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Öğe Alteration of intestinal permeability in patients with gynecologic cancers treated with pelvic radiotherapy(Springer-Verlag, 2001) Dirlik, A; Taner, M; Erhamamci, S; Ozcan, Z; Karadogan, I; Esassolak, MÖğe Brain SPECT in anterior opercular syndrome due to a unilateral lesion(Springer Verlag, 1996) Kutluay, E; Colakoglu, Z; Dirlik, A; Kumral, KÖğe Clinical-Evaluation of Metastases of Malignant-Melanoma Imaging With Tc-99(M)-Glutathione and Tc-99(M)-Anti-Melanoma Antibody - a Comparative-Study(Chapman Hall Ltd, 1995) Duman, Y; Burak, Z; Ercan, Mt; Dirlik, A; Bilkay, Bc; Akin, Y; Taner, M; Bekdik, CfThe aim of this investigation was to test for the scintigraphic detection of metastases of malignant melanoma with a new radiopharmaceutical, Tc-99(m)-glutathione (Tc-99(m)-GSH), in comparison with Tc-99(m)-anti-melanoma antibody (Tc-99(m)-AMAb). Glutathione was labelled with Tc-99(m) by a Sn2+ reduction method with an efficiency of > 99% as determined by instant thin layer chromatography (ITLC). Anti-melanoma antibody was obtained as a kit from SORIN (Italy) and labelled with (TcO4-)-Tc-99-O-m. Forty-three patients with a total of 55 biopsy-proven metastatic melanoma foci, 1 ocular melanoma and 20 benign pathologic foci, also confirmed by ultrasound, computed tomography and magnetic resonance imaging, were included in the study after giving their informed consent. Following the intravenous (i.v.) injection of 500 MBq Tc-99(m)-AMAb, scintigraphic images of the involved areas were obtained 6 h post-injection. Three days later, the same patients were given 500 MBq Tc-99(m)-GSH i.v, and images were obtained 6 and 24 h post-injection. The images were classified as positive (focal abnormal accumulation) or negative. Quantitative evaluation was also applied. Regions of interest were drawn over the involved areas and nearby soft tissues and the target-to-nontarget (T/NT) ratios obtained with Tc-99(m)-AMAb (T/NT: 1.92 +/- 0.2) and Tc-99(m)-GSH (T/NT: 1.84 +/- 0.2) were compared (0.1 < P less than or equal to 0.3). The sensitivity (and specificity) of Tc-99(m)-AMAb and Tc-99(m)-GSH in the detection of malignant melanoma metastases were 91% (95%) and 84% (90%), respectively. Compared with Tc-99(m)-AMAb, the advantages of Tc-99(m)-GSH are lower levels of blood radioactivity, lower costs and easy in-house preparation. In conclusion, our results show that Tc-99(m)-GSH is a potentially useful radiopharmaceutical for the detection of metastases of malignant melanoma.Öğe 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, HÖğe 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, HTechnetium-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).Öğe Evaluation of Bladder Functions With Radionuclid Studies (Tc-99M-Dtpa) In Diabetic-Patients(Springer Verlag, 1992) Atalay, M; Akalin, E; Kabalak, T; Dirlik, A; Alper, A; Duman, YÖğe Exercise Whole-Body Tl-201 Scintigraphy In Patients With Insulin-Dependent Diabetes-Mellitus(Springer Verlag, 1992) Derebek, E; Duman, Y; Ozmen, B; Burak, Z; Erdem, S; Kayalioglu, M; Dirlik, A; Unlu, MÖğe Labeling of Gly-Gly-L-Alanine with Technetium-99m and the assessment of it's radiopharmaceutical potential(Springer-Verlag, 2001) Taner, MS; Ozdemir, D; Koseoglu, K; Argon, M; Dirlik, A; Duman, YÖğe Moyamoya Disease In Twins(Lippincott Williams & Wilkins, 1995) Duman, Y; Dirlik, A; Burak, Z; Tutuncu, STc-99m HMPAO SPECT was used to evaluate regional blood Row in one monozygotic twin who had angiographically proven moyamoya disease, Focal and global reduced regional cerebral perfusion were observed in both patients with Tc-99m HMPAO SPECT studies. There was good correlation between the localization end degree of regional cerebral blood flow abnormalities and the severity and stage of clinical symptoms on angiography. These results suggest that Tc-99m HMPAO SPECT is a useful method in the detection of hemodynamic abnormalities in moyamoya disease.Öğe 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, MÖğe The role of Tc-99m MIBI imaging in the assessment of drug resistance in musculo-skeletal tumors.