Hakan Demir

Kocaeli University, Kocaali, Sakarya, Turkey

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Publications (29)60.81 Total impact

  • Article: Reduced heart rate response to dipyridamole in patients undergoing myocardial perfusion SPECT.
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    ABSTRACT: A mild decrease in blood pressure and increase in heart rate (HR) are considered normal hemodynamic responses to dipyridamole. In this study, we tried to investigate HR response to dipyridamole and its predictors in patients undergoing gated myocardial perfusion single photon emission computed tomography (SPECT). 201 consecutive patients undergoing dipyridamole stress Tc99m-MIBI or Tl-201 gated myocardial perfusion SPECT were prospectively enrolled. Dipyridamole was infused over 4 min and radiopharmaceutical was injected 3 min after the end of infusion. A reduced heart rate response to dipyridamole considered if the HR ratio (peak HR/rest HR) was 1.20 or less. Stress (sLVEF), rest (rLVEF) left ventricular ejection fractions, stress and rest motion (SMS, RMS) and thickening scores (STS, RTS) were derived automatically by QGS. Summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) for myocardial perfusion were calculated. Patients were grouped according to HR response and groups were compared. A logistic regression analysis was used to determine independent predictors of reduced HR response. Reduced HR response was found in 78 % of patients. Patients with abnormal HR response were more frequently had a history of diabetes mellitus, chronic renal failure, and had lower high-density lipoprotein (HDL) levels. Peak HR, SSS, SRS, sLVEF and rLVEF were lower; rest HR, RTS, and the number of patients with ≤45 % sLVEF and rLVEF were higher in reduced HR response group (all p < 0.05). There was no difference between groups by means of gender, rest and peak systolic or diastolic tension, SDS, SMS, STS, RMS, history of hypertension, peripheral arterial disease, metabolic syndrome, coronary interventions, digoxin, calcium channel blocker or beta blocker usage. Multivariable logistic regression analysis demonstrated that the independent predictors of reduced HR response were HDL, rest HR and SSS. When HDL was removed from the model, chronic renal failure also emerged as an independent predictor. Reduced HR response to dipyridamole is associated with ventricular dysfunction, cardiac autonomic neuropathy. Low HDL levels also seem to be related with reduced HR response.
    Annals of Nuclear Medicine 06/2012; 26(8):609-15. · 1.50 Impact Factor
  • Article: Radioiodine therapy in Graves' disease: is it possible to predict outcome before therapy?
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    ABSTRACT: To assess the predictability of outcome and evaluate the factors that may lead to treatment failure in patients with Graves' disease who are treated with a single dose of radioiodine. This is a retrospective study of 123 patients (M: 42; F: 81) with Graves' disease who received radioiodine therapy with a single fixed (10 mCi) dose for hyperthyroidism. Pretreatment age, sex, BMI, type of anti-thyroid drug used, propylthiouracil doses, iodine uptake, uptake ratio (4/24 h radioiodine uptake), and thyroid volume of the patients in whom radioiodine therapy succeeded or failed were compared. Post-therapy follow-up revealed that therapy failed in 22% of the patients. Iodine uptakes and uptake ratios and volumes were found to be significantly higher in patients in whom therapy failed. It was observed that uptake ratio was at least 1 in 25 patients (20%), and therapy failed in 20 (80%) of these patients. Of the 98 patients (80%) in whom uptake ratio was less than 1, therapy was unsuccessful in only seven (7%). Uptake ratio is a simple index that may be used to predict the patients in whom therapy may fail or succeed. In patients with Graves' disease who have an uptake ratio of less than 1, radioiodine appears to be an effective dose with high success rates. In contrast, because of the high rates of failure in patients with an uptake ratio of at least 1, use of radioiodine therapy at a dose of 10 mCi does not seem to be appropriate.
    Nuclear Medicine Communications 06/2012; 33(8):859-63. · 1.40 Impact Factor
  • Article: Subhyoid ectopic thyroid with mediolateral location in a developmentally retarded child with hypothyroidism in an iodine deficiency region
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    ABSTRACT: The authors present a case of subhyoid ectopic thyroid with mediolateral location diagnosed by technetium-99m pertechnetate scan. The ectopia was associated with hypothyroidism and developmental retardation.
