Browsing by Author "Sayit, E"

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    Gastric emptying of solids and its relationship with microalbuminuria in children and adolescents with type 1 diabetes mellitus
    Ersoy, B; Sayit, E; Can, S; Urk, V; Batok, D; Polat, M
    Background: The aims of the present study were to determine the frequency of delayed gastric emptying in children and adolescents with type 1 diabetes mellitus (T1DM) and to investigate the relationship between gastric emptying rate and other contributing factors (e. g. serum HbA1c, duration of diabetes and microalbuminuria) in these patients. Methods: This was a clinical trial evaluating the rate of gastric emptying of solid meals in 33 children and adolescents with T1DM and in 26 healthy peers using a radionuclide method. Three consecutive overnight urine collections were used to calculate the albumin excretion rate. Results: There was no significant difference in the gastric half-emptying time (GE t 1/2) between patients and controls (151.7 +/- 154.5 vs 109.8 +/- 60.5 min, respectively; P = 0.885) or the frequency of delayed gastric emptying (36.4% vs 30.8%, respectively; P = 0.433). There was a moderately positive correlation between GE t1/2 and the duration of diabetes (r = 0.380; P = 0.029). There was no correlation between GE t1/2 and microalbumin levels in T1DM patients. In these patients, the body mass index standard deviation scores were significantly lower than in patients with normal gastric emptying (-0.13 +/- 0.87 vs 0.7 +/- 1.23, respectively; P = 0.044). Conclusion: Progression of delayed gastric emptying is more likely to be related to a longer duration of diabetes than glycemic control in children and adolescents with T1DM. Patients with delayed gastric emptying are thinner compared with patients with a normal rate of gastric emptying; they may also be asymptomatic.
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    A Comprehensive Analysis of Volumetric 68 Ga-PSMA PET/CT Parameters, Clinical and Histopathologic Features: Evaluation of the Predictive Role
    Mutevelizade, G; Parlak, Y; Arikbasi, CS; Guemüser, G; Sayit, E
    Objectives: To evaluate the relationships between volumetric 68 Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/ computed tomography (PET/CT) parameters, Gleason score (GS), prostate-specific antigen (PSA) levels, histopathological data, and metastatic status in newly diagnosed prostate cancer (PCa) patients and to assess the predictive factors for progression despite treatment. Methods: A total of 78 newly diagnosed patients with PCa who had 68 Ga-PSMA PET/CT scans were included. Clinical parameters, histopathological data, and metastatic status were documented, and volumetric parameters of primary prostate lesions were measured. All obtained data were compared statistically. Results: Primary prostate tumor maximum standardized uptake value (SUV max ) and GS were significantly related to serum PSA levels (p<0.05). PSA levels and SUV max values were significantly higher in patients with lymph node metastases than in those without. GS was found to be significantly increased in metastatic patients. PSMA-derived tumor volume (PSMA-TV) and total lesion PSMA of the primary lesion had a significant relationship with PSA value, GS, and regional lymph node metastases. Receiver operating characteristic analysis, conducted in patients with metastatic and localized disease, identified the cutoff value for SUV max as 10.85. According to the results of the logistic regression analysis, PSMA-TV was found to be a predictive factor for progression despite treatment. Conclusion: 68 Ga-PSMA PET/CT remains an invaluable imaging modality that should be considered first in PCa staging because of its superior compatibility with clinical and histopathologic data. The importance of this method goes beyond diagnostic accuracy; it also extends into the predictive domain, where the PSMA-TV value of primary prostate lesions is a potential predictor of treatment efficacy. This information is valuable for personalizing patient treatment, improving prognostic accuracy, and predicting clinical outcomes.
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    Splenosis imaging with 99mTc nano-colloid as a different mimicker in a lymphoma patient on 18F-FDG PET/CT
    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.
