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1.
Sensors (Basel) ; 24(19)2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39409410

ABSTRACT

This paper presents a prototype of a portable and modular electrical impedance tomography (EIT) system for breast tumor detection. The proposed system uses MATLAB to generate three-dimensional representations of breast tissue. The modular architecture of the system allows for flexible customization and scalability. It consists of several interconnected modules. Each module can be easily replaced or upgraded, facilitating system maintenance and future enhancements. Testing of the prototype has shown promising results in preliminary screening based on experimental studies. Agar models were used for the experimental stage of this project. The 3D representations provide clinicians with valuable information for accurate diagnosis and treatment planning. Further research and refinement of the system is warranted to validate its performance in future clinical trials.


Subject(s)
Breast Neoplasms , Electric Impedance , Imaging, Three-Dimensional , Tomography , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/diagnosis , Humans , Tomography/instrumentation , Tomography/methods , Female , Imaging, Three-Dimensional/methods , Equipment Design
2.
In. García Cartaya, Pedro; Breijo García, Carlos Manuel; García Jordá, Pedro Alberto. Tomografía computarizada. Alta tecnología en imágenes médicas. La Habana, Editorial Ciencias Médicas, 2020. , ilus.
Monography in Spanish | CUMED | ID: cum-76318
4.
Biomed Phys Eng Express ; 6(4): 045008, 2020 05 14.
Article in English | MEDLINE | ID: mdl-33444269

ABSTRACT

Bioimpedance measurements are currently used to monitor various biological processes and are potentially useful for studies of urodynamics. Global impedance (GI) and focused impedance measurements (FIM) can be used to monitor bladder volumes, but these are subject to varying conductivity of urine. To address this, we emulated a human bladder using an agar phantom filled with saline solutions of varying conductivities and estimated volumes using a modified FIM-based approach. Using this novel strategy, electrical potentials did not change significantly with constant liquid volumes, even when the conductivity of the saline solutions was varied between 1.027 to 1.877 and 2.610 S/m. Conversely, GI and classic FIM measurements of constant liquid volumes varied with conductivity. These observations suggest that the proposed FIM approach is suitable for bladder volume estimation due to its robustness against uncertainties of conductivity. The bioimpedance hardware used in our experiments comprised 8 electrodes and a a small and low cost impedance measurement system based on an AFE4300 direct impedance measurement device.


Subject(s)
Electric Conductivity , Electric Impedance , Tomography/instrumentation , Urinary Bladder/pathology , Urine/chemistry , Urodynamics , Computer Simulation , Electrodes , Humans , Phantoms, Imaging , Uncertainty
5.
Rev. mex. cardiol ; 29(1): 45-49, Jan.-Mar. 2018. graf
Article in English | LILACS | ID: biblio-1004300

ABSTRACT

Abstract: Primary cardiac tumors in adults are rare and mostly benign, approximately 75%, being the myxoma the most frequent in half of that percentage. One-fourth of the primary cardiac tumors are malignant and 95% of the cases are sarcomas. Metastases are more frequent than primary tumors. Cardiac surgery is indicated specially in benign masses and therapies such as chemotherapy and/or radiotherapy should be reserved for unresectable or metastatic malignancies. Hence the importance of a diagnostic approach, which leads to the best therapeutic conduct and in many cases, a multimodal image approach is necessary, as it is exposed in our case.(AU)


Resumen: Los tumores cardiacos primarios en adultos son raros y en su mayoría benignos, aproximadamente el 75%, siendo el mixoma el más frecuente en la mitad de ese porcentaje. Un cuarto de los tumores cardiacos primarios son malignos y el 95% de los casos son sarcomas. Las metástasis son más frecuentes que los tumores primarios. La cirugía cardiaca está indicada especialmente en masas benignas y las terapias como la quimioterapia y/o la radioterapia deben reservarse para tumores malignos o metástasis irresecables. De ahí la importancia de un enfoque de diagnóstico, que conduzca a la mejor conducta terapéutica y, en muchos casos, es necesario un enfoque de imagen multimodal, como está expuesto en nuestro caso.(AU)


Subject(s)
Humans , Foramen Ovale/physiopathology , Myxoma/diagnostic imaging , Magnetic Resonance Imaging/instrumentation , Echocardiography/instrumentation , Tomography/instrumentation , Multimodal Imaging/methods
6.
Full dent. sci ; 9(34): 11-18, 2018. ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-987594

ABSTRACT

A readequação de rebordos alveolares que apresentam defeitos verticais representa um grande desafio aos profissionais da Implantodontia. Visando contornar tais desafios, o avanço das tecnologias permite a utilização de malhas de titânio customizadas, cujo processo de fabricação é baseado na tomografia do paciente a que se destina tal malha, sendo produzida de forma específica para corrigir o defeito daquele paciente. Nesse sentido, este trabalho apresenta um caso clínico que demonstra o protocolo cirúrgico que nosso grupo adota para reconstruir os defeitos verticais dos rebordos alveolares, utilizando malha de titânio customizada associada a rhBMP-2 e biomateriais (AU).


