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    Assessment of chemotherapy-induced changes in bone sarcomas: Clinical experience with Tc-99(m)-MDP three-phase dynamic bone scintigraphy
    (Lippincott Williams & Wilkins, 1999) Ozcan, Z; Burak, Z; Kumanlioglu, K; Sabah, D; Basdemir, G; Bilkay, B; Cetingul, N; Ozkilic, H
    The aim of this study was to evaluate the value of three-phase dynamic bone scintigraphy (TPBS) in the assessment of the response of bone sarcomas to pre-operative chemotherapy and to correlate serial scintigraphic changes with histological findings. The study group comprised 27 patients (osteogenic sarcoma, n = 20; Ewing's sarcoma, n = 5; malignant fibrous histiocytoma, (n = 2) with a mean age of 19.2 years. All patients received (99T)c(m)-methylene diphosphonate TPBS before and after pre-operative chem otherapy. Each phase of the imaging procedure was interpreted qualitatively and quantitatively. The percentage of tumour necrosis was analysed on resection materials following surgery. Histologically, 12 patients were non-responsive (tumour necrosis less than 90%) and 15 patients were responsive (tumour necrosis more than 90%). A decrease in the tumour blood flow ratio and extension were the most notable findings in the responders. The moan change in the tumour blood flow ratio following therapy was 58.7 +/- 8.3% and 19.9 +/- 26.6% (P < 0.005) in responders and non-responders respectively. The accuracy of three-phase imaging and static bone scintigraphy was 88% and 74% respectively Since bone scintigraphy is a valuable technique owing to its ability to detect distant metastases in clinically early disease, TPBS should be helpful in monitoring therapy effects without any additional cost or radiation dose. ((C) 1999 Lippincott Williams & Wilkins).
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    Correlation of Tc-99m-sestamibi uptake with blood-pool and osseous phase Tc-99m-MDP uptake in malignant bone and soft tissue tumors
    (Springer Verlag, 1999) Ozcan, Z; Burak, Z; Erinc, R; Dirlik, A; Basdemir, G; Sabah, D; Ozkilic, H
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    Correlation of Tc-99m-sestamibi uptake with blood-pool and osseous phase Tc-99m-MDP uptake in malignant bone and soft-tissue tumours
    (Lippincott Williams & Wilkins, 2001) Ozcan, Z; Burak, Z; Erinc, R; Dirlik, A; Basdemir, G; Sabah, D; Ozkilic, H
    Technetium-99m-sestamibi (Tc-99m-MIBI) imaging is a well-established modality in oncologic investigations. The current study aimed to investigate whether any relationship could be found between Tc-99m-MIBI uptake and local perfusion in malignant bone and soft-tissue tumours. It also aimed to compare Tc-99m-MIBI images with those of technetium-99m-methylene diphosphonate (Tc-99m-MDP) bone scintigraphy with regard to the activity distribution pattern, intensity and lesion extension. The study group included 24 patients with various bone and soft-tissue tumours. Three-phase bone scintigraphy and Tc-99m-MIBI studies were performed within the same week before any surgical and therapeutic intervention. Images were evaluated visually and quantitatively using regions of interest (ROIs) over the lesion and adjacent normal tissue. The Tc-99m-MIBI study was positive with varying degrees of uptake (range, 1.4-5.3). The mean Tc-99m-MIBI uptake and Tc-99m-MDP blood-pool and osseous phase activity ratios were 2.5 +/- 0.5, 2.8 +/- 1.0 and 5.5 +/- 4.0, respectively. The correlation between the Tc-99m-MIBI uptake and blood-pool ratios was 0.70 (P<0.05). While activity distribution patterns were in agreement in Tc-99m-MIBI and blood-pool images in the majority of cases, Tc-99m-MIBI better delineated tumour viability and extension in five cases. In conclusion, Tc-99m-MIBI accumulation shows a reasonable correlation with blood-pool uptake assuming the presence of multifactorial mechanisms in addition to local hyperaemia. Better delineation of tumour outlines and cellular activity seems to be an advantage of Tc-99m-MIBI scintigraphy which may be helpful in the evaluation of musculoskeletal tumours. ((C) 2001 Lippincott Williams & Wilkins).
