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1.
Med Phys ; 51(4): 2806-2816, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37819009

RESUMO

BACKGROUND: Chest x-ray is widely utilized for the evaluation of pulmonary conditions due to its technical simplicity, cost-effectiveness, and portability. However, as a two-dimensional (2-D) imaging modality, chest x-ray images depict limited anatomical details and are challenging to interpret. PURPOSE: To validate the feasibility of reconstructing three-dimensional (3-D) lungs from a single 2-D chest x-ray image via Vision Transformer (ViT). METHODS: We created a cohort of 2525 paired chest x-ray images (scout images) and computed tomography (CT) acquired on different subjects and we randomly partitioned them as follows: (1) 1800 - training set, (2) 200 - validation set, and (3) 525 - testing set. The 3-D lung volumes segmented from the chest CT scans were used as the ground truth for supervised learning. We developed a novel model termed XRayWizard that employed ViT blocks to encode the 2-D chest x-ray image. The aim is to capture global information and establish long-range relationships, thereby improving the performance of 3-D reconstruction. Additionally, a pooling layer at the end of each transformer block was introduced to extract feature information. To produce smoother and more realistic 3-D models, a set of patch discriminators was incorporated. We also devised a novel method to incorporate subject demographics as an auxiliary input to further improve the accuracy of 3-D lung reconstruction. Dice coefficient and mean volume error were used as performance metrics as the agreement between the computerized results and the ground truth. RESULTS: In the absence of subject demographics, the mean Dice coefficient for the generated 3-D lung volumes achieved a value of 0.738 ± 0.091. When subject demographics were included as an auxiliary input, the mean Dice coefficient significantly improved to 0.769 ± 0.089 (p < 0.001), and the volume prediction error was reduced from 23.5 ± 2.7%. to 15.7 ± 2.9%. CONCLUSION: Our experiment demonstrated the feasibility of reconstructing 3-D lung volumes from 2-D chest x-ray images, and the inclusion of subject demographics as additional inputs can significantly improve the accuracy of 3-D lung volume reconstruction.


Assuntos
Pulmão , Tórax , Humanos , Raios X , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos
3.
Ultrasound Q ; 39(1): 53-60, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35943395

RESUMO

BACKGROUND: Thyroid ultrasonography is the first and perhaps most fundamental step for the radiological distinction of benign and malignant nodules. In this study, 2 radiologists reviewed the sonoelastographic and Doppler images of thyroid nodules and evaluated for the intraobserver and interobserver reliability. PURPOSE: We aimed to determine confusing nodule identifiers and sonographic features differently defined by observers. METHODS: A total of 157 nodules in 91 patients (male/female, 72:19) with ages ranging from 18 to 72 years old were included in the study. Ultrasonographic images and video clips of the nodules were obtained and presented to 2 reviewers unaware of the cytopathology results. Two observers defined the characteristics of the nodules based on previously determined criteria. Then, intraobserver and interobserver correlation coefficients were calculated for each subcategory. RESULTS: In the grayscale ultrasonographic examination, varying degrees from low to high interobserver correlation coefficients were obtained for different subcategories (between κ = 0.359 and κ = 0.821). In color Doppler examination, we obtained medium correlation coefficients ( κ = 0.493 and κ = 0.553). On the other hand, there was a high correlation coefficient in tissue compression elastography ( κ = 0.617 and κ = 0.638).According to our study results, elastographic pattern, shape of the nodule, presence of echogenic foci, and pathological lymph nodes are better predictors to determine the malignant potential of thyroid nodule with higher interobserver correlation. Therefore, these criteria may be used primarily for the evaluation of thyroid nodules. The intraobserver correlation coefficient was higher in the practitioner with longer experience, suggesting the importance of professional practice period on the decision-making process.


Assuntos
Técnicas de Imagem por Elasticidade , Nódulo da Glândula Tireoide , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Reprodutibilidade dos Testes , Ultrassonografia/métodos , Técnicas de Imagem por Elasticidade/métodos , Variações Dependentes do Observador
4.
J Am Podiatr Med Assoc ; 111(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478527

RESUMO

The few reports available on the vacuum phenomenon in the ankle joint refer to osteoarthritic and traumatic lesions. We present the first case concomitant with an osteochondral lesion of the talus. This case report presents computed tomographic images of the ankle. We speculate that the osteochondral lesion of the talus was the most likely cause of the vacuum phenomenon.


Assuntos
Tálus , Articulação do Tornozelo/diagnóstico por imagem , Humanos , Tálus/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Vácuo
5.
Eur J Gastroenterol Hepatol ; 33(9): 1222-1228, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34397640

RESUMO

BACKGROUND: While the relation of mean platelet volume (MPV) with inflammatory diseases is obvious, its role in nonalcoholic fatty liver disease (NAFLD) without cardiovascular comorbidities, obesity and diabetes mellitus is not clear. METHODS: A total of 249 patients (nonobese, nondiabetic and not having cardiac diseases) who underwent an abdominal ultrasonography assessment were enrolled. They were divided according to the absence (group 1) or presence (group 2) of hepatic steatosis. The patients with steatosis were further divided according to the severity of steatosis as group 2a (grade 1), 2b (grade 2) and 2c (grade 3). The demographic and laboratory features were compared between groups. RESULTS: Hepatic steatosis was absent in 120 patients and detected in 129 patients (grade 1, 2, 3 hepatic steatosis in 75, 49 and 5 patients, respectively). BMI, aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio and serum AST, ALT, triglyceride levels were significantly higher in group 2 than in group 1 (P < 0.001, P < 0.001, P < 0.001, P = 0.005, P < 0.001, respectively). BMI, serum AST and triglyceride levels were significant factors for NAFLD (P < 0.001, P = 0.018, P = 0.001). MPV was neither different between groups (P > 0.05) nor a predictor factor for NAFLD (P > 0.05). CONCLUSION: MPV is a useless parameter to detect NAFLD without cardiovascular comorbidities, obesity and diabetes mellitus.


Assuntos
Diabetes Mellitus , Hepatopatia Gordurosa não Alcoólica , Alanina Transaminase , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Humanos , Volume Plaquetário Médio , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/diagnóstico , Obesidade/epidemiologia
6.
Ann Saudi Med ; 38(3): 230-232, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29848942

RESUMO

Sclerosing encapsulated peritonitis (SEP) is a rare disease characterized by intestinal encasement within a fibrocollagenous membrane. Diagnosis of SEP may be challenging due to a lack of specific symptoms. Demonstration of clustered intestinal segments surrounded by a membranous sac by various imaging modalities is crucial to reveal the presence of SEP. Radiologic examinations play an important role in the management of the disease. This case is not unusual. Our intention is to emphasize the role of the imaging findings of a patient with primary SEP that presented with recurrent intestinal obstruction. SIMILAR CASES PUBLISHED: 118.


Assuntos
Obstrução Intestinal/etiologia , Fibrose Peritoneal/diagnóstico por imagem , Peritonite/diagnóstico por imagem , Adulto , Humanos , Obstrução Intestinal/diagnóstico por imagem , Masculino , Fibrose Peritoneal/complicações , Peritonite/complicações , Recidiva
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