The re-adaptation of alveolar ridges that present vertical defects poses a great challenge to Implantology professionals. In order to overcome these challenges, the advancement of technologies allows the use of custom titanium meshes, whose manufacturing process is based on the tomography of the patient to which this mesh is destined to, being produced in a specific way to correct the defect of that patient. So this work presents a clinical case that demonstrates the surgical protocol that our group adopts to reconstruct the vertical defects of the alveolar rims, using custom titanium mesh associated with rhBMP-2 and biomaterials (AU).


Subject(s)
Humans , Female , Middle Aged , Titanium , Biocompatible Materials , Dental Implants , Bone Transplantation/methods , Mandibular Reconstruction , Surgical Procedures, Operative , Brazil , Tomography/instrumentation , Dental Prosthesis Design , Alveolar Process
7.
Full dent. sci ; 9(35): 11-16, 2018. ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-988317

ABSTRACT

A realização de cirurgia de levantamento do soalho do seio maxilar (LSSM) nos pacientes que apresentam septo sinusal, sem que ocorra perfuração da membrana sinusal, representa um verdadeiro desafio aos profissionais da Implantodontia. Sendo assim, este artigo relata um caso clínico de cirurgia de LSSM em paciente que possuía septo no seio maxilar. Procurou-se evidenciar os principais cuidados que devem ser tomados na abordagem cirúrgica, bem como as formas de tratamento para as eventuais intercorrências (AU).


The performance of maxillary sinus floor surgery (MSFS) in patients with sinus septum without perforation of sinus membrane poses a real challenge to the professionals of Implant Dentistry. Thus, this article reports a clinical case of MSFS in a patient with septum in the maxillary sinus. The main objective was to highlight the main care that should be taken in the surgical approach, as well as kind of treatments for possible complications (AU).


Subject(s)
Humans , Female , Middle Aged , Postoperative Complications , Bone Transplantation/methods , Maxillary Sinus/surgery , Mouth Floor , Osteotomy , Surgical Procedures, Operative , Brazil , Radiography, Dental/instrumentation , Tomography/instrumentation
8.
Full dent. sci ; 8(32): 27-32, 2017. tab, ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-915202

ABSTRACT

A extração do terceiro molar é um procedimento comum dentro da área cirúrgica da odontologia e, como todo procedimento dessa natureza, está sujeito a intercorrências e complicações como hemorragias, trismo e infecções. Os abscessos de origem odontogênica são casos comumente encontrados nos atendimentos de urgências odontológicas e quando bem tratados geralmente evoluem com melhora do quadro, porém essa infecção pode evoluir com disseminação para espaços faciais e cervicais, acarretando piora do quadro e podendo levar o paciente a óbito. O objetivo desse relato é descrever um caso clínico de abscesso retrofaríngeo, por origem de foco odontogênico, ressaltando suas particularidades e a importância do diagnóstico precoce para controle e resolução do caso. Conclui-se que é importante uma rápida intervenção e acompanhamento multidisciplinar em um serviço de referência estruturado e capaz de fazer evoluir o caso com suporte e segurança (AU).


Third molar extractions are frequent procedures within the surgical area of dentistry and, like any procedure of this nature, these extractions are susceptible to intercurrences and complications such as hemorrhages, trismus and infections. Abscesses of odontogenic origin are common in dental emergency services. When well treated, they usually evolve with improvement of the condition, but these infections can also evolve with dissemination to facial and cervical spaces, leading to condition worsening and even death. The objective of this report is to describe a clinical case of a retropharyngeal abscess of odontogenic origin, highlighting its particularities and the importance of early diagnosis for the control and resolution of the case. It was concluded that a rapid intervention and multidisciplinary follow-up is important in a structured reference service capable of evolving the case with support and security (AU).


Subject(s)
Humans , Female , Adult , Surgical Procedures, Operative , Tooth Extraction , Tooth, Unerupted/anatomy & histology , Retropharyngeal Abscess , Focal Infection, Dental , Molar, Third , Brazil , Tomography/instrumentation , Early Diagnosis
9.
Full dent. sci ; 9(33): 30-37, 2017. ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-981897

ABSTRACT

A APR-F é uma nova geração de agregados plaquetários obtida através da coleta de sangue do próprio paciente, e atua nos processos essenciais de reparação tecidual. É constituída por uma malha tridimensional de fibrina autóloga obtida a partir da centrifugação controlada do sangue. A liberação de fatores de crescimento ajuda a restabelecer a estrutura óssea perdida. A apicectomia tem como finalidade resolver problemas que não puderam ser solucionados pelo tratamento endodôntico convencional, ou quando este não é possível, em casos de lesões periapicais persistentes, ou ainda com características císticas, canais radiculares calcificados com lesões periapicais onde é inviável o acesso via câmara pulpar, instrumentos fraturados, perfurações apicais e degraus. O presente artigo relata o caso clínico de uma paciente com lesão no ápice do incisivo central superior esquerdo devido ao extravasamento do material obturador, onde foi realizado procedimento cirúrgico de apicectomia e, em seguida, utilizada fibrina autóloga (A-PRF) com intuito de otimizar a reparação óssea e acelerar o processo de cicatrização. Com base na literatura e no resultado obtido neste trabalho, concluiu-se que a realização da apicectomia associada à A-PRF pode ser considerada uma alternativa promissora (AU).


