Publications by authors named "Maryam Mohammadzadeh"

18 Publications

  • Page 1 of 1

Machine Learning Approach to Differentiation of Peripheral Schwannomas and Neurofibromas: A Multi-Center Study.

Neuro Oncol 2021 Sep 6. Epub 2021 Sep 6.

Department of Neurosurgery, Stanford University, Stanford, CA, USA.

Background: Non-invasive differentiation between schwannomas and neurofibromas is important for appropriate management, preoperative counseling, and surgical planning, but has proven difficult using conventional imaging. The objective of this study was to develop and evaluate machine learning approaches for differentiating peripheral schwannomas from neurofibromas.

Methods: We assembled a cohort of schwannomas and neurofibromas from 3 independent institutions and extracted high-dimensional radiomic features from gadolinium-enhanced, T1-weighted MRI using the PyRadiomics package on Quantitative Imaging Feature Pipeline. Age, sex, neurogenetic syndrome, spontaneous pain, and motor deficit were recorded. We evaluated the performance of 6 radiomics-based classifier models with and without clinical features and compared model performance against human expert evaluators.

Results: 107 schwannomas and 59 neurofibroma were included. The primary models included both clinical and imaging data. The accuracy of the human evaluators (0.765) did not significantly exceed the no-information rate (NIR), whereas the Support Vector Machine (0.929), Logistic Regression (0.929), and Random Forest (0.905) classifiers exceeded the NIR. Using the method of DeLong, the AUC for the Logistic Regression (AUC=0.923) and K Nearest Neighbor (AUC=0.923) classifiers was significantly greater than the human evaluators (AUC=0.766; p = 0.041).

Conclusions: The radiomics-based classifiers developed here proved to be more accurate and had a higher AUC on the ROC curve than expert human evaluators. This demonstrates that radiomics using routine MRI sequences and clinical features can aid in differentiation of peripheral schwannomas and neurofibromas.
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http://dx.doi.org/10.1093/neuonc/noab211DOI Listing
September 2021

Machine Assist for Pediatric Posterior Fossa Tumor Diagnosis: A Multinational Study.

Neurosurgery 2021 Aug 14. Epub 2021 Aug 14.

Department of Neurosurgery, Great Ormond Street Hospital, London, United Kingdom.

Background: Clinicians and machine classifiers reliably diagnose pilocytic astrocytoma (PA) on magnetic resonance imaging (MRI) but less accurately distinguish medulloblastoma (MB) from ependymoma (EP). One strategy is to first rule out the most identifiable diagnosis.

Objective: To hypothesize a sequential machine-learning classifier could improve diagnostic performance by mimicking a clinician's strategy of excluding PA before distinguishing MB from EP.

Methods: We extracted 1800 total Image Biomarker Standardization Initiative (IBSI)-based features from T2- and gadolinium-enhanced T1-weighted images in a multinational cohort of 274 MB, 156 PA, and 97 EP. We designed a 2-step sequential classifier - first ruling out PA, and next distinguishing MB from EP. For each step, we selected the best performing model from 6-candidate classifier using a reduced feature set, and measured performance on a holdout test set with the microaveraged F1 score.

Results: Optimal diagnostic performance was achieved using 2 decision steps, each with its own distinct imaging features and classifier method. A 3-way logistic regression classifier first distinguished PA from non-PA, with T2 uniformity and T1 contrast as the most relevant IBSI features (F1 score 0.8809). A 2-way neural net classifier next distinguished MB from EP, with T2 sphericity and T1 flatness as most relevant (F1 score 0.9189). The combined, sequential classifier was with F1 score 0.9179.

Conclusion: An MRI-based sequential machine-learning classifiers offer high-performance prediction of pediatric posterior fossa tumors across a large, multinational cohort. Optimization of this model with demographic, clinical, imaging, and molecular predictors could provide significant advantages for family counseling and surgical planning.
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http://dx.doi.org/10.1093/neuros/nyab311DOI Listing
August 2021

Deep COVID DeteCT: an international experience on COVID-19 lung detection and prognosis using chest CT.

NPJ Digit Med 2021 Jan 29;4(1):11. Epub 2021 Jan 29.

Department of Radiology, School of Medicine, Stanford University, Stanford, CA, 94305, USA.

