Classification of Pulmonary Nodules by Using Hybrid Features

Early detection of pulmonary nodules is extremely important for the diagnosis and treatment of lung cancer. In this study, a new classification approach for pulmonary nodules from CT imagery is presented by using hybrid features. Four different methods are introduced for the proposed system. The overall detection performance is evaluated using various classifiers. The results are compared to similar techniques in the literature by using standard measures. The proposed approach with the hybrid features results in 90.7% classification accuracy (89.6% sensitivity and 87.5% specificity)

Ciprofloxacin is not a better choice in the patients with diabetes suffering urinary tract infection

Objective: The aim of this study is to determine antibacterial susceptibilities of Gram-negative bacteria isolated from diabetic and non-diabetic patients as infectious agents of community-acquired urinary tract infections (UTI) and to compare their rates of resistance to the antibiotics frequently used in empirical treatment. Methods: Ninety-six diabetic and sixty-eight non-diabetic (total n=164) patients’ data were evaluated retrospectively who diagnosed as community-acquired urinary system infection and consulted to outpatient clinics of Department of Endocrinology and Infectious Diseases of Firat University School of Medicine between January 1st , 2014 and December 31st, 2014 whose urine cultures demonstrated Gram-negative bacteria were included in the study. Antibiotic susceptibilities of the isolated bacteria were determined using Vitek 2 automated system and the results were evaluated as sensitive and resistant. Results: In both diabetic and non-diabetic patient groups, most frequently Escherichia coli (88.5% in diabetic and 85.3% in non-diabetic groups) were isolated. In the diabetic group, microorganisms mostly demonstrated the highest rates of resistance against ampicillin, cephalosporins, ciprofloxacin, amoxicillin-clavulanic acid and in the non-diabetic group ampicillin, amoxicillin-clavulanic acid, cefuroxime and trimethoprim-sulfamethoxazole. Conclusion: Resistance to ciprofloxacin was at a significantly higher rate in the diabetic group. In diabetic patients, it will be more appropriate to give antibiotherapy in urinary system infections based on the antibacterial susceptibility test results

Monte Carlo simulation approaches to dose distributions for 6 MV photon beams in clinical linear accelerator

Monte Carlo method is often used in radiation therapy as utilized in all the branches of science. For this purpose, various preset codes are used for the dose calculations in radiotherapy. In this study, a new Monte Carlo Simulation Program (MCSP) was developed for the dose distributions of a clinical linear accelerator (LINAC) in water phantom. MCSP was carried out by taking into account the interactions of photons with matter in MATLAB (The Mathworks, Inc.). In the study, 6 MeV (6 MV photon mode) energies of photons are examined. In order to validate the performance and accuracy of the simulation, the experimental measurements and MCSP calculations were compared for both percentage depth dose curves and beam profiles. The Monte Carlo results show good agreement with experimental results. (C) 2014 Nalecz Institute of Biocybernetics and Biomedical Engineering. Published by Elsevier Urban & Partner Sp. z O.O. All rights reserved

Monte Carlo simulation of 10 MV photon beams and beam profile validations

In radiation therapy, various radiation energies have been used according to the size and depth of tumor for therapeutic purpose. The electron energies are used for superficial treatments, whereas photon energies such as 6 MV, 10 MV and 18 MV energy levels are utilized for the treatment of deeper tumors. The suitability of energy levels for treatment has been determined by dose distributions in water phantom. In this study, beam profiles of clinical linear accelerators for 10 MV photon beams in water phantom were obtained by using Monte Carlo Simulation Program (MCSP) developed. MCSP was carried out taking into account the interactions of photons with matter in MATLAB (The Mathworks, Inc.). Monte Carlo simulation results were calculated for 5x5, 10x10 and 20x20 cm2 field sizes at 5, 10 and 20 cm depths for the dose profiles. In order to validate the beam profiles, Monte Carlo results were compared with experimental results for 1 cm and 10 cm depths at all the field sizes. MCSP results have shown a good agreement with experimental results

Determination of dose distributions for clinical linear accelerators using Monte Carlo Method in water phantom

