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Dive into the research topics where Ahmet Candan Durak is active.

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Featured researches published by Ahmet Candan Durak.


European Journal of Radiology | 2011

Comparison of 16-row multislice CT angiography with conventional angiography for detection and evaluation of intracranial aneurysms

Halil Donmez; Elman Serifov; Guven Kahriman; Ertugrul Mavili; Ahmet Candan Durak; Ahmet Menkü

PURPOSE The aim of this study is to compare the diagnostic performance of 16-row computed tomographic angiography (MDCTA) with digital subtraction angiography (DSA) for the detection and characterization of intracranial aneurysms in patients with nontraumatic subarachnoid hemorrhages (SAH). MATERIALS AND METHODS One-hundred and twelve consecutive patients with suspected intracranial aneurysm underwent both 16-row MDCTA and DSA. The MDCT angiograms were interpreted in a blinded fashion by using combination with VRI, MIP and MPR techniques. Sensitivity specificity and accuracy were calculated for the CTA and DSA. The results were compared with each other. The DSA readers interpretation was accepted as the reference standard. RESULTS A total of 164 aneurysms were detected at DSA in 112 patients, no aneurysms were detected by DSA and MDCTA in 16 patients. Eight aneurysms were missed by MDCTA. The overall sensitivity, specificity, and accuracy of MDCTA on a per-aneurysm basis were 95.1%, 94.1%, and 95%, respectively. According to the size of the aneurysm less than 3mm; sensitivity, specificity and diagnostic accuracy of MDCTA were 86.1%, 94.1%, 88.6%, respectively. CONCLUSION This study suggests that MDCTA is equally as sensitive as DSA in the detection of intracranial aneurysms of greater than 3mm, and it also reveals 100% detection rate for ruptured aneurysms.


BMC Infectious Diseases | 2006

Doxycycline plus streptomycin versus ciprofloxacin plus rifampicin in spinal brucellosis [ISRCTN31053647]

Emine Alp; Rahmi Kemal Koc; Ahmet Candan Durak; Orhan Yildiz; Bilgehan Aygen; Bulent Sumerkan; Mehmet Doganay

BackgroundThe optimal treatment regimen and duration of the therapy is still controversial in spinal brucellosis. The aim of this study is to compare the efficacy, adverse drug reactions, complications and cost of ciprofloxacin plus rifampicin versus doxycycline plus streptomycin in the treatment of spinal brucellosis.MethodsThe patients diagnosed as spinal brucellosis between January 2002 to December 2004 were enrolled into the study. Patients were enrolled into the two antimicrobial therapy groups (doxycycline plus streptomycin vs. ciprofloxacin plus rifampicin) consecutively. For the cost analysis of the two regimens, only the cost of antibiotic therapy was analysed for each patient.ResultsDuring the study period, 31 patients with spinal brucellosis were enrolled into the two antimicrobial therapy groups. Fifteen patients were included in doxycycline plus streptomycin group and 16 patients were included in ciprofloxacin plus rifampicin group. Forty-two levels of spinal column were involved in 31 patients. The most common affected site was lumbar spine (n = 32, 76%) and involvement level was not different in two groups. Despite the disadvantages (older age, more prevalent operation and abscess formation before the therapy) of the patients in the ciprofloxacin plus rifampicin group, the duration of the therapy (median 12 weeks in both groups) and clinical response were not different from the doxycycline plus streptomycin. The cost of ciprofloxacin plus rifampicin therapy was 1.2 fold higher than the cost of doxycycline plus streptomycin therapy.ConclusionClassical regimen (doxycycline plus streptomycin), with the appropriate duration (at least 12 weeks), is still the first line antibiotics and alternative therapies should be considered when adverse drug reactions were observed.