APR-F is a new generation of platelet aggregates obtained through patient blood collection and it acts in the essential processes of tissue repair. It consists of a three-dimensional autologous fibrin mesh obtained from controlled centrifugation of blood. The release of growth factors helps to restore the lost bone structure. The aim of apicectomy is to solve problems that could not be solved by conventional endodontic treatment, or when this is not possible, in cases of persistent periapical lesions or cystic features, calcified root canals with periapical lesions in which pulp chamber access is not feasible, fractured instruments, apical perforations and steps. This article reports the clinical case of a patient with lesion at the apex of the left upper central incisor due to extravasation of the obturator material, where surgical procedure of apicectomy was performed and then autologous fibrin (A-PRF) was used in order to optimize bone repair and accelerate the healing process. Based on the literature and the result obtained in this study, it can be concluded that the apicectomy associated with APRF can be considered a promising alternative (AU).


Subject(s)
Humans , Female , Middle Aged , Apicoectomy/methods , Blood , Bone Regeneration , Case Reports , Fibrin Tissue Adhesive , Osteotomy , Surgical Procedures, Operative/methods , Wound Healing , Brazil , Tomography/instrumentation , Incisor
10.
Rev. méd. (La Paz) ; 22(1): 47-54, 2016. ilus
Article in Spanish | LILACS | ID: lil-797315

ABSTRACT

El objetivo del presente caso clínico es mostrar los signos y síntomas que puedan determinar diagnósticos presuntivos no claros, cuándo se trata de masas mesentéricas primarias, que pueden simular patologías de origen biliar, compromiso vascular mesentérico, síndromes de FID y patologías ginecológicas dependientes de anexo derecho. La TAC es el patrón diagnóstico, que no cuentan los hospitales de segundo nivel como el nuestro, de manera que las decisiones que se toman en el servicio de emergencias, frente a este tipo de abdomen agudo quirúrgico es una laparotomía exploradora; para evitar complicaciones, no solo en órganos de la cavidad abdominal, sino también de orden legal. Los resultados de la cirugía mostraron la presencia de un masa mesentérica correspondiente a un absceso mesentérico inespecífico compatible con una paniculitis intra-abdominal, patología rara dentro la estadística nacional e internacional. Los síntomas más frecuentes son dolor abdominal, anorexia, plenitud abdominal y pérdida de peso, a veces oclusión intestinal. Otras manifestaciones comprenden: estreñimiento, fiebre, diarrea y a la palpación; masa abdominal. La duración de los síntomas es mayor a dos semanas. El laboratorio a veces es normal con aumento del VES. El contraste baritado muestra la pared del colon de aspecto irregular sin lesiones intraluminales. La ecografía; masa hiperecogenica bien definida en la raíz. La TAC: aumento de la densidad grasa, del mesenterio, bien delimitada con halo graso o pseudocapsula que rodea a los ganglios y vasos (signo del anillo graso fat-ring sign).


The present study aims to display how the patient symptomatology does not help to determine a clear presuntive diagnoses, especially when we deal with primary mesenteric masses that can simulate a biliary pathology, mesenteric vascular disorder, right lower quadrant syndrome and dependent gynecological pathologies of right annex. CT is a diagnostic pattern that second level hospitals do not have, so that decisions are taken into the emergency room. An exploratory laparatomy is the option to face up such acute abdomen in order to avoid complications in organs of abdominal cavity as well as legal problems. This case report, surgery results displayed the presence of a mesenteric mass corresponding to a non-specific mesenteric abscess compatible with a intra-abdominal panniculitis, an unusual pathology according to national and international statistics data. The most frecuent symptoms are abdominal pain, anorexia, abdominal fullness, loss of weight and sometimes intestinal occlusion. Constipation, fever, diarrhea and abdominal tenderness are additional manifestations. Those symptoms last longer than two weeks. Laboratory results display normal but with an increased ESR. Barium test shows a colon wall of irregular appearance without intraluminal injury. Ultrasound shows a hyperechoic mass well defined in the root. CT reflects an increased density of the mesenteric fat, well defined with a pseudocapsule that rounds lymph nodes and vessels (fat-ring sign).


