Browsing by Author "Gumuser G."
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Item Effects of 93m93m and 33m33mTc-MDP administration on dual-energy X-ray absorptiometry bone mineral density measurements(2009) Gumuser G.; Parlak Y.; Topal G.; Aras F.; Ruksen E.; Sayit E.Objective Nuclear medicine procedures are often performed in close-time proximity to bone densitometry studies. The purpose of this study was to determine the effects of 99m99mTc-hexakis-2-methoxyisobutyl isonitrile (MIBI) and 99m99mTc-methylene diphosphonate (MDP) on the accuracy of bone mineral density (BMD) measurements performed using dual-energy X-ray density. Methods The effect of a diagnostic dose of 99m 99mTc-MIBI on BMD estimations in the lumbar spine and the left total hip was assessed in 30 patients (19 female, 11 male; mean age: 55.5 ±±10.5 years) by using a Lunar DPX-NT scanner. Thirty patients, admitted to the nuclear medicine department for bone scintigraphy (15 female, 15 male; mean age: 56 ± 15.92 years), were included into the study. Each patient underwent dual-energy X-ray density assessment for which a Lunar DPX-NT scanner was used before and 2 h after intravenous injection of 99m 99mTc-MDP (925MBq) and 99m99mTc-MIBI (1110MBq). BMD measurements were calculated from lumbar spine (including L2-4) and left hip (including femoral neck, trochanter, and total hip). For statistical analysis, the Wilcoxon test was used and a P value of less than 0.05 was accepted as statistically significant. Results According to Wilcoxon's statistical test, we found extremely significant changes on the measured BMD, T-score, before and 2h after the injection of 99m99mTc-MIBI for lumbar spine and left hip in 30 patients. We found statistically significant decrement on measured BMD from lumbar spine and trochanter before and 2 h after the injection of 99m 99mTc-MDP. Although MDP BMD values in femoral neck and total hip were decreased after the injection of Tc-99m, they did not reach a statistically significant value. The comparison of pre-T-score and post-T-score values showed a statistically significant decrease after the injection for only L2-4 lumbar spine (P= 0.002), but left hip of pre-T-score and post-T-score values did not reach a statistically significant value. © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins.Item Comparative effects of risedronate, atorvastatin, estrogen and SERMs on bone mass and strength in ovariectomized rats(2009) Uyar Y.; Baytur Y.; Inceboz U.; Demir B.C.; Gumuser G.; Ozbilgin K.Objective: The aim of this study was to investigate bone protective effects of risedronate, atorvastatin, raloxifene and clomiphene citrate in ovariectomized rats. Methods: Our study was conducted on 63 rats at Experimental Research Center of Celal Bayar University. Six-month-old rats were divided into seven groups. There were five drug administered ovariectomized groups, one ovariectomized control group without drug administration and one non-ovariectomized control group without drug administration. Eight weeks postovariectomy, rats were treated with the bisphosphonate risedronate sodium, the statin atorvastatin, the estrogen 17β-estradiol and the selective estrogen receptor modulators (SERMs) raloxifene hydrochloride and clomiphene citrate by gavage daily for 8 weeks. At the end of the study, rats were killed under anesthesia. For densitometric evaluation, left femurs and tibiae were removed. Left femurs were also used to measure bone volume. Right femurs were used for three-point bending test. Results: Compared to ovariectomized group, femur cortex volume increased significantly in non-ovariectomized group (p = 0.016). Compared to non-ovariectomized group, distal femoral metaphyseal and femur midshaft bone mineral density values were significantly lower in ovariectomized group (p = 0.047). In ovariectomy + atorvastatin group, whole femur and femur midshaft bone mineral density and three-point bending test maximal load values were significantly higher than ovariectomized group (p = 0.049, 0.05, and 0.018). When compared to the ovariectomized group, no significant difference was found with respect to femoral maximum load values in groups treated with risedronate, estrogen, raloxifene and clomiphene (p = 0.602, 0.602, 0.75, and 0.927). In ovariectomy + risedronate group, femur midshaft bone mineral density values were significantly higher than the values in ovariectomized group (p = 0.023). When compared to ovariectomized group, no significant difference was found with respect to femur midshaft bone mineral density values in groups treated with estrogen, raloxifene and clomiphene (p = 0.306, 0.808, and 0.095). Conclusions: While risedronate sodium prevented the decrease in bone mineral density in ovariectomized rats, atorvastatin maintained mechanical characteristics of bone and also prevented the decrease in bone mineral density as risedronate sodium. © 2009 Elsevier Ireland Ltd. All rights reserved.Item Assessment of alveolar epithelial permeability with Tc-99m DTPA aerosol scintigraphy in patients with Sjogren syndrome(2010) Pirildar T.; Gumuser G.; Ruksen E.; Sakar A.; Dinc G.; Sayit E.Sjögren's syndrome (SjS) is a systemic autoimmune disease that mainly affects the exocrine glands and usually presents as persistent dryness of the mouth and eyes. Lung disease in SjS has been reported to occur early following clinical presentation of the disease. In this study, technetium-99m diethylene triamine penta-acetic acid (Tc-99m DTPA) aerosol inhalation scintigraphy was used to assess the pulmonary membrane permeability in patients with primary SjS. A total of 18 patients with primary SjS and 13 healthy controls were investigated. Clinical evaluation, chest X-ray examination, pulmonary function tests, Tc-99m DTPA aerosol scintigraphy were performed in all the cases. The presence of respiratory symptoms (dyspnea and cough), duration of sicca symptoms were recorded. The clearance half time of Tc-99m DTPA radioaerosols in patients with SjS (20.49 ± 2.56 min) was faster when compared to normal controls (42.32 ± 13.28 min) (P = 0.000) which means that there is a significant increase in lung permeability in patients with SjS compared to the controls. There is also a significant difference between PI of patients with SjS (0.34 ± 0.09) and that of controls (0.42 ± 0.07) (P = 0.012). According to the results of our preliminary study, one can detect pulmonary involvement by Tc-99m DTPA aerosol inhalation scinti-graphy in patients with primary SjS. © Springer-Verlag 2009.Item Technetium-99m-hexamethylpropylene amine oxime lung scintigraphy findings in patients with Behcs disease(2011) Gumuser G.; Pirildar T.; Tarhan S.; Batok D.; Ruksen E.; Sakar A.; Sayit E.AIM: Behçet's disease (BD) is a multisystem disorder that is characterized by vasculitis, and consists of a triad of recurrent ulcers of the oral and genital mucosa with relapsing uveitis. The prevalence of pulmonary involvement varies in the range of 1-10% in various studies, and its complications are severe and life threatening. To objectively assess the degree of pulmonary vascular endothelial damage in BD, the lung uptake, and the clearance rate of technetium-99m-hexamethylpropylene amine oxime (Tc-99m-HMPAO) were determined. METHODS: Twenty-three nonsmoking patients with BD (10 female, 13 male) and 11 (six female, five male) healthy nonsmoking controls underwent Tc-99m-HMPAO lung scanning, pulmonary function tests (PFT), chest radiograph examination, contrast-enhanced spiral chest computed tomography scanning, and high-resolution computed tomography examinations. Immediately after the bolus injection of 740 MBq of Tc-99m-HMPAO posterior sequential images were obtained at 1-s intervals for 150 s and subsequent images were obtained at one frame per minute (min) over a 10-min period, using a double-headed gamma camera equipped with a low-energy all-purpose parallel hole collimator. Dynamic images were used to calculate the Tc-99m-HMPAO lung clearance rate (T1/2). Simultaneously, a static anterior image, including a large part of the liver, was obtained of 5-min duration at 10 min after the injection. Regular regions of interests were drawn over the midportion of the right lung and the highest activity area of the liver parenchyma was selected and lung/liver (L/Li) uptake ratios were calculated to represent the degree of pulmonary vascular endothelial damage. RESULTS: Chest radiograph, high-resolution computed tomography, and computed tomography findings in patients with BD were nonspecific for BD. There was also a statistically significant difference between patients with BD (30.26±10.55 s) and normal controls (19.53±6.24 s) on their T1/2 values (P=0.0004). The results show that the L/Li ratios on the Tc-99m-HMPAO lung scan were significantly higher in patients with BD (0.60±0.19) than those in normal controls (0.39±0.07) (P=0.0021). Using a cutoff value of 0.50, 15 of 23 (65%) patients with BD had increased L/Li ratios. No correlation was found between the mean T1/2 values of Tc-99m-HMPAO clearance and the PFT in patients with BD. The L/Li ratios were not correlated with PFT in patients with BD. CONCLUSION: The degree of pulmonary vascular endothelial damage was represented as increased