    Annals of Nuclear Medicine 04/2012; 16(7):483-486. · 1.50 Impact Factor
  • Article: Graves' disease in a patient with ectopic mediastinal thyroid.
    Clinical nuclear medicine 11/2011; 36(11):1039-40. · 3.92 Impact Factor
  • Article: Sentinel lymph node biopsy with a gamma probe in patients with high-risk cutaneous squamous cell carcinoma: follow-up results of sentinel lymph node-negative patients.
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    ABSTRACT: Lymphoscintigraphy (LS) and sentinel lymph node biopsy have become the standard of care for melanoma and breast cancer. However, the data on patients with cutaneous squamous cell carcinoma (SCC) are limited. We aimed to evaluate and identify the role of LS and sentinel lymph node biopsy in patients with high-risk cutaneous SCC. Nineteen patients (13 men, six women; 47-87 years of age, mean age 67.5 ± 12.3) with SCC were included in the study. LS was performed on all patients after intracutaneous injection of Tc-99m nanocolloid. Primary lesions and sentinel lymph nodes (SLNs) were excised with the help of a gamma probe. A total of 26 SLNs and 32 secondary lymph nodes were imaged on LS and were marked. During surgery, 29 SLNs, 21 secondary lymph nodes and three nonactive lymph nodes were excised. In total, 53 lymph nodes were removed surgically. A histopathological study revealed that all lymph nodes were negative for metastasis. Patients were followed up for an average of 41.1 ± 22.2 months (7-80 months). Until the time of data collection, 14 patients were alive and had no regional lymph node or distant metastasis. Local recurrence was seen in only one patient. He was reoperated upon 38 months ago. The feasibility of determining SLNs using LS and an intraoperative gamma probe in patients with cutaneous SCC was shown. Unnecessary elective lymph node dissection and possible complications could be avoided in 19 patients.
    Nuclear Medicine Communications 09/2011; 32(12):1216-22. · 1.40 Impact Factor
  • Article: Peel bond strength of two silicone soft liners to a heat-cured denture base resin.
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    ABSTRACT: This study investigated the peel strength of two different soft liners to a polymethylmethacrylate (PMMA) denture base resin before and after thermocycling. The silicone-based soft liner materials tested were Molloplast B and Permaflex; the denture base material was a heat-cured acrylic resin, Meliodent. A total of 40 specimens was prepared using rectangular molds with dimensions of 100 x 10 x 2 mm for PMMA and 150 x 10 x 2 mm for soft liners, as described in ASTM-D903-93. For each of the liner materials, 10 specimens were packed against a cured PMMA denture base surface as recommended by the manufacturers. The other 10 specimens were packed against PMMA denture base dough and processed together. In each group, 5 of the specimens were tested directly, while the other 5 were thermocycled in a water bath (5°C to 55°C; 3000 cycles) before testing. Peel testing was performed using an Instron testing machine. The results revealed that peel strength values of the Permaflex specimens prepared according to the manufacturer's recommendations were significantly higher than those of Molloplast B (p < 0.05). However, when packing was done against uncured PMMA dough, the difference between the specimens of two liners was not significant. Thermocycling led to significant decreases in the peel strength of both Permaflex liner specimens packed against cured/uncured PMMA resin surfaces (p < 0.05), whereas this process did not affect the strength of Molloplast B specimens. Results indicated that the material Molloplast B was superior to the material Permaflex in terms of peel strength when the specimens were simultaneously polymerized with PMMA and thermocycled.
    The journal of adhesive dentistry 06/2011; 13(6):579-84. · 1.11 Impact Factor
  • Article: The bond strength of a highly cross-linked denture tooth to denture base polymers: a comparative study.