Subject(s)
Humans , Female , Adult , Panniculitis, Peritoneal , Mesentery/abnormalities , Tomography/instrumentation , Abdominal Pain/diagnosis
11.
Rev. bras. oftalmol ; 74(6): 382-385, nov.-dez. 2015. tab, graf
Article in English | LILACS | ID: lil-767083

ABSTRACT

RESUMO Objetivo: Avaliar a capacidade de dados de perfil paquimétrico horizontal, a fim de distinguir o ceratocone de córneas normais, e comparar a precisão de índices com outros tomográficos mais complexos. Métodos: Em um estudo retrospectivo, um olho selecionado aleatoriamente de 225 pacientes com ceratocone bilateral e de 335 pacientes com córneas normais foram incluídos. Todos os pacientes foram examinados por um especialista em córnea e foram submetidos ao exame de tomografia de córnea, Pentacam HR (Oculus, Wetzlar, Alemanha). Os dados de perfil paquimétrico horizontal em 6 milímetros passando pelo ápice foi avaliado. Com esses dados, a espessura no ápice corneano (P.ápice), a espessura no ponto mais fino do perfil horizontal (P.min.H), a progressão paquimétrica do ponto mais fino para o mais espesso (PPmin-máx), a progressão paquimétrica média no meridiano temos como referencial a média normal (PPméd) e a adequação a uma linha de tendência polinomial do segundo grau (R2). Um modelo de inteligência artificial foi construído para combinar esses dados. O desempenho para distinguir ceratocone do normal foi avaliada por curvas ROC. Resultados: Todos os índices avaliados foram estatisticamente diferentes entre os dois grupos (p <0,001). A área sob a curva ROC (AUC) de paquimetria no ápice e no TP foram de 0,904 e 0,938, respectivamente. O índice tomográfico com maior AUC foi o BAD-D (0,997). Em relação ao perfil horizontal, a AUC do P.min.H e PPmin-max foram 0,915 e 0,927, respectivamente. A adequação à linha de tendência para o gráfico de espessura no ápice apresentou AUC 0,896. O melhor desempenho foi obtido com o PPméd (AUC 0,932 Sensibilidade = 84,4% e especificidade de 92,5%). O modelo de inteligência artificial combinando todos os itens derivados do perfil horizontal melhorou o desempenho (AUC 0,991 Sens. = 96% e espec. = 98%). Conclusão: O perfil de espessura horizontal permite detectar o ceratocone, com capacidade comparável aos índices mais complexos. Esse tipo de análise pode fornecer o básico para novas abordagens, que utilizem dados presentes em aparelhos mais simples que o tomógrafo, reduzindo o custo para os pacientes.


ABSTRACT Purpose: To evaluate the ability of horizontal thickness profile to distinguish keratoconus from normal corneas, and compare the accuracy of these indices with more complex tomographic indices. Methods: In a retrospective study, one eye randomly selected from 225 patients with bilateral keratoconus and 335 patients with normal corneas were included. All patients were examined by a corneal specialist and underwent the examination of corneal tomography, Pentacam HR (Oculus, Wetzlar, Germany). Data of horizontal pachymetric profile passing through the apex of 6 mm was evaluated. With these data, the thickness at the corneal apex (P.ápice), the thickness of the thinnest point of the horizontal profile (P.min.H), the pachymetric progression from the thinnest point to the thickest (PPmin-max), the average pachymetric progression in the meridian as reference the average from the normal population (PPméd) and the fitness with a second degree polynomial trendline (R2). An artificial intelligence model was built to combine this data. The performance for distinguishing normal keratoconus was evaluated by ROC curves. Results: All of these indices were statistically different between the two groups (p <0.001). The area under the ROC curve (AUC) thickness at the apex and TP were 0.904 and 0.938, respectively. The tomographic index with higher AUC was BAD-D (0.997). Regarding the horizontal profile, the AUC of PP.min.H and PPmin-max were 0.915 and 0.927, respectively. The fitness to the trendline to the horizontal thickness graph AUC was 0.896. The best performance was obtained with the PPméd (AUC 0.932 sensitivity = 84.4% and specificity of 92.5%). The artificial intelligence model combining all items derived from horizontal profile improved performance (AUC 0.991 Sensitivity = 96% and specificity of 98%). Conclusion: The horizontal thickness profile can detect keratoconus, with a capacity comparable to more complex indices. This type of analysis can provide the basics for new approaches, using data present in simpler devices than the tomographer reducing the cost for the patients.


Subject(s)
Humans , Adult , Tomography/methods , Corneal Topography/methods , Corneal Pachymetry/methods , Keratoconus/diagnosis , Tomography/instrumentation , Retrospective Studies , Cornea/anatomy & histology , Cornea/diagnostic imaging , Corneal Topography/instrumentation , Corneal Pachymetry/instrumentation
12.
São Paulo; s.n; 2015. 56 p. ilus, tab. (BR).
Thesis in Portuguese | LILACS, BBO - Dentistry | ID: biblio-867919

