Seyed Rasoul Zakavi
Nuclear Medicine Research Center, Mashhad University of Medical Sciences
[ 1 ] - Comparison of Treatment Response Achieved by Tablet Splitting Versus Whole Tablet Administration of Levothyroxine in Patients with Thyroid Cancer
Objective(s): TSH suppression by Levothyroxine consumption is a mainstay of thyroid cancer treatment. Tablet-splitting is a worldwide approach in dose adjustment in patients. However, it is highly recommended to evaluate the validity of tablet splitting for each distinctive drug by clinical trials before routinely using tablet halves in clinical practice. In this study we compared the effect of...
[ 2 ] - Extraosseous accumulation of Technetium-99m-Methyl Diphosphonate (99mTc-MDP) in a child with ALL: A Case Report
Extraosseous accumulation of technetium-99m-methyl diphosphonate (99mTc-MDP) on bone scan is not common. This phenomenon is often attributed to abnormality of calcium metabolism and has been reported in a variety of conditions including metabolic diseases and malignancies. A five years old boy is presented here, who was admitted to the pediatric emergency suffering from fatigue, respiratory sym...
[ 3 ] - Clinical value and severity of myocardial perfusion defects in asymptomatic diabetic patients with negative or weakly positive exercise treadmill test
Objective: Although coronary artery disease (CAD) is the leading cause of death in type 2 diabetic patients, it is frequently asymptomatic. Myocardial perfusion imaging (MPI) is reported to show ischemia in a significant number of asymptomatic diabetic patients. We studied the prevalence and severity of myocardial perfusion defects in asymptomatic diabetic patients and its clinical impact. Meth...
[ 4 ] - Treatment efficacy of 153Sm-EDTMP for painful bone metastasis
Introduction: Involvement of the skeleton can cause an excruciating pain in two-thirds of terminal patients with a history of malignancy. Due to several limitations of other therapies, such as analgesics, bisphosphonates, chemotherapy, hormonal therapy and external beam radiotherapy; bone-seeking radiopharmaceuticals have an important role in palliation of pain from bone metastases. Although th...
[ 5 ] - Ectopic papillary thyroid carcinoma in the mediastinum without any tumoral involvement in the thyroid gland. A Case report
Ectopic thyroid tissue results from abnormal embryologic development and migration of the thyroid gland. True malignant transformation in ectopic thyroid tissue is extremely rare and is always diagnosed after surgical excision of the lesion by pathology examinations. There are well-documented cases of ectopic thyroid cancer while primary tumoral lesion occurs in the orthotopic thyroid, but only...
[ 6 ] - A study on differentiation of extra-cardiac activity by Slit Slat collimation in Single Photon Emission Computed Tomography
Introduction: Myocardial perfusion SPECTby 99mTc-Sestamibi and 99mTc-Tetrofosmin radiopharmaceuticals usually presents a false significant increase in the radiotracer uptake in the inferior myocardium due to the uptake in organs such as liver, bowel, stomach and biliary system. The present study evaluated a suitable Slit angle for differentiating extra-car...
[ 7 ] - Efficacy of radiosynovectomy in the treatment of chronic knee synovitis: Systematic review and meta-analysis
Introduction: Knee joints are commonly involved with various inflammatory and non- inflammatory rheumatic diseases. Radiosynovectomy is being used as a local therapeutic option to alleviate pain and swelling in involved joints. The present study evaluated the effectiveness of radiosynovectomy for treatment of chronic knee synovitis. Methods: Through a search of Medline and SCOPUS with (Radiosy...
[ 8 ] - Which complaint has the most clinical effect on quality of life of thyroid cancer survivors in long term follow up?
Introduction: Differentiated thyroid cancer (DTC) is the most common endocrine malignancy. This malignancy generally has an excellent prognosis with more than 90% long term survival. Consequently, life quality improvement is the first priority especially in the young DTC survivors. In classic management of a new DTC patient, each therapeutic modality can significantly induce morbidities. In the...
[ 9 ] - Sentinel node mapping in vulvar cancers: report of two cases and literature review
Vulvar cancer is a rare gynecological malignancy with mainly lymphatic spread. Sentinel node mapping plays an important role in the management of this gynecological malignancy. In the current study, we reported our experience in sentinel node mapping of vulvar cancer and review the literature accordingly. Since the introduction of sentinel node mapping to the surgical oncology community of our ...