The Coronavirus disease 2019 (COVID-19) presents open questions in how we clinically diagnose and assess disease course. Recently, chest computed tomography (CT) has shown utility for COVID-19 diagnosis. In this study, we developed Deep COVID DeteCT (DCD), a deep learning convolutional neural network (CNN) that uses the entire chest CT volume to automatically predict COVID-19 (COVID+) from non-COVID-19 (COVID-) pneumonia and normal controls. We discuss training strategies and differences in performance across 13 international institutions and 8 countries. The inclusion of non-China sites in training significantly improved classification performance with area under the curve (AUCs) and accuracies above 0.8 on most test sites. Furthermore, using available follow-up scans, we investigate methods to track patient disease course and predict prognosis.
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http://dx.doi.org/10.1038/s41746-020-00369-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7846563PMC
January 2021

A Multicenter Survey on the Trend of Chest CT Scan Utilization: Tracing the First Footsteps of COVID-19 in Iran.

Arch Iran Med 2020 11 1;23(11):787-793. Epub 2020 Nov 1.

Department of Radiology, Shohada-E-Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Background: Chest computed tomography (CT) scan has been used widely to diagnose COVID-19 in Iran.

Objectives: To trace the footsteps of COVID-19 in Iran by exploring the trend in using chest CT scans and its economic impact on radiology departments. Methods: In this cross-sectional study, the number of imaging examinations from 33 tertiary radiology departments in 9 large cities of Iran was collected from September 23, 2019 to March 20, 2020 (Months 1 to 6) and the corresponding months in 2018-2019.

Results: A 50.2% increase was noted in the chest CT scan utilization in 2019-2020 compared to 2018-2019. This increase was +15%, +15%, +27%, +2%, +1% in Months 1-5 of 2019-2020, respectively. In Month 6 of 2019-2020, a 251% increase in the acquisition of chest CT scans was observed compared to the Month 6 of 2018-2019. Following negative balance of revenue from Month 1 to 5 with respect to the inflation rate, the total income in Month 6 was further 1.5% less than the same Month in 2018-19.

Conclusion: The observed peak in chest CT utilization in Month 3 prior to the surge in Month 6 could be explained by the seasonal influenza. However, unawareness about an emerging viral disease, i.e. COVID-19, might have underutilized chest CT in Months 4 and 5 before the official announcement in Month 6. The unbalanced increase in the workload of radiology departments in the shortage of cardiothoracic radiologists with the simultaneous decrease in income initiated a vicious cycle that worsened the economic repercussions of the pandemic.
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http://dx.doi.org/10.34172/aim.2020.105DOI Listing
November 2020

Guidance for Ophthalmologists and Ophthalmology Centers during the COVID-19 Pandemic.

J Ophthalmic Vis Res 2020 Jul-Sep;15(3):438-441. Epub 2020 Aug 6.

Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

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http://dx.doi.org/10.18502/jovr.v15i3.7466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7431722PMC
August 2020

Assessing the abilities of senior otolaryngology residents and graduated otolaryngologists in recognizing skull base elements in axial CT scan: proposing a new method for differentiating superior orbital fissure and optic canal.

Eur Arch Otorhinolaryngol 2021 Jan 19;278(1):203-209. Epub 2020 Jun 19.

Otorhinolaryngology Research Center, Tehran University of Medical Sciences, Amir Alam Hospital, Sa'adi Street, PO Box 14155-6446, Tehran, Iran.

Background And Objectives: The aim of this study was to evaluate the ability of recognizing some important elements of the skull base in axial CT-scan cuts, including the optic canal (OC), superior orbital fissure (SOF), vidian canal (VC), foramen rotundum (FR), jugular foramen (JF) and hypoglossal canal (HC).

Methods: In this study, 25 otolaryngology residents and 25 recently graduated otolaryngologists were evaluated in terms of their recognition of skull base elements, using 30 axial CT-scan cuts. Two months later, the exam related to skull base CT scans was taken in groups after a brief anatomy courses for otolaryngology residents.

Results: The percentage of correct answers from otolaryngology residents regarding OC, SOF, VC, FR, JF, and HC in the first exam were 74 ± 26, 47 ± 34, 65 ± 30, 41 ± 38, 58 ± 26, and 68 ± 32, respectively. The correct answer for each element was similar between groups, and the differences were not statistically significant (p > 0.05). p value for the differences observed regarding the percentage of correct answers for the second exam between trained otolaryngology residents and recent otolaryngology graduates regarding OC and JF was no significant (p > 0.05) but significant for the other elements with better result in trained otolaryngology residents and most for SOF (p > 0.0001).