Radyasyon terapisinde Monte Carlo hesaplamaları için çeşitli kodlar kullanılmaktadır. Bu çalışmada, sudaki doz dağılımlarında Siemens PRIMUS klinik lineer hızlandırıcılardan (LINAC) fotonların fiziksel parametrelerinin etkileri için yeni bir Monte Carlo Simülasyon Programı (MCSP) geliştirilmiştir. MCSP, fotonların madde ile etkileşimleri dikkate alınarak yazılmıştır. Burada başlıca iki etkileşme dikkate alınmıştır: Compton (inkoherent) saçılması ve fotoelektrik olay. Bir nokta kaynaktan yayınlanarak su fantomu yüzeyine gelen fotonlar, bremsstrahlung ışınlarıdır. Foton takibinin yapılabilmesi için bu fotonların enerji dağılımlarının bilinmesi gerekir. Maksimum enerjisi 6 MeV (6 MV foton modu) olan bremsstrahlung fotonları dikkate alınmıştır. 6 MV foton modunda, yayınlanan fotonların enerjileri, Mohan tarafından deneysel olarak elde edilen spektrumdan örneklenmiştir (Mohan ve ark. 1985). MCSP'de doz profilleri ve yüzde derin doz eğrileri 107 parçacık takip edilerek hesaplanmıştır. Deneysel ölçümler, Siemens PRIMUS lineer hızlandırıcının 6 MV foton ışınları ve 48x48x48 cm3 boyutlu su fantomu kullanılarak yapılmıştır. 6 MV foton ışınları ile kaynak-fantom yüzeyi mesafesi, SSD=100 cm için yüzde derin dozlar, 3x3, 5x5, 10x10, 20x20 ve 30x30 cm2 alan boyutları için hem MCSP hem de yüksük iyonizasyon odası ile ölçülerek elde edilmiştir. 6 MV foton ışınları için doz profilleri, 3x3, 5x5, 10x10, 20x20 ve 30x30 cm2 alan boyutları ve beş farklı derinlik, 0, 3, 5, 10 ve 20 cm için hem MCSP hem de deneysel olarak elde edilmiştir. Simülasyonun doğruluğunu ve performansını incelemek için, ölçülen (deneysel) ve hesaplanan (MCSP) yüzde derin doz eğrileri ve doz profilleri karşılaştırılmıştır. Monte Carlo sonuçları, deneysel sonuçlarımız ile iyi bir uyum göstermektedir.Different codes were used for Monte Carlo calculations in radiation therapy. In this study, a new Monte Carlo Simulation Program (MCSP) was developed for the effects of the physical parameters of photons emitted from a Siemens PRİMUS clinical linear accelerator (LİNAC) on the dose distribution in water. For MCSP, it was written considering interactions of photons with matter. Here, it was taken into account mainly two interactions: The Compton (or incoherent) scattering and photoelectric effect. Photons which come to water phantom surface emitting from a point source were bremsstrahlung photons. It were ought to known the energy distributions of these photons for following photons. Bremsstrahlung photons which have 6 MeV (6 MV photon mode) maximum energies were taken into account. In the 6 MV photon mode, the energies of photons were sampled from using Mohan?s experimental energy spectrum (Mohan at al 1985). For MCSP, Dose (beam) profiles and Percentage Depth Dose (PDD) curves were calculated following simulating about 107 histories. The measurements were done using 6 MV photon beams of a Siemens PRİMUS linear accelerator and a 48x48x48 cm3 water phantom. Percentage depth doses for 6 MV photon beams were determined by both MCSP and measured with thimble ionization chamber for 3x3, 5x5, 10x10, 20x20 and 30x30 cm2 field sizes at SSD=100 cm. Dose profiles for 6 MV photons were determined at five different depths, 0, 3, 5, 10 and 20 cm for the reference field sizes of 3x3, 5x5, 10x10, 20x20 and 30x30 cm2 by both MCSP and measured. In order to investigate the performance and accuracy of the simulation, measured and calculated (MCSP) PDD curves and dose profiles were compared. The Monte Carlo results were shown good agreement with experimental measurements.Ali Osman Sönmez (AOS) Onkoloji Hastanes

Pulmoner nodüllerin malign-benign ayrımında topluluk öğrenme sınıflandırıcılarının başarımı

Bilgisayar destekli tespit sistemleri, pulmoner nodüllerin erken tanısında radyologlara yardımcı olmaktadır. Bu çalışmada, pulmoner nodüllerin malign benign ayrımı için özgün bir Bilgisayar Destekli Teşhis (BDT) sistemi önerilmiştir. Hekimlere hastalığın teşhisi sürecinde önemli katkı sağlayabilecek nitelikteki önerilen BDT sistemi, topluluk öğrenme sınıflandırıcıları kullanarak yüksek sınıflandırma başarım değerleri ortaya koymaktadır