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    A correlative study between Tc-99m-ESTCPTA and Tc-99m-MIBI in rats
    (Pergamon-Elsevier Science Ltd, 2002) Unak, P; Enginar, H; Biber, FZ; Lambrecht, FY; Aslani, MAA; Ozkilic, H
    Tissue distribution of the Tc-99m labeled derivative of the estrogen compound 3,17-alpha-estradiolyl propyl 1,4,8,11-tetraazacyclotetradecanyl- 1-(4-methylbenzoic acid) ester (ESTCPTA), which has an 3,17-alpha-estradiolyl propinol coupled to 1-(4-methylbenzoic acid)1,4,8,11-tetraazacyclotetradecane (CPTA), was compared to Tc-99m-MIBI (methoxyisobutyl isonitrile) in female Albino Wistar rats. Tissues of interest included lung, liver, heart, kidneys, spleen, stomach, intestines, pancreas, muscle, blood, breast, ovary, fat, and uterus. Tc-99m-ESTCPTA uptake by the uterus and ovary, as ER-rich tissues, was highly selective. Maximum uptakes for Tc-99m-MIBI and Tc-99m-ESTCPTA are 90 min in breast, ovary and uterus. The pancreas also showed significant receptor saturated and unsaturated ratios for Tc-99m-ESTCPTA. Results are sufficiently encouraging to generate further evaluation of these and related compounds as possible estrogen receptor based tumor imaging and therapeutic agents in estrogen-rich tissues. (C) 2002 Published by Elsevier Science Ltd.
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    Detecting inflammation with I-131-labeled ornidazole
    (Pergamon-Elsevier Science Ltd, 2000) Asikoglu, M; Yurt, F; Cagliyan, O; Unak, P; Ozkilic, H
    The aim of this study was to demonstrate the accumulation of I-131-labeled ornidazole (I-131-ORN) in experimental abscesses. I-131-ORN was prepared by electrophilic radioiodination of ORN, using radioiodide in the presence of Iodogen(R). An in vivo inflammation model was prepared by intramuscular injection of turpentine into the thigh of rabbits. Four days later I-131-ORN was intravenously administered to rabbits. Serial scintigrams were performed at different periods, using a Sophy DX Gamma Camera. I-131-ORN was visualized at 10 min after injection. I-131-ORN was also administered intraperitoneally to rats with turpentine-induced inflammation, for quantitative biodistribution studies. Counts of selected tissues were taken by a NaI(TI) scintillation detector (gamma counter) after rats were decapitated. The target-to-non-target muscle ratios were 2.5, 2.6, 2.9 and 1.9 at 1, 3, 5 and 24 h, respectively. (C) 2000 Elsevier Science Ltd. All rights reserved.
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    Detection of Splenosis By Radionuclide Scanning
    (British Inst Radiology, 1987) Derin, H; Yetkin, E; Ozkilic, H; Ozekli, K; Yaman, C
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    Doughnut appearance on I-131 MIBG scintigraphy
    (Lippincott-Raven Publ, 1996) Ozcan, Z; Erdem, S; Akin, H; Burak, Z; Ozkilic, H
    The uptake of I-131 MIBG in neuroblastoma is well-established in imaging studies. I-131 MIBG scintigraphy of a patient with neuroblastoma illustrated ''doughnut'' appearance, which is a well-recognized bone scan finding mostly in giant-cell tumor of bone. This finding was probably caused by central necrosis and hemorrhage, and surrounding viable tumor tissue.
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    The Effect of Contraceptives on Lymphocyte Adherence Phenomena
    (Karger, 1982) Aydar, S; Ozkilic, H
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    The Effect of Oral-Contraceptives on Blood-Coagulation
    (Karger, 1982) Derin, H; Ozkilic, H
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    Effect of Pulsatile Flow During Cardiopulmonary Bypass on Thyroid-Hormone Metabolism
    (Elsevier Science Inc, 1994) Buket, S; Alayunt, A; Ozbaran, M; Hamulu, A; Discigil, B; Cetindag, B; Ozkilic, H; Balkan, Z; Bilkay, O; Durmaz, I
    Changes in thyroid hormone levels during and after cardiopulmonary bypass (CPB) are well documented. However, little is known about the effects of pulsatile flow during CPB on thyroid hormone metabolism. To examine the effect of flow pattern, a prospective study was carried out using 30 patients undergoing coronary artery bypass grafting. Fifteen patients had pulsatile flow during CPB and 15, nonpulsatile flow. Serum samples were obtained preoperatively, during bypass, and at 2 and 24 hours postoperatively. Thyroid-stimulating hormone, thyroxine (T-4), triiodothyronine (T-3), free T-4, and free T-3 levels were measured by radioimmunoassay. All measured hormone levels except free T-4 and thyroid-stimulating hormone decreased after the initiation of CPB. There were no differences in preoperative values between the two groups. However, levels of T-3 and free T-3 during and after CPB showed a significant difference between the two groups, with a smaller decrease in patients in whom pulsatile flow was used during bypass (p < 0.05). Thyroxine, and thyroid-stimulating hormone free T-4 values showed no difference between the two groups at any sampling time. These data provide support for the use of pulsatile now during CPB to establish a more physiologic state and maintain better thyroid hormone metabolism.