Conclusion: This study showed that the ability of recognition for the mentioned elements in axial CT-scan cuts was low among otolaryngology residents and graduated otolaryngologists. The proposed novel method for distinguishing SOF from OC had a powerful and long-lasting effect on trainee.
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http://dx.doi.org/10.1007/s00405-020-06108-2DOI Listing
January 2021

The analgesic effect of metformin on paclitaxel-induced neuropathic pain model in rats: By considering pathological results.

J Cancer Res Ther 2020 Jan-Mar;16(1):34-39

Department of Pathology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.

Background And Objective: Metformin (MET) has been used as an antidiabetic agent for type II diabetes. At the same time, recent researches have shown that the clinical improvement of MET is useful for nerve damage. In this study, we investigated the analgesic effect of MET in paclitaxel (PAC)-induced neuropathic pain.

Materials And Methods: Forty-two adult, female rats, Wistar strain weighing 220 ± 10 g were randomly divided into 5 experimental groups. PAC was intraperitoneally (IP) administered (2.0 mg/kg) for 4 groups every other day (0, 2, 4, and 6 days). By the 30 day, MET (100, 200, and 400 mg/kg) was administered to 4 groups. Before and after treatment, basal pain threshold values were measured with Randall-Selitto analgesiometer test. At the end of experiment, pathological values were measured in selected regions including brain (motor cortex, M1), spinal cord (L4-L5), sciatic nerve, and muscle.

Results: According to our results, PAC-induced neuropathic pain reached to highest level at 14 day. Four hundred milligram/kilogram concentration of MET remarkably decreased PAC-induced neuropathic pain. On the other hand, pathologic features have shown that PAC had significant pathological change in the brain and spinal cord while in the peripheral nerves and muscles had not shown any pathological change.

Conclusion: The pathological results of the current study for the first time demonstrated that MET beside of its antidiabetic effects reversed neuropathic pain induced by PAC. Consequently, this research can be promising for cancer patients that suffering from neuropathic pain induced by anticancer drugs.
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http://dx.doi.org/10.4103/jcrt.JCRT_1455_16DOI Listing
October 2020

Perfusion Computed Tomography Scan Imaging in Differentiation of Benign from Malignant Parotid Lesions.

Int Arch Otorhinolaryngol 2020 Apr 4;24(2):e160-e169. Epub 2019 Nov 4.

Department of Otorhinolaryngology, Otorhinolaryngology Research Center, Tehran University of Medical Sciences, Tehran, Iran.

 The most common site of salivary gland tumors is the parotid gland. Computed tomography (CT), magnetic resonance imaging (MRI), and sonography are imaging modalities to differentiate benign from malignant parotid tumors.  The aim of this study is the evaluation of the diagnostic value of perfusion CT for differentiating histological categorization of benign and malignant parotid tumors.  A total of 29 patients with parotid neoplasms were enrolled in this study. Mean age and all CT perfusion variables (gradient and permeability, blood flow [BF], blood volume [BV], mean transit time [MTT], permeability surface [PS], maximum intensity projection [MIP], time-density curve [TDC], and time to peak [TTP]) were compared among three groups (malignant tumors [MTs], Warthin's tumor [WT] and pleomorphic adenomas [PA]).  The mean age of the patients was 55.9 ± 14.1 (26-77), and 15 of them were male (51.7%). Eleven lesions were PAs [37.9%], 8 lesions were WTs (27.6%0 and 10 lesions (34.5%) were MTs (6 acinic cell carcinomas [ACCs], 3 adenocystic carcinomas [AdCCs], and 1 mucoepidermoid carcinoma [MEC]). The mean age of the patients with WTs was 62 ± 7.5 years; 52 ± 14.2 for patients with Pas, and 55.2 ± 17.2 for those with MTs (  = 0.32). The mean MIP was 122.7 ± 12.2 in WT, while it was 80.5 ± 19.5 in PA, and 76.2 ± 27.1 in MTs (  < 0.001); The mean MIP for WT was higher than for PAs and MTs; the values of MTs and PAs were not statistically different. The average of BF, BV, and curve peak were higher in WTs in comparison with the other two groups, and curve time 2 and TTP were higher in PAs in comparison with MTs.  Based on this study, perfusion CT of the parotid gland and its parameters can distinguish between benign and malignant parotid masses.
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http://dx.doi.org/10.1055/s-0039-1697005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6828566PMC
April 2020

Coronary CT Angiography and Dual-Energy Computed Tomography in Ischemic Heart Disease Suspected Patients.

