A Fuat Yapar

Baskent University, Engüri, Ankara, Turkey

Are you A Fuat Yapar?

Claim your profile

Publications (45)79.63 Total impact

  • Gül Nihal Nursal, Ali Fuat Yapar
    [Show abstract] [Hide abstract]
    ABSTRACT: We report a case of a 37-year-old woman with severe headache that is provoked by postural changes who was referred to the nuclear medicine department for radionuclide cisternography to demonstrate suspected cerebrospinal fluid leakage. There was an increased uptake laterally on the left paraspinal region of upper thoracal spine and posteriorly on the upper cervical region. Fused SPECT/CT images located the exact leakage site as at the first costovertebral junction level on the left side laterally and on the posterior region of the first and second cervical spine. The treatment with epidural blood patch was successful.
    Clinical Nuclear Medicine 07/2014; · 2.86 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Simultaneous occurence of medullary thyroid carcinoma (MTC) and papillary thyroid carcinoma (PTC) in a single patient is an unusual event. The incidence, cell origin, histopathology features and prognosis of these two carcinomas are considered completely different. The aim of this retrospective study was to describe clinical, pathologic characteristics and the prevalence of diagnosing such patients in our clinic. Between October 2003 and December 2013, 1.420 consecutive patients diagnosed by histology as having differentiated thyroid carcinoma (DTC) and treated with radioactive iodide (RAI) were retrospectively investigated. Of these, 4 patients were diagnosed by histology as having simultaneous MTC and PTC. The clinical and pathology characteristics of these patients are described. The prevalence of simultaneous MTC and PTC of these 4 patients in our clinic was 0.28% of all patients with DTC. The age of the 4 patients ranged from 44 to 63 years and were three females and one male. These patients are currently alive without disease from either of the two types of cancer. In two of these patients, MTC was located in the left and PTC in the right thyroid lobe. One patient had MTC in the right lobe and PTC in both lobes. The remaining patient had both cancers in the left lobe as a mixed tumor. We are able to present the pathology of only 2 of these 4 patients. In these 2 patients MTC was located in the left and PTC in the right thyroid lobe, one of them was female and the other was male, aged 44 and 49, respectively. In conclusion, our results suggested that simultaneous occurrence of MTC and PTC had a prevalence in our clinic of 0.28% among 1420 consecutive patients with DTC or 0.14%, if only the 2 patients in whom we are able to present their pathology slides are considered. Our cases suggest that these two tumors are usually independent and coincidental events in every patient.
    Hellenic journal of nuclear medicine 07/2014; · 0.93 Impact Factor
  • Source
    Cem Onal, Mehmet Reyhan, Ozan C Guler, Ali Fuat Yapar
    [Show abstract] [Hide abstract]
    ABSTRACT: We sought to evaluate failure patterns and prognostic factors predictive of recurrences and survival in cervical cancer patients who are treated with definitive chemoradiotherapy (ChRT), who have a subsequent complete metabolic response (CMR) with (18) F-fluorodeoxyglucose positron-emission tomography (FDG-PET) after treatment. The records of 152 cervical cancer patients who were treated with definitive chemoradiotherapy were evaluated. All patients underwent pre-treatment positron emission tomography (PET-CT), and post-treatment PET-CT was performed within a median of 3.9 months (range, 3.0-9.8 months) after the completion of ChRT. The prognoses of partial response/progressive disease (PR/PD) cases (30 patients, 18 %) and CMR cases (122 patients, %82) were evaluated. Univariate and multivariate analysis effecting the treatment outcome was performed in CMR cases. The median follow-ups for all patients and surviving patients were 28.7 (range, 3.3-78.7 months) and 33.2 months (range, 6.23-78.7 months), respectively. Four-year overall survival (OS) rate was significantly better in patients with CMR compared to patients with PR/PD (66.9 % vs. 12.4 %, p < 0.001, respectively). Patients with PR/PD had higher maximum standardized uptake value (SUVmax) of primary cervical tumor (26.4 ± 10.1 vs. 15.9 ± 6.3; p < 0.001) and larger tumor (6.4 cm ± 2.3 cm vs. 5.0 cm ± 1.4 cm; p < 0.001) compared to patients with CMR. Of the 122 patients with post-treatment CMRs, 25 (21 %) developed local, locoregional, or distant failure. In univariate analysis, tumor size ≥ 5 cm, 'International Federation of Obstetricians and Gynecologists' (FIGO) stage ≥ IIB, and pelvic and/or para-aortic lymph node metastasis were predictive of both overall survival (OS) and disease-free survival (DFS), while histology was predictive of only OS. In multivariate analysis, tumor size, stage and lymph node metastasis were predictive of OS and DFS. Although CMR is associated with better outcomes, relapses remain problematic, especially in patients with bulky tumors (≥ 5 cm), extensive stage (≥ IIB) or pelvic and/or para-aortic lymph node metastasis. These findings could support the need for more aggressive treatment or adjuvant chemotherapy regimens.