Thyroid | 2003

Hydatic Cyst in the Thyroid Gland Diagnosed by Fine-Needle Aspiration Biopsy

Cumali Gökçe; Tahir Patiroglu; Seyfi Akşehirli; Ahmet Candan Durak; Fahrettin Kelestimur

A 33-year-old man was admitted with a swelling in the right lobe of the thyroid gland of 1 years duration. Laboratory investigations and thyroid function tests were normal. Thyroid scanning showed a cold nodule in the lower pole of the right thyroid lobe. Thyroid ultrasonography showed multiple cystic nodules in the thyroid gland. To make a differential diagnosis of the thyroid nodule, fine-needle aspiration biopsy (FNAB) was performed and hydatic cyst of the thyroid gland was diagnosed. Subtotal thyroidectomy was carried out and histopathologic examination confirmed the diagnosis. During aspiration biopsy, the patient did not present a clinical picture of anaphylactic reaction. To our knowledge, this is the first case of thyroid hydatic cyst diagnosed by FNAB reported in the literature.


European Journal of Endocrinology | 2014

EXTENSIVE INVESTIGATION OF 114 PATIENTS WITH SHEEHAN'S SYNDROME: A CONTINUING DISORDER

Halit Diri; Fatih Tanriverdi; Zuleyha Karaca; Serkan Senol; Kursad Unluhizarci; Ahmet Candan Durak; Hulusi Atmaca; Fahrettin Kelestimur

OBJECTIVE Sheehans syndrome (SS) is a well-known cause of hypopituitarism resulting from postpartum pituitary necrosis. Because of its rarity in Western society, its diagnosis is often overlooked. We aimed to investigate the clinical, laboratory, and radiological aspects of SS in a large number of patients. STUDY DESIGN A retrospective assessment of the medical records of 114 patients with SS was conducted. In addition, sella turcica volumes of 29 healthy women were compared with those of patients by magnetic resonance imaging examinations. RESULTS The mean period of diagnostic delay was 19.7 years in patients with SS. It was found that 52.6% of patients had nonspecific complaints, 30.7% had complaints related to adrenal insufficiency, and 9.6% had complaints related to hypogonadism when diagnosed. At the time of diagnosis, 55.3% of the patients had panhypopituitarism, while 44.7% had partial hypopituitarism. The number of deficient hormones was found to be increased over the years. None of the patients whose basal prolactin was below 4.0 ng/ml had adequate prolactin responses to TRH test, while all patients whose basal prolactin was above 7.8 ng/ml had adequate responses. Mean sella volume was found to be significantly lower in the SS group (340.5±214 mm(3)) than that in the healthy group (602.5±192 mm(3)). CONCLUSIONS SS is a common cause of hypopituitarism in underdeveloped and developing countries. The main reasons for diagnostic delay seem to be the high frequency of patients with nonspecific complaints and neglect of SS. In addition, the TRH stimulation test was found to have a high sensitivity and specificity to recognize PRL deficiency. Furthermore, small sella size may have an important contributing role in the etiopathogenesis of SS.


CardioVascular and Interventional Radiology | 2009

Stroke Secondary to Aseptic Meningitis After Endovascular Treatment of a Giant Aneurysm with Parent Artery Occlusion

Halil Donmez; Ertugrul Mavili; Türkan İkizceli; Ahmet Candan Durak; Ali Kurtsoy

Aseptic meningitis related to hydrogel-coated coils is a known complication, but it is extremely rare after platinum bare coil aseptic meningitis. Here we report the development of aseptic meningitis causing brain stem and cerebellar infarct in a patient with a giant aneurysm treated with bare platinum coils. We conclude that aneurysm size is an important factor affecting the occurrence of aseptic meningitis associated with stroke.


Rivista Di Neuroradiologia | 2008

The Role of Diffusion-Weighted Magnetic Resonance Imaging in Intracranial Cystic Lesions