ABSTRACT

Alterações na articulação emporomandibular (ATM) comumente geram desequilíbrios musculares que estão associados à alterações no tecido ósseo. Esta articulação pode sofrer a influência de traumas, fatores congênitos ou desordens de crescimento. Estudos sobre alterações de crescimento do complexo maxilomandibular decorrentes de problemas da ATM são escassos. O objetivo deste trabalho foi avaliar por meio da microtomografia os efeitos da remoção do disco articular e a remoção conjugada do disco e cartilagem articular no crescimento e na microarquitetura óssea da mandíbula de ratos. Trinta ratos da raça Wistar com um mês de idade foram divididos em três grupos: CTR (controle operado); RD (remoção de disco articular) e RDC (remoção conjugada do disco e cartilagem articular). Apenas o lado direito foi operado; o lado esquerdo permaneceu intacto. Após dois meses de acompanhamento, os ratos foram sacrificados e as hemimandíbulas escaneadas em microtomógrafo A remoção do disco articular e a remoção conjugada do disco e cartilagem articular alteram o volume e microestrutura do osso trabecular da mandíbula de ratos jovens. Estas duas intervenções provocaram uma queda na qualidade de parâmetros da microestrutura do trabeculado do processo angular e diminuição do crescimento da hemimandíbula do lado operado.


Changes in the temporomandibular joint (TMJ) lead to muscle dysfunctions that are associated with bone changes. This joint region can be influenced by trauma, congenital factors or growth disorders. Studies linking TMJ problems and growth alterations are scarce. The aim of this study was to evaluate the effects of the articular disc removal or articular disc and cartilage removal on the bone microarchitecture and mandibular growth of young rats. Thirty Wistar rats (one month old) were divided into three groups: CTR (sham operated); RD (disc removal) and RDC (disc and cartilage removal). Only the right side was operated, keeping the left side intact. After two months, the rats were sacrificed and the mandibles scanned on micro-CT for quantitative analysis. Some microstructural parameters were altered by the disc removal or disc and cartilage removal. The right side presented lower growth than the left side.


Subject(s)
Humans , Male , Female , Temporomandibular Joint/abnormalities , Temporomandibular Joint/growth & development , Temporomandibular Joint/injuries , Temporomandibular Joint/metabolism , Cartilage, Articular/growth & development , Growth and Development , Tomography/adverse effects , Tomography/instrumentation , Tomography/methods
13.
Iatreia ; Iatreia;26(4): 476-480, oct.-dic. 2013. ilus
Article in Spanish | LILACS | ID: lil-695817

ABSTRACT

Se informa el caso de un hombre residente en la ciudad de Bogotá, Colombia, quien consultó al servicio de urgencias del Hospital el Tunal de dicha ciudad por dolor abdominal progresivo de seis días de evolución, localizado en el cuadrante superior derecho, asociado a ictericia y fiebre, sin antecedentes relevantes. Al ingreso tenía deterioro marcado del estado general, por lo que requirió atención en la unidad de cuidados intesivos; se le hicieron estudios de imágenes diagnósticas que documentaron una colección multiseptada en el lóbulo hepático izquierdo, y un cuerpo extraño. En la laparotomía se encontró un hueso de pescado como causa del absceso. Con el drenaje y la terapia antibiótica la evolución fue favorable.


We report the case of a man who consulted the emergency department of Hospital el Tunal in Bogotá, Colombia, because of six days of progressive abdominal pain in the upper right quadrant, associated with jaundice and fever; there was no relevant information in his medical history. On admission he was found in poor general condition and required management in the intensive care unit; diagnostic imaging studies documented a multiseptate collection in the left hepatic lobe, and a foreign body. He was submitted to laparotomy in which a fish bone was found as the cause of the abscess. After drainage of the collection and with antibiotic therapy evolution was favorable.


Subject(s)
Humans , Liver Abscess/diagnosis , Liver Abscess/etiology , Foreign Bodies/complications , Tomography/instrumentation
14.
Rev. bras. oftalmol ; 71(1): 8-13, jan.-fev. 2012. graf, tab
Article in Portuguese | LILACS | ID: lil-618311

ABSTRACT

OBJETIVO: Comparar discos ópticos de pacientes normais com história familiar de glaucoma primário de ângulo aberto (GPAA) com um grupo controle sem histórico familiar de glaucoma através da oftalmoscopia confocal a laser (HRTII). MÉTODOS: Análise retrospectiva da morfometria dos discos ópticos de pacientes com e sem história familiar de GPAA. Cada paciente foi submetido a exame oftalmológico completo, perimetria computadorizada, paquimetria e HRTII. Os pacientes foram classificados em três grupos de acordo com o grau de parentesco: primeiro grau (grupo 1), segundo grau (grupo 2) e grupo controle sem história familiar de glaucoma (grupo 3). Foram analisados: área total do disco óptico (Área Total), área de faixa neural (FxN), área da escavação (Esc.), relação escavação/disco (E/D) e relação E/D linear (L). Para a análise estatística, utilizou-se o programa SPSS 12.0. considerando-se apenas um dos olhos de cada paciente selecionado aleatoriamente. RESULTADOS: Foram incluídos setenta e quatro pacientes com idade média de 42,58 anos. Comparando-se os grupos 1 e 2, encontrou-se diferença estatisticamente significativa na variável Área Total, observando-se discos ópticos maiores no grupo 1. Comparando-se os grupos 1 e 3, as diferenças entre as variáveis Área Total, Esc, E/D e L foram estatisticamente significativas com predominância de valores mais elevados no grupo 1. Comparando-se os dados estereométricos entre os grupos 2 e 3 não foram encontradas diferenças de valores estatisticamente significantes. CONCLUSÃO: Pacientes normais parentes de primeiro grau de glaucomatosos apresentam maiores valores das variáveis topográficas do disco óptico quando comparados aos dos pacientes sem histórico familiar de glaucoma.