(Springer Verlag, 1999) Burak, Z; Erinc, R; Ozcan, Z; Ersoy, O; Basdemir, G; Dirlik, A; Sabah, D; Moretti, JLÖğe The role of Tc-99m sestamibi imaging in predicting clinical response to chemotherapy in lung cancer(Japanese Society Nuclear Medicine, 2002) Dirlik, A; Burak, Z; Goksel, T; Erinc, R; Karakus, H; Ozcan, Z; Veral, A; Ozhan, MMultidrug resistance (MDR) is a major problem in lung cancer. Tc-99m methoxyisobutyl isonitrile (MIBI) has been demonstrated to be a non-invasive marker to diagnose MDR1 related P-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP) expression in various solid tumors. The aim of this study was to evaluate the relationship between the degree of Tc-99m MIBI uptake and its retention on delayed images and the response to chemotherapy in lung cancer. Twenty-three patients (I woman and 22 men, age range 40-67 years) with lung cancer (9 small cell and 14 non-small cell) were examined with Tc-99m MIBI imaging before chemotherapy. After i.v. administration of 740 MBq Tc-99m MIBI, planar and SPECT imaging at 30 minutes and 2 hours was performed. Tumor to normal lung uptake ratio (T/N) and percent retention were measured, Response to chemotherapy was evaluated according to follow-up CT and grouped as complete responders (CR), partial responders (PR) and non-responders (NR). Clinical follow-up and CT evaluation revealed that 12 patients had partial remission, 4 patients had complete remission and 7 patients had no-remission after chemotherapy. Statistically, there was no significant correlation between early (30 min), delayed (2 hr) T/N ratios and percent retention of Tc-99m MIBI with chemotherapeutic response of the lung cancer among the three groups (p > 0.05). Results of the cur-rent study imply that Tc-99m MIBI uptake and the retention index may not correlate with chemotherapy response in lung cancer, so that the accuracy of this method needs to be verified in a larger series with additional investigation at the molecular level.Öğe The role of Tc-99m-MIBI scintigraphy in the assessment of MDR1 overexpression in patients with musculoskeletal sarcomas: comparison with therapy response(Springer-Verlag, 2001) Burak, Z; Ersoy, O; Moretti, JL; Erinc, R; Ozcan, Z; Dirlik, A; Sabah, D; Basdemir, GThe occurrence of multidrug resistance (MDR), which is in part due to the overexpression of P-glycoprotein (Pgp), is a major problem in neoadjuvant therapy of malignant musculoskeletal tumours. The aim of this study was to investigate the role of technetium-99m hexakis-2-methoxyisobutylisonitrile (Tc-99m-MIBI) scintigraphy for functional imaging of the MDR1 phenotype in patients with musculoskeletal sarcomas. We aimed to compare Tc-99m-MIBI uptake and washout kinetics with the expression of Pgp and with chemotherapy response. Twenty-five patients (16 males and 9 females, aged between 8 and 65 years) with malignant musculoskeletal tumours were studied. After injection of 555-740 MBq Tc-99m-MIBI, dynamic flow images of the involved area were obtained for 3 min, and planar images were acquired at 10 min and I h. From the dynamic images, a tumour perfusion index (TPI) was obtained using Patlak-Rutland analysis. Tumour to background (T/B) ratios of both early and delayed images and percent wash-out rate (WR%) of Tc-99m-MIBI were calculated. Immunohistochemical analysis of Pgp was performed on biopsy specimens and the degree of expression was graded according to a semiquantitative scoring system, from 0 to 6. After neoadjuvant therapy, tumour response was assessed by examining the ratio of viable cells and by detecting percent necrosis. Scintigraphic results were compared with Pgp status and therapy response. Irrespective of the Pgp status, all patients showed significant perfusion and Tc-99m-MIBI uptake in early images. There was not a significant correlation between T/B ratios of early and delayed images and Pgp expression. We observed a positive correlation between WR% and Pgp status (r=0.61, P <0.01), and the wash-out rate of Tc-99m-MIBI was significantly higher in patients with high Pgp expression than in those with a low Pgp score (33%+/-9% vs 17%+/-9%). Therapy response was determined in 21 of 25 patients, and in only 5 of 21 cases was the percent necrosis more than 90%. Neither Pgp expression rate nor WR% was found to show a significant correlation with percent necrosis in the bulk tumour specimens. In conclusion, the initial uptake of Tc-99m-MIBI in bone and soft tissue sarcomas did not correlate with Pgp expression. A relationship was found between the wash-out rate of Tc-99m-MIBI and the Pgp score, with a significant difference in WR% being observed between patients with high and patients with low Pgp expression.