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1.
Med Image Anal ; 90: 102956, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37713764

RESUMO

Screening colonoscopy is an important clinical application for several 3D computer vision techniques, including depth estimation, surface reconstruction, and missing region detection. However, the development, evaluation, and comparison of these techniques in real colonoscopy videos remain largely qualitative due to the difficulty of acquiring ground truth data. In this work, we present a Colonoscopy 3D Video Dataset (C3VD) acquired with a high definition clinical colonoscope and high-fidelity colon models for benchmarking computer vision methods in colonoscopy. We introduce a novel multimodal 2D-3D registration technique to register optical video sequences with ground truth rendered views of a known 3D model. The different modalities are registered by transforming optical images to depth maps with a Generative Adversarial Network and aligning edge features with an evolutionary optimizer. This registration method achieves an average translation error of 0.321 millimeters and an average rotation error of 0.159 degrees in simulation experiments where error-free ground truth is available. The method also leverages video information, improving registration accuracy by 55.6% for translation and 60.4% for rotation compared to single frame registration. 22 short video sequences were registered to generate 10,015 total frames with paired ground truth depth, surface normals, optical flow, occlusion, six degree-of-freedom pose, coverage maps, and 3D models. The dataset also includes screening videos acquired by a gastroenterologist with paired ground truth pose and 3D surface models. The dataset and registration source code are available at https://durr.jhu.edu/C3VD.

2.
Brachytherapy ; 21(3): 291-299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35623721

RESUMO

PURPOSE: To describe the development, design, and implementation of a 3D printed MR-compatible pediatric vaginal multichannel brachytherapy cylinder. Safety and quality measures to ensure consistent treatment required innovative identification on MR and CT, and real-time tracking. METHODS AND MATERIALS: A 4-year-old with vaginal botryoides rhabdomyosarcoma underwent MR-simulation with a custom 3D printed biocompatible resin cylinder with four channels to ensure dose optimization capability. A total of four identifier regions were designed into the applicator in order to utilize these for MR-visualization and real-time tracking. A biocompatible 3D printed cylinder was designed to meet dose objectives using an MR and CT compatible material. 3D slicer was required for real-time tracking during treatment. RESULTS: Based on MR simulation, a treatment plan was created with dose differentials in the area of prior surgery versus normal vaginal tissue. Creation of a low dose CT scan on a mobile CT allowed CT visualization of the applicator for verification. Treatment was administered under the use of a real-time optical tracking with rotational and depth adjustments monitored. CONCLUSIONS: This advanced integration of 3D printed MR and CT biocompatible material, with unique design features consistent with a multi-channel vaginal cylinder, and incorporation of real-time optical tracking ensured that no positional changes were required, allowed successful treatment with differential dosing for a post-operative pediatric vaginal rhabdomyosarcoma patient.


Assuntos
Braquiterapia , Rabdomiossarcoma Embrionário , Rabdomiossarcoma , Neoplasias Vaginais , Braquiterapia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Rabdomiossarcoma/diagnóstico por imagem , Rabdomiossarcoma/radioterapia , Vagina/diagnóstico por imagem , Neoplasias Vaginais/diagnóstico por imagem , Neoplasias Vaginais/radioterapia
3.
R Soc Open Sci ; 8(8): 210218, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34401194

RESUMO

Payments systems generate vast amounts of naturally occurring transaction data rarely used for constructing official statistics. We consider billions of transactions from card data from a large bank, Banco Bilbao Vizcaya Argentaria, as an alternative source of information for measuring consumption. We show, via validation against official consumption measures, that transaction data complements national accounts and consumption surveys. We then analyse the impact of COVID-19 in Spain, and document: (i) strong consumption responses to business closures, but smaller effects for capacity restrictions; (ii) a steeper decline in spending in rich neighbourhoods; (iii) higher mobility for residents of lower-income neighbourhoods, correlating with increased disease incidence.