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    Assessment of alveolar epithelial permeability in Behcet's disease with 99mTc-DTPA aerosol scintigraphy
    Gumuser, FG; Pirildar, T; Batok, D; Sakar, A; Ruksen, E; Sayit, E
    Objective Behcet's disease (BD) is a multisystem disorder characterized by vasculitis, and consists of a triad of recurrent ulcers of the oral and genital mucosa with relapsing uveitis. The prevalance of pulmonary involvement varies in the range of 1-10% in various studies and its complications are severe and life threatening. In this study, we investigated the changes of pulmonary epithelial permeability of patients with BD using technetium-99m diethylene triamine penta-acetic acid (Tc-99m-DTPA) aerosol scintigraphy, so as to begin the therapy regimen as soon as possible. Methods Twenty-one nonsmoking patients with BD (8 women, 13 men; mean age 38.67 +/- 8.86 years) and 15 healthy volunteer nonsmoking controls (8 women, 7 men; mean age 50.87 +/- 12.45 years) underwent Tc-99m-DTPA aerosol inhalation scintigraphy and pulmonary function tests (PFTs). Subjects inhaled 1480 MBq of Tc-99m-DTPA for 4 min in the supine position. Scintigraphic data were recorded dynamically (1 frame/min) in the posterior projection on a 64 x 64 matrix for a 30-min period using a double-headed gamma camera (Infinia, GE, Tirat Hacarmel, Israel) equipped with a low-energy all-purpose parallel hole collimator. Half time of Tc-99m-DTPA clearance (T (1/2)) was calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was also calculated by dividing the peripheral total counts by the sum of the peripheral and central total counts on the first minute image, in order to quantify the distribution of the inhaled aerosol. Results The clearance half time of Tc-99m-DTPA radioaerosols in the BD patients (24.81 +/- 6.22 min) was faster than in the normal control group (46.53 +/- 22.41 min) (P = 0.004). There was also a significant difference between PI of the patients with BD (0.15 +/- 0.03) and that of the controls (0.21 +/- 0.06) (P = 0.002). No correlation was found between the mean T (1/2) values of Tc-99m-DTPA clearance or the spirometric measurements in the BD patients. Penetration indices were not correlated with PFT in the BD patients. Conclusions Lung epithelial permeability of the patients with BD was significantly higher than that of the normal subjects. The results of this study demonstrated that the assessment of lung epithelial permeability using Tc-99m-DTPA aerosol scintigraphy could predict the presence of lung involvement in the early stages of BD.
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    Technetium-99m-hexamethylpropylene amine oxime lung scintigraphy findings in patients with Behcet's disease
    Gumuser, G; Pirildar, T; Tarhan, S; Batok, D; Ruksen, E; Sakar, A; Sayit, E
    Aim Behcet'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 oxirne (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 150s 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 (T(1/2)). Simultaneously, a static anterior image, including a large pad 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 +/- 10.55s) and normal controls (19.53 +/- 6.24s) on their T(1/2) 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 T(1/2) 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 T(1/2) 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. Nucl Med Commun 32:363-368 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.
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    The Imaging Performance of 89Zr in TOF PET/CT system
    Parlak, Y; Goksoy, D; Sezgin, C; Medine, I; Gumuser, G; Aras, O; Sayit, E
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    The evaluation of urine activity and external dose rate from patients receiving radioiodine therapy for thyroid cancer
    Demir, M; Parlak, Y; Çavdar, I; Yeyin, N; Tanyildizi, H; Gümüser, G; Sayit, E; Erees, S; Sayman, H
    The aim of this study was to determine the external dose rate of iodine retention as a function of time in the bodies of thyroid cancer patients during their isolation period in the hospital. Urine samples were collected at 6th, 12th, 18th, 24th h and 2nd, 3rd, 4th, 5th d from 83 patients after oral administration of I-131 and counted. The external dose rates were also simultaneously determined at the same time points. Then, it was expressed as retained radioiodine body activity versus dose rate. Effective half life calculated from urine sample measurements was found as 18.41.8 h within the first 24 h and 642.7 h between 48 and 120 h. According to this results, the external dose rate (20 Sv h(1)), which patients could be discharged, was achieved after 48 h for 3700 and 5550 MBq, and after 72 h for 7400 MBq of I-131 treatments.
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    The role of Tc-99m RBC scintigraphy in the differential diagnosis of orbital cavernous hemangioma
    Sayit, E; Durak, I; Capakaya, G; Yilmaz, M; Durak, H
    The cavernous hemangioma is the most common benign orbital tumor in adults. Its presentation is during the forth to fifth decades with a slowly progressive unilateral proptosis. Intraconal cavernous hemangiomas may be difficult to differentiate from other intraconal lesions such as schwannomas, meningiomas and hemangiopericytomas. We report a case of orbital cavernous hemangioma diagnosed by Tc-99m RBC scintigraphy. Tc-99m RBC scintigraphy revealed a typical scintigraphic pattern in which there is intense focally increased uptake on the delayed image. We conclude that Tc-99m RBC scintigraphy can be a useful method in the differential diagnosis of orbital cavernous hemangioma as in hepatic hemangioma.