[ 10 ] - Gated 99mTc-MIBI myocardial perfusion SPECT in patients with right bundle branch block but without evidence of coronary artery disease
Introduction: We aimed to investigate the effect of right bundle branch block (RBBB) on perfusion and functional parameters in dipyridamole stress/rest Tc99m-MIBI gated myocardial perfusion SPECT (GSPECT) which may be helpful in interpretation of myocardial perfusion imaging. Methods: We studied 73 patients with low pre-test likelihood of coronary artery disease in two groups: 38 patients wit...
[ 11 ] - Sentinel node detection failure due to defective labeling and large particle size of Tc-99m antimony sulfide colloid
Introduction: Many radiotracers have been used for sentinel node mapping with acceptable results. The main difference between these radiotracers is the particle size. In the current study, we reported defective labeling of Tc-99m antimony sulfide colloid which resulted in large particle size. Methods: Tc-99m-Antimony sulfide colloid was used for axillary sentinel n...
[ 12 ] - Can gallbladder ejection fraction measured by fatty meal cholescitigraphy diagnose chronic cholecystitis?
Introduction: Despite presence of a body of evidence in support of high accuracy of cholecystokinin cholescintigraphy (CCK-CS) , for diagnosis of chronic cholecystitis(CC) , some authors have claimed that gallbladder ejection fraction (GBEF) has poor predictive diagnostic values. The purpose of this study was to determine if there is any difference in GBEF between...
[ 13 ] - Comparison between early and delayed images of 67Ga scintigraphy for evaluation of recurrent lymphoma
Introduction: Despite widespread use of 67Gallium for lymphoma evaluation, timing of imaging after injection is a matter of controversy and to the extent of our knowledge no direct comparison has been made between early and delayed gallium images. We aimed to compare 24 and 48 hours post injection planar gallium imaging for evaluation of lymphoma recurrence. Methods: 255 pa...
[ 14 ] - Echocardiographic left ventricular functional changes in acute hypothyroidism vs. subclinical hyperthyroidism in patients with differentiated thyroid carcinoma
Introduction: In order to assess echocardiographic left ventricular functional indices in patients with differentiated thyroid carcinoma (DTC), after L-T4 withdrawal (short-term overt hypothyroidism) and during TSH suppressive therapy, we have evaluated cardiac hemodynamics in a single cohort study. Methods: 24 patients with DTC were studied in two phases: 1: at least 4 weeks after L-T4 withd...
[ 15 ] - Coronary artery calcium (CAC) score – a prognostic tool in coronary artery disease?
Introduction: The aim of this study was to evaluate the impact of measurement of coronary artery calcification score (CAC) in patients with suspected coronary artery disease (CAD) and a normal myocardial perfusion scan. Methods: In a prospective study we measured the calcium score of 74 patients (29 m, 45 f, mean age 58.7 (m) and 64.4 (f)) with suspicion of CAD and a normal perfusion scan. In ...
[ 16 ] - Sentinel lymph node biopsy in melanoma patients: An experience with Tc-99m antimony sulfide colloid
Introduction: Sentinel lymph node biopsy is the standard procedure for lymph node staging in intermediate thickness melanoma. In Iran, this procedure has not been addressed sufficiently. In this study, we report our experience in this area. Methods: Ten consecutive patients with intermediate thickness melanoma where included in our study. 1.5 mCi of Tc-99m antimony...
[ 17 ] - Sensitivity of gallium scintigraphy for evaluation of recurrent lymphoma: Comparison of planar and SPECT imaging
Introduction: Although PET scanning using F-18[FDG] is considered the superior radiotracer for tumnor imaging, Gallium-67 is still in use for some malignancies such as lymphoma and hepatoma. One of the strategies to improve the diagnostic accuracy of Gallium is to perform SPECT which is reported to be more sensitive compared to planar imaging. In this study we compa...
[ 18 ] - Incidental change in photopeak during a dynamic renal scan
Abstract is NOT available
[ 19 ] - Minimally invasive radio-guided surgery for hyperparathyroidism: an experience with Tc-99m Sestamibi
Introduction: Radio-guided parathyroid surgery along with other minimally invasive surgeries constitutes the main surgical treatment procedures for different kinds of hyperparathyroidism. In this article we have reported our experience of radio-guided parathyroid surgery using Tc-99m sestamibi. Methods: Ten patients with hyperparathyroidism included in our study. ...