4.
Mult Scler Relat Disord ; 42: 102072, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32330844

RESUMO

BACKGROUND: Cognitive impairment has been recognized as an important factor in multiple sclerosis (MS) in the past few years. One brief, reliable and valid tool to assess cognition in MS is the BICAMS, which encompasses the Symbol Digit Modalities Test (SDMT), the California Verbal Learning Test (CVLT II), and the Brief Visuospatial Memory Test - Revised (BVMT-R). Continuing with the international initiative to validate the BICAMS in different countries, here we present the results obtained from the efforts in validating such test in the Colombian population. METHOD: 100 healthy controls and 50 MS patients participated in the study, group matched for age, education and gender. Subjects completed all three tests of the BICAMS. Instead of the CVLT-II, the Colombian validated form PAMCL (Prueba de Aprendizaje y Memoria con Codificación Libre) was used. Test-retest measures were obtained for 16 patients in order to test for reliability. RESULTS: Evidence of criterion validity was obtained, MS group performing significantly worse than HC group in all three tests (SDMT: p= .001, d= 0.59; PAMCL: p= .03, d= 0.38; BVMT-R: p<.001, d= 0.58). Test-retest was also obtained, finding significant correlations for all three tests (SDMT: r=0.932, p<.00; BVMT-R: r=0.863, p<.001; PAMCL: r=0.889, p<.001). Standardization of raw scores to uncontrolled scaled scores was done and these scores were then adjusted for age and years of schooling using a multiple linear regression. CONCLUSIONS: The BICAMS proved to be a valid and sensitive tool to screen for cognitive impairment in MS patients.


Assuntos
Disfunção Cognitiva/diagnóstico , Esclerose Múltipla/diagnóstico , Testes Neuropsicológicos/normas , Adulto , Disfunção Cognitiva/etiologia , Colômbia , Feminino , Humanos , Masculino , Testes de Memória e Aprendizagem/normas , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Reprodutibilidade dos Testes , Adulto Jovem
5.
World J Pediatr Congenit Heart Surg ; 9(4): 454-458, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29945510

RESUMO

PURPOSE: Patients with hypoplastic left heart syndrome (HLHS) present a diverse spectrum of aortic arch morphology. Suboptimal geometry of the reconstructed aortic arch may result from inappropriate size and shape of an implanted patch and may be associated with poor outcomes. Meanwhile, advances in diagnostic imaging, computer-aided design, and three-dimensional (3D) printing technology have enabled the creation of 3D models. The purpose of this study is to create a surgical simulation and training model for aortic arch reconstruction. DESCRIPTION: Specialized segmentation software was used to isolate aortic arch anatomy from HLHS computed tomography scan images to create digital 3D models. Three-dimensional modeling software was used to modify the exported segmented models and digitally design printable customized patches that were optimally sized for arch reconstruction. EVALUATION: Life-sized models of HLHS aortic arch anatomy and a digitally derived customized patch were 3D printed to allow simulation of surgical suturing and reconstruction. The patient-specific customized patch was successfully used for surgical simulation. CONCLUSIONS: Feasibility of digital design and 3D printing of patient-specific patches for aortic arch reconstruction has been demonstrated. The technology facilitates surgical simulation. Surgical training that leads to an understanding of optimal aortic patch geometry is one element that may potentially influence outcomes for patients with HLHS.


Assuntos
Aorta Torácica/cirurgia , Procedimentos Cirúrgicos Cardíacos/educação , Desenho Assistido por Computador , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Modelos Anatômicos , Treinamento por Simulação/métodos , Aorta Torácica/anatomia & histologia , Aorta Torácica/diagnóstico por imagem , Procedimentos Cirúrgicos Cardíacos/métodos , Humanos , Impressão Tridimensional , Estudo de Prova de Conceito , Software , Tomografia Computadorizada por Raios X , Estados Unidos
6.
J Vasc Interv Neurol ; 10(1): 17-22, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29922399