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    ABSTRACT: This study compared shear bond strength and type of bond failure between a highly cross-linked tooth and different denture base polymers. Cross-linked denture teeth were bonded to either a heat-, an auto-, a microwave-polymerized denture base resin or a relatively new injection-molded, microwave-polymerizable polyurethane-based resin. Six experimental groups were established for each of the shear and peel tests. In four of the groups, teeth were used as received and bonded to each of the denture base resins; in the remaining two groups, they were treated with dichloromethane to determine its effect on the bonding with heat or auto-polymerized denture base resins. Bond strength was determined by compressive load applied at 45 degrees on the palatal surface of each tooth until fracture; the type of bond failure was assessed by the peel test. The results showed that heat-cured PMMA groups failed cohesively and demonstrated significantly higher bond strengths than the other resins used. The application of dichloromethane on the ridge lap areas of teeth resulted in a significant improvement of bond strengths in heat- and auto-cured resins. Within the limitations of this experimental study, the results suggest that type of denture base material and processing methods may have an influence upon the bond strength between interpenetrating polymer network (IPN) denture teeth and base materials. Treatment of denture teeth with dichloromethane could provide substantial improvement in the bond strength of teeth with heat and auto-cured denture base resins; however, this finding should be validated in further investigations on the long-term effect of such treatment on the bond strength.
    The journal of adhesive dentistry 02/2011; 13(1):85-92. · 1.11 Impact Factor
  • Article: Obesity control and low protein diet preserve or even improve renal functions in Bardet-Biedl syndrome: a report of two cases.
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    ABSTRACT: Bardet-Biedl syndrome (BBS) is a rare autosomal-recessive disorder characterized by abdominal obesity, mental retardation, dysmorphic extremities, retinal dystrophy, hypogonadism, and kidney structural abnormalities or functional impairment. It is now considered a significant cause of chronic and end-stage renal disease in children. To the best of our knowledge there have been no previous studies on the role of diet in the management of renal functions in patients with BBS. Two siblings, aged 32 and 27 years, with BBS are presented. On admission both patients were obese, with body mass indexes (BMI) of 40 and 39 kg/m2. Their creatinine clearances (CrCl) were 41 and 24 mL/min. After 2 years of follow-up with a diet consisting of 0.6 g/kg/day protein and 1400 kcal/day energy, their BMI's were decreased to 29 and 27 kg/m2, whereas their CrCl's were increased to 44 and 32 mL/min, respectively. 99mTc-MAG3 scintigraphy also revealed improved renal function. Since this syndrome most likely results in end-stage renal disease, follow-up of renal dysfunction is essential. Low protein diet and/or obesity control may slow the progression of renal failure in patients with BBS.
    Medical science monitor: international medical journal of experimental and clinical research 01/2011; 17(1):CS12-14. · 1.70 Impact Factor
  • Article: Effect of maleic anhydride pretreatment on tensile bond strength of a silicone soft liner to a denture base polymer.
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    ABSTRACT: To determine the effect of resin surface treatment with dissolved maleic anhydride in butanone added into primer on the tensile bond strength between an acrylic denture base resin and a silicone soft liner. To test tensile bond strength, standard dumbbell-shaped acrylic specimens were prepared. Five experimental groups, including the control, were tested (n = 5). Maleic anhydride solutions prepared in butanone at concentrations of 1%, 5%, 10% or 20% were then mixed with 1 ml of Primo adhesive and the mixtures were applied onto the resin bonding surfaces. Silicone liner material was applied to resin surfaces in the conventional manner. Tensile bond strength of the specimens was measured in a universal testing machine. Fractured surfaces were observed under the scanning electron microscope, and resulting chemical changes with the solutions used were analyzed spectroscopically. The highest bond strength value was obtained for the group treated with 5% maleic anhydride (2.53 ± 0.48 MPa); the lowest value was for the group treated with 20% maleic anhydride (1.59 ± 0.29 MPa). Mixed failure was the dominant type seen in the experimental groups. Spectroscopic analysis showed the interaction of the anhydride carbonyl groups with the Primo primer. The treatment of resin surfaces with maleic anhydride added to Primo adhesive effectively increased bond strength between silicone soft liner and denture base resin.
    The journal of adhesive dentistry 11/2010; 13(5):481-7. · 1.11 Impact Factor
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    Article: A child with undifferentiated sarcoma of the liver complicated with bronchobiliary fistula and detected by hepatobiliary scintigraphy.