L/Li ratios and decreased lung clearance rate measured on the Tc-99m-HMPAO lung scan in patients with BD. Our results indicated that determining the T1/2 values and the L/Li ratios on Tc-99m-HMPAO lung imaging should be an objective method to assess subclinical pulmonary damage even in the early stages of BD in the patients. © 2011 Wolters Kluwer Health | Lippincott Williams &Wilkins.Item Assessment of toll-like receptor-4 gene polymorphism on pyelonephritis and renal scar(2012) Akil I.; Ozkinay F.; Onay H.; Canda E.; Gumuser G.; Kavukcu S.The aim of this study was to evaluate the effect of the TLR-4 gene TLR4 c.896AItem Assessment of lung toxicity caused by bleomycin and amiodarone by Tc-99m HMPAO lung scintigraphy in rats(2013) Gumuser G.; Vural K.; Varol T.; Parlak Y.; Tuglu I.; Topal G.; Sayit E.Aim: The purpose of the study was to determine the lung toxicity caused by amiodarone (AD) and bleomycin (BLM) in rats, by means of Tc-99m HMPAO lung scintigraphy. Methods: Thirty albino rats were randomly divided into five groups. After AD or BLM was dissolved with isotonic saline (SF), a 0.5 ml solution was applied to the right bronchus via a catheter. Group 1 (n = 5 rats) received a single dose of AD, group 2 (n = 5) received two doses of AD, group 3 (n = 9) received BLM, group 4 (n = 3) received hydrochloric acid (HCl), and group 5 (n = 8) received SF. Rats in groups 1, 2, 3 and 5 were given 37 MBq Tc-99m HMPAO from the tail vein on days 7, 14, 21 and 28, and at 4 and 24 h in group 4. Static images of 10 min duration were obtained at 30 and 60 min by a double-headed gamma camera (Infinia, GE, Tirat Hacermel, Israel) on 256 × 256 matrix. Regular regions of interests were drawn over the right lung (RL), left lung (LL) and the liver (Li), and lung/liver (L/Li) ratios were calculated. After the scintigraphic imaging procedures were completed, rats were killed. Lung tissues were evaluated on a scale of (+) to (+++++) for edema, alveolar structural integrity and infiltration by inflammatory cells. Results: Groups 2 and 3 showed statistically significant differences in RL/Li and LL/Li ratios, whereby RL/Li was higher than LL/Li (p < 0.05). There were no significant differences in RL/Li and LL/Li ratios in group 5 (p > 0.05). In histopathological examination, minimal damage or artifacts were observed in group 5. In group 4, almost all pathological findings were present in the right lung. Statistically significant (p < 0.01) histological differences were found when groups 1 and 5 were compared. More significant (p < 0.001) pathological effects were noted when groups 2 and 3 were compared to both groups 5 and 1. Injury was more prominent in the lung tissues of the control rats that were given HCl. Increased RL/Li ratios and histopathological findings were consistent. Conclusion: Tc-99m HMPAO lung scan are found to be useful in the identification of patients with lung toxicity. The simplicity of the procedure and lower radiation exposure are the advantages of Tc-99m HMPAO lung scan. © 2013 The Author(s).Item Samarium-153 therapy for prostate cancer: The evaluation of urine activity, staff exposure and dose rate from patients(Oxford University Press, 2015) Parlak Y.; Gumuser G.; Sayit E.The aim of this study was to determine the excretion of Samarium-153-ethylenediaminetetramethylphosphonic acid (153Sm- EDTMP) in urine and to calculate the dose rate of its retention in the body as a function of time and the dose received by the skin of laboratory staff 's finger. Urine samples were collected from 11 patients after intravenous injection of 153Sm-EDTMP. The measurements of dose rate were performed. Thermoluminescent dosemeters were used for absorbed dose measurements. Effective half-lives that were calculated from urine sample measurements were found as 7.1±3 h within the first 24 h. Whole body dose rates before collecting urine of patients were 60.0 ± 15.7 μSv h21 for within 1 h following 153Sm-EDTMP administration. The highest finger radiation dose is to the right-hand thumb (3.8 ± 2 mGy). The results of the study imply that patients who recieved 153Sm-EDTMP therapy should be kept a minumum of 8 h in an isolated room at hospital and that one staff should give therapy at most two patients per week. © The Author 2014.Item Bone marrow radiation dosimetry of high dose 131I treatment in differentiated thyroid carcinoma patients(Novin Medical Radiation Institute, 2016) Parlak Y.; Demir M.; Cavdar I.; Ereees S.; Gumuser G.; Uysal B.; Kaya G.C.; Koç M.; Sayit E.Background: Radiation absorbed dose to the red bone marrow, a critical organ in the therapy of thyroid carcinoma, is