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    Evaluation of Palpable Breast Masses With Tc-99M-Mibi - a Comparative-Study With Mammography and Ultrasonography
    (Chapman Hall Ltd, 1994) Burak, Z; Argon, M; Memis, A; Erdem, S; Balkan, Z; Duman, Y; Ustun, Ee; Erhan, Y; Ozkilic, H
    We evaluated the feasibility of Tc-99m-methoxyisobutylisonitrile (MIBI) as a tumour localizing agent in patients with palpable breast masses in comparison with mammography and ultrasonography (US). Forty-one patients with palpable masses were studied. An additional 12 women with no palpable breast anomaly also underwent Tc-99m-MIBI breast study. Multiple views were obtained and semiquantitative evaluation was applied. Mammography and US revealed all of the malignant breast masses but differential diagnosis of fibroadenomas could not be achieved. Twenty-five of 27 breast carcinomas were detected using Tc-99m-MIBI scintigraphy. Two patients with invasive lobular carcinoma showed absent MIBI accumulation. Eight of 14 axillary lymph-node metastases showed positive uptake (57%). Twelve of 14 patients with pathologically proven benign breast lesions did not demonstrate any MIBI accumulation. Focal MIBI uptake could be observed in two fibroadenomas. The sensitivity and the specificity of semiquantitative MIBI analysis were 93 and 86%, respectively. Subjective grading offered no additional help in the further differentiation of malignant breast masses. There was no significant difference between histopathological types of breast carcinomas and uptake grades. Our results indicate that Tc-99m-MIBI scintigraphy may provide additional information in the differentiation of malignant pathologies from benign lesions in patients with palpable breast anomalies.
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    False-negative scintigraphy with Tc-99m sestamibi in stage IV neuroblastoma
    (Lippincott Williams & Wilkins, 1999) Ozcan, Z; Erenel, G; Aksoylar, S; Kansoy, S; Burak, Z; Ozkilic, H
    Tc-99m sestamibi, originally developed for myocardial studies, has been used as a tumor-seeking agent. Recently, the agent also was reported to be a functional tracer to predict multidrug resistance-related p-glycoprotein expression in tumor tissue. The current report presents the authors' experience with sestamibi tumor scintigraphy in a neuroblastoma. Although I-131 MIBG tumor imaging and Tc-99m MDP bone scanning accurately demonstrated the extent of the disease, Tc-99m sestamibi showed no accumulation in primary and metastatic foci. Lack of sestamibi uptake was initially thought to be suggestive of failure to respond to chemotherapy because of p-glycoprotein expression. However, the patient responded well to chemotherapy and complete remission was achieved. The failure of Tc-99m sestamibi to detect a neuroblastoma and the lack of sestamibi accumulation in the tumor may not always be related to chemotherapy resistance.
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    Labeling of Diazepam With I-131
    (Akademiai Kiado, 1995) Yurt, F; Unak, P; Ozkilic, H; Tuglular, I
    Diazepam, which aims at benzodiazepine receptors and can be used as a specific SPECT agent has been labeled with [I-131]2-iododiazepam (2-IDZ) was obtained in 50% HCl medium and [I-131]2'-iododiazepam (2'-IDZ) was prepared by the indogen method. The products were purified by passing through a Dowex-1 anion-exchange column.
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    Labeling of zopiclone with iodine-131
    (Elsevier Science Inc, 1999) Yurt, F; Unak, P; Ozkilic, H; Uluc, F; Bagci, S; Tuglular, I
    Zopiclone (ZPC) was labeled with I-131 by using the halogen exchange method. Temperature and reaction time effects to labeling yields were studied, Infrared, nuclear magnetic resonance, and gas chromatography-mass spectroscopy spectra were undertaken to identify chemical structure. High performance liquid chromatography (HPLC) was performed to determine purity of cold zopiclone. Biodistribution studies were performed on rabbits and rats. (131)IZPC was administered intravenously to rabbits. Static images were taken by a Sophy DX Gamma Camera. (131)IZPC was also administered intraperitoneally to rats. Activities were counted in a NaI(Tl) scintillation detector for several organs (liver, brain, spleen, lung, blood, fat) after rats were decapitated on different times. Biodistribution profiles were obtained depending on the time. NUCL MED BIOL 26;7:827-831, 1999. (C) 1999 Elsevier Science Inc. All rights reserved.