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    Landau-Kleffner syndrome
    Sayit, E; Dirik, E; Durak, H; Uzuner, N; Anal, Ö; Çevik, NT
    Landau-Kleffner syndrome (LKS) is a rare childhood disorder characterized by acquired aphasia with seizures and electroencephalogram (EEG) abnormalities. Tc-99m-HMPAO SPECT was performed in three right handed children with LKS. A relative decrease in perfusion was found in the left temporal cortex of all three patients and also in the left frontoparietal cortex of one patient with hyperkinetic behavior. Degree of regional cerebral perfusion impairment did not correlate with the severity of clinical and EEG abnormalities. Asymmetrical temporoparietal perfusion appears characteristic of LKS. SPECT findings in LKS were evaluated as useful in elucidating the pathogenic features of the disorder in the brain.
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    Comparison of brain perfusion SPECT and MRI findings in children with neuronal ceroid-lipofuscinosis and in their families
    Sayit, E; Yorulmaz, I; Bekis, R; Kaya, G; Gumuser, FG; Dirik, E; Durak, H
    Neuronal ceroid-lipofuscinoses (NCL) are among the progressive encephalopathies of childhood that are inherited in an autosomal recessive manner. In this study we specifically aimed to investigate any white-matter changes in the carriers (parents) and the healthy siblings of individuals with neuronal ceroid lipofuscinosis disease and whether we may be able to predict the occurrence of any neurological symptoms in healthy children in the future thus enabling early management. Materials and Methods: Since the NCLs are genetically determined diseases, we investigated fifteen individuals in three families that had diseased children of the juvenile type, with brain perfusion SPECT and MRI. Brain per-fusion SPECT was performed after administering 222555 MBq (6-15 mCi) Tc-99m HMPAO intravenously in a dimmed and quiet room. Imaging was performed at least one hour after injection, with a three headed gamma camera equipped with high resolution collimators. A Metz filter (FWHM: 11 mm) was used for processing. Cranial MRI was performed with an imager operating at 1.5 Tesla. Spin-echo T1- and T2-weighted and FLAIR slices were obtained for each individual. Results: In all of the five diseased children we observed pathologic findings both on MRI and Tc-99m HMPAO SPECT. The findings on MRI were mainly features of cerebral and cerebellar atrophy and the observations on Tc-99m HMPAO SPECT were regional perfusion abnormalities. We observed some structural abnormalities on MRI in four of the parents and two of the four healthy siblings. We also noted perfusion abnormalities on Tc-99m HMPAO SPECT in two of the parents and two of the healthy siblings. Conclusion: Because the disease is inherited in an autosomal recessive manner, the parents and the healthy siblings were not supposed to exhibit any demonstrable brain lesions, but the brain perfusion SPECT and MRI examinations clearly revealed multiple lesions in some of the parents and healthy siblings. Detailed neurological examinations of these individuals were normal except for one apparently healthy sibling (EY). Follow-up imaging of these families is being undertaken and further studies are essential in understanding the pathogenesis and genetics of neuronal ceroid-lipofuscinoses.
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    Pulmonary Epithelial Permeability and Radioaerosol Penetration in Pulmonary Tuberculosis
    Sayit, E; Erer, OF; Bekis, R; Tasci, C; Konya, A; Gümüser, G; Kaya, GÇ; Özkan, SA; Durak, H
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    Clinical significance of lung perfusion defects in children with post-infectious bronchiolitis obliterans
    Yüksel, H; Yilmaz, Ö; Ürk, V; Yüksel, D; Göktan, C; Savas, R; Sayit, E
    Clinical significance of segmental lung perfusion defects in children with bronchiolitis obliterans (BO), have not been reported before. The aim of this study was to evaluate clinical significance of lung perfusion defects in children with BO and to reveal its impact on follow up. The study included 38 children aged 9 to 60 months (17.8 +/- 13.4 months) with BO. Diagnosis was based on persistent respiratory findings beyond six weeks and oligemic-mosaic pattern in lung high resolution computerized tomography. Chest X-ray, 24 hour esophageal pH monitoring, sweat chloride test, immunoglobulin levels and respiratory viral screening were carried out in all. Lung perfusion scintigraphy was carried out at least three months after the first clinical sign of BO. Perfusion defects were scored. Scintigraphy demonstrated perfusion defects in 24 (63.2%) patients but was normal in 14 (36.8%). Number of segments having perfusion defects was 2.9 +/- 2.6. Mean number of exacerbations and days of hospitalization during the first year of follow up were 4.7 +/- 4.4 and 26.9 +/- 29.8 respectively. It was detected that number of perfusion defects correlated significantly with the number of exacerbations and duration of hospitalization (r= 0.66 and p= 0.00). In conclusion, number and extent of segments with perfusion defects in lungs of children with BO are correlated with clinical severity. Therefore, evaluation of lung perfusion status may aid in clinical determination of disease severity and its follow-up.