Arch Iran Med 2019 07 1;22(7):376-383. Epub 2019 Jul 1.

Department of Radiology, Amiralalm Hospital, Tehran University of Medical Sciences, Tehran, Iran (C. O).

Background: Advanced computed tomography (CT) scanners enable concurrent assessment of coronary artery anatomy and myocardial perfusion. The purpose of this study was to assess dual-energy CT images in a group of patients suspected for ischemic heart disease and to evaluate agreement of cardiac computed tomography perfusion (CTP) images with CT angiography results in a single dual-energy computed tomography (DECT) acquisition.

Methods: Thirty patients (mean age: 53.8 ± 12.9 years, 60% male) with angina pectoris or atypical chest pain, suspected for ischemic heart disease, were investigated using a 384-row detector CT scanner in dual-energy mode (DECT). Firstly, resting CTP images were acquired, and then from the same raw data, computed tomography angiography (CTA) studies were reconstructed for stenosis detection. CT-based dipyridamole-stress myocardial perfusion imaging was then performed in patients who exhibited coronary stenosis >50% or had myocardial bridge (MB). A color-coded iodine map was used for evaluation of myocardial perfusion defects using the 17-segment model. Two independent blinded readers analyzed all images for stenosis and myocardial perfusion defects. Different myocardial iodine content (mg/mL) was calculated by parametric tests. The kappa agreement was calculated between results of two methods in cardiac scans.

Results: All 30 CT angiograms were evaluated and assessment ability was 100% for combined CTA/CTP. According to the combined CT examination, 17 patients (56.7%) exhibited significant coronary stenosis and/or deep MB (DMB). A total of 510 myocardial segments and 90 vascular territories were analyzed. Coronary CTA demonstrated significant stenosis in 22 vessels (24.4% of all main coronary arteries) among 12 patients (40%), DMB in 6 vessels (6.7% of all main coronary arteries) in 17 out of 30 patients (56.7%). Twenty-eight out of 90 vascular territories (31.1%) and 41 out of 510 segments (8%) showed reversible perfusion defects on stress DECT. Kappa agreement between CTA and CTP results in whole heart was 0.79 (95% confidence interval=0.57-1). There were significant differences in mean iodine concentration between ischemic (0.59 ± 0.07 mg/mL) and normal segments (2.2 ± 0.15) with P < 0.001.

Conclusion: Agreement of CTA and CTP in whole heart and in LAD considering DMB and significant CAD together were good to excellent; however, considering sole pathologies, most of the agreements were weak (<0.5). DECT with iodine quantification may provide a valuable method in comparison with previous methods for identifying both coronary stenosis and myocardial ischemia.
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July 2019

Effect of metformin/irinotecan-loaded poly-lactic-co-glycolic acid nanoparticles on glioblastoma: in vitro and in vivo studies.

Nanomedicine (Lond) 2018 07 20;13(13):1595-1606. Epub 2018 Jul 20.

Department of Medical Pharmacology, Faculty of Medicine, Atatürk University, 25240, Erzurum, Turkey.

Aim: The present study was designed to evaluate the effects of irinotecan hydrochloride (IRI)- or metformin hydrochloride (MET)-loaded poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for the treatment of glioblastoma multiforme using in vitro neuron and U-87 MG glioblastoma cell cultures and in vivo animal model.

Methods: The cytotoxic and neurotoxic effects of pure drugs, blank NPs and MET- and IRI-loaded PLGA NPs were investigated in vitro (using methylthiazolyldiphenyl-tetrazolium bromide assay) and in vivo (using Cavalieri's principle for estimation of cancer volume).

Results: 1 and 2 mM doses of MET and MET-loaded PLGA NPs, respectively, significantly reduced the volume of extracted cancer.

Conclusion: Consequently, MET- and IRI-loaded PLGA NPs may be a promising approach for the treatment of glioblastoma multiforme.
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http://dx.doi.org/10.2217/nnm-2017-0386DOI Listing
July 2018

Assessing the Relation of Epicardial Fat Thickness and Volume, Quantified by 256-Slice Computed Tomography Scan, With Coronary Artery Disease and Cardiovascular Risk Factors.

Arch Iran Med 2018 03 1;21(3):95-100. Epub 2018 Mar 1.