    European Journal of Nuclear Medicine 02/2014; · 4.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Metastatic insulinomas may sometimes present with recurrent life-threatening hypoglycemia episodes. Such patients usually fail to respond to various therapeutic agents which causes constant dextrose infusion requirement. Herein, we present a resistant case of inoperable malignant insulinoma who was treated with many therapeutic agents and interventions including somatostatin analogues, Yttrium-90 radioembolization, everolimus, radiotherapy, and chemoembolization. Close blood sugar monitorization during these therapies showed the most favourable response with everolimus. Everolimus treatment resulted in rapid improvement of hypoglycemia episodes, letting us discontinue dextrose infusion and discharge the patient. However, experience with everolimus in such patients is still limited, and more precise data can be obtained with the increasing use of this agent for neuroendocrine tumours.
    Case reports in endocrinology. 01/2013; 2013:636175.
  • Source
    Erkan Topkan, Cem Parlak, Ali Fuat Yapar
    [Show abstract] [Hide abstract]
    ABSTRACT: The impact of [(18)F]fluorodeoxyglucose-positron emission tomography (PET)/computed tomography (CT) restaging on management decisions and outcomes in patients with locally advanced pancreatic carcinoma (LAPC) scheduled for concurrent chemoradiotherapy (CRT) is examined. Seventy-one consecutive patients with conventionally staged LAPC were restaged with PET/CT before CRT, and were categorized into non-metastatic (M0) and metastatic (M1) groups. M0 patients received 50.4 Gy CRT with 5-fluorouracil followed by maintenance gemcitabine, whereas M1 patients received chemotherapy immediately or after palliative radiotherapy. In 19 patients (26.8%), PET/CT restaging showed distant metastases not detected by conventional staging. PET/CT restaging of M0 patients showed additional regional lymph nodes in 3 patients and tumors larger than CT-defined borders in 4. PET/CT therefore altered or revised initial management decisions in 26 (36.6%) patients. At median follow-up times of 11.3, 14.5, and 6.2 months for the entire cohort and the M0 and M1 cohorts, respectively, median overall survival was 16.1, 11.4, and 6.2 months, respectively; median locoregional progression-free survival was 9.9, 7.8, and 3.4 months, respectively; and median progression-free survival was 7.4, 5.1, and 2.5 months, respectively (P < 0.05 each). These findings suggest that PET/CT-based restaging may help select patients suitable for CRT, sparing those with metastases from futile radical protocols, and increasing the accuracy of estimated survival.
    Cancer Imaging 01/2013; 13(3):423-8. · 1.29 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: The aim of this study was to compare computed tomography (CT)- and positron emission tomography (PET)/CT-based gross tumor volume (GTV) delineation and its subsequent expansion to the planning target volume (PTV), and to analyze the resultant doses of 3-dimensional conformal radiotherapy (3D-CRT) to critical organs. Methods: 15 patients with unresectable extrahepatic cholangiocarcinoma (EHCC) were enrolled into this study. PTVCT-based plans were initially made, and then PTVPET-CT-based plans were created using the same beam angles and isocenter. The dosimetric parameters analyzed included GTVCT, PTVCT, GTVPET-CT and PTVPET-CT. Prescribed and delivered radiation doses to target volumes and delineated organs at risk were also compared. Results: Mean GTV and PTV were significantly reduced in the PET/CT-based plan compared to the CT-based plan; the mean reductions of GTV and PTV were 28.7% and 15.2%, respectively. The mean value for GTVPET/GTVCT mismatch was 49.5 ± 28.9%, and that for GTVCT/GTVPET was 95.9 ± 19.5%. The mean value for PTVPET-CT/PTVCT mismatch was 21.9 ± 7.0% and that for PTVCT/PTVPET-CT was 39.1 ± 9.2%. Liver doses were significantly reduced (17.1%) in the PET/CT-based plan compared to the CT-based plan; the doses received by at least 30% and 50% of the liver were 30.0%, and 27.3%, respectively. Conclusion: The potential benefit of PET/CT is the reduction in geographic misses and regional treatment failures associated with CT-based planning. © 2013 S. Karger GmbH, Freiburg.