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    Unexpected Metastatic Localizations of Prostate Cancer Determined by 68Ga PSMA PET/CT: Series of Four Cases
    Mütevelizade, G; Sezgin, C; Gümüser, G; Sayit, E
    Prostate-specific membrane antigen (PSMA) is a transmembrane protein with overexpression in most prostate cancer cells. Gallium-68-(Ga-68) PSMA positron emission tomography/computed tomography (PET/CT) imaging is a game-changer in the management of prostate cancer. 68Ga PSMA PET/CT scan is advanced and a promising radioligand has high sensitivity in determining lesions of prostate cancer with a high tumor to background ratio. The most common areas of metastasis are the bone and pelvic lymph nodes. The prognosis of prostate cancer is mainly determined by the status of metastases. The presence and the localization of metastases affects treatment planning. In our cases, we presented some examples of uncommon sites of metastases such as the brain, adrenal glands, penis and orbit. Improvements in imaging techniques, such as Ga-68 PSMA PET/CT have led to the possibility to make more determination of rare metastase sites in prostate cancer patients.
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    Baseline SUV Range for Liver and Blood Pool in Patients Undergoing F-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography
    Parlak, Y; Göksoy, D; Mütevelizade, G; Gümüser, G; Sayit, E
    Introduction: The aim of the study was to define the baseline SUVmax range in the liver and blood pool of patients undergoing fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) imaging. Methods: Five hundred and thirty-one patients (264 females, 267 males; mean age: 59.6 dagger 13.4 years) who were admitted to our department for PET/CT imaging before treatment were included in the study. Patient preparation, acquisition parameters and reconstruction protocols were standardized for all patients prior to PET/CT imaging. The mean serum glucose levels and mean age of the patients were calculated. These patients were divided into 10 groups as esophagus, stomach, colon, rectum, larynx, lung, breast, endometrium, ovarian cancers and lymphoma. 2D region of interests were plotted to calculate the mean SUV values in the right lobe of the liver and the aortic arch for the blood pool. Results: Normal Gaussian distributions of mean SUV changes for liver and blood pool were obtained. Mean SUVmax and SUVmean values for liver were 2.73 +/- 0.22 and 2.34 +/- 0.16, respectively, and 1.80 +/- 0.2 and 1.57 +/- 0.14 for blood pool, respectively. Conclusion: It was concluded that the obtained SUV ranges may provide ease of application in the clinic in evaluating qualitative tumor response and comparing tumor/background ratios in cancer patients.
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    Body Mass Index Assessment In PET/CT Imaging Patients
    Mutevelizade, G; Parlak, Y; Sezgin, C; Sayit, E; Gumuser, G
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    Technetium-99m Hexamethylpropylene Amine Oxime Lung Clearance Rate in Patients with Behcet's Disease
    Gumuser, G; Pirildar, T; Tarhan, S; Kararmaz, M; Sakar, A; Sayit, E
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    Primary pleural synovial sarcoma with diffuse pleural involvement: A case report
    Mutevelizade, G; Sayit, E
    Synovial sarcoma (SS) is a mesenchymal tumor which generally affects the soft tissues of the extremities. Primary pleural synovial sarcoma (PPSS) is a very rare and aggressive subtype of SS. A 73-year-old male patient presented with chest-back pain and dyspnea. Hypermetabolic diffuse pleural lesions were detected in 18F-FDG PET/CT performed after pleural nodular thickenings were observed on CT. As the result of the molecular analysis performed in the excisional biopsy, SYT-SSX mutation was detected and the patient was diagnosed as SS. Pazopanib treatment was commenced. We are reporting a very rare case of PPSS with diffuse pleural involvement. @ 2023 Elsevier Masson SAS. All rights reserved.
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    Assessment of lung toxicity caused by bleomycin and amiodarone by Tc-99m HMPAO lung scintigraphy in rats
    Gumuser, G; Vural, K; Varol, T; Parlak, Y; Tuglu, I; Topal, G; Sayit, E
    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. 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 x 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. 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. 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.