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    Papillary microcarcinoma of the thyroid gland: Retrospective analyses of clinical presentation and outcome
    (Springer-Verlag, 2001) Ozcan, Z; Ozkilic, H; Omur, O; Erhamamci, S; Ozyurt, O; Dirlik, A; Kayalioglu, M; Tuncyurek, M
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    Plasma and bronchoalveolar lavage fluid levels of endothelin-1 in patients with chronic obstructive pulmonary disease and pulmonary hypertension
    (Karger, 2003) Bacakoglu, F; Atasever, A; Ozhan, MH; Gurgun, C; Ozkilic, H; Guzelant, A
    Background: Secondary pulmonary hypertension (PH) and cor pulmonale are the major clinical cardiovascular complications affecting prognosis in patients with chronic obstructive pulmonary disease (COPD). It is also known that endothelin-1 (ET-1) is a potent vasoconstrictor peptide produced by the pulmonary vascular endothelium, and ET-1 may be implicated in the pathogenesis of PH. Objectives: The purpose of this study was to investigate the presence of ET-1 in patients with COPD and to assess the correlation of ET-1 levels in the plasma and bronchoalveolar lavage (BAL) fluid (BALF) in COPD patients with or without PH. Methods: Twenty-two patients with COPD and 15 healthy controls were enrolled in the study. Peripheral venous blood samples were collected in all patients and controls. BAL was obtained in COPD patients, and ET-1 levels were measured by radioimmunoassay in all plasma and BALF samples. Results: Plasma ET-1 levels were 2.46 +/- 0.55 and 1.70 +/- 0.42 pmol/dl in patients with COPD and controls, respectively (p < 0.0001). Sixteen of the 22 patients with COPD (73%) had PH established by echocardiography. The ET-1 level in these patients amounted to 2.59 +/- 0.50 pmol/dl, and it was 2.10 +/- 0.54 pmol/dl in 6 patients with COPD without PH. In COPD patients with and without PH, BALF ET-1 levels were 0.19 +/- 0.08 and 0.24 +/- 0.01 pmol/dl, respectively (p > 0.05). Conclusions: These results suggest that ET-1 is detectable in both the peripheral blood and BALF of COPD patients, but the levels do not statistically differ between patients with and without PH. Copyright (C) 2003 S. Karger AG, Basel.
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    The results of radioiodine therapy in patients with hyperthyroidism after one year follow up
    (Springer-Verlag, 2001) Argon, M; Ozyurt, O; Kumanlioglu, K; Ozkilic, H
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    The role of Tc-99(m)-sestamibi scintigraphy in the staging and prediction of the therapeutic response of stage IV neuroblastoma: Comparison with I-131-MIBG and Tc-99(m)-MDP scintigraphy
    (Lippincott Williams & Wilkins, 1999) Burak, Z; Yuksel, DA; Cetingul, N; Kantar, M; Ozkilic, H; Moretti, JL
    In this study, we investigated prospectively the diagnostic role of Tc-99(m)-MIBI for staging and for predicting the therapeutic response of stage nr neuroblastoma compared wth I-131-MIBG imaging and Tc-99(m)- MDP bone scintigraphy. Nine patients (4 girls and 5 boys aged 1-7 years) with suspected or proven stage IV neuroblastoma were studied with Tc-99(m)-MIBI at initial diagnosis and after 12-18 months of multidrug therapy. After the injection of 80 MBq.kg(-1) Tc-99(m)-MIBI, early (10 min) and delayed (1 h) images were obtained. The data were correlated with I-131-MIBG scans, bone scintigraphy, ultrasound, computed tomography and/or magnetic resonance imaging, and bone marrow biopsy. Eight of nine primary tumours and 41 metastatic lesions were detected by I-131-MIBG scintigraphy. None of the primary lesions demonstrated significant Tc-99(m)-MIBI accumulation. Sestamibi was positive in 16 of 41 MIBG-avid metastatic lesions. After six courses of multidrug chemotherapy, 30 I-131-MIBG-avid neuroblastoma metastases that were Tc-99(m)-MIBI-negative at the time of diagnosis still did not show significant sestamibi accumulation. Follow-up demonstrated that all lesions that were Tc-99(m)-MIBI-avid at the time of diagnosis remained negative. Of these 16 lesions, seven were positive for I-131-MIBG accumulation with no reduction in size, and nine showed resolution after therapy. New metastatic foci detected by MIBG scintigraphy did not accumulate Tc-99(m)-MIBI. Clinical evaluation of patients with no Tc-99(m)-MIBI uptake in primary and secondary sites of neuroblastoma confirmed that they were resistant to multidrug chemotherapy. AII Tc-99(m)-MIBI-positive lesions, irrespective of clinical outcome, demonstrated significant clearance of tracer on the delayed images. We conclude that Tc-99(m)-MIBI has no role in the staging of neuroblastoma. Sestamibi is a well-documented transport substrate for P-glycoprotein-related multidrug resistance and serial imaging may provide prognostic information on the therapeutic value of chemotherapy. ((C) 1999 Lippincott Williams & Wilkins).
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    Scanning the Thyroid With Technetium-99M-Pertechnetate
    (Soc Nuclear Medicine Inc, 1992) Derebek, E; Ozkilic, H