    Onkologie 01/2013; 36(9):484-90. · 0.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: PURPOSE : We investigated the usability of standardized uptake values (SUV) obtained from both two- and three-dimensional (2D and 3D) positron-emission tomography and computed tomography (PET-CT) imaging, and compared the images obtained from these techniques in terms of image quality, lesion detectability, and the presence of artifacts. MATERIALS AND METHODS: Image data from 100 patients, who had undergone two PET imagings obtained in 2D and 3D mode after a low dose CT, were evaluated prospectively. Subjective analysis of 2D and 3D images was performed by two readers evaluating the following criteria: overall image quality, detectability of each identified lesion, and the presence of artifacts. The lesions recognized by the readers were also analyzed quantitatively by measuring SUV values. RESULTS : There was a significant difference between the SUVs obtained in 2D and 3D modes. Regardless if the first scan was performed in 2D or 3D mode, the values obtained from 3D imaging were significantly lower than those obtained from 2D imaging (mean SUV max was 10.48±7.57 for 2D, and 9.66±6.93 for 3D, P = < 0.001). Visual analysis did not reveal significant differences regarding lesion detectability between two modes. max CONCLUSION: In oncological PET-CT applications, SUV values are significantly lower in 3D compared with 2D mode. Thus when serial scanning is needed to evaluate response to therapy in the same patient, the imaging modality should be taken into account and performed with the same method to avoid mis- interpretation. Additionally, 3D PET-CT imaging can be used instead of 2D PET-CT due to its shorter scanning time without loss of lesion detectability.
    Diagnostic and interventional radiology (Ankara, Turkey) 12/2012; · 1.03 Impact Factor
  • A F Yapar
    Revista española de medicina nuclear e imagen molecular. 11/2012; 31(6):357-8.
  • Ali Fuat Yapar, Mehmet Reyhan
    [Show abstract] [Hide abstract]
    ABSTRACT: A 38-year-old man presented with declining appetite and progressive abdominal distention. Abdominal ultrasonography revealed omental and bowel wall thickening. Histopathologic examination showed a high-grade lymphoblastic Burkitt-like B-cell lymphoma. 18F fluorodeoxyglucose positron emission tomography/computed tomography images showed diffusely increased metabolic activity in the thickened omentum, intestines, mesentery, and peritoneum (omental caking). Diffuse peritoneal and omental seeding are well-known forms of dissemination of metastatic carcinoma. However, omental and peritoneal lymphomatosis are rare manifestations of high-grade lymphomas. This uncommon case demonstrates usefulness of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in omental and peritoneal involvement in lymphoma.
    Clinical nuclear medicine 07/2012; 37(7):e176-7. · 3.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Assessment of carbohydrate antigen (CA) 19-9 levels is used for diagnosis and follow-up of pancreaticobiliary cancers, and high levels of this biomarker are suggestive of a malignancy. CA 19-9 may also be elevated in patients with conditions other than tumors, such as cholestasis, biliary obstruction, and cholecystitis. Case Report: A 50-year-old male patient presented with jaundice and elevated CA 19-9 levels (161,902 IU/ml). Repeated biopsies of the common bile duct revealed no malignancies. Radiological findings indicated a mass protruding through the common bile duct. Positron emission tomography demonstrated increased (18)F-fluoro2-deoxy-D-glucose uptake in the liver and a mass resembling metastasis was detected. A Whipple procedure was performed and demonstrated no tumor. Postoperatively, CA 19-9 levels decreased to within normal limits (27 IU/ml). Conclusion: These results indicate that CA 19-9 levels should not be the sole criterion for a diagnosis of malignancy. Although other analytical tools may aid diagnosis, surgical exploration may be required in some instances to avoid misdiagnosis and determine whether radiological results are falsely positive.
