Biomedical Image Processing / Medical Image Processing
Leila Azimi; Nader Riahi Alam; Kavoos Firuozniya; Hamid Reza Saligheh Rad; Mojtaba Miri; Manizheh Pakravan; Anamollah Shahmohammadi
Volume 8, Issue 2 , June 2014, , Pages 113-123
Abstract
Gliomas are the most common primary neoplasm of the brain, varying histologically from low grade to high-grade. Perfusion-weighted MRI techniques have permitted the creation of cerebral blood volume (CBV) value, leading to the qualitative and quantitative assessment of tumor vascularity. This research ...
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Gliomas are the most common primary neoplasm of the brain, varying histologically from low grade to high-grade. Perfusion-weighted MRI techniques have permitted the creation of cerebral blood volume (CBV) value, leading to the qualitative and quantitative assessment of tumor vascularity. This research aimed at assessing the rCBV and the ADC values in core and peritumoral areas glioma brain tumors and determining of significance rCBV of values i Alpha I In evaluating brain tumor. Ten patients with non-enhancing supratentorial gliomas were evaluated by diffusion weighted imaging (DWI) and standard dynamic susceptibility contrast-enhanced gradient echo during first pass of a bolus injection of contrast material before surgical resection. Six low-grade gliomas (WHO Grade II) and 4 high-grade gliomas (III, IV) were evaluated. Alpha Both the apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) values were calculated by a standard program on the solid portion of the tumor in the peritumoural area as well as contra lateral white matter. In perfusion, mean rCBVmax in high-grade and low-grade tumors were obtained (3.47±0.92), (2.37±0.49)-(1.66±0.68), (1.15±0.39) for core and peritumoral regions, respectively. In diffusion method, mean ADC in high-grade and low grade tumors were (0.53±0.07), (0.91±0.18)-(1.24±0.27), (1.007±0.33) for core and peritumoral regions, respectively. It was concluded that the values rCBVs are important in determining the grade of tumor and we propose that perfusion weighted imaging be done for all patients before surgery.
Nano-Biomaterials
Sahar Rezaei; Nader Riahi Alam
Volume 8, Issue 2 , June 2014, , Pages 151-158
Abstract
Detection of tumors at an early stage is important for the diagnosis of cancer. Therefore, to detect cancer cells it is necessary to distinguish between metastases from normal cells at an early stage. Due to the large size and coverage necessary to prevent chemical reactions of the current contrast agents ...
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Detection of tumors at an early stage is important for the diagnosis of cancer. Therefore, to detect cancer cells it is necessary to distinguish between metastases from normal cells at an early stage. Due to the large size and coverage necessary to prevent chemical reactions of the current contrast agents in the body, they are just applicable to the extracellular space. Due to the small size of nanoparticles in comparison to cells, it is possible for them to enter the cells. Therefore, these materials are used for molecular imaging. In this paper, variations in the external magnetic field (Tesla) due to magnetic nanoparticles in homogeneous tissue were studied by the finite element method. For this purpose, a simulation was performed in the presence of magnetic nanoparticles and without it. By the finite element method, conversion of differential and integral governing equations to simple and solvable equations that are numerically stable was made possible. The results obtained indicate that the external magnetic field is intensified by the presence of magnetic nanoparticles.
Biomedical Image Processing / Medical Image Processing
Nader Riahi Alam; Reza Aghaeizade Zoroofi; Masoume Giti; Arian Deldari; Alireza Ahmadian
Volume 1, Issue 3 , June 2007, , Pages 157-165
Abstract
In this study, the need of a CAD system and its capabilities has been investigated and then a sample program for a mammographic CAD system proper to Iranian tropical patients was designed. In the first step, the analog mammographic images were digitized by 56 and 112 mm spatial resolution and then were ...
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In this study, the need of a CAD system and its capabilities has been investigated and then a sample program for a mammographic CAD system proper to Iranian tropical patients was designed. In the first step, the analog mammographic images were digitized by 56 and 112 mm spatial resolution and then were processed by the designed sample program. Analysis and technical details for designing and implementing the program included for following steps: The capability of the program image displayer consisting of viewing four mammographic images from four breast views (RCC, RMLO, LCC, LMLO) in one window, determining breast region by background removing and other conventional preprocessing application tools; Software processing tools including theresholding, histogram, ROI determination; Patient information fields such as clinical information, conventional reporting section as used in radiological department in Iran; Computer-aided diagnostic section including proper diagnostic processing algorithm to automatic detection of breast abnormality. For instance the application of wavelet and fuzzy logic for detecting malignant clusters of microcalcification. The introduced mammographic CAD system can provide the collection, organizing and the availability of the patient local information. Therefore by using the prepared database the evaluation of the sensitivity and specifity of the detecting algorithm for comparison of different research methods would be possible.