RESUMO

OBJECTIVES: Virtual reality (VR) allows users to experience realistic, immersive 3D virtual environments with the depth perception and binocular field of view of real 3D settings. Newer VR technology has now allowed for interaction with 3D objects within these virtual environments through the use of VR controllers. This technical note describes our preliminary experience with VR as an adjunct tool to traditional angiographic imaging in the preprocedural workup of a patient with a complex pseudoaneurysm. METHODS: Angiographic MRI data was imported and segmented to create 3D meshes of bilateral carotid vasculature. The 3D meshes were then projected into VR space, allowing the operator to inspect the carotid vasculature using a 3D VR headset as well as interact with the pseudoaneurysm (handling, rotation, magnification, and sectioning) using two VR controllers. RESULTS: 3D segmentation of a complex pseudoaneurysm in the distal cervical segment of the right internal carotid artery was successfully performed and projected into VR. Conventional and VR visualization modes were equally effective in identifying and classifying the pathology. VR visualization allowed the operators to manipulate the dataset to achieve a greater understanding of the anatomy of the parent vessel, the angioarchitecture of the pseudoaneurysm, and the surface contours of all visualized structures. CONCLUSION: This preliminary study demonstrates the feasibility of utilizing VR for preprocedural evaluation in patients with anatomically complex neurovascular disorders. This novel visualization approach may serve as a valuable adjunct tool in deciding patient-specific treatment plans and selection of devices prior to intervention.

7.
Congenit Heart Dis ; 13(3): 357-361, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29399969

RESUMO

OBJECTIVE: New platforms for patient imaging present opportunities for improved surgical planning in complex congenital heart disease (CHD). Virtual reality (VR) allows for interactive manipulation of high-resolution representations of patient-specific imaging data, as a supplement to traditional 2D visualizations and 3D printed heart models. DESIGN: We present the novel use of VR for the presurgical planning of cardiac surgery in two infants with complex CHD to demonstrate interactive real-time views of complex intra and extracardiac anatomy. RESULTS: The use of VR for cardiac presurgical planning is feasible using existing imaging data. The software was evaluated by both pediatric cardiac surgeons and pediatric cardiologists, and felt to be reliable and operated with a very short learning curve. CONCLUSIONS: VR with controller-based interactive capability allows for interactive viewing of 3D models with complex intra and extracardiac anatomy. This serves as a useful complement to traditional preoperative planning methods in terms of its potential for group based collaborative discussion, user defined illustrative views, cost-effectiveness, and facility of use.


Assuntos
Cardiopatias Congênitas/diagnóstico , Imageamento Tridimensional , Modelos Anatômicos , Realidade Virtual , Humanos
8.
Mult Scler J Exp Transl Clin ; 4(1): 2055217317752202, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29372069

RESUMO

BACKGROUND: Multiple sclerosis is an inflammatory and neurodegenerative demyelinating disease. Current treatment of multiple sclerosis focuses on the use of immunomodulatory, immunosuppressant, and selective immunosuppressant agents. Some of these medications may result in high risk of opportunistic infections including tuberculosis. OBJECTIVE: The purpose of this study was to obtain consensus from a panel of neurologists, pulmonologists, infectious disease specialists, and epidemiology experts regarding the diagnosis, treatment, and monitoring of latent tuberculosis in patients with multiple sclerosis. METHODS: A panel of experts in multiple sclerosis and tuberculosis was established. The methodological process was performed in three phases: definition of questions, answer using Delphi methodology, and the discussion of questions not agreed. RESULTS: Tuberculosis screening is suggested when multiple sclerosis drugs are prescribed. The recommended tests for latent tuberculosis are tuberculin and interferon gamma release test. When an anti-tuberculosis treatment is indicated, monitoring should be performed to determine liver enzyme values with consideration of age as well as comorbid conditions such as a history of alcoholism, age, obesity, concomitant hepatotoxic drugs, and history of liver disease. CONCLUSION: Latent tuberculosis should be considered in patients with multiple sclerosis who are going to be treated with immunomodulatory and immunosuppressant medications. Transaminase level monitoring is required on a periodic basis depending on clinical and laboratory characteristics. In addition to the liver impairment, other side effects should be considered when Isoniazid is prescribed.