    Onkologie 01/2012; 35(12):780-2. · 0.84 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We aimed to study the predictive value of combined 18F-fluoro-deoxy-D-glucose positron emission tomography and computerized tomography (FDG-PET-CT), on outcomes in locally advanced pancreatic carcinoma (LAPC) patients treated with concurrent chemoradiotherapy (C-CRT). Thirty-two unresectable LAPC patients received 50.4 Gy (1.8 Gy/fr) of RT and concurrent 5-FU followed by 4 to 6 cycles of gemcitabine consolidation. Response was evaluated by FDG-PET-CT at post-C-CRT 12-week. Patients were stratified into two groups according to the median difference between pre- and post-treatment maximum standard uptake values (SUVmax) as an indicator of response for comparative analysis. At a median follow-up of 16.1 months, 16 (50.0%) patients experienced local/regional failures, 6 of which were detected on the first follow-up FDG-PET-CT. There were no marginal or isolated regional failures. Median pre- and post-treatment SUVmax and median difference were 14.5, 3.9, and -63.7%, respectively. Median overall survival (OS), progression-free survival (PFS), and local-regional progression-free survival (LRPFS) were 14.5, 7.3, and 10.3 months, respectively. Median OS, PFS, and LRPFS for those with greater (N = 16) versus lesser (N = 16) SUVmax change were 17.0 versus 9.8 (p = 0.001), 8.4 versus 3.8 (p = 0.005), and 12.3 versus 6.9 months (p = 0.02), respectively. On multivariate analysis, SUVmax difference was predictive of OS, PFS, and LRPFS, independent of existing covariates. Significantly higher OS, PFS, and LRPFS in patients with greater SUVmax difference suggest that FDG-PET-CT-based metabolic response assessment is an independent predictor of clinical outcomes in LAPC patients treated with definitive C-CRT.
    BMC Gastroenterology 11/2011; 11:123. · 2.11 Impact Factor
  • Clinical nuclear medicine 11/2011; 36(11):1041-3. · 3.92 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate longitudinal function of ischemic and nonischemic myocardial tissue detected by Tc-99m MIBI single photon emission computed tomography (SPECT) prior to coronary revascularization in patients with stable angina pectoris. We studied 24 consecutive patients (mean age 62+/-9 years; 5 women) with stable angina pectoris. All patients underwent myocardial perfusion SPECT. Tissue Doppler imaging (TDI) was performed to detect myocardial systolic velocities of anterior, inferior, septum and lateral walls at rest and peak dobutamine stress. A total of 96 segments were visualized with SPECT study. Maximum mean septal, lateral, anterior and inferior TDI systolic velocities were similar in ischemic and nonischemic segments (6.73+/-1.04 cm/sec, 6.93+/-1.34 cm/sec, respectively) at rest. At peak stress, maximum mean TDI systolic velocities were lower in the 37 ischemic segments (11.00+/-2.03 cm/sec) than 59 nonischemic segments (13.76+/-1.97 cm/sec, p = 0.001). Because we detected ischemia in whole group using both diagnostic tests, coronary angiography was decided. Critical coronary artery stenosis related to ischemic segments was detected and coronary revascularization decided. TDI with dobutamine stress can be used in patients with stable angina pectoris. In this study, we observed that quantitative data by TDI associated with SPECT showed an agreement for coronary revascularization.
    Anadolu kardiyoloji dergisi: AKD = the Anatolian journal of cardiology 08/2010; 10(4):334-9. · 0.72 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Positron emission tomography (PET) has the potential to improve staging and radiation treatment-planning (RTP) for tumors in various sites. We compared computed tomography (CT) with co-registered 18F-fluorodeoxyglucose (FDG)-PET-CT) as the basis for delineating gross tumor volume (GTV) in patients with rectal carcinoma undergoing preoperative three-dimen- sional conformal radiotherapy (3D-CRT). Twenty-three patients diagnosed with localized rectal carcinoma who were candidates for preoperative chemoradiation were evaluated using both CT and PET imaging. For each patient, two 3D-CRT plans were created using the CT and PET-CT fusion data sets. GTV was contoured on both CT (GTVCT) and co-registered PET-CT (GTVPET-CT) images. The resulting GTVCT and GTVPET-CT images were analyzed comparatively. The median GTVPET-CT (40 cm3) was significantly greater than the median GTVCT (25.7 cm3) (p= 0.0001). The median dif- ference between GTVPET-CT and GTVCT was 65%. The intersected tumor volume determined by the two methods was median 19.7 cm3, and tumor volumes remaining outside CT was median 15.2 cm3. The median volume identified by PET but not by CT (PEToutCT) was 35% of GTVPET-CT, indicating the possibility of a geographic miss in GTV. Co-registration of PET and CT information in localized rectal cancer may improve the delineation of GTV and theoretically reduce the likelihood of geographic misses, thus potentially having a positive impact on treatment planning.
