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Radiology in 2030: A Guide for Strategic Planning
Sh. Akhlaghpoor
Iranian Journal of Radiology , 2008,
Abstract: Imaging science and technology are major contributors to the discovery of new knowledge in diagnosis and treatment of disease. Given such rapid past advances, is it not likely the future rate of progress will be at least as great? As part of the strategic plan is to estimate future change, it is necessary to have a vision for what will happen in radiology in next 20 years. There are several questions that we should find answer for them: 1. Which type of information clinicians will request from radiologists? 2. How will imaging devices of the future differ from those of the present? 3. What appearance might medical images of the future have? Only 30 years ago, radiologists depended heavily on plain radiographs, tomography, and catheter angiography.Presently, very high-resolution crosssectional imaging studies, four-dimensional sonography, and functional imaging techniques (such as brain activation studies and perfusion imaging) are common place. Physicians in the future will increasingly seek clinical information that is physiological, and not solely anatomical, in nature.Functional and molecular imaging will be the area of great development in future. Broadly, multidisciplinary, molecular imaging incorporates methods and concepts from molecular and cell biology, imaging sciences, chemistry, highthroughput"nbiology (eg, genomics, proteomics), nanotechnology, pharmacology, and bioinformatics. It is through molecular imaging that radiology is expected"nto play a critical role in advancing molecular medicine and potentially revolutionize patient care and biomedical research. Other promising options will be minimally invasive image-guided therapy and interventional radiology The convergence of molecular imaging and interventional radiology benefits both fields. This lecture is an effort to explain a roadmap for future in the field of Radiology.
Chorionic Villus Sampling and Marked Membrane Separation
Sh. Akhlaghpoor,A. Aziz Ahari
Iranian Journal of Radiology , 2010,
Abstract: Background/Objective: The major concern about the invasive prenatal diagnostic tests is the"nfrequency of procedure induced pregnancy loss. Chorionic Villus Sampling (CVS) is the invasive"ntest of choice in the first trimester after the 10th gestational week. Our experience suggests"nmarked chorioamniotic separation is an uncommon finding after the 10th gestational week. This"nstudy assesses the rate of marked membrane separation in a 10 to 14-week gestational period"nand its effect on post CVS fetal loss."nPatients and Methods: Forty-one patients (5.2%) were selected among 782 patients as cases"nwith marked membrane separation (mean maternal age, 26.9 years). CVS procedures were"nperformed with a 20-gauge Chiba needle attached to a 20-ml syringe under ultrasound guidance."nFollow-up was performed by phone call and clinical visits until 24 weeks of gestation. For the"ncontrol group, the follow-up was performed for only 2 weeks. Early fetal loss in the first two"nweeks of post procedural period, and late fetal loss from 2 weeks after procedure till the 24th"ngestational week were considered as CVS complications."nResults: We detected 2.4% early fetal losses after the procedure. Fourteen cases voluntarily"nunderwent therapeutic abortion due to beta-thalassemia or hemophilia. One fetus with"nmicrocephaly was spontaneously aborted in the 21st gestational week. Twenty-five neonates"nwere delivered alive at term and one prematurely at the 32nd week. Marked membrane separation"nhad no significant effect on early post CVS fetal loss rate."nConclusion: The procedure does not have a major impact on the early post CVS fetal loss in"npatients with marked membrane separation.
Correlation Between CT/MRI and Bremsstrahlung SPECT of 32P After Radioembolization of Hepatic Tumors
M. Amoui,E. Pirayesh,Sh. Akhlaghpoor,M. Khorrami
Iranian Journal of Radiology , 2010,
Abstract: Background/Objective: Radioembolization (RE) is a minimally invasive transcatheter therapy through which radioactive microspheres are infused into the hepatic arteries and selectively implanted within the tumor arterioles. Some therapeutic agents are particles incorporating pure β emitter elements (90Y, 32P) and do not have gamma radiation. Bremsstrahlung imaging of these radiotherapeutic agents confirms distribution of the radiotracer in hepatic tumors or probable extrahepatic deposition of radiopharmaceuticals and helps the physician to predict the patient's response to RE therapy. The aim of this study was demonstration of 32P images and its correlation with CT/MRI findings."nPatients and Methods: Ten patients with variable types of hepatic tumors treated with intra-arterial injection of 32P were included in this study. 24-72 hours after radiotracer administration, bremsstahlung SPECT imaging was performed in all patients with a single head gamma camera equipped with a medium energy collimator. Energy window setting of 100 keV±25% was selected. Reconstructed images were evaluated by two nuclear medicine specialists and one radiologist, and based on compatibility of 32P images with CT/MRI, a grading scale from 1 to 4 was used to express their correlations."nResults: By selecting optimized parameters for bremsstrahlung SPECT images of 32P, we could obtain good quality images. In nine patients, 32P distribution in the liver was correlated with anatomical findings of CT/MRI. "nConclusion: RE is appropriate to deliver high radiation doses to liver tumors with minimal accumulation in the normal liver tissue. Bremsstrahlung imaging is a useful method to confirm proper distribution of the radiotherapeutic agent, which has good correlation with anatomical findings.