generally kept below 2 Gy for non-myeloablative therapies. The aim of this study was to calculate bone marrow radiation dose by using MIRDOSE3 package program and to optimize the safe limit of acivity to be administered to the thyroid cancer paients. Materials and Methods: In this study, 83 thyroid cancer patients were divided into 3 groups based on the amount of acivity administered into the body. In the groups, 3700 MBq, 5550 MBq and 7400 MBq activities were used respecively. The curves of ime-acivity were drawn from blood samples counts and effective half-life and residence time were calculated. Correlations of bone marrow radiation dose and radioiodine effective half-life were determined as a function of administered activity via ANOVA test. Tg levels and tumour diameters were compared using Spearman's correlation. Results: The effective half-lives of 131I for three groups of whole-body, receiving 3700 MBq, 5550 MBq and 7400 MBq were calculated as 20.57±5.4, 17.8±5.8 and 18.7±3.9 hours, respectively. The average bone marrow doses for 3 groups of patients were 0.32±0.08 Gy, 0.42±0.14 Gy and 0.60±0.24 Gy, respectively. Conclusion: It was concluded that, the bone marrow dose to the patients still remains within the recommended level even after administering an activity of 7400 MBq of 131I to the patients.Item Evaluation of abnormal radiological findings in children aged 2 to 36 months followed by recurrent urinary tract infection: A retrospective study(Taylor and Francis Ltd, 2017) Ozen C.; Ertan P.; Aras F.; Gumuser G.; Ozkol M.; Dinc G.H.Our aim is to determine the rational usage of imaging techniques in order to prevent or minimize permanent renal damage in recurrent urinary tract infections (UTIs). This study was enrolled children aged between 2 and 36 months, following-up with the diagnosis of recurrent UTI. All children had ultrasonography (USG) and dimercaptosuccinic acid scanning, 39 of them had underwent on voiding cystourethrography. There were 133 children (87 girls, 46 boys) with the mean age of 32.82±38.10 months included into the study. Forty-three kidney units were normal in ultrasonogram of which seven units had reflux whereas among 35 units with hydronephrosis 22 units had reflux. Sensitivity and specificity presence of hydronephrosis in ultrasonogram for prediction of reflux was 75.9% and 73.5%, respectively. There were 19 dilated ureters in ultrasonogram, and among them 14 had reflux. Sensitivity and specificity of presence with ureteral dilatation in ultrasonogram for prediction of reflux was found as 48.3% and 89.8%, respectively. The sensitivity of parenchymal thinning seen in ultrasonogram for the evaluation of renal parenchyma was 15.9%, whereas specificity was 98.2%.Sensitivity and specificity of dimercaptosuccinic acid for prediction of reflux was 51.6% and 72.3%, respectively. The normal ultrasonogram findings cannot rule out neither possibility of reflux presence nor development of renal scarring. Therefore, DMSA scanning has major role both in determination of parenchymal damage and prevention of scarring. Also we get an important result as ureteral dilatation seen in USG, related to presence of reflux. © 2016 The Author(s).Item Multifunctional molecular imaging probes for estrogen receptors: 99mTc labeled diethylstilbestrol (DES) conjugated, cuinp quantum dot nanoparticles (DESCIP)(Springer Netherlands, 2017) Moharrami P.; Unak P.; Guldu O.K.; Medine E.I.; Gumuser G.; Bilgin E.S.; Aras O.A theranostic nanoparticle was synthesized based on diethylstilbestrol conjugated with phosphate, copper, and indium (DESCIP) and labelled with 99mTc which can be used for SPECT imaging of ER-enriched cancers. In vitro biological activity of 99mTc-DESCIP was examined in breast adenocarcinoma cells (MCF-7), prostatic carcinoma cells (PC-3), and pulmonary epithelial cells (A-549). In vivo lymph node imaging was performed in normal and receptor blocked female New Zealand rabbits. Results demonstrated that 99mTc-DESCIP and DESCIP has potential for imaging ER-enriched tumors such as breast and prostate tumors, and their metastases in the lung, as well as improving management for their therapies. © 2017, Akadémiai Kiadó, Budapest, Hungary.Item EFFECTIVE HALF-LIFE, EXCRETION AND RADIATION EXPOSURE OF 177LU-PSMA(Oxford University Press, 2023) Parlak Y.; Mutevellzade G.; Sezgln C.; Goksoy D.; Gumuser G.; Saylt E.The study aims to evaluate the radiation safety conditions by detecting the patient's urine excretion rate, calculating the effective half-life, and determining the retention of 177Lu-PSMA in the body. Urine samples of patients were collected