    UHOD - Uluslararasi Hematoloji-Onkoloji Dergisi 01/2010; 20(2):67-74. · 0.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The management of the patients with carcinoma of an unknown primary represents a difficult challenge in oncology. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has provided new insights in the diagnosis, staging, and follow-up of oncological patients. This study aimed to investigate the value of FDG PET/CT in clarifying the primary site in our patients with histologically proven tumor metastasis (HPM) or with a high clinical suspicion of malignancy, and the clinical impact of this technique on the management of these patients. In total 94 patients from two centers underwent FDG PET/CT imaging; 78 patients with HPM and 16 patients with a clinical suspicion of malignancy. The histology and/or follow-up data were used as the gold standard. Hypermetabolic findings at the site of the pathological CT changes or at physiological FDG uptake sites were the criteria for malignancy. PET/CT findings were analyzed for the identification of the primary tumor site, for the relationship with survival, and also for the effect in chemotherapy monitoring. Primary malignancy was discovered in 53 of 90 patients (59%) histologically and 37 (41%) patients' primary tumor sites were not found during the study period. Amongst 90 patients, five (6%) were normal on FDG PET/CT. Of 85 patients (94%) with pathological findings on FDG PET/CT, 27 patients (32%) had solitary and 58 (68%) patients had multiple organs affected. Regarding the whole study population, a sensitivity of 74% and a specificity of 78% were calculated for FDG PET/CT imaging. Regarding the patients with HPM, the sensitivity and specificity values were 84 and 81%, respectively. The mean survival time of the patients with disseminated disease was significantly shorter than those of the patients with single or no lesion (13.44+/-1.61, 20.98+/-2.0 and 26.67+/-2.73 months, respectively, P=0.014). In seven of eight patients, follow-up FDG PET/CT scans effectively monitored the patients' therapies. Whole-body FDG PET/CT has to be considered a useful method, especially in an early phase of the diagnostic workup of patients with carcinoma of an unknown primary syndrome, to optimize the management.
    Nuclear Medicine Communications 01/2010; 31(1):59-66. · 1.37 Impact Factor
  • Ali Fuat Yapar, Mehmet Reyhan, E Tuba Canpolat
    [Show abstract] [Hide abstract]
    ABSTRACT: Fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) has been increasingly used for differentiating between benign and malignant pulmonary nodules or masses. Glucose utilization by malignant tissues is generally higher, resulting in higher FDG uptake and SUVs on PET images than in benign tissues. However, some benign pathologies with infection/inflammation may mimic the appearance of malignant lesions on FDG PET/CT. Amebiasis is the third leading cause of death due to parasitic infections worldwide. Although, intestinal disease is the most common manifestation of amebiasis, migration to the liver and lung may occur. This case highlights a primary pulmonary ameboma showing increased metabolism, and suggested lung cancer.
    Clinical nuclear medicine 01/2010; 35(1):55-6. · 3.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pozitron emisyon tomografisi (PET) birçok tümörün evrelenmesi ve radyoterapi planlamasında potansiyel bir kazanç sağlamıştır. Rektum kanserinin preoperatif konformal radyoterapisi öncesi bilgisayarlı tomografi (BT) ile 18F-fluorodeoksiglikoz positron emisyon tomografi/bilgisayalı tomografi (FDG-PET/BT) bazlı 3-boyutlu tedavi planlamaları karşılaştırılmıştır. Kliniğimizde rektum kanseri tanısı ile preoperatif kemoradyoterapi planlanan 23 hasta çalışmaya alınmıştır. Tüm hastaların tedavi öncesinde, tedavi pozisyonunda olacak şekilde PET ve BT görüntüleri elde edilmiştir. Her hastanın gros tümör volümü (GTV) önce BT (GTVCT), sonra PET/BT (GTVPET-CT) görüntülerinde konturlanmış; GTVCT ve GTVPET-CT değerleri ölçülmüştür. Ortanca GTVPET-CT (40 cm3), GTVCT (25.7 cm3)’den daha büyük olarak belirlenmiş ve aradaki fark istatistiksel olarak anlamlı bulunmuştur (p = 0.0001). GTVPET-CT ve GTVCT arasındaki fark %65’ dir. Her iki yöntemle kesişen ortanca tümör volümü 19.7 cm3 ve BT dışı ortanca tümör volümü 15.2 cm3 olarak ölçülmüştür. BT dışı ortanca tümör volümü GTVPET-CT’nin %35’i olup tümörün coğrafik hata ile kaçırılabileceğini göstermektedir. Bu sonuçlar rektum kanserinin preoperatif konformal radyoterapi planlamasında PET/BT kullanımının hedef volümün daha doğru belirlenebilmesi ve coğrafik hatanın minimuma indirilmesinde önemli olduğunu düşündürmektedir.