Department of Radiology, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran.

Background: This study aimed to investigate the association between epicardial adipose tissue (EAT) and coronary artery disease (CAD) as well as cardiovascular risk factors.

Methods: Complete medical records of subjects were reviewed and cardiovascular risk factors were recorded. Epicardial fat volume (EFV) and epicardial fat thickness (EFT) were measured using digital volumetry of acquired images using a 256-slice CT-scanner. Calcium score was measured using Agatston method in non-contrast images. After contrast administration, bolus-tract images were obtained. Coronary arteries were assessed using reconstructed images in arterial phase of contrast-enhanced images. EFV and EFT measurements were compared to computed tomography angiography (CTA) findings of coronary arteries.

Results: A total of 269 patients (Mean age: 55.5 ± 12.1, 44% female) were included. Higher means of EFT and EFV were associated with coronary artery stenosis. However, the correlation coefficients of the arterial stenosis with EFT and EFV were weak. EFV and EFT had a significant association with age (P < 0.001, P < 0.001 respectively), body mass index (BMI) (P < 0.001, P < 0.001 respectively) and hypertension (P < 0.016, P < 0.003 respectively). Diabetes mellitus (DM) and hyperlipidemia were not significantly associated with EFV (P = 0.069 and 0.639 respectively) and EFT (P = 0.103 and 0.366 respectively). EFV and EFT showed a weak correlation coefficient with calcium scoring (Spearman correlation coefficients: 0.26 and 0.22 respectively, both P < 0.001). In multivariate logistic regression models considering coronary stenosis as dependent variable and EFV, EFT and other CAD risk factors as independent variables, EFV and EFT did not show significant P values and were omitted from the model by other CAD risk factors.

Conclusion: Increased EFV and EFT are associated with CAD, age, BMI and hypertension. However, no remarkable association was found between them and calcium score, hyperlipidemia or DM. These variables could weakly predict CAD in univariate models but they are not independent predictive factors for CAD in multivariate models consisting of other CAD risk factors. Hence, EFT and EFV are not independent predictors for CADs when they are considered simultaneously with other CAD risk factors.
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March 2018

PEGylated graphene oxide/Fe3O4 nanocomposite: Synthesis, characterization, and evaluation of its performance as de novo drug delivery nanosystem.

Biomed Mater Eng 2018 ;29(2):177-190

Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.

This paper describes the development of mitoxantrone-loaded PEGylated graphene oxide/magnetite nanoparticles (PEG-GO/Fe3O4-MTX), and investigation of its preliminary drug delivery performance. For this, the GO was synthesized through oxidizing graphite powder, and subsequently carboxylated using a substitution nucleophilic reaction. The carboxylated GO (GO-COOH) was then conjugated with amine end-caped PEG chains by Steglich esterification. Afterward, GO-PEG/Fe3O4 nanocomposite was synthesized through the anchoring of Fe3O4 nanoparticles onto the surface of GO-PEG during the sonication. The biocompatibility and MTX-loading capacity of the synthesized GO-PEG/Fe3O4 nanocomposite were evaluated. The pH dependent drug release behavior and cytotoxicity effect of the MTX-loaded GO-PEG/Fe3O4 nanocomposite were also studied. According to biocompatibility, pH dependent drug release behavior as well as superior physicochemical and biological characteristics of graphene and magnetite nanoparticles, it is expected that the GO-PEG/Fe3O4 nanocomposite may be applied as de novo drug delivery system (DDS) for cancer therapy using both chemo- and photothermal therapy approaches.
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http://dx.doi.org/10.3233/BME-171721DOI Listing
August 2018

Diagnostic Efficacy of Coronary Artery Three-Dimensional Steady-State Free Precession Magnetic Resonance Angiography in Comparison with Invasive Coronary Angiography for Detecting Coronary Artery Disease.

Arch Iran Med 2017 May;20(5):314-319

Amiralam Hospital, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: To assess the diagnostic value of three-dimensional steady-state free precession magnetic resonance angiography (3D-SSFP MRA) for detecting coronary artery disease (CAD).

Materials And Methods: Patients suspected of CAD based on clinical evaluation, underwent invasive coronary angiography (CAG) and Cardiac MRA (CMRA). Collected data in favor of any CAD findings in CMRA were compared to CAG results as the standard diagnostic method in CAD detection. Analysis was performed on per-patient, per-vessel and per-segment bases.