Öğe The role of Tc99m sestamibi imaging in predicting clinical response to chemotherapy in lung cancer(Springer Verlag, 1999) Dirlik, A; Erinc, R; Goksel, T; Argon, M; Karakus, H; Ozhan, M; Burak, ZÖğe Tc-99m DMSA localization in infantile hemangioma(Lippincott Williams & Wilkins, 2002) Dirlik, A; Ozcan, Z; Ozbek, SS; Karapinar, B; Ozyurt, O; Cura, AThe authors describe a neonate with bilateral dysplastic kidneys who underwent Tc-99m DMSA scintigraphy for the assessment of renal cortical functions. Although poor renal uptake was noted on the Tc-99m DMSA scan, an unusual area of soft tissue accumulation was detected in the right hypochondrium. A color Doppler study confirmed the diagnosis of soft tissue hemangioma as the cause of extrarenal Tc-99m DMSA accumulation, which has not been reported before. Poor renal function resulting in high blood-pool activity of Tc-99m DMSA may lead to extrarenal localization of the tracer in infantile hemangioma.Öğe Tc99m pertechnetate whole body scanning in differentiated thyroid carcinoma in comparison with I-131 whole body scintigraphy(Springer-Verlag, 2001) Dirlik, A; Kayalioglu, M; Erhamamci, S; Omur, O; Ozcan, Z; Kumanlioglu, K; Ozkilic, HÖğe Technetium-99m-DTPA aerosol scintigraphy in amiodarone induced pulmonary toxicity in comparison with Ga-67 scintigraphy(Japanese Society Nuclear Medicine, 2002) Dirlik, A; Erinc, R; Ozcan, Z; Atasever, A; Bacakoglu, F; Nalbantgil, S; Ozhan, M; Burak, ZAmiodarone hydrochloride, which is used in life-threatening cardiac tachyarrhythmia, has been known to cause amiodarone induced pulmonary toxicity (AIPT) as a complication. In this study we aimed to investigate the clinical value of technetium-99m diethylene triamine penta-acetic acid (DTPA) aerosol lung scintigraphy in patients with AIPT in comparison with gallium-67 (Ga-67) scan. The study group included 26 cases, 7 patients with diagnosis of AIPT (Group A), 8 patients receiving amiodarone therapy but without AIPT (Group B) and I I healthy subjects as a control group (Group Q. All patients underwent Ga-67 and Tc-99m-DTPA aerosol scintigraphy in addition to various laboratory tests, Ga-67 scintigraphy was positive in 4 of 7 AIPT patients but quite normal in Group B. A positive correlation was found (r = 0.52, p < 0.05) between kep values determined by Tc-99m-DTPA aerosol scintigraphy and the cumulative dose of amiodarone. The mean kep values were 2.04% +/- 0.85%/min, 1.30% +/- 0.42%/min and 0.86% +/- 0.19%/min for groups A, B and C, respectively. ne mean clearance rate of group A was significantly faster than that of normals (p < 0.0005) and group B (p = 0.028). In addition, there was a significant difference between groups B and C (p = 0.015). In conclusion, Ga-67 lung scintigraphy is a useful method for the detection of AIPT but Tc-99m-DTPA aerosol scintigraphy offers better results than Ga-67 scintigraphy. Early changes in Tc-99m-DTPA clearance may be observed in patients receiving amiodarone. The kep value in patients with AIPT is noticeably increased with respect to the control group. With its favorable physical properties, low cost, lower radiation burden and its ability to be used as an objective measure for the pulmonary clearance rate, Tc-99m-DTPA aerosol scintigraphy appears to be promising in patients receiving amiodarone therapy.Öğe Tl-201 Spect Following Dobutamine Infusion For the Detection of Coronary-Artery Disease In Patients With Low Ejection Fraction Rates(Springer Verlag, 1992) Duman, Y; Dirlik, A; Unlu, M; Kayalioglu, M; Kirman, M; Durmaz, IÖğe The value of Tl-201 scan in the evaluation of suspected thymic rebound phenomenon(Springer Verlag, 1999) Bilkay, U; Burak, Z; Dirlik, A; Kantar, M; Omur, O; Cetingul, N; Duman, Y