[ 20 ] - Evaluation of attenuation correction process in cardiac SPECT images
Introduction: Attenuation correction is a useful process for improving myocardial perfusion SPECT and is dependent on activity and distribution of attenuation coefficients in the body (attenuation map). Attenuation artifacts are a common problem in myocardial perfusion SPECT. The aim of this study was to compare the effect of attenuation correction using different a...
[ 21 ] - The need for skin pen marking for sentinel lymph node biopsy: A comparative study
Introduction: There is a consensus in the literature that sentinel lymph node biopsy is the standard procedure for axillary staging in early stage (I and II) breast cancer patients. Usually during lymphoscintigraphy, the location of the sentinel lymph node is marked on the skin by an indelible ink. In this study we evaluated this issue in our patients. Methods: 40 ...
[ 22 ] - Diffuse bilateral breast uptake on the myocardial perfusion SPECT of a nursing female
Bilateral diffuse intense breast uptake was noted in a 40 year old female who was evaluated with Tc-99m sestamibi (MIBI) myocardial perfusion scan for possible ischemia. She was breast feeding her 1.5 year old child. The intense uptake in the breasts was superimposed on the apical and anteroapical regions of the myocardium and caused interpretation problem. We recom...
[ 23 ] - Delayed imaging for detection of Meckel's diverticulum in Tc-99m pertechnetate scintigraphy
Tc-99m pertechnetate scintigraphy is the modality of choice for diagnosis of Meckel's diverticulum. Interpretation of Meckel's scan identifies a focal area of radiopharmaceutical uptake in the anterior abdomen similar to normal gastric mucosa. The activity must be of the same pattern and intensity as gastric uptake. We present a 13-year-old patient with gastrointest...
[ 24 ] - Normal values of left ventricular functional indices in gated 99mTc-MIBI myocardial perfusion SPECT
Introduction: Although left ventricular(LV) function parameters measured by gated myocardial perfusion SPECT (GSPECT) have been validated, experimental data have revealed that the calculated the LV function parameters using GSPECT are affected by patient populations as well as particular acquisition and processing conditions. We tried to determine the normal values ...
[ 25 ] - Evaluation of the role of system matrix in SPECT images reconstructed by OSEM technique
Introduction: Ordered subset expectation maximization (OSEM), is an effective iterative method for SPECT image reconstruction. The aim of this study is the evaluation of the role of system matrix in OSEM image reconstruction method using four different physical beam radiation models with three detection configurations. Methods: SPECT was done with an arc of 180 deg...
[ 26 ] - Radioiodine D amino acids labeling of Rituximab, a new method for enhancing the radiopharmaceutical targetingand biostability
Introduction: Radioimmunotherapy (RIT) is a very promising new therapy for the treatment of recurrent B-Cell non-Hodgkin's lymphoma (NHL). Iodine-131 is the most frequently used nuclide in clinical RIT, but its usefulness has been limited by dehalogenation of monoclonal antibodies labeled via conventional methods. To circumvent this problem, we have synthesized a tr...
[ 27 ] - Diuretic effect on the measurement of differential renal function using 99mTc-DMSA in patients with hydronephrosis [Persian]
Introduction: It has been suggested that calculation of differential renal function (DRF) using 99mTc-DMSA may lead to overestimation of the function of an obstructed kidney. The aim of this study was to evaluate the effect of diuretic administration on the determination of DRF using 99mTc-DMSA scintigraphy in patients with dilated pelvis. Methods: Thirty three patients, aged from 2 month...
[ 28 ] - Complications after dipyridamole infusion in myocardial perfusion SPECT and correlation with homodynamic changes [Persian]
Introduction: In Iran dipyridamole is the main agent used for coronary dilatation before myocardial perfusion SPECT. This study tries to evaluate the side effects after dipyridamole infusion and its relation with hemodynamic changes. Methods: We studied 300 patients who referred to myocardial perfusion scan. The exclusion criteria were: 1) AV block degree 2 or more, 2) Asthma 3) Sick sinu...
[ 29 ] - Assessment of simulated patient motion and its effect on myocardial perfusion SPECT using two reconstruction methods (Filtered Backprojection;FBP and Iterative method) [Persian]
Introduction: Motion of the patient during myocardial perfusion SPECT could potentially results in false perfusion defects. The effect of different reconstruction methods on these artifacts is not studied. Clarification of the relation between the extent, severity and duration of motion with the resultant artifacts may be helpful in designing special soft wares for motion correction. This...
