Parham Geramifar

Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran

[ 1 ] - Factors influencing the pattern and intensity of myocardial 18F-FDG uptake in oncologic PET-CT imaging

Introduction:Myocardial 18F-FDG uptake is highly variable in oncologic whole body 18F-FDG PET/CT studies, ranging from quite intense to minimal distribution. Intense or heterogeneous myocardial 18F-FDG uptake is undesirable as it may interfere with the visual or quantitative evaluation of tumoral invasion and metastases in pericardium, myocardiu...

[ 2 ] - How to manage patients with undetectable thyroglobulin but thyroid residue after radioiodine ablative therapy in differentiated thyroid carcinoma, retreatment or observation?

Introduction:Differentiated thyroid carcinoma (DTC) follow-up after thyroidectomy and radioiodine-ablation is performed mainly by thyroglobulin (Tg), diagnostic iodine-131 whole body scan (DxWBS) and sonography. Some patients with undetectable Tg have thyroid-bed uptake after ablation in whom decision making regarding the need for retreatment is still controversial. Me...

[ 3 ] - Performance comparison of four commercial GE discovery PET/CT scanners: A monte carlo study using GATE

  Combined PET/CT scanners now play a major role in medicine for in vivo imaging in oncology, cardiology, neurology, and psychiatry. As the performance of a scanner depends not only on the scintillating material but also on the scanner design, with regards to the advent of newer scanners, there is a need to optimize acquisition protocols as well as to compare scanner ...

[ 4 ] - Preclinical evaluation of 68Ga-MAA from commercial available 99mTc-MAA kit

99mTc-Macroaggregated Albumin (99mTc-MAA) has been used as a perfusion agent. This study described development of the 68Ga-MAA via commercially available kits from Pars-Isotopes Company as a 99mTc-MAA kit. 68Ge/68Ga generator was eluted with suprapure HCl (0.6 M, 6 mL) in 0.5 mL fractions. The two fractions with the highest 68GaCl3 activity were generally used for labeling purposes. After label...

[ 5 ] - Preclinical evaluation of 68Ga-MAA from commercial available 99mTc-MAA kit

99mTc-Macroaggregated Albumin (99mTc-MAA) has been used as a perfusion agent. This study described development of the 68Ga-MAA via commercially available kits from Pars-Isotopes Company as a 99mTc-MAA kit. 68Ge/68Ga generator was eluted with suprapure HCl (0.6 M, 6 mL) in 0.5 mL fractions. The two fractions with the highest 68GaCl3 activity were generally used for labeling purposes. After label...

[ 6 ] - Design and performance evaluation of spheroid geometry for brain PET scanner using Monte Carlo modeling

Introduction: There has been a curiosity about the spheroid geometry for PET scanners developments since several years ago, therefore in this study, we are aiming to evaluate the performance of this geometry and compare its performance with cylindrical geometry using Monte Carlo simulation. Methods: We simulated a spheroid geometry with a radius of 199 mm...

[ 7 ] - Diagnostic efficiency of 68Ga-DOTATATE PET/CT as compared to 99mTc-Octreotide SPECT/CT and conventional morphologic modalities in neuroendocrine tumors

Objective(s): In view of somatostatin receptor (SSR) expression on cell membranes of the majority of neuroendocrine tumors (NETs), functional imaging exploiting analogs of SSR alongside the anatomical imaging is the mainstay of this diagnostic modality. In this prospective study, we assessed and directly compared the diagnostic parameters of 68Ga-DOTATATE PET/CT and 99...

[ 8 ] - The effect of incorporating the quantitative analysis besides visual assessments of 18F-FDG brain PET images for the localization of epileptogenic zones

Introduction: FDG Brain PET is a valuable paraclinical tool for presurgical assessments of patients suffering from refractory epilepsy. By the widespread accessibility of PET, recognizing the functional lesions has become a current practical method especially in preoperative evaluations of the partial epilepsy disorders. The aim of our study was to assess the impact of quantit...

[ 9 ] - Rabbit internal dosimetry for iodine-131 using GATE Monte Carlo simulation code: a preclinical trial

Introduction: One of the main concerns in administration of radiotracers, especially in therapeutic arm, is the amount of delivered dose to the different organs. Individual variations of anatomy, physiology and underlying pathology in the patients lead to alteration of administered activity. In the current study we preclinically applied internal dosimetry using an animal mod...

[ 10 ] - Validation and evaluation of a GATE model for MAMMI PET scanner

Introduction:MAMMI is a dedicated PET based on high resolution detectors placed close to the breast. In this study, we presented a GATE model for the simulation of MAMMI scanner and model its performance of the MAMMI based on an adaptation of the NU 4-2008 NEMA standard.  Methods:A detailed of geometry MAMMI system that uses scintillation crystals coupled...

[ 11 ] - Preclinical study of a new 177Lu-labeled somatostatin receptor antagonist in HT-29 human colorectal cancer cells

Objective(s): Somatostatin receptor-positive neuroendocrine tumors have been targeted using various peptide analogs radiolabeled with therapeutic radionuclides for years. The better biomedical properties of radioantagonists as higher tumor uptake make these radioligands more attractive than agonists for somatostatin receptor-targeted radionuclide therapy. In this study...