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1.
Pol J Radiol ; 88: e529-e534, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125812

RESUMO

Purpose: The aim of the study was to analyse the usefulness of core biopsy in the diagnosis of malignant neoplasms of the pancreas - sensitivity and accuracy of diagnosis, safety of the procedure, indication of factors that may increase the risk of complications after biopsy. Material and methods: A retrospective analysis of data was performed in a group of 100 patients diagnosed with a focal lesion of the pancreas, qualified for a core biopsy. Results: The results are a sensitivity of 92%, a specificity of 100%, and an accuracy of 93.3%. The incidence of more severe complications according to the Clavien-Dindo classification was 1% (one case in the material studied). The results of the analysis were compared with the results of other authors, showing similar values for the sensitivity and specificity of the method and low rates of serious complications; it also seems that the tissue material obtained by core biopsy has higher diagnostic potential than that obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), currently considered the method of choice. In addition, the costs of transabdominal biopsy and endoscopic biopsy were compared; the lower cost of the former may be an important economic issue when choosing the biopsy method. Conclusions: The results show core biopsy to be a sensitive, accurate, and safe method for obtaining the tissue necessary to plan treatment in patients with pancreatic cancer.

2.
Psychiatr Danub ; 29(Suppl 3): 357-360, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953791

RESUMO

BACKGROUND: There is evidence for neurosyphilis being associated with the central nervous system vasculitis involving medium and small vessels. As the hemispheric white matter is the major target of these vascular alterations the white matter axonal and myelination disruption may be observed employing measure for the rate of water molecule diffusion. High apparent diffusion coefficient (ADC) correspond to unimpeded water diffusion and indicating white matter disintegration. CASE REPORTS: In a retrospective study exploringcentral nervous system magnetic resonance (MR) images of two subjects presenting with neurosyphilis the ADC values were found to be increased as related to normal values being accompanied with normal appearing white matter of hemispheres. CONCLUSIONS: Applying ADC analysis to evaluate the brain in patients with neurosyphilis may reveal undetectable changes and explain the scale of abnormalities that occur in CNS. The increased mean ADC valuesin the normal appearing white matter of the hemispheres may correlate with neuropsychoatric symptomatology in syphilis.


Assuntos
Neurossífilis , Substância Branca , Imagem de Difusão por Ressonância Magnética , Humanos , Neurossífilis/complicações , Neurossífilis/diagnóstico por imagem , Estudos Retrospectivos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
3.
Int J Med Inform ; 189: 105522, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38852288

RESUMO

BACKGROUND: The development of computer-aided diagnosis systems in breast cancer imaging is exponential. Since 2016, 81 papers have described the automated segmentation of breast lesions in ultrasound images using artificial intelligence. However, only two papers have dealt with complex BI-RADS classifications. PURPOSE: This study addresses the automatic classification of breast lesions into binary classes (benign vs. malignant) and multiple BI-RADS classes based on a single ultrasonographic image. Achieving this task should reduce the subjectivity of an individual operator's assessment. MATERIALS AND METHODS: Automatic image segmentation methods (PraNet, CaraNet and FCBFormer) adapted to the specific segmentation task were investigated using the U-Net model as a reference. A new classification method was developed using an ensemble of selected segmentation approaches. All experiments were performed on publicly available BUS B, OASBUD, BUSI and private datasets. RESULTS: FCBFormer achieved the best outcomes for the segmentation task with intersection over union metric values of 0.81, 0.80 and 0.73 and Dice values of 0.89, 0.87 and 0.82, respectively, for the BUS B, BUSI and OASBUD datasets. Through a series of experiments, we determined that adding an extra 30-pixel margin to the segmentation mask counteracts the potential errors introduced by the segmentation algorithm. An assembly of the full image classifier, bounding box classifier and masked image classifier was the most accurate for binary classification and had the best accuracy (ACC; 0.908), F1 (0.846) and area under the receiver operating characteristics curve (AUROC; 0.871) in the BUS B and ACC (0.982), F1 (0.984) and AUROC (0.998) in the UCC BUS datasets, outperforming each classifier used separately. It was also the most effective for BI-RADS classification, with ACC of 0.953, F1 of 0.920 and AUROC of 0.986 in UCC BUS. Hard voting was the most effective method for dichotomous classification. For the multi-class BI-RADS classification, the soft voting approach was employed. CONCLUSIONS: The proposed new classification approach with an ensemble of segmentation and classification approaches proved more accurate than most published results for binary and multi-class BI-RADS classifications.

4.
J Imaging ; 10(5)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38786569

RESUMO

Image quality assessment of magnetic resonance imaging (MRI) data is an important factor not only for conventional diagnosis and protocol optimization but also for fairness, trustworthiness, and robustness of artificial intelligence (AI) applications, especially on large heterogeneous datasets. Information on image quality in multi-centric studies is important to complement the contribution profile from each data node along with quantity information, especially when large variability is expected, and certain acceptance criteria apply. The main goal of this work was to present a tool enabling users to assess image quality based on both subjective criteria as well as objective image quality metrics used to support the decision on image quality based on evidence. The evaluation can be performed on both conventional and dynamic MRI acquisition protocols, while the latter is also checked longitudinally across dynamic series. The assessment provides an overall image quality score and information on the types of artifacts and degrading factors as well as a number of objective metrics for automated evaluation across series (BRISQUE score, Total Variation, PSNR, SSIM, FSIM, MS-SSIM). Moreover, the user can define specific regions of interest (ROIs) to calculate the regional signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), thus individualizing the quality output to specific use cases, such as tissue-specific contrast or regional noise quantification.