9.
J Oral Maxillofac Surg ; 75(7): 1491-1497, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28137637

RESUMO

Reconstructing auricular deformities for bilateral microtia is a demanding challenge especially after failed autologous reconstruction. This case report presents a novel application of virtual surgical planning, computer-assisted design, and intraoperative surgical navigation to preplan and execute placement of custom-tailored silicone auricular prostheses and titanium osseointegrated implants for a bone-anchored hearing aid system in a patient with Treacher Collins syndrome in whom autologous reconstruction had previously failed. Through a collaborative approach between the reconstructive surgeon and anaplastologist, the implementation of advanced digital technologies may offer a superior esthetic and functional outcome to patients with previously failed reconstruction.


Assuntos
Microtia Congênita/cirurgia , Cuidados Intraoperatórios/métodos , Procedimentos de Cirurgia Plástica/métodos , Impressão Tridimensional , Desenho de Prótese/métodos , Implantação de Prótese/métodos , Cirurgia Assistida por Computador , Adolescente , Microtia Congênita/patologia , Feminino , Humanos
10.
Ann Biomed Eng ; 45(1): 45-57, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27295184

RESUMO

The treatment of craniofacial defects can present many challenges due to the variety of tissue-specific requirements and the complexity of anatomical structures in that region. 3D-printing technologies provide clinicians, engineers and scientists with the ability to create patient-specific solutions for craniofacial defects. Currently, there are three key strategies that utilize these technologies to restore both appearance and function to patients: rehabilitation, reconstruction and regeneration. In rehabilitation, 3D-printing can be used to create prostheses to replace or cover damaged tissues. Reconstruction, through plastic surgery, can also leverage 3D-printing technologies to create custom cutting guides, fixation devices, practice models and implanted medical devices to improve patient outcomes. Regeneration of tissue attempts to replace defects with biological materials. 3D-printing can be used to create either scaffolds or living, cellular constructs to signal tissue-forming cells to regenerate defect regions. By integrating these three approaches, 3D-printing technologies afford the opportunity to develop personalized treatment plans and design-driven manufacturing solutions to improve aesthetic and functional outcomes for patients with craniofacial defects.


Assuntos
Regeneração Óssea , Ossos Faciais/lesões , Traumatismos Faciais , Procedimentos de Cirurgia Plástica/métodos , Engenharia Tecidual , Animais , Traumatismos Faciais/reabilitação , Traumatismos Faciais/cirurgia , Humanos , Impressão Tridimensional
11.
Acta Parasitol ; 61(4): 707-712, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27787214

RESUMO

The present study describes a new species of Trichodina found in the mucus of the body surface of 137 farmed and wild silver catfish (Rhamdia quelen) located in southern Brazil and in the gills of 99 banded knife fish (Gymnotus sp.) captured in the basin of Pantanal. Smears of the body surface mucus and gills were air dried at room temperature and impregnated with silver nitrate and stained with Giemsa for analysis of the adhesive disc, denticles and macronucleus. Characterized as a medium trichodinid, Trichodina quelenii n. sp. resembles T. heterodentata and T. acuta. It differs from T. heterodentata by the shape of the blade and from T. acuta by the lack of central circle. Furthermore, the distinct shape of the blade of T. quelenii n. sp. differs from all previously described species for the genus, leaving no doubt it is a new species.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/classificação , Doenças dos Peixes/parasitologia , Animais , Brasil/epidemiologia , Cilióforos/isolamento & purificação , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/epidemiologia , Peixes , Especificidade da Espécie
12.
Ann Plast Surg ; 72(6): 720-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24835867

RESUMO

INTRODUCTION: Current protocols for facial transplantation include the mandatory fabrication of an alloplastic "mask" to restore the congruency of the donor site in the setting of "open casket" burial. However, there is currently a paucity of literature describing the current state-of-the-art and available options. METHODS: During this study, we identified that most of donor masks are fabricated using conventional methods of impression, molds, silicone, and/or acrylic application by an experienced anaplastologist or maxillofacial prosthetics technician. However, with the recent introduction of several enhanced computer-assisted technologies, our facial transplant team hypothesized that there were areas for improvement with respect to cost and preparation time. RESULTS: The use of digital imaging for virtual surgical manipulation, computer-assisted planning, and prefabricated surgical cutting guides-in the setting of facial transplantation-provided us a novel opportunity for digital design and fabrication of a donor mask. The results shown here demonstrate an acceptable appearance for "open-casket" burial while maintaining donor identity after facial organ recovery. CONCLUSIONS: Several newer techniques for fabrication of facial transplant donor masks exist currently and are described within the article. These encompass digital impression, digital design, and additive manufacturing technology.


