSR)...

Modern medical imaging plays a vital role in clinical practice, enabling non-invasive visualization of anatomical structures. Dynamic contrast enhancement (DCE) imaging is a technique that uses contrast agents to visualize blood flow dynamics in a time-resolved manner. It can be applied to different modalities, such as computed tomography (CT) and electrical impedance tomography (EIT). This study aims to develop a common theoretical and practical hemodynamic extraction basis for DCE modelling across modalities, based on the gamma-variate function...

RATIONALE: The conventional treatment of giant cell tumors is intralesional curettage with local adjuvant therapy. Because hand tumors have a high local recurrence, the primary goal for treating tumors of the hand is to eradicate the lesion. PATIENT CONCERNS: To preserve the metacarpophalangeal (MCP) joint function as well as avoid further recurrence after surgery. DIAGNOSES: The giant cell tumor invades the patient's MCP joint in an index proximal phalanx...

This paper presents a novel method based on leveraging physics-informed neural networks for magnetic resonance electrical property tomography (MREPT). MREPT is a noninvasive technique that can retrieve the spatial distribution of electrical properties (EPs) of scanned tissues from measured transmit radiofrequency (RF) in magnetic resonance imaging (MRI) systems. The reconstruction of EP values in MREPT is achieved by solving a partial differential equation derived from Maxwell's equations that lacks a direct solution...

The use of head-mounted augmented reality (AR) for surgeries has grown rapidly in recent years. AR aids in intraoperative surgical navigation through overlaying three-dimensional (3D) holographic reconstructions of medical data. However, performing AR surgeries on complex areas such as the head and neck region poses challenges in terms of accuracy and speed. This study explores the feasibility of an AR guidance system for resections of positive tumour margins in a cadaveric specimen. The authors present an intraoperative solution that enables surgeons to upload and visualize holographic reconstructions of resected cadaver tissues...

Standard models for perfusion quantification in DCE-MRI produce a bias by treating voxels as isolated systems. Spatiotemporal models can remove this bias, but it is unknown whether they are fundamentally identifiable. The aim of this study is to investigate this question in-silico using one-dimensional toy systems with a one-compartment blood flow model and a two-compartment perfusion model.

Approach: For each of the two models, identifiability is explored theoretically and in-silico for three systems...

OBJECTIVE: Pharmacokinetic parametric images obtained through dynamic fluorescence molecular tomography (DFMT) has ability of capturing dynamic changes in fluorescence concentration, thereby providing three-dimensional metabolic information for applications in biological research and drug development. However, data processing of DFMT is time-consuming, involves a vast amount of data, and the problem itself is ill-posed, which significantly limits the application of pharmacokinetic parametric images reconstruction...

PURPOSE: The preserved head of King Henri IV of France (life 1553-1610, reign 1589-1610) has survived to the present day thanks to high-quality embalming and favorable conservation conditions. The aim of this study was to examine Henry IV's upper resonant cavities and mastoids using an original and innovative forensic three-dimensional segmentation method. METHODS: The paranasal sinuses and mastoid cells of King Henri IV of France were studied by cross-referencing available biographical information with clinical and flexible endoscopic examination and computed tomography (CT-scan) imaging...