PURPOSE: To investigate whether there is a difference in topographic characteristics of optic nerve head analyzed by Heidelberg retina tomography (HRTII) in relatives of normal patients with or without history of open angle glaucoma. METHODS: Retrospective study analyzing the optic disc morphometry of normal patients with or without family history of glaucoma. Each participant underwent a routine examination, visual field testing, pachimetry and optic nerve head topography. Patients were classified according their family history of glaucoma in groups as first-degree (group 1), far second-degree (group 2) and no siblings with glaucoma (control group). Optic disc analyzed parameters were: disc area, rim area, cup area, cup/disc ratio (E/D) and linear cup/disc ratio. Statistical analysis was made through the SPSS 12.0 program considering only one randomized eye. A P value of less than 0.05 was considered statistically significant. RESULTS: Seventy-four patients (74 eyes) were included. The average age was 42.58 years. In the stereometric analysis, the comparison between the disc area from the group 1 and group 2 was statistically significant (P < 0.005), with marked overlap in group 1, fact that was repeated for the variables disc area, cup area, cup/disc ratio linear cup/disc ratio comparing first -degree and control group. There was no statistical difference comparing group 2 and 3 in the stereometric analysis. CONCLUSION: First-degree siblings of glaucoma patients present stereometric differences in optic disc when compared with patients without history of glaucoma. These differences were found in patients with no signs of the disease.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Ophthalmoscopy/methods , Optic Disk/anatomy & histology , Optic Disk/diagnostic imaging , Tomography/instrumentation , Tomography/methods , Glaucoma, Open-Angle/diagnostic imaging , Optic Disk/pathology , Medical Records , Retrospective Studies , Genetic Predisposition to Disease , Intraocular Pressure/physiology
15.
Rev. bras. eng. biomed ; 27(4): 259-272, dez. 2011. ilus
Article in Portuguese | LILACS | ID: lil-614001

ABSTRACT

Este trabalho propõe um novo método de contornos ativos (MCA), chamado de MCA Crisp, e o avalia na segmentação dos pulmões em imagens de Tomografia Computadorizada (TC). O MCA consiste em traçar uma curva inicial em torno ou dentro de um objeto de interesse. Esta curva se deforma, conforme algumas energias que atuam sobre a mesma, deslocando-a até as bordas do objeto. Este processo é realizado por iterações sucessivas de minimização de uma dada energia, associada à curva. Aplicando MCAs descritos na literatura na segmentação dos pulmões em imagens de TC, constatam-se limitações. Neste contexto, propõe‑-se o MCA Crisp para suprir tais limitações, propondo uma inicialização automática e uma nova energia externa baseada em regras e nas densidades radiológicas pulmonares. Realiza-se uma comparação entre os MCAs Tradicional, Balão, GVF e o método proposto para demonstrar a superioridade do novo método. Em seguida, para validar o MCA Crisp realiza-se uma análise qualitativa junto a um médico especialista na área de Pneumologia do Hospital Universitário Walter Cantídio da Universidade Federal do Ceará. Nesta análise, são utilizados 100  pulmões em imagens de TC. A eficiência da segmentação foi avaliada em  5 categorias, obtendo os seguintes resultados:   73% ótimas, sem falhas, 20% aceitáveis, com pequenos erros, 7% razoáveis, com erros grosseiros e  0% ruim, segmentando apenas uma pequena parte do pulmão, e  0% péssima, obtendo uma segmentação totalmente errada. Conclui-se que o MCA Crisp é um método útil para segmentar os pulmões em imagens de TC e com potencial para integrar sistemas que auxiliem o diagnóstico médico.


This paper proposes a new Active Contour Model (ACM), called ACM Crisp, and evaluates the segmentation of lungs in computed tomography (CT) images. An ACM draws a curve around or within the object of interest. This curve changes its shape, when some energy acts on it and moves towards the edges of the object. This process is performed by successive iterations of minimization of a given energy, associated with the curve. The ACMs described in the literature have limitations when used for segmentations of CT lung images. The ACM Crisp model overcomes these limitations, since it proposes automatic initiation and new external energy based on rules and radiological pulmonary densities. The paper compares other ACMs with the proposed method, which is shown to be superior. In order to validate the algorithm a medical expert in the field of Pulmonology of the Walter Cantídio University Hospital from the Federal University of Ceará carried out a qualitative analysis. In these analyses  100 CT lung images were used. The segmentation efficiency was evaluated into  5 categories with the following results for the ACM Crisp: 73% excellent, without errors, 20% acceptable, with small errors, and  7% reasonable, with large errors, 0% poor, covering only a small part of the lung, and  0% very bad, making a totally incorrect segmentation. In conclusion the ACM Crisp is considered a useful algorithm to segment CT lung images, and with potential to integrate medical diagnosis systems.