A. Yikilmaz; Ahmet Candan Durak; Ertugrul Mavili; H. Donmez; A. Kurtsoy; O. Kontas

We aimed to define the diffusion-weighted magnetic resonance (MR) imaging features of intracranial cystic lesions and to investigate possible special features for the differential diagnosis. One hundred and twenty patients with intracranial cystic lesions were included in the study. There were 29 arachnoid cysts, eight epidermoid cysts, 34 primary tumors, 18 abscesses, 29 metastases and two hydatid cysts. Echo-planar diffusion-weighted MR imaging was obtained in addition to conventional cranial MR scans. The morphologic features of the cystic portion and the wall of the cyst and signal intensities on diffusion-weighted images were evaluated. All abscesses and epidermoid cysts were hyperintense on diffusion-weighted images. Arachnoid cysts, hydatid cysts, primary tumors, and metastases were hypointense except five cystic tumors. These five primary or metastatic necrotic tumors showed high signal intensity on diffusion-weighted images due to hemorrhage or superinfection. The walls of the cystic tumors were usually hyperintense on diffusion-weighted images in contrast to the wall of the abscesses, which were iso-hypointense. This was a statistically significant finding for the differentiation between tumors and abscesses (P<0.05). Diffusion-weighted MR imaging is a useful technique for the evaluation of the intracranial cystic lesions and provides additional beneficial information to conventional MR imaging. However, the presence of hemorrhage and superinfection of the tumors may cause a signal increase that results in misinterpretetations. In these cases, the appearance of tumor wall may be useful for differentiating abscesses from tumors.


Renal Failure | 2001

The hormonal and radiological evaluation of adrenal glands, and the determination of the usefulness of low dose ACTH test in patients with renal amyloidosis.

Selim Kurtoglu; Zübeyde Gündüz; Fahrettin Kelestimur; Ahmet Candan Durak; Cengiz Utas; Mehmet Büyükberber; Ruhan Dusunsel; M. Hakan Poyrazoğlu

Amyloidosis is a multisystem disease which may cause organloss. Renal involvement is the most common clinical problem in amyloidosis,however involvement of endocrin organs is possible. In this study to assessadrenocortical function and to evaluate the usefulness of low dose ACTH testin patients with renal amyloidosis, we determined cortisol, 17-hydroxyprogesteron(17-OHP) and 11-deoxycortisol (11-DOC) responses to both 1 μg and 250 μgSynacthen. We also determined the size of adrenal glands radiologically byusing computerized tomography. Twenty one patients with renal amyloidosisand 16 healthy subjects for hormonal evaluation, and 20 patients with renalamyloidosis and 22 healthy subjects for radiologic evaluation were includedin the study. In four patients (19%) peak serum cortisol levels followingstimulation with the low dose of Synacthen were less than 20 μg/dL (550nmol/L). Two of them had also subnormal cortisol response to the 250 μgSynacthen stimulation test. Basal and stimulated levels of 11-DOC were lowerthan those of control values (p = 0.000and p < 0.01 respectively). The mean11-DOC responses to stimulation with 1 μg Synacthen were also significantlylower than the values obtained after the simulation with 250 μg Synacthen(p < 0.01 and p= 0.000). Cortisol responses to the stimulation with 250 μg Synacthen werealso lower than the control responses (p< 0.05). 17-OHP responses were similar to the control values in both tests.In the radiological evaluation the mean maximum width of right adrenal glandsand the mean anterior and maximum width of left adrenal glands were significantlygreater in the patient group (p < 0.01).In conclusion, adrenal involvement and adrenal insufficiency is common inamyloidosis. Low 11-DOC levels in amyloidosis is a new finding and furtherdetailed studies is required to explain its cause.


Turkish Neurosurgery | 2014

Prognostic factors obtained from long-term follow-up of pituitary adenomas and other sellar tumors.

Halit Diri; Ersin Ozaslan; Ali Kurtsoy; Bülent Tucer; Yasin Simsek; Figen Öztürk; Ahmet Candan Durak; Fahri Bayram

AIM Pituitary adenomas do not have a single factor of aggressive behavior or recurrence. The objective of this study was to determine factors influencing the prognosis in pituitary adenomas. MATERIAL AND METHODS 243 patients who were operated between January 2000 and June 2012 were included in this retrospective study. Demographic data, age at diagnosis, date of diagnosis, date of operation, type of operation, post-operative medications, pre- and postoperative hormone levels, and MRI findings were evaluated in each patient. RESULTS The rate of total resection of sellar tumors was less than 50% in our patient population. The prognosis was better in cases with total resection. Tumor size was a poor prognostic factor in sellar tumors. Female sex was a poor prognostic factor in acromegaly and male sex in prolactinoma. The prognosis was worse in patients with cavernous sinus invasion. In acromegaly, pre-operative level of 850 ng/ml for IGF-1 was noted as a possible prognostic cut-off value. CONCLUSION Long-term follow-up results of our study suggest that factors common to all sellar tumors including tumor type, tumor size, total resection, and cavernous sinus invasion and tumor type-specific factors including sex and hormone levels play important roles in the prognosis.