Computer- Aided diagnosis system for the evaluation of chronic obstructive pulmonary disease on CT Images
Parsa Hosseini M,Soltanian-Zadeh H,Akhlaghpoor Sh
Tehran University Medical Journal , 2011,
Abstract: "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Chronic Obstructive Pulmonary Disease (COPD) is one of the most prevalent pulmonary diseases. Use of an automatic system for the detection and diagnosis of the disease will be beneficial to the patients' treatment decision-making process. In this paper, we propose a new approach for the Computer Aided Diagnosis (CAD) of the disease and determination of its severity axial CT scan images."n"nMethods: In this study, 24 lung CT scans in full inspiratory and expiratory states were performed. Variations in the normalized pattern of the lungs' external parenchyma were exploited as a feature for COPD diagnosis. Subsequently, a Bayesian classifier was used to classify variations into two normal and abnormal patterns for the discrimination of patients and healthy individuals. Finally, the accuracy of the classification was assessed statistically. "n"nResults: With the proposed method, the lungs parenchymal elasticity and air-trapping were determined quantitatively. The more this feature tended to zero, the more severe air-trapping and obstructive pulmonary disease is. By analyzing CT images in the healthy and patient groups, we calculated the hard threshold for the diagnosis of the disease. Clinical results tested by the mentioned method, suggested the effectiveness of this approach."n"nConclusion: In regard to the challenges of COPD diagnosis, we propose a new computer-aided design which may be helpful to physicians for a more accurate diagnosis of the disease. Moreover, this severity scoring algorithm may be useful for targeted disease management and risk-adjustment.
Evaluation of the Homing of Human CD34+ Cells in Mouse Bone Marrow Using Clinical MR Imaging
H. Mozdarani,Sh. Akhlaghpoor,A.A. Pourfatollah,M. Soleimani
Pakistan Journal of Biological Sciences , 2007,
Abstract: >There have been several reports using various superparamagnetic iron oxide (SPIO) nanoparticles to label mammalian cells for monitoring their temporal and spatial migration in vivo by Magnetic Resonance Imaging (MRI). The purpose of this study was to evaluate the efficiency of labeling cells using two commercially available FDA-approved agents: ferumoxide, a suspension of dextran-coated SPIO used as an MRI contrast agent and protamine sulfate used ex vivo as a cationic transfection agent to evaluate the use of clinical 1.5 Tesla magnetic resonance imaging equipment in showing the in vivo homing of iron oxide-labeled human CD34+ cells in irradiated mouse. After labeling human Hematopoietic (CD34+) stem cells with ferumoxide-protamine sulfate complex (FE-Pro), cellular toxicity, functional capacity and quantitative cellular iron incorporation were determined. FE-Pro labeled cells demonstrated neither short or long-term toxicity nor changes in colonogenic assay of the stem cells and their phenotype when compared with unlabeled cells. Efficient labeling with FE-Pro was observed with iron content per cell varying between 1.91±0.1 pg for CD34+ cells with 100% of cells labeled. After irradiation, Female Balb/c mice underwent MR imaging before and 12, 24, 48 and 72 h after intravenous injection of 0.5-1.5x107 labeled CD34+ cells. A significant decrease in MR signal intensity was observed in bone marrow at 24 and 48 h after injection. Our observations confirm that efficient labeling of cells with appropriate contrast agents should facilitate the translation of this method to clinical trials for evaluating the trafficking of infused or transplanted cells by MR Imaging.
Radiofrequency Ablation of Liver Tumors: The First Preliminary Report in Iran
Sh. Akhlaghpoor,Z. Tavakkoli,A.H. Jalali,M. Shakiba
Iranian Journal of Radiology , 2006,
Abstract: Background/Objective: Radiofrequency ablation (RFA) is emerging as a new therapeutic technique for unresectable hepatic malignancies. We report our experience with the use of this method for the first time in Iran. Patients and Methods: Eighteen patients with primary or metastatic hepatic malignancies, which were considered not suitable for surgical resection, were included in our study. RFA was performed via the percutaneous ultrasound–guided method, under general anesthesia, by an interventional radiologist. Patients were followed prospectively with contrast–enhanced CT or ultrasonography, and tumor marker serum levels 1, 3 and 6 months after RFA. Results: RFA was used to treat 26 tumors (diameters of 12-70 mm). These tumors included hepatocellular carcinoma in three cases and metastatic carcinoma in 23 cases. Three patients had complications: two bilomas and one abscess in the right lobe. At follow-ups, tumor recurred at the site of RFA in four tumors, all of which were over 4 cm in diameter. Conclusion: RFA is a procedure with the potential to be safe and effective for treating unre-sectable liver tumors.