Subject(s)
Humans , Anatomy, Cross-Sectional/instrumentation , Diagnostic Imaging/trends , Tomography/instrumentation , Tomography/trends , Tomography , Image Interpretation, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted
16.
Arq. bras. med. vet. zootec ; 63(1): 36-39, Feb. 2011. ilus
Article in English | VETINDEX | ID: vti-6097

ABSTRACT

It is reported a case of an eight-year-old Yorkshire Terrier dog, with a history of prolonged use of prednisone in a dosage of 1mg/kg of body weight each 24 hours during two years. The helical computed tomography revealed hepatomegaly associated to a hyperattenuation of the parenchyma, with a radiodensity value of 82.55 Hounsfield units (HU). The spleen presented a mean radiodensity of 57.17HU, and a radiodensity difference of 25.38HU was observed between the two organs. Based on the history and findings of imaging technique, it was determined the presumptive diagnosis of steroidal hepatopathy compatible with accumulation of hepatic glycogen. It was concluded that computed tomography enabled the characterization of hepatic injury and the presumed diagnosis of steroidal hepatopathy.(AU)


Relata-se o caso de um cão da raça Yorkshire, de oito anos de idade, com histórico de tratamento com prednisona na dose de 1mg/kg de peso, a cada 24 horas, por dois anos. A tomografia computadorizada helicoidal revelou hepatomegalia associada à hiperatenuação, com radiodensidade de 82,55 unidades Hounsfield (HU). O baço apresentava radiodensidade média de 57,17HU, sendo observada diferença de radiodensidade de 25,38HU entre os dois órgãos. Por meio do histórico e dos achados da técnica de imagem, foi possível determinar o diagnóstico presuntivo de hepatopatia esteroidal compatível com acúmulo de glicogênio hepático. Concluiu-se que a tomografia computadorizada possibilitou caracterizar a lesão hepática e presumir o diagnóstico de hepatopatia esteroidal.(AU)


Subject(s)
Animals , Tomography/instrumentation , Dogs/classification , Liver Diseases/pathology , Glycogen Storage Disease
17.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);63(1): 36-39, Feb. 2011. ilus
Article in English | LILACS | ID: lil-582321

ABSTRACT

It is reported a case of an eight-year-old Yorkshire Terrier dog, with a history of prolonged use of prednisone in a dosage of 1mg/kg of body weight each 24 hours during two years. The helical computed tomography revealed hepatomegaly associated to a hyperattenuation of the parenchyma, with a radiodensity value of 82.55 Hounsfield units (HU). The spleen presented a mean radiodensity of 57.17HU, and a radiodensity difference of 25.38HU was observed between the two organs. Based on the history and findings of imaging technique, it was determined the presumptive diagnosis of steroidal hepatopathy compatible with accumulation of hepatic glycogen. It was concluded that computed tomography enabled the characterization of hepatic injury and the presumed diagnosis of steroidal hepatopathy.


Relata-se o caso de um cão da raça Yorkshire, de oito anos de idade, com histórico de tratamento com prednisona na dose de 1mg/kg de peso, a cada 24 horas, por dois anos. A tomografia computadorizada helicoidal revelou hepatomegalia associada à hiperatenuação, com radiodensidade de 82,55 unidades Hounsfield (HU). O baço apresentava radiodensidade média de 57,17HU, sendo observada diferença de radiodensidade de 25,38HU entre os dois órgãos. Por meio do histórico e dos achados da técnica de imagem, foi possível determinar o diagnóstico presuntivo de hepatopatia esteroidal compatível com acúmulo de glicogênio hepático. Concluiu-se que a tomografia computadorizada possibilitou caracterizar a lesão hepática e presumir o diagnóstico de hepatopatia esteroidal.


Subject(s)
Animals , Dogs/classification , Tomography/instrumentation , Glycogen Storage Disease , Liver Diseases/pathology
18.
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-663257

ABSTRACT

Objetivo: mensurar a localização do forame infraorbital (FIO) em peças anatômicas maceradas, considerando-se o dimorfismo sexual. Método: utilizou-se uma abordagem indutiva, procedimento estatístico e técnica de observação direta em laboratório, mediante crânios do acervo do Ossário do Departamento de Morfologia da Universidade Federal da Paraíba. O projeto obteve aprovação do Comitê de Ética em Pesquisa. Definiu-se a posição do FIO em relação aos dentes pelo método visual, e para as mensurações realizadas com paquímetro digital utilizaram-se duas distâncias: medida sagital (MS): margem infra-orbital - margem superior do forame; e medida transversal (MT): abertura piriforme - margem mediais do FIO, efetuadas por pesquisador calibrado. Obteve-se uma amostra de 23 crânios, procedendo-se a análise estatística com o teste t. Resultados: dentre os crânios dentados (34,8%; n=8) identificou-se o FIO no longo eixo do segundo pré-molar superior em 62,5% (n=5) no lado direito (LD) e 87,5% (n=7), lado esquerdo (LE). As médias, em milímetros, para a MS no sexo masculino foram 6,21 (±1,43) e 5,9 (±1,22) no LD e LE, respectivamente e para o feminino, 4,69 (±1,09) e 5,55 (±1,35). Na MT, as médias masculinas foram 16,56 (±1,94) para o LD e 16,38 (±1,75) para o LE. As médias femininas foram 15,55 (±2,53) e 16,64 (±1,94). Não houve diferença estatisticamente significante entre as medidas MS e MT direitas e esquerdas (p>0,05). No entanto, verificou-se significância entre a MS direita masculina e a feminina (p menor que 0,05). Conclusão: não houve variação significante na topografia do FIO em um mesmo indivíduo e no mesmo sexo, havendo, portanto variação entre os sexos.