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    ABSTRACT: Undifferentiated (embryonal) sarcoma of the liver (USL) is a rare malignant mesenchymal tumor principally affecting patients of pediatric age. Bronchobiliary fistula is a very rare complication in patients with liver tumor. To the authors' knowledge, this is the first report of a bronchobiliary fistula resulting from tumor invasion in a child with liver sarcoma. A 12-year-old boy was diagnosed to have USL of the right liver lobe, invading the diaphragm. An extended right hepatectomy and total resection of the mass was performed, leaving patchy tumoral invasion of the anterior diaphragmatic surface followed by combined chemotherapy regimen. Six months after the operation, the presence of bilious sputum suggested a bronchobiliary fistula, which was confirmed by hepatobiliary scintigraphy. The patient underwent a right thoracotomy and fistula division. Although bronchobiliary fistula is a very rare complication in patients with hepatic tumors, suspicion in the appropriate clinical setting is necessary to recognize this problem. Hepatobiliary scintigraphy is the useful diagnostic procedure to define bronchobiliary fistula in children with liver tumor and clinical suspicion of bronchobiliary fistula.
    Pediatric Hematology and Oncology 07/2009; 21(5):427-33. · 0.89 Impact Factor
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    Article: Temperature rise induced by various light curing units through human dentin.
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    ABSTRACT: This study investigated temperature rises caused by different light curing units (LCUs) in dentin of different thicknesses. The different LCUs tested in this study were namely: quartz-tungsten-halogen (QTH) (Heliolux DLX) LCU, plasma arc (PAC) (Apollo 95E Elite) LCU, and light emitting diode (LED) (Mini LED) in standard curing mode as well as pulse and soft-start modes. One hundred and forty dentin disks of 0.5, 1, 1.5, and 2 mm thickness were prepared from mandibular molars (n=7). Temperatures were recorded using a L-type thermocouple in direct contact with the light guide tip. For all curing units/modes, dentin thickness was inversely proportional to temperature rise and that QTH light gave significantly higher values compared to PAC and LED in all the test conditions. The highest temperature rise was observed under 0.5-mm-thick dentin disk with QTH, whereas the lowest temperature rise was registered with LED light in pulse mode under 2-mm-thick dentin.
    Dental Materials Journal 06/2009; 28(3):253-60. · 1.14 Impact Factor
  • Article: Surgical experience in a baby with congenital broncho-biliary fistula.
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    ABSTRACT: Congenital tracheobiliary and bronchobiliary fistulae are rare malformations in which patent communications exist between the respiratory system and biliary tract, respectively. We present a newborn who was admitted with respiratory distress and bilious tracheal discharge. Investigation revealed a bronchobiliary fistula originating from the left main bronchus, as well as biliary atresia. Excision of the bronchobiliary fistula was successful and the connection between biliary tract and gastrointestinal system was established by performance of a Roux-en-Y cholecysto-jejunostomy. Diagnostic tools, differential diagnosis, and surgical correction strategies are discussed.
    The Annals of thoracic surgery 02/2009; 87(1):318-20. · 3.74 Impact Factor
  • Article: A doughnut sign of a hydatid cyst of the liver on F-18 FDG PET/CT.
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    ABSTRACT: A 59-year-old man underwent a whole-body PET/CT scan to evaluate the metabolic activity of a nodule in the upper lobe of the left lung seen on CT. Slightly increased peripheral activity with a large hypometabolic region centrally, a so-called doughnut sign, was seen in the right lobe of the liver. After the diagnosis of a hydatid cyst of the liver, the patient underwent surgery. This case demonstrates a hydatid cyst that caused increased F-18 FDG uptake as a doughnut pattern.
    Clinical nuclear medicine 01/2009; 33(12):876-7. · 3.92 Impact Factor
  • Article: Comparison of exercise and pharmacological stress gated SPECT in detecting transient left ventricular dysfunction.