[ 30 ] - Evaluation of thyroid scan with 99mTc-MIBI in selected patients candidate for thyroid surgery [Persian]
Aim: Thyroid scan with sestamibi is used for evaluation of thyroid nodules with the aim of increasing specificity before surgery. In this study we evaluated the role of Sestamibi thyroid scan in candidates for thyroid surgery. Methods and patients: During two years, 37 patients were studied with solitary thyroid nodules, referred for thyroid surgery due to malignant or suspicious FNAB res...
[ 31 ] - Nuclear cardiology in Iran in 2002 [Persian]
Aim: Few nuclear cardiology surveys were published in the literature, mostly from developed countries. The aim of this study is to perform a nuclear cardiology survey in Iran. This may lead to better decision making and programming. Methods and Materials: A questionnaire was sent by mail or e-mail to all nuclear medicine centers in Iran asking for details of nuclear cardiology practice in...
[ 32 ] - Comparison of Thyroid examination, Thyroid scanning and sonography in patients with previous history of radiotherapy of the head for Tinea Capitis [Persian]
Introduction: In spite of large number of studies regarding relation between thyroid cancer and childhood irradiation, contraversy still exists management of these patients. This study tries to find optimal method of thyroid evaluation in this group. Methods and patients: In a recall program using mass media in Khorasan, all patients with childhood irradiation were invited for thyroid eva...
[ 33 ] - Optimization of Gate’s technique for measurement of GFR during routine renal scan [Persian]
Using Gate’s technique for GFR measurement with Gamma camera, the patient is received 5mCi of Tc-99m-DTPA. By this amount of radioactivity, good quality renal scan is not possible. This study tries to optimize Gate’s technique for GFR measurement during routine renal scan (with 10-15 mCi). Methods and materials: Scanning was performed for 60 seconds from samples of Tc-99m with activities ...
[ 34 ] - The optimal time of discountinuing Methimazole before radioiodine therapy [Persian]
Hyperthyroidism is a common disease and one of the best methods for its treatment is radioiodine therapy. Treatment with antithyroid drugs brings patients to euthyroidism before radioiodine therapy. Antithyroid drugs should be discontinued before radioiodine therapy to increase thyroid uptake. The purpose of this study was to determine the optimal time of methimazole (MTZ) discontinuation...
[ 35 ] - Effect of multiple factors on success rate of high dose radioiodine therapy (>150µCi/gr) in 164 patients with hyperthyroidism [Persian]
Background: Radiodine therapy (RIT) for hyperthyroidism is increasingly used as a therapy of choice in most of the patients. Effect of multiple factors on the result of therapy was noted. This study tries to analyze the effect of multiple factors on success rate of RIT. Methods and patients: One hundred and sixty four hyperthyroid patients referred for RIT therapy from 1996-99, were studi...
[ 36 ] - Sensitivity and specificity of thallium-technetium subtraction scan in localization of the parathyroid adenoma [Persian]
Thirty one patients with biologic and clinical diagnosis of hyperparathyroidism were submitted to thalium-technetium scan prior to exploration of the neck. Scan findings were compared with the pathologic results. Surgical exploration of the neck showed a parathyroid adenoma in 24 patients, parathyroid carcinoma in one patient, normal parathyroid in another patient and parathyroid hyperplasia in...
[ 37 ] - A case presentation of parathyroid adenoma and papillary carcinoma of the thyroid [Persian]
A 54 years old female with history of total thyroidectomy for papillary carcinoma, treated with lOOmCi of iodine-131 and negative whole body scans was referred for follow up study. Tl-201 scan revealed an area of radiotracer uptake in the neck region, suggestive of a parathyroid adenoma versus recurrence of thyroid carcinoma. The patient was operated, the parathyroid adenoma was removed. ...
[ 38 ] - Nano Liposomes labeled with 99mTc-HMPAO, A Novel Agent for Blood Pool Imaging
In-vitro labeling of RBC with 99mTc is an intricate procedure and there is always a need foran alternate blood pool imaging agent. The aim of this study was to prepare an effective nanosized liposome (NLs) similar to human RBC for blood pool scintigraphy. This study formulatesPEG-NLs and non-PEG-NLs using film method plus high pressure homogenization technique.Biodistribution studies were perfo...