Results: A total of 30 patients (mean age: 43 ± 10 years, 19 men) were enrolled for analysis. On per-patient analysis, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under receiver operator characteristic (ROC) curve of CMRA for detection of coronary artery stenosis were 100% (CI95%: 75% - 100%), 50% (CI95%: 18% - 81%), 73.33% (CI95%: 46% - 90%), 100% (CI95%: 47% - 100%) and 0.827, respectively. On per-vessel analysis, CMRA had a sensitivity of 89.29% (CI95%: 71%-97%), specificity of 80.56% (CI95%: 63% - 91%), PPV of 78.13% (CI95%: 60% - 90%), NPV of 90.63% (CI95%: 74% - 98%) and area under ROC curve of 0.845. On per-segment analysis, sensitivity, specificity, PPV and NPV of CMRA for segmental stenosis detection were 77.78% (CI95%: 60% - 89%), 87% (CI95%: 81% - 92%), 62% (CI95%: 46% - 76%), and 93.89% (CI95%:  88% - 97%), respectively. Area under ROC curve was 0.835 on per-segment analysis.

Conclusion: 3D SSFP CMRA provides a promising non-invasive diagnostic tool for assessing coronary artery disease.
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http://dx.doi.org/0172005/AIM.0010DOI Listing
May 2017

Pretreatment Evaluation of Glioma.

Neuroimaging Clin N Am 2016 Nov 3;26(4):567-580. Epub 2016 Sep 3.

Division of Neuroradiology, Department of Radiology, Amiralam Hospital, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

Glioma is considered the most common type of primary central nervous system (CNS) tumor. Imaging is crucial for diagnosis, characterization, grading, and therapeutic planning of CNS gliomas. Along with a brief description of conventional computed tomography and magnetic resonance imaging techniques, this article reviews the ever-developing role of modern imaging techniques in preoperative management of CNS gliomas. It discusses current clinical applications, promising features, and limitations of each imaging method.
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http://dx.doi.org/10.1016/j.nic.2016.06.006DOI Listing
November 2016

Cardiac autonomic neuropathy measured by heart rate variability and markers of subclinical atherosclerosis in early type 2 diabetes.

ISRN Endocrinol 2012 4;2012:168264. Epub 2012 Dec 4.

Elderly Health Research Center, Endocrinology & Metabolism Research Center, Tehran University of Medical Sciences, Dr Shariati University Hospital, North Kargar Avenue, Tehran, Iran ; Tehran Heart Center, Tehran University of Medical Sciences, North Kargar Avenue, Tehran, Iran.

Cardiac autonomic neuropathy (CAN) is a critical complication of type 2 diabetes mellitus (T2DM). Heart rate variability (HRV) is a noninvasive tool to assess cardiac autonomic function. We aimed to evaluate whether CAN is associated with increased risk of atherosclerosis in T2DM. A total of 57 diabetic and 54 nondiabetic subjects, free of coronary heart disease, were recruited. Carotid intima media thickness (CIMT), coronary calcium score (CAC), and brachial Flow Mediated Dilation (FMD) were measured. Heart rate variability and vagal components of autonomic function were determined. Significant reduction of normalized HF power (P < 0.05) and total power (P < 0.01) was observed in T2DM. CIMT and CAC scores were significantly higher while FMD was significantly lower in diabetics (P < 0.01 for all). Median HbA(1c) levels were significantly higher in diabetics. CIMT was inversely and independently associated with total power both in diabetics and controls (P < 0.01 for both groups). There was also an inverse association between total power and median HbA(1c). Autonomic dysfunction, especially parasympathetic neuropathy, was present since early-stage T2DM. This was related to subclinical atherosclerosis. Early detection of cardiac autonomic neuropathy can help us detect the development of atherosclerosis earlier in T2DM to prevent unfavorable outcomes.
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http://dx.doi.org/10.5402/2012/168264DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3521488PMC
December 2012

Efficacy of transarterial chemoembolization on lesion reduction in colorectal liver metastases.

Acta Med Iran 2012 ;50(8):535-40

Department of Radiology, Advanced Diagnostic and Interventional Radiology Research Center, Medical Imaging Center, Imam Khomeini Hospital, Tehran University of medical Sciences, Tehran, Iran.

