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1.
Diagnostics (Basel) ; 13(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37443655

RESUMO

Temporal lobe epilepsy, a neurological disease that causes seizures as a result of excessive neural activities in the brain, is the most common type of focal seizure, accounting for 30-35% of all epilepsies. Detection of epilepsy and localization of epileptic focus are essential for treatment planning and epilepsy surgery. Currently, epileptic focus is decided by expert physician by examining the EEG records and determining EEG channel where epileptic patterns begins and continues intensely during seizure. Examination of long EEG recordings is very time-consuming process, requires attention and decision can vary depending on physician. In this study, to assist physicians in detecting epileptic focus side from EEG recordings, a novel deep learning-based computer-aided diagnosis system is presented. In the proposed framework, ictal epochs are detected using long short-term memory network fed with EEG subband features obtained by discrete wavelet transform, and then, epileptic focus identification is realized by using asymmetry score. This algorithm was tested on EEG database obtained from the Ankara University hospital. Experimental results showed ictal and interictal epochs were classified with accuracy of 86.84%, sensitivity of 86.96% and specificity of 89.68% on Ankara University hospital dataset, and 96.67% success rate was obtained on Bonn EEG dataset. In addition, epileptic focus was identified with accuracy of 96.10%, sensitivity of 100% and specificity of 93.80% by using the proposed deep learning-based algorithm and university hospital dataset. These results showed that proposed method can be used properly in clinical applications, epilepsy treatment and surgical planning as a medical decision support system.

2.
Diagnostics (Basel) ; 13(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36832228

RESUMO

The thyroid nodule risk stratification guidelines used in the literature are based on certain well-known sonographic features of nodules and are still subjective since the application of these characteristics strictly depends on the reading physician. These guidelines classify nodules according to the sub-features of limited sonographic signs. This study aims to overcome these limitations by examining the relationships of a wide range of ultrasound (US) signs in the differential diagnosis of nodules by using artificial intelligence methods. An innovative method based on training Adaptive-Network Based Fuzzy Inference Systems (ANFIS) by using Genetic Algorithm (GA) is used to differentiate malignant from benign thyroid nodules. The comparison of the results from the proposed method to the results from the commonly used derivative-based algorithms and Deep Neural Network (DNN) methods yielded that the proposed method is more successful in differentiating malignant from benign thyroid nodules. Furthermore, a novel computer aided diagnosis (CAD) based risk stratification system for the thyroid nodule's US classification that is not present in the literature is proposed.

3.
Rep Pract Oncol Radiother ; 24(4): 331-337, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31193931

RESUMO

AIM: In this study, we investigated initial electron parameters of Siemens Artiste Linac with 6 MV photon beam using the Monte Carlo method. BACKGROUND: It is essential to define all the characteristics of initial electrons hitting the target, i.e. mean energy and full width of half maximum (FWHM) of the spatial distribution intensity, which is needed to run Monte Carlo simulations. The Monte Carlo is the most accurate method for simulation of radiotherapy treatments. MATERIALS AND METHODS: Linac head geometry was modeled using the BEAMnrc code. The phase space files were used as input file to DOSXYZnrc simulation to determine the dose distribution in a water phantom. We obtained percent depth dose curves and the lateral dose profile. All the results were obtained at 100 cm of SSD and for a 10 × 10 cm2 field. RESULTS: We concluded that there existed a good conformity between Monte Carlo simulation and measurement data when we used electron mean energy of 6.3 MeV and 0.30 cm FWHM value as initial parameters. We observed that FWHM values had very little effect on PDD and we found that the electron mean energy and FWHM values affected the lateral dose profile. However, these effects are between tolerance values. CONCLUSIONS: The initial parameters especially depend on components of a linac head. The phase space file which was obtained from Monte Carlo Simulation for a linac can be used as calculation of scattering, MLC leakage, to compare dose distribution on patients and in various studies.

4.
São Paulo med. j ; 132(6): 348-352, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-726383

RESUMO

CONTEXT AND OBJECTIVE: Lasers are widely used in treating symptomatic benign prostatic hyperplasia. In current practice, potassium titanyl phosphate (KTP) lasers are the most common type of laser systems used. The aim here was to evaluate the rapid effect of high-power laser systems after application of hypericin. DESIGN AND SETTING: Experimental animal study conducted in the Department of Urology, Gülhane Military Medical Academy, Ankara, Turkey, in 2012. METHODS: Sixteen rats were randomized into four groups: 120 W KTP laser + hypericin; 120 W KTP laser alone; 80 W KTP laser + hypericin; and 80 W KTP laser alone. Hypericin was given intraperitoneally two hours prior to laser applications. The laser incisions were made through the quadriceps muscle of the rats. The depth and the width of the laser incisions were evaluated histologically and recorded. RESULTS: To standardize the effects of the laser, we used the ratio of depth to width. These new values showed us the depth of the laser application per unit width. The new values acquired were evaluated statistically. Mean depth/width values were 231.6, 173.6, 214.1 and 178.9 in groups 1, 2, 3 and 4, respectively. The most notable result was that higher degrees of tissue penetration were achieved in the groups with hypericin (P < 0.05). CONCLUSIONS: The encouraging results from our preliminary study demonstrated that hypericin may improve the effects of KTP laser applications. .