[ 39 ] - The Role of Nuclear Medicine in The Diagnosis and Management of Solitary Pulmonary Nodules
Solitary pulmonary nodule (SPN) is a frequent finding on the chest x-ray and computed tomography. Nuclear medicine techniques play an important role in the diagnosis and management of SPN. In the current review, we briefly will explain the different nuclear medicine modalities in this regard including positron emission tomography (PET) using 18-F-FDG, and 11-C-Methionine, and single photon em...
[ 40 ] - Nano Liposomes labeled with 99mTc-HMPAO, A Novel Agent for Blood Pool Imaging
In-vitro labeling of RBC with 99mTc is an intricate procedure and there is always a need foran alternate blood pool imaging agent. The aim of this study was to prepare an effective nanosized liposome (NLs) similar to human RBC for blood pool scintigraphy. This study formulatesPEG-NLs and non-PEG-NLs using film method plus high pressure homogenization technique.Biodistribution studies were perfo...
[ 41 ] - Determination of 99Mo contamination in 99mTc elute obtained from 99Mo / 99mTc- generator
Background: 99mTc is a widely used radioisotope in nuclear medicine centers which is obtained by elution from Mo-99/Tc-99m generators. Usually the generators are either supplied by the Iran Atomic Energy Agency or by private companies from foreign countries. In this study we have measured 99Mo contamination in 99mTc elute from different generators in a period of one year. Materials and...
[ 42 ] - Economic Sanctions on Iran and Nuclear Medicine
"It is not a wise choice!", this was the reaction of my father when I applied for nuclear medicine residency program 26 years ago. The old retired officer continued that hi-tech nuclear medicine is dependent on multiple advanced sections that may not be easily available especially in the developing countries. Now he is not alive to see that political misconducts have added fuel to the fire. Glo...
[ 43 ] - Meningioma: A false positive finding of metastasis from prostate adenocarcinoma using 68Ga-PSMA PET/CT scan
A 73-year-old man with history of prostatic adenocarcinoma radical prostatectomy underwent 99mTc-MDP whole-body bone scan and subsequent 68Ga-labeled prostate-specific membrane antigen (PSMA) ligand PET/CT for restaging due to a gradual rise of prostate-specific antigen levels. Whole-body bone scan showed two focal zones of slightly increased uptake in the right fronto-par...
[ 44 ] - Direct comparison of 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT in patients with prostate cancer
Objective(s): 99mTc-PSMA SPECT/CT is a cost effective alternative for 68Ga-PSMA PET/CT. The aim of this study was to directly compare these two techniques in patients with prostate cancer. Methods: 28 man with prostate cancer were studied using 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT in a shor...
[ 45 ] - Detecting aorto-ureteric fistula by 99mTc-Labeled Red Blood Cell SPECT
A 68-year-old male, known case of abdominal aortic dissection and recent aortic stent insertion, presented with gross hematuria. The urologists suspected aoro-ureteric fistula and performed open surgery (ureterolysis). Tc-99m labeled red blood cell (99mTc-RBC) scintigraphy was ordered to confirm the diagnosis and localize the possible aorto-ureteric fisula, Considering sustained gros...
[ 46 ] - Parotid metastasis as the first presentation of papillary thyroid carcinoma
Parotid metastasis originated from papillary thyroid carcinoma is extremely rare, especially as the first presentation of the disease. We present a 70-year-old man with a history of painless swelling in the right side of the neck. He was evaluated for parotid tumor and histopathologic examination revealed a poorly differentiated carcinoma in the parotid gland with suspicion of thyroid origin. T...
[ 47 ] - Breast metastasis from the pancreatic neuroendocrine tumor origin detected by 99mTc-Octreotate scan
A 50 years old woman with history of pancreatic neuroendocrine tumor diagnosed 2 years ago, which has not been surgically removed,was referred to our department for a 99mTc-Octreotate in order to evaluate the somatostatin receptor status. She was treated with regular sandostatin injections and chemotherapy. Her CT scan which was previously performed confirmed lung, adrenal and hepati...
[ 48 ] - Incidental finding of 68Ga-PSMA uptake in covid-19 induced pneumonia
A 68 years old man with prostate carcinoma was referred for 68Ga-PSMA PET/CT scan because of recent significant rise of PSA. He complained of muscle weakness and fatigue, since 3 weeks before the scan, without dyspnea or shortness of breath. In his 68Ga-PSMA-611 PET/CT study, widespread skeletal metastasis, as well as liver involvement were noticed. Also, multiple bilatera...
نویسندگان همکار