Following failure of systemic chemotherapy, transarterial chemoembolization (TACE) is an available method to control unresectable liver metastases from colorectal carcinoma (CRC). The aim of present study was to evaluate the efficacy of chemoembolization for inoperable metastatic liver lesions from CRC. Forty-five CRC patients with liver metastases resistant to systemic chemotherapy were enrolled in our study. For each patient, three session of TACE were conducted with 45 days interval. A combination of mitomycin, doxorubicin, and lipiodol were used for TACE. A tri-phasic computed tomography scan and biochemical laboratory tests were performed for all patients at baseline and 30 days after each TACE. Image analysis included measurement of lesion diameters as well as contrast enhancement. Eleven patients deceased before completing three session and the final analyses were performed on the remaining 34 patients. Evaluation of a total 93 lesions in all patients after chemoembolization sessions revealed a 25.88% reduction in anteroposterior (AP) diameter, 33.92% transverse (T) diameter, and 42.22% in product of APxT diameter of lesions (P<0.001 for all instances). CT scan showed a total disappearance of 33% of lesions and evident reduction in contrast enhancement in 16% of them. There were no changes in contrast enhancement in 51% of lesions. Evaluation of single largest lesion in each patient revealed 57.32% reduction in AP diameter, 59.66% in T diameter, and 62.17% in product of APxT diameters (P<0.001 for all diameters). TACE offers a viable option for CRC patients with unresectable liver metastases by significantly reducing lesion size and contrast enhancement.
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April 2013

Diagnostic performance of multislice CT coronary angiography in the assessment of significant coronary artery disease.

Acta Med Iran 2012 ;50(1):31-6

Department of Radiology, Rejaee Cardiovascular Research Center, Tehran University of Medical Sciences, Iran.

The use of noninvasive assessment tools such as multi-slice CT coronary angiography (MSCT-CA-CA) is recently considered mainly because it offers safety, patient convenience, and faster performance. The aim of the present study was to determine the ability of MSCT-CA-CA for the detection of significant stenoses in the coronary arteries, in comparison to conventional invasive coronary angiography (ICA). A total of 58 consecutive patients who were candidate for coronary angiography, with the diagnosis of acute coronary syndrome, from September 2006 to March 2006 were entered into the study. They underwent both coronary MSCT-CA-CA and ICA. The findings of each coronary segment were compared to MSCT-CA-CA in comparison with ICA. Based on artery analysis, sensitivity and specificity of MSCT-CA for the detection of involvement in RCA were 90.0% and 92.8%, in LAD were 71.8% and 92.9% and in LCX were 67.9% and 92.6%, respectively. On a per-segment basis, the sensitivity of MSCT-CA in the detection of injured segments ranged between 33.3% (for segment 11) and 100% (for segments 1, 2 and 12). Also, specificity ranged from 63.6% (for segment 15) and 98.1% (for segment 6). The presence of hypertension, hyperlipidemia, and smoking led to the reduction of the specificity and accuracy of MSCT-CA, whereas history of diabetes mellitus could increase the specificity and accuracy of this tool. MSCT-CA has high diagnostic performance in the assessment of significant coronary artery disease. Risk factors for coronary artery disease may influence this performance.
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May 2012

Arterial damage accompanying supracondylar fractures of the humerus.

Trauma Mon 2012 Jan 15;16(4):160-3. Epub 2012 Jan 15.

Gilan University of Medical Science, Rasht, IR Iran.

Background: Arterial damage is sometimes associated with supracondylar fractures of the humerus. Diagnosis and careful management of the fracture and arterial repair is crucial.

Objectives: The aim of this study was to determine the prevalence and outcome of supracondylar fractures of the humerus with signs and symptoms of limb ischemia, before and after arterial decompression or arterial reconstruction.

Materials And Methods: From September 2004 to July 2010, 225 consecutive patients with supracondylar fracture of the humerus were prospectively recruited.

Results: From among 75 cases with Gartland type III fractures, 22 were found to have vascular injury.. Of the 22 cases with vascular injury, 7 patients underwent arterial reconstruction. The other 15 received arterial decompression. All patients had a satisfactory outcome.

Conclusions: A high level of suspicion and careful clinical evaluation leading to an early diagnosis and management of vascular injury accompanying supracondylar fracture is very important to prevent unnecessary sequelae ranging from limb claudication, and compartment syndrome to more severe complications like Volkmann's contracture and even limb loss.
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http://dx.doi.org/10.5812/kowsar.22517464.3273DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3989565PMC
January 2012
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