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    ABSTRACT: Transient left ventricular contractile dysfunction (TLVD) is observed owing to post-exercise stunning in patients with coronary artery disease (CAD). Pharmacological stimulation differs from exercise stress because it does not cause demand ischemia. The aim of this study was to determine whether TLVD could also be seen after pharmacological stress (dipyridamole). Of the patients in whom gated single-photon emission computed tomography (GSPECT) was performed in our institution from January 2004 to April 2007, 439 subjects with known or suspected CAD were included in the study. GSPECT was performed for all patients following exercise (group I, n = 220) or pharmacological stress (group II, n = 219) according to a 2-day (stress-rest) protocol after injection of Tc-99m methoxyisobutyl-isonitrile (MIBI). Stress, rest, and difference (stress-rest value) left ventricular ejection fractions (SLVEF, RLVEF, and DLVEF) and transient ischemic dilatation (TID) ratio were derived automatically. Summed stress score, summed rest score, and summed difference score (SDS) for myocardial perfusion were calculated using a 20-segment model and a five-point scoring system. An SDS > 3 was considered as ischemic. On the basis of the perfusion findings, patients were subdivided into a normal (group A, n = 216) and ischemia group (group B, n = 223). DLVEF and perfusion scores of all groups were compared. Relationships between DLVEF and perfusion, and between TID ratio and DLVEF were also evaluated. Stress-induced ischemia was observed in 223 of 439 patients (50.8%). In group A, the difference between stress and rest LVEF values was not significant (P = 0.670 and P = 0.200 for groups IA and IIA, respectively). However, LVEF was significantly decreased after stress compared with rest values for group B (P < 0.0001 for groups IB and IIB). TLVD (< or =-5% for DLVEF) was observed in 20 of 216 (9%) and 81 of 223 subjects (36%) in patients in groups A and B, respectively (P < 0.0001). In group I, we found TLVD in 46 of 119 (39%) and 12 of 101 (12%) subjects, in patients with and without ischemia, respectively (P < 0.0001). On the other hand, in group II, TLVD was detected in 35 of 104 (34%) and 8 of 115 (7%) patients with and without ischemia, respectively (P < 0.0001). And also, we found significant good correlations between TID ratios and DLVEF values in four subgroups (r = -0.55, r = -0.62, r = -0.59, and r = -0.41; for groups IA, IB, IIA, and IIB, respectively, P < 0.0001 for all). Dipyridamole is believed to be less likely than exercise to induce ischemia. However, in this study, TLVD after stress was observed following not only exercise but also pharmacological stress, consistent with ischemia.
    Annals of Nuclear Medicine 06/2008; 22(5):403-9. · 1.50 Impact Factor
  • Article: FDG PET/CT findings in primary hyperparathyroidism mimicking multiple bone metastases.
    European journal of nuclear medicine and molecular imaging 04/2008; 35(3):686. · 4.99 Impact Factor
  • Article: Evaluation of post-stress left ventricular dysfunction and its relationship with perfusion abnormalities using gated SPECT in patients with cardiac syndrome X.
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    ABSTRACT: Cardiac syndrome X defines patients with typical angina, a positive exercise ECG stress test and angiographically documented normal coronary arteries. In previous studies, post-stress prolonged left ventricular dysfunction (PLVD) using gated SPECT (G-SPECT) had been well correlated with myocardial perfusion abnormalities and degree of stenotic vessels in CAG in patients with coronary artery disease. However, evaluation of left ventricular myocardial perfusion, wall motion and left ventricular ejection fraction (LVEF) in patients with cardiac syndrome X, using G-SPECT had not been studied yet. Thus, the aim of this study was to analyse PLVD using (99m)Tc-MIBI GSPECT in patients with cardiac syndrome X. Of the patients in whom G-SPECT was performed in our institution between 2004 and 2006, 17 patients with anginal chest pain, positive exercise ECG stress test and normal coronary angiograms were retrospectively included to the study (group I). Fifteen patients with normal myocardial perfusion and another 15 patients with ischaemia on G-SPECT were selected as control groups (groups II and III). (99m)Tc-MIBI G-SPECT was performed for all patients according to 2 day (stress-rest) protocol. Stress and rest LVEF were derived automatically (SLVEF and RLVEF). Difference LVEF (DLVEF) (stress-rest) was calculated. Semiquantitative analyses were made both for myocardial perfusion and wall motion (WM), using a 20-segment model and a 5-point scoring system. DLVEF, perfusion and WM scores of all groups were compared among three groups and relationship between DLVEF, perfusion and WM scores were evaluated. Abnormal perfusion were detected in eight (47.1%) of patients, while the remaining nine (52.9%) had normal myocardial perfusion, in group I. Six of 17 (35.3%) patients in group I had post-stress WM abnormalities. Mean of DLVEF values were -3.1+/-3.0%, 4.4+/-2.0% and -6.0+/-5.1% in groups I, II and III, respectively (P<0.05 for group II vs. group I and group III; P>0.05 for group I vs. group III). LVEF response impairment (< or =5% increase from rest to post-stress images) was found in 17 (100%), seven (46.6%), 14 (93.3%) of patients in groups I, II and III, respectively. Abnormal myocardial perfusion, concordant transient segmental WM abnormalities and LVEF response impairment are not uncommon in patients with cardiac syndrome X of this cohort of the study population. Therefore, post-stress prolonged stunning may be attributed to these findings in some of cardiac syndrome X patients as in true ischaemic patients. However, further studies with larger number of subjects and long-term follow-up are necessary to support these findings.