Objective: to measure the location of the infraorbital foramen (IOF) in macerated anatomical specimens, considering the sexual dimorphism. Methods: it was used an inductive approach, a statistical technique and direct observation at the laboratory by means of skulls of the Ossuary's collection of Morphology's Department, Federal University of Paraíba. The project was approved by the Ethics Committee in Research. It was defined the position of IOF in relation to the teeth by the visual method and to the measurements, we used two different distances: sagittal measure (SM): infraorbital margin - foramen's superior margin; transverse measurement (TM): pyriform opening - the IOF's medial margin, conducted by calibrated researcher with a digital caliper. It was obtained a sample of 23 skulls, proceeding to statistical analysis using t test. Results: among dentate skulls (34.8%; n = 8), it was identified the IOF on the long axis of the second premolar in 62.5% (n = 5) on the right side (RS) and 87.5% (n = 7), left side (LS). The averages, in millimeters, for the SM in males was 6.21 (± 1.43) and 5.9 (± 1.22) in RS and LS, respectively and for females, 4.69 (± 1 09) and 5.55 (± 1.35). In TM, the male average was 16.56 (± 1.94) for RS and 16.38 (± 1.75) for the LS. The female average was 15.55 (± 2.53) and 16.64 (± 1.94). There wasn't statistically significant difference between the measurements SM and TM right and left (p greater than 0.05). However, there was significance between male and female MS right (p less than 0.05). Conclusion: there wasn't significant variation in the topography of IOF in the same individual and in the same sex, so, there is variation between the sexes.


Subject(s)
Humans , Male , Female , Skull/anatomy & histology , Sex Characteristics , Anatomy , Tooth , Brazil , Tomography/instrumentation , Cross-Sectional Studies/methods
19.
J Struct Biol ; 162(3): 368-79, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18358741

ABSTRACT

In electron tomography the reconstructed density function is typically corrupted by noise and artifacts. Under those conditions, separating the meaningful regions of the reconstructed density function is not trivial. Despite development efforts that specifically target electron tomography manual segmentation continues to be the preferred method. Based on previous good experiences using a segmentation based on fuzzy logic principles (fuzzy segmentation) where the reconstructed density functions also have low signal-to-noise ratio, we applied it to electron tomographic reconstructions. We demonstrate the usefulness of the fuzzy segmentation algorithm evaluating it within the limits of segmenting electron tomograms of selectively stained, plastic embedded spiny dendrites. The results produced by the fuzzy segmentation algorithm within the framework presented are encouraging.


Subject(s)
Tomography/methods , Algorithms , Artificial Intelligence , Electrons , Fuzzy Logic , Humans , Image Processing, Computer-Assisted , Models, Statistical , Observer Variation , Pattern Recognition, Automated , Reproducibility of Results , Software , Tomography/instrumentation , User-Computer Interface
20.
IEEE Trans Biomed Eng ; 55(2 Pt 1): 531-40, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18269988

ABSTRACT

Electrical impedance tomography is a technique to estimate the impedance distribution within a domain, based on measurements on its boundary. In other words, given the mathematical model of the domain, its geometry and boundary conditions, a nonlinear inverse problem of estimating the electric impedance distribution can be solved. Several impedance estimation algorithms have been proposed to solve this problem. In this paper, we present a three-dimensional algorithm, based on the topology optimization method, as an alternative. A sequence of linear programming problems, allowing for constraints, is solved utilizing this method. In each iteration, the finite element method provides the electric potential field within the model of the domain. An electrode model is also proposed (thus, increasing the accuracy of the finite element results). The algorithm is tested using numerically simulated data and also experimental data, and absolute resistivity values are obtained. These results, corresponding to phantoms with two different conductive materials, exhibit relatively well-defined boundaries between them, and show that this is a practical and potentially useful technique to be applied to monitor lung aeration, including the possibility of imaging a pneumothorax.


Subject(s)
Algorithms , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Plethysmography, Impedance/methods , Tomography/methods , Electric Impedance , Phantoms, Imaging , Plethysmography, Impedance/instrumentation , Reproducibility of Results , Sensitivity and Specificity , Tomography/instrumentation
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