Assuntos
Transplante de Face , Máscaras , Procedimentos de Cirurgia Plástica/métodos , Desenho de Prótese , Aloenxertos Compostos/transplante , Desenho Assistido por Computador , Humanos , Processamento de Imagem Assistida por Computador , Elastômeros de Silicone , Tomografia Computadorizada por Raios X
14.
Arch Facial Plast Surg ; 11(1): 58-61, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19153295

RESUMO

Osseointegration implants have revolutionized craniofacial prosthetic reconstruction. Implant placement relies on adequate thickness and quality of bone to permit osseointegration. Positioning the implant is critical in craniofacial reconstruction because surface contours of the prosthesis must be preserved while housing attachment components securely and discretely. Also, the position of the final prosthesis must transition to native tissue smoothly. We report on the use of intraoperative stereotactic image guidance in the placement of implants for orbital, nasal, and auricular prosthetic reconstruction. Clinical data, intraoperative images, and postoperative rehabilitated results are presented to demonstrate the utility of the application of stereotactic image guidance for implant placement. In our experience, stereotactic image guidance facilitates optimal implant site selection if there is abnormal bone quantity or quality.


Assuntos
Materiais Biocompatíveis , Procedimentos de Cirurgia Plástica/métodos , Implantação de Prótese/métodos , Cirurgia Assistida por Computador , Titânio , Ferimentos e Lesões/cirurgia , Face , Humanos , Osseointegração , Estudos Prospectivos , Próteses e Implantes
16.
Arch Facial Plast Surg ; 9(5): 358-64, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17875830

RESUMO

We have sought strategies to enhance our ability to successfully reconstruct the human nose. We present one of our efforts to use current technology to improve our ability to accurately create the subsurface framework on which the success of such an endeavor rests. Our novel approach involves the creation of an intraoperative surgical guide, aided by 3-dimensional laser surface scanning and rapid prototyping. This translucent template is developed through cooperative effort by the patient, anaplastologist, and surgeon working together. It is then custom made, sterilized, and available for use during the procedure. It is placed on the patient's face at critical points during the procedure. The subsurface framework is then painstakingly built in a stable fashion to reflect the dimensions and contour of this guide. It is created in such a manner as to anticipate the effect of the thickness of the forehead flap on the final external dimensions.


Assuntos
Septo Nasal/patologia , Septo Nasal/cirurgia , Implantação de Prótese/métodos , Rinoplastia/métodos , Adulto , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Neoplasias Nasais/patologia , Neoplasias Nasais/cirurgia
17.
Clin Dysmorphol ; 15(3): 139-143, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16760731

RESUMO

In the present study we describe a patient with characteristic brachydactily, developmental delay and interstitial del 13q22-->q31. After the review of the literature, few cases sharing similar chromosomal deletions were found and they displayed little resemblance with our patient. We discuss the phenotype correlation among the deleted regions in such cases.


Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Cromossomos Humanos Par 13/genética , Fácies , Anormalidades Múltiplas/patologia , Criança , Bandeamento Cromossômico , Anormalidades Craniofaciais/patologia , Deformidades do Pé/patologia , Transtornos do Crescimento/patologia , Deformidades Congênitas da Mão/diagnóstico por imagem , Deformidades Congênitas da Mão/patologia , Humanos , Cariotipagem , Transtornos do Desenvolvimento da Linguagem/patologia , Masculino , Transtornos Psicomotores/patologia , Radiografia , Dedos do Pé/anormalidades , Dedos do Pé/diagnóstico por imagem
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