Turkish Neurosurgery | 2015

Evaluation of Aggressive Behavior and Invasive Features of Pituitary Adenomas Using Radiological, Surgical, Clinical and Histopathological Markers.

Ahmet Kucuk; Fahri Bayram; Figen Öztürk; Abdulfettah Tumturk; Halit Diri; Sukru Oral; Bülent Tucer; Ahmet Candan Durak; Ali Kurtsoy

AIM Total surgical resection of pituitary macroadenomas is difficult due to the location of the adenoma and the propensity to invade surrounding tissues. The purpose of this study was to evaluate the risk factors for invasive and aggressive pituitary macroadenomas using radiological, hormonal, clinical, and immunohistochemical markers. MATERIAL AND METHODS Seventy cases of pituitary macroadenoma were examined. Age, gender, symptoms, the presence of fibrosis within the adenoma, hormonal levels, radiological findings, pathological results and immunohistochemical staining of the patients were evaluated using statistical methods. RESULTS We observed that the patients with macroadenomas in our study most frequently presented during their 5th decade. The most frequent pituitary adenomas were non-functional, GH-secreting and PRL-secreting macroadenomas. The most frequent complaint was vision loss, headache and acral growth. Based on Magnetic Resonance Imaging (MRI) results, it was observed that the degree of invasion into surrounding tissues increased as the size of the macroadenoma increased. Macroadenomas that had invaded into the cavernous sinus invasion or that had a fibrotic tumor structure had a low probability of being resectable. There were no significant relationships between invasive behavior and p53, telomerase, ghrelin and CD46. CONCLUSION It is not possible to identify only one factor that affects the prognosis of patients with pituitary macroadenomas. The contribution of the experience of surgeon to the treatment is surely beyond dispute. Fibrotic tumor structure, the surgical technique, the type of hormone, and cavernous sinus invasion affect the ability to perform a total resection and the overall prognosis.


Turkish Neurosurgery | 2015

Is Positive Staining of Non-Functioning Pituitary Adenomas for Luteinizing Hormone Associated with a Poor Prognosis?

Halit Diri; Ersin Ozaslan; Ali Kurtsoy; Bülent Tucer; Yasin Simsek; Figen Öztürk; Ahmet Candan Durak; Erten S; Fahri Bayram

AIM The aim of this study was to assess the relationships among immunohistochemical staining patterns and prognostic factors in patients with non-functioning pituitary adenoma (NFPA). MATERIAL AND METHODS The study included 103 patients who had undergone pituitary surgery for NFPAs. The prognostic factors evaluated were initial tumor size, cavernous sinus invasion, compression of the optic chiasm, recurrence, residual tissue, reoperation, and hypopituitarism. RESULTS Recurrence rates were higher for NFPAs with large initial tumor volume and preoperative cavernous sinus invasion. Tumor recurrence rates were higher for NPFAs positive (55.6%) than negative (10.3%) for luteinizing hormone (LH). Reoperation rate, but not recurrence rate, was higher in patients with tumors positive than negative for follicle-stimulating hormone (FSH) group. Recurrence and reoperation rates were lowest in patients with null-cell adenomas. CONCLUSION In contrast to previous studies, we observed a higher recurrence rate in LH-positive than in LH-negative adenomas. To our knowledge, this is the first study showing an association between LH positivity and poorer prognosis; and in addition, optimal outcomes in patients with null-cell adenomas. Thus, additional studies are required to assess the relationship between LH positivity and poor prognosis in patients with NFPAs.

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