    International Journal of Hematology and Oncology. 01/2010; 20(2):67-74.
  • EJC Supplements 09/2009; 7(2):329-329. · 2.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to evaluate the efficacy of dual-phase 99mTc-methoxyisobutylnitrile (MIBI) parathyroid scintigraphy (PS) and ultrasound (US) in primary (pHPT) and secondary (sHPT) hyperparathyroidism. A total of 69 patients (mean age 47+/-16; age range 14-79 years), including 19 patients with sHPT were enrolled in this study. Preoperative serum intact parathyroid hormone (iPTH) levels, calcium (Ca), phosphate (P), alkaline phosphatase, and 24-h urinary-free Ca measurements were obtained. Concomitant thyroid pathology was also recorded. Histopathology revealed 30 solitary adenomas and 71 hyperplastic glands in 55 patients. The remaining patients' histopathology revealed normal parathyroid, thyroid, or lymph nodes. The sensitivities of MIBI and US in pHPT were 70% and 60%, respectively. It was 60% for both procedures in sHPT. The overall sensitivity of combined US + MIBI in pHPT and sHPT was 81% and 71%, respectively. The overall specificity of MIBI and US was 87% and 91%; positive predictive value (PPV) was 94% and 92%, respectively. MIBI and US identified the parathyroid pathology in 92% and 85% of patients in the non-concomitant thyroid disease group, and in 53% and 47% of patients in the concomitancy thyroid disease group, respectively. The weight of the gland between primary and secondary hyperparathyroidism did not reveal a significant difference (P=0.4). Significant differences were found with respect to age, PTH, Ca, and P levels between the pHPT and sHPT (P<0.001). Intact PTH levels showed significant differences between MIBI positive and negative patients (P=0.013), and also US positive and negative patients (P=0.012). A significant negative correlation was found between iPTH and Ca at sHPT (P<0.001). The concomitant of thyroid disease greatly influences scintigraphic and ultrasonographic detection of parathyroid pathology in pHPT and sHPT. The combination of MIBI and US appears promising for localizing parathyroid pathology in patients with both primary and secondary hyperparathyroidism. The concordance rate is high together with a lower chance of missing concomitant thyroid pathology, which might alter the surgical approach.
    Annals of Nuclear Medicine 02/2008; 22(2):123-31. · 1.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to evaluate the use of 99mTc(V)-dimercaptosuccinic acid (99mTc(V)-DMSA) scintigraphy for the assessment of disease activity in patients with Graves' ophthalmopathy (GO) and compare their clinical parameters. The study involved 20 patients who were clinically inactive and eight patients who were clinically active, a total 28 GO patients (18 female, 10 male; mean age: 39.2+/-13.4 years) and 12 control subjects (six female, six male; mean age: 57.12+/-12 years). Planar and SPECT orbital images were obtained 4 h after the intravenous injection of 555-740 MBq 99mTc(V)-DMSA, using low-energy, high-resolution, parallel-hole collimators with dual-head detectors. All SPECT data were reconstructed on conventional axial, sagittal and coronal projections using an iterative reconstruction. Semi-quantitative evaluation was performed comparing the orbital activity with nasal activity based on four grades. GO was classified according to the NOSPECS classification of the American Thyroid Association. Disease was considered clinically active if symptoms and signs deteriorated over 3 months. No significant correlation was detected between clinical activity and classification (P=0.192). However, clinical activity and 99mTc(V)-DMSA uptake were significantly correlated (P=0.0001). There was no correlation between the clinical classification and scintigraphic grading. Bilateral orbital index of the active group was significantly higher than that of the inactive group (P=0.0001). 99mTc(V)-DMSA imaging discriminates the active from inactive GO as well as showing an ongoing subclinical inflammation in the orbits of the patients with GO, regardless of the disease activity clinically. Our results revealed that 99mTc(V)-DMSA is a promising agent for the diagnosis of active Graves' ophthalmopathy.
    Nuclear Medicine Communications 11/2007; 28(10):775-81. · 1.37 Impact Factor

Publication Stats

226 Citations
79.63 Total Impact Points


  • 2005–2013
    • Baskent University
      • Department of Nuclear Medicine
      Engüri, Ankara, Turkey
  • 2009
    • Saitama Medical University
      Saitama, Saitama, Japan
  • 2004
    • Baskent Üniversitesi Adana Uygulama ve Arastirma Merkezi
      Adhanah, Adana, Turkey