    Nuclear Medicine Communications 03/2008; 29(3):208-14. · 1.40 Impact Factor
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    Article: Bronchobiliary fistula detected with hepatobiliary scintigraphy.
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    ABSTRACT: Bile leakage into the thoracic cavity is a rare complication of invasive cancer. A 12-year-old boy was diagnosed with undifferentiated sarcoma of the right lobe of the liver invading the diaphragm. An extended right hepatectomy and total resection of the mass was performed, leaving a patchy tumoral invasion at the anterior diaphragmatic surface. Surgery was followed with a combined chemotherapy regimen. In the sixth postoperative month, he was readmitted with bilious expectoration. Tc-99m mebrofenin hepatobiliary scintigraphy revealed radiotracer accumulation in the right hemithorax. Bile leakage into the right thoracic cavity was diagnosed based on the hepatobiliary scintigraphic findings. For this patient; hepatobiliary scintigraphy, which is routinely used to visualize the liver and biliary tree, provided a noninvasive mean for the precise diagnosis of a bronchobiliary fistula. The fistula was then confirmed and corrected with surgery. The patient recovered uneventfully.
    Clinical Nuclear Medicine 05/2006; 31(4):237-9. · 3.67 Impact Factor
  • Article: Assessment of left ventricular function and volumes for patients with dilated cardiomyopathy using gated myocardial perfusion SPECT and comparison with echocardiography.
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    ABSTRACT: Left ventricular function, volumes and regional wall motion provide valuable diagnostic information and are of long-term prognostic importance in patients with dilated cardiomyopathy (DCM). This study was designed to compare the effectiveness of two-dimensional echocardiography and gated single photon emission computed tomography (SPECT) to evaluate these parameters in patients with DCM. Gated SPECT and two-dimensional echocardiography were performed in 45 patients with DCM, and in 10 normal subjects as the control group. Patients were divided into two groups according to the aetiology of DCM: group I, ischaemic DCM (n=30); group II, non-ischaemic DCM (n=15). All patients and the control group underwent resting myocardial gated SPECT, 45 min after injection of 555 MBq of Tc-methoxyisobutyl-isonitrile (Tc-MIBI). Gated SPECT data, including left ventricular volumes and left ventricular ejection fraction (LVEF), were processed using an automated algorithm. Simpson's method was used to evaluate these parameters. Regional wall motion was evaluated using both modalities and scored using a 16-segment model with a five-point scoring system. Perfusion defects were expressed as a percentage of the whole myocardium planimetered by a bull's-eye polar map of composite non-gated SPECT. Myocardial perfusion was scored using a 16-segment model with a four-point scoring system. Mean perfusion defects and perfusion defect scores were 25+/-13% and 1.12+/-0.36 in group I and 4+/-8% and 0.76+/-0.26 in group II (P<0.01). The overall agreement between the two imaging modalities for the assessment of regional wall motion was 57% (403/720 segments: 269/480 segments in group I and 134/240 segments in group II). With gated SPECT, LVEF was 27+/-9%, the end-diastolic volume (EDV) was 212+/-71 ml and the end-systolic volume (ESV) was 160+/-67 ml. With echocardiography, these values were 29+/-8%, 197+/-56 ml and 139+/-47 ml, respectively. The correlation between gated SPECT and two-dimensional echocardiography was good (r=0.72, P<0.01) for the assessment of LVEF. The correlation was also good for EDV and ESV, but with wider limits of agreement (r= 0.71, P<0.01 and r=0.71, P<0.01, respectively) and with significantly higher values with gated SPECT (P<0.01). For patients with a perfusion defect of <20% or low myocardial perfusion scores, a higher correlation was found between the two methods for the assessment of LVEF, EDV and ESV. On the other hand, the correlation was lower for the assessment of wall motion. Gated SPECT and two-dimensional echocardiography correlate well for the assessment of left ventricular function and volumes. Gated SPECT has the advantage of providing information about left ventricular function, dimensions and perfusion.