Designing A New CAD System for Pulmonary Nodule Detection in High Resolution Computed Tomography (HRCT) Images
M Parsa Hosseini,H Soltanian-Zadeh,SH Akhlaghpoor,A Jalali
Tehran University Medical Journal , 2012,
Abstract: Background: Lung diseases and lung cancer are among the most dangerous diseases with high mortality in both men and women. Lung nodules are abnormal pulmonary masses and are among major lung symptoms. A Computer Aided Diagnosis (CAD) system may play an important role in accurate and early detection of lung nodules. This article presents a new CAD system for lung nodule detection from chest computed tomography (CT) images.Methods: Twenty-five adult patients with lung nodules in their CT scan images presented to the National Research Institute of Tuberculosis and Lung Disease, Masih Daneshvari Hospital, Tehran, Iran in 2011-2012 were enrolled in the study. The patients were randomly assigned into two experimental (9 female, 6 male, mean age 43±5.63 yrs) and control (6 female, 4 male, mean age 39±4.91 yrs) groups. A fully-automatic method was developed for detecting lung nodules by employing medical image processing and analysis and statistical pattern recognition algorithms.esults: Using segmentation methods, the lung parenchyma was extracted from 2-D CT images. Then, candidate regions were labeled in pseudo-color images. In the next step, some features of lung nodules were extracted. Finally, an artificial feed forward neural network was used for classification of nodules.Conclusion: Considering the complexity and different shapes of lung nodules and large number of CT images to evaluate, finding lung nodules are difficult and time consuming for physicians and include human error. Experimental results showed the accuracy of the proposed method to be appropriate (P<0.05) for lung nodule detection.
What Radiologists Should Know About Elastography
Shahram Akhlaghpoor
Iranian Journal of Radiology , 2010,
Abstract: Real-time elastography is a new method for mea-surement of tissue elasticity integrated in a sonogra-phy machine and is technically different from transient elastography."nIn recent studies, researchers have evaluated real-time elastography for the characterization and detection of focal lesions in the breast, thyroid gland and prostate gland. The tissue elasticity distribution may be calculated by the strain and stress of the examined tissue."nIn the first step, the amount of displacement of the reflected ultrasound echoes before and under com-pression are measured (stress field). In hard tissue, the amount of displacement of the reflected ultrasound echoes before and under compression is low, whereas in elastic or soft tissue, the amount of displacement is high because soft tissue may be compressed more than hard tissue."nIn the second step, a strain field is reconstructed from the measured displacements (strain image)."nAreas of high elasticity (i.e., soft tissue) appear as places of high strain, areas with low elasticity (i.e., hard tissue) appear as places of low strain. "nUsing the 3D tissue model (finite-element method), the examined tissue is divided in finite elements of equal stiffness before compression. During compression, the displacement of each element is measured. The finite-element method can then determine the tissue elasticity from the calculation of each element. The calculation of tissue elasticity distribution is performed in real time and the examination results are represented as color-coded images with the conventional B-mode image in the background. Because each elastography image is obtained in a few milliseconds, breathing does not cause any motion artifacts."nNowadays elastography is available in many ultra-sound scanners and its application in breast cancer and liver fibrosis is well established. Understanding the concept of this new technique and its application is necessary. We started elastography since 9 months ago and the results will be presented to share our experience with the audience.
MR Guided RF Ablation and Thermometery
Sara Eskandari,Shahram Akhlaghpoor
Iranian Journal of Radiology , 2009,
Abstract: "nIntroduction: Liver metastasis is detected in more than one million people in each year. Only 10% of them are eligible for surgery. Radiofrequency ablation is the most popular local ablation technique for the management of the other 90% of the metastases. Complete ablation of the lesion with a safe margin is the goal of such a local ablative method. There is no routine available technique for monitoring the treatment process. MRI is the only method which can monitor tissue ablation in real time however interaction of radiofrequency energy by MRI acquisition makes it impossible for clinical use. "nMaterials and Methods: In our in-vitro study, the effect of bipolar needles were evaluated on the signal intensity of theliver parenchyma. This evaluation was repeated 15 times. A calibration curve was also calculated from the in-vitro measurement of tissue temperature with an interstitial NTC sensor with dedicated data collecting software written by our team. Finally the correlation between temperature and signal intensity was prepared and during the RF ablation, the temperature map could be created in an almost real time manner. "nResults: Our results show an exponential calibration curve for sensors and a linear reduction of the signal intensities during the RF procedure. "nConclusion: We introduce a method for calibration of the MRI signal intensity with tissue temperature between alternative RF pulses. This method brings MR monitoring as the practical method in clinical use. By this innovative technique it is possible for all the hospitals and clinics to use their routine MR scanner for monitoring this ablative technique without any additional hardware.
The Conductivity of Indium Phosphide Irradiated by Fast Electrons  [PDF]
Sh. Sh. Rashidova
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.411183
Abstract:

In this work, studied electrical conductivity(s) and annealing of radiation defects in crystals of n-InP are irradiated by electrons energy of 6 MeV and doses of 1017 el/cm2 (centimeter) and 2 × 1017 el/cm2 (centimeter). It is shown that alongside point defects (in the form of complexes with impurity atoms in crystals of n-InP) also form the complex defects of the type of disordered areas, annealing of which proceeds at T > 300°C that binds accumulating radiation defects.

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