5.
Gastroenterol Res Pract ; 2019: 6590729, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485219

RESUMO

BACKGROUND: The aim of the study was to evaluate the prognostic properties of perfusion parameters of liver parenchyma based on computed tomography (CT) of patients with acute pancreatitis (AP) made on the first day of onset of symptoms, to assess their usefulness in identifying patients with increased risk of the development of severe AP. METHODS: 79 patients with clinical symptoms and biochemical criteria indicative of AP underwent perfusion computed tomography (p-CT) within 24 hours after onset of the symptoms. Perfusion parameters in 41 people who developed a severe form of AP were compared with parameters in 38 patients in whom the course of AP was mild. RESULTS: Statistical differences in the liver perfusion parameters between the group of patients with mild and severe AP were shown. The permeability-surface area product was significantly lower, and the hepatic arterial fraction was significantly higher in the group of patients with progression of AP. CONCLUSIONS: Based on the results, it seems that p-CT performed on the first day from the onset of AP is a method that, by revealing disturbances in hepatic perfusion, can help in identifying patients with increased risk of the development of severe AP.

6.
PLoS One ; 11(1): e0146965, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26784348

RESUMO

PURPOSE: Severe acute pancreatitis (AP) is still a significant clinical problem which is associated with a highly mortality. The aim of this study was the evaluation of prognostic value of CT regional perfusion measurement performed on the first day of onset of symptoms of AP, in assessing the risk of developing severe form of acute pancreatitis. MATERIAL AND METHODS: 79 patients with clinical symptoms and biochemical criteria indicative of acute pancreatitis (acute upper abdominal pain, elevated levels of serum amylase and lipase) underwent perfusion CT within 24 hours after onset of symptoms. The follow-up examinations were performed after 4-6 days to detect progression of the disease. Perfusion parameters were compared in 41 people who developed severe form of AP (pancreatic and/or peripancreatic tissue necrosis) with parameters in 38 consecutive patients in whom course of AP was mild. Blood flow, blood volume, mean transit time and permeability surface area product were calculated in the three anatomic pancreatic subdivisions (head, body and tail). At the same time the patient's clinical status was assessed by APACHE II score and laboratory parameters such as CRP, serum lipase and amylase, AST, ALT, GGT, ALP and bilirubin were compared. RESULTS: Statistical differences in the perfusion parameters between the group of patients with mild and severe AP were shown. Blood flow, blood volume and mean transit time were significantly lower and permeability surface area product was significantly higher in patients who develop severe acute pancreatitis and presence of pancreatic and/or peripancreatic necrosis due to pancreatic ischemia. There were no statistically significant differences between the two groups in terms of evaluated on admission severity of pancreatitis assessed using APACHE II score and laboratory tests. CONCLUSIONS: CT perfusion is a very useful indicator for prediction and selection patients in early stages of acute pancreatitis who are at risk of developing pancreatic and/or peripancreatic necrosis already on the first day of the onset of symptoms and can be used for treatment planning and monitoring of therapy of acute pancreatitis. Early suspicion of possible pancreatic necrosis both on the basis of scores based on clinical status and laboratory tests have low predictive value.


Assuntos
Pâncreas/irrigação sanguínea , Pancreatite Necrosante Aguda/patologia , Imagem de Perfusão/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Amilases/sangue , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Lipase/sangue , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/diagnóstico por imagem , Prognóstico
7.
J Orthop ; 10(2): 70-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24403753

RESUMO

AIMS: Pseudoarthrosis and delayed bone union are the main complications in the healing process of long bones fractures. The surgical intervention is currently the treatment of choice, but there is a number of non-operative interventions are being developed, such as extracorporeal shock wave therapy (ESWT). There is a range of issues related to the proper qualification, monitoring, and outcome assessment measures. Bone scintigraphy (BS) exclusively allows the assessment of the bone turnover dynamics in non-invasive, semi quantitative method. METHODS: The study group comprised of 31 subjects with bone healing complications. The study population was divided in two subgroups as related to the treatment outcome assessed 24 weeks after ESWT procedure. Group I (n = 19) included the cases with no complete bone union. Group II (n = 12) covered the subjects with complete bone union. BS was performed right before ESWT and 2 weeks after the procedure. RESULTS: Increase of agent uptake after ESWT procedure was noted in both groups which proves that ESWT increases bone metabolism dynamics in most patients. Significantly higher uptake increase was noted in patients with complete bone union. In patients with unsuccessful treatment the agent uptake before ESWT was much higher. Two weeks after ESWT procedure BS reveals an increase in bone metabolism in the area of complicated fracture proving positive reaction of bony tissue on mechanical waves. CONCLUSION: Scintigraphy may facilitate qualification patients with bone union disorders for further mode of treatment. One can suppose that positive bone reaction is achievable only in bone where the metabolism is lowered.

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