    Nuclear Medicine Communications 08/2005; 26(8):701-10. · 1.40 Impact Factor
  • Article: Clinical validation of technetium-99m MIBI-gated single-photon emission computed tomography (SPECT) for avoiding false positive results in patients with left bundle-branch block: comparison with stress-rest nongated SPECT.
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    ABSTRACT: Septal perfusion defects are common on myocardial perfusion single-photon emission computed tomography (SPECT) slices in patients with left bundle-branch block (LBBB) in the absence of coronary artery disease. The use of gated myocardial perfusion SPECT imaging in such patients should be clinically validated. The aims of this study were, therefore, to validate clinically the use of gated myocardial SPECT imaging to avoid false positive septal perfusion defects in patients with LBBB and to compare nongated and gated SPECT imaging techniques in the same patients in the same imaging session. We performed stress-rest myocardial perfusion SPECT and resting gated SPECT using Technetium-99m MIBI in 25 patients with LBBB and in 6 control subjects. Stress-rest SPECT images and end-diastolic and end-systolic gated SPECT slices were assessed visually and quantitatively (septum/lateral wall count ratio). Coronary angiography was performed in 15 patients with LBBB and in all 6 control subjects. Stress-rest (nongated) SPECT slices and end-diastolic and end-systolic gated SPECT images were normal in all control subjects. Stress-rest (nongated) SPECT imaging revealed septal perfusion defect in 20 (11 reversible, 9 irreversible) patients with LBBB, whereas the figures were 15 and 5 for end-systolic and end-diastolic gated SPECT images, respectively. Coronary angiography results were normal in all control subjects and in 15 patients with LBBB. Quantitative analysis of gated SPECT images revealed no statistically significant difference between patients with LBBB and control subjects in end-diastolic mean septum/lateral wall count values (0.86 +/- 0.19 in LBBB vs. 0.98 +/- 0.15 in normal subjects, p > 0.05), but the difference was statistically significant for end-systolic, stress, and rest values (p < 0.001 for all). Gated SPECT imaging, particularly end-diastolic images, revealed fewer false positive results and thus can be used to avoid false positive septal perfusion defects commonly seen in stress-rest (nongated) myocardial perfusion SPECT in patients with LBBB.
    Clinical Cardiology 04/2003; 26(4):182-7. · 2.15 Impact Factor
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    Article: Subhyoid ectopic thyroid with mediolateral location in a developmentally retarded child with hypothyroidism in an iodine deficiency region.
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    ABSTRACT: The authors present a case of subhyoid ectopic thyroid with mediolateral location diagnosed by technetium-99m pertechnetate scan. The ectopia was associated with hypothyroidism and developmental retardation.
    Annals of Nuclear Medicine 12/2002; 16(7):483-6. · 1.50 Impact Factor

Institutions

  • 2002–2012
    • Kocaeli University
      • Department of Nuclear Medicine
      Kocaali, Sakarya, Turkey
    • Ankara Numune Training and Research Hospital
      Ankara, Ankara, Turkey
  • 2011
    • Cumhuriyet University
      Sivas, Sivas, Turkey
  • 2009–2011
    • Gazi University
      • Faculty of Dentistry
      Ankara, Ankara, Turkey
  • 2003
    • Ankara University
      • Department of Nuclear Medicine
      Ankara, Ankara, Turkey