CONTEXTO E OBJETIVO: Lasers são amplamente utilizados no tratamento de hiperplasia benigna de próstata sintomática. Na prática atual, lasers de fosfato de titanilo de potássio (KTP) são os tipos mais comuns usados dos sistemas. O objetivo foi avaliar o efeito rápido do sistema laser de alta potência após a aplicação de hipericina. TIPO DE ESTUDO E LOCAL: Estudo experimental animal, realizado no Departamento de Urologia, Academia de Medicina Militar de Gülhane, Ancara, Turquia, em 2012. MÉTODOS: 16 ratos foram divididos aleatoriamente em 4 grupos: 120W KTP laser + hipericina; 120W KTP laser somente; 80W KTP laser + hipericina; 80W KTP laser somente. Hipericina foi dada intraperitonealmente duas horas antes da aplicação do laser. As incisões a laser foram feitas através do músculo quadríceps dos ratos. A profundidade e a largura das incisões a laser foram avaliadas histologicamente e registradas. RESULTADOS: Para padronizar o efeito do laser foi utilizada a razão entre profundidade e largura. Estes novos valores nos mostraram a profundidade da aplicação do laser de largura por unidade. Os novos valores adquiridos foram avaliados estatisticamente. Os valores da média de profundidade/largura foram 231,6, 173,6, 214,1 e 178,9 nos grupos 1, 2, 3 e 4, respectivamente. O resultado mais notável foi atingir altos graus de penetração tecidual nos grupos com hipericina (P < 0,05). CONCLUSÕES: Os resultados promissores do nosso estudo preliminar mostraram que hipericina pode melhorar os efeitos das aplicações do laser KTP. .


Assuntos
Animais , Masculino , Lasers de Estado Sólido , Músculo Esquelético/efeitos dos fármacos , Perileno/análogos & derivados , Radiossensibilizantes/farmacologia , Modelos Animais , Músculo Esquelético/patologia , Músculo Esquelético/efeitos da radiação , Perileno/farmacologia , Distribuição Aleatória , Ratos Wistar , Coxa da Perna/patologia , Coxa da Perna/efeitos da radiação , Fatores de Tempo
5.
Arch Med Res ; 37(7): 840-3, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16971222

RESUMO

BACKGROUND: There has been growing public concern on the effects of electromagnetic radiation (EMR) emitted by cellular phones on human health. Many studies have recently been published on this topic. However, possible consequences of the cellular phone usage on human sperm parameters have not been investigated adequately. METHODS: A total number of 27 males were enrolled in the study. The semen sample obtained from each participant was divided equally into two parts. One of the specimens was exposed to EMR emitted by an activated 900 MHz cellular phone, whereas the other was not. The concentration and motility of the specimens were compared to analyze the effects of EMR. Assessment of sperm movement in all specimens was performed using four criteria: (A) rapid progressive, (B) slow progressive, (C) nonprogressive, (D) no motility. RESULTS: Statistically significant changes were observed in the rapid progressive, slow progressive and no-motility categories of sperm movement. EMR exposure caused a subtle decrease in the rapid progressive and slow progressive sperm movement. It also caused an increase in the no-motility category of sperm movement. There was no statistically significant difference in the sperm concentration between two groups. CONCLUSIONS: These data suggest that EMR emitted by cellular phone influences human sperm motility. In addition to these acute adverse effects of EMR on sperm motility, long-term EMR exposure may lead to behavioral or structural changes of the male germ cell. These effects may be observed later in life, and they are to be investigated more seriously.


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Motilidade dos Espermatozoides/efeitos dos fármacos , Humanos , Masculino
6.
Surg Laparosc Endosc Percutan Tech ; 15(5): 271-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16215485

RESUMO

CO2 pneumoperitoneum used in endoscopic surgery induces systemic effects by CO2 absorption. It was claimed that a reduction in CO2 pneumoperitoneum-induced metabolic hypoxemia was achieved by the addition of small amounts of O2 to the CO2 in a rabbit ventilated model. We reevaluated the effects of the addition of O2 to the CO2 pneumoperitoneum upon CO2 absorption in a rabbit model. The effects of a pneumoperitoneum using 100% CO2, 90% CO2 + 10% O2, 95% CO2 + 5% O2, or 100% O2 on arterial blood gases, acid base and O2 homeostasis were evaluated in nonintubated rabbits. A pneumoperitoneum pressure of 10 cm H2O (approximately 7.35 mm Hg) was used. CO2 pneumoperitoneum of 120 minutes affected blood gases and acid base homeostasis. Whereas partial pressure of CO2 and HCO3 increased (P < 0.001) during pneumoperitoneum, pH and partial pressure of O2 decreased (P < 0.001). Similar results were obtained in O2-CO2 pneumoperitoneum (P > 0.05). CO2 pneumoperitoneum profoundly affected blood gases and acid base homeostasis, resulting in metabolic hypoxemia. The addition of O2 to the CO2 did not prevent the systemic effects of CO2 pneumoperitoneum in nonintubated animals.


Assuntos
Endoscopia/métodos , Oxigênio/administração & dosagem , Pneumoperitônio Artificial/efeitos adversos , Animais , Dióxido de Carbono/administração & dosagem , Feminino , Hipóxia/etiologia , Coelhos
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