for 24 hours (6, 12, 18, and 24 hours) following the infusion, excretion rate and retention of 177Lu-PSMA in the body of patients were calculated. The measurements of dose rate were performed. Effective half-life calculated from dose rate measurements was found as 18.5 ± 11 h within the first 24 h and 48.1 ± 22.8 h between 24 and 72 h. Excreted activity in urine was found as 33.8 ± 20.7, 40.4 ± 20.3, 46.1 ± 22.4, and 53.3 ± 21.5% of total doses at 6, 12, 18, and 24 h after administration, respectively. External dose rates for 4 h and 24 h were 24.51 μSv/h, 16.14 μSv/h, respectively. Our results showed that 177Lu-PSMA treatment was suitable for outpatient treatment in terms of radiation safety. © 2023 The Author(s).Item Inguinoscrotal Bladder Hernia Mimicking Testicle Tumor(SAGE Publications Ltd, 2023) Sezgin C.; Duzgun F.; Mutevelizade G.; Gumuser G.; Sayit E.Bladder hernias usually begin asymptomatically and are discovered incidentally at the time of discovery. Preoperative diagnosis of bladder hernias is important to reduce the risk of bladder injury during surgery. Although F-18 FDG PET/CT is applied for oncological purposes, benign conditions should also be taken into account when evaluating the implants. In this article, a case of bladder hernia, which can be confused with pathological cancer involvement, with the diagnosis of F-18 FDG PET/CT performed in a 73-year-old male patient with renal cell carcinoma is presented. © The Author(s) 2023.Item Predicting thyroid cancer ablation success: Pre-ablative 99mTc-Pertechnetate and post-ablative 131I scan comparison; [Prédiction du succès de l'ablation dans le cancer de la thyroïde : une comparaison de la scintigraphie pré-ablative à la 99mTc-pertechnétate et de la scintigraphie post-ablative au 131I](Elsevier Masson s.r.l., 2024) Mutevelizade G.; Parlak Y.; Bozdemir B.C.; Sezgin C.; Gumuser G.; Sayit E.Introduction: The purpose of this study was to evaluate the relationship between pre-ablative 99mTc-pertechnetate scintigraphy, and therapeutic iodine-131 (131I) whole-body scan (TxWBS), with ablation status and to investigate the possible predictive factors for successful ablation in differentiated thyroid carcinoma (DTC) patients. Materials and methods: A total of 330 DTC patients underwent 99mTc-pertechnetate scintigraphy after thyroidectomy. Uptake values were determined using the region-of-interest technique. All patients had neck ultrasonography and TxWBS. Both scintigraphic scans were interpreted visually and qualitatively. The ablation status was evaluated with a diagnostic 131I whole-body scan. Results: The success rate for residual thyroid ablation was 88.8%. The sensitivity, specificity, accuracy, PPV, and NPV of 99mTc-Pertechnetate scintigraphy were 82.4%, 87.5%, 82.7%, 99.2%, and 20.2%, respectively. Pre-ablative TG values and 99mTc uptake (%) were significantly lower in successfully ablated patients. The 99mTc uptake was determined as a significant predictive factor for ablation success (P = 0.000). The optimal 99mTc uptake cut-off value of 0.75% was demonstrated for successful ablation. There were significant positive correlations between the visual and the calculated uptake (%) of residual tissues on both scintigraphic scans, Considering the number of remnant tissue foci, significant positive correlations were found between 99mTc-Pertechnetate scintigraphy, TxWBS, and USG. Conclusion: Pre-ablative 99mTc-Pertechnetate uptake (%) value of the remnant tissue can predict the ablation status in DTC patients. 99mTc-Pertechnetate scintigraphy, which is an easily applicable and accessible imaging method, has maintained its place in the postoperative and pre-ablative period in DTC patients over the years and has not lost any of its value. © 2024 Elsevier Masson SASItem Splenosis imaging with 99mTc nano-colloid as a different mimicker in a lymphoma patient on 18F- FDG PET/CT; [Scintigraphie aux nanocolloïdes-33mTc pour différencier une splénose d'un ganglion lymphatique fixant le 18F-FDG](Elsevier Masson s.r.l., 2024) Sezgin C.; Parlak Y.; Mutevelizade G.; Gumuser G.; Sayit E.Fluorodeoxyglucose (FDG) 18F-FDG PET/CT plays an important role in lymphoma staging and evaluation of treatment response. Mimics should be considered when evaluating 18F-FDG PET/CT images to perform correct staging and correct treatment response evaluation. Splenosis is one of the causes that may cause misinterpretation by mixing with lymph nodes in lymphoma patients. In our case report, we visualized splenosis mimicking lymph node in a 50-year-old lymphoma patient with 99mTc nano-colloid scintigraphy. © 2024 Elsevier Masson SAS