Ramazan Buyukkaya
Düzce University
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Publication
Featured researches published by Ramazan Buyukkaya.
The Journal of Clinical Endocrinology and Metabolism | 2015
Ender Karaca; Ramazan Buyukkaya; Davut Pehlivan; Wu-Lin Charng; Kürşat Oğuz Yaykaşlı; Yavuz Bayram; Tomasz Gambin; Marjorie Withers; Mehmed M. Atik; İlknur Arslanoğlu; Semih Bolu; Serkan Erdin; Ayla Buyukkaya; Emine Yaykasli; Shalini N. Jhangiani; Donna M. Muzny; Richard A. Gibbs; James R. Lupski
CONTEXT Pituitary stalk interruption syndrome (PSIS) is a rare, congenital anomaly of the pituitary gland characterized by pituitary gland insufficiency, thin or discontinuous pituitary stalk, anterior pituitary hypoplasia, and ectopic positioning of the posterior pituitary gland (neurohypophysis). The clinical presentation of patients with PSIS varies from isolated growth hormone (GH) deficiency to combined pituitary insufficiency and accompanying extrapituitary findings. Mutations in HESX1, LHX4, OTX2, SOX3, and PROKR2 have been associated with PSIS in less than 5% of cases; thus, the underlying genetic etiology for the vast majority of cases remains to be determined. OBJECTIVE We applied whole-exome sequencing (WES) to a consanguineous family with two affected siblings who have pituitary gland insufficiency and radiographic findings of hypoplastic (thin) pituitary gland, empty sella, ectopic neurohypophysis, and interrupted pitiutary stalk-characteristic clinical diagnostic findings of PSIS. DESIGN AND PARTICIPANTS WES was applied to two affected and one unaffected siblings. RESULTS WES of two affected and one unaffected sibling revealed a unique homozygous missense mutation in GPR161, which encodes the orphan G protein-coupled receptor 161, a protein responsible for transducing extracellular signals across the plasma membrane into the cell. CONCLUSION Mutations of GPR161 may be implicated as a potential novel cause of PSIS.
Clinical Imaging | 2014
Ramazan Buyukkaya; Nalan Yildirim; Hakan Cebeci; Hasan Kocaeli; Abdurrahim Dusak; Gokhan Ocakoglu; Cuneyt Erdogan; Bahattin Hakyemez
BACKGROUND AND PURPOSE The purpose of this study is to investigate the relationship between Rosenthal basal vein (BVR) type and diameter and perimesencephalic nonaneurysmal subarachnoid hemorrhage (P-SAH). MATERIALS AND METHODS Aneurysmal subarachnoid hemorrhage (A-SAH), P-SAH, and control groups were evaluated, and BVRs were classified by type. BVR diameters in patients were measured. RESULTS There was a statistically significant difference of BVR drainage types between groups (P=.002). BVR diameters of patients with normal drainage pattern in P-SAH group were significantly smaller than those in both other groups (P<.001). CONCLUSION There is a relationship between P-SAH and BVR primitive drainage type. P-SAH risk increases in parallel with decreasing caliber of BVR in patients with normal drainage pattern.
European Journal of Radiology | 2009
Hakan Uzun; Burhan Yazici; Besir Erdogmus; Kenan Kocabay; Ramazan Buyukkaya; Ayla Buyukkaya; Ömer Yazgan
OBJECTIVE The aim of this study was to investigate the effect of fatty infiltration of the liver (FIL) on the Doppler waveform pattern in the hepatic veins of obese children. METHODS In this prospective study, 59 patients with diffuse FIL and 45 normal healthy children who served as control group underwent hepatic vein B-mod and duplex Doppler sonography. The Doppler sonography spectrum of the right hepatic vein was classified into three groups: triphasic waveform, biphasic waveform, and monophasic or flat waveform. RESULTS There was a statistically significant difference in the phasicity of hepatic venous flow between patients and control subjects (p<0.001). The Doppler flow pattern in the right hepatic vein was triphasic in 28 (47.5%), biphasic in 28 (47.5%), and monophasic in 3 (5%) children with fatty liver, while it was triphasic in 43 (95.6%) and biphasic in 2 (4.4%) control subjects. There was an inverse correlation between the sonographic grade of fatty infiltration of the liver and the phasicity of hepatic venous flow (r=-0.479, p<0.001). CONCLUSIONS Abnormal right hepatic vein Doppler waveform, biphasic as well as monophasic, can be seen in healthy obese children with diffuse FIL.
Interventional Neuroradiology | 2014
Ramazan Buyukkaya; Hasan Kocaeli; Nalan Yildirim; Hakan Cebeci; Cuneyt Erdogan; Bahattin Hakyemez
This study describes the peri-procedural and late complications and angiographic follow-up results of 32 patients with 34 complex aneurysms treated with flow diverter Silk stents in a single centre. In this retrospective study, 40 Silk stents (SS) were implanted in 34 complex intracranial aneurysms in 32 patients. In our series, 20 (58.8%) carotid-ophthalmic internal carotid artery (ICA), six (17.6%) cavernous ICA, two (5.9%) supraclinoid ICA, two (5.9%) petrosal ICA (the same patient- bilateral) and four (11.8%) posterior circulation aneurysms were treated. One of the posterior circulation lesions was a fenestrated-type aneurysm. Twenty wide-necked, saccular; eight neck remnant; four fusiform and two blister-like aneurysms were included in our series. SS were successfully implanted in all patients (100%). Misdeployment occurred in 17.6% of patients. In two of these patients adequate stent openness was achieved via Hyperglide balloon dilatation. Coil embolization in addition to SS placement was utilized in four aneurysms. One patient (3%) experienced transient morbidity due to a thromboembolic event and there was one mortality (3%) due to remote intraparenchymal haemorrhage. Complete occlusion of 27/33 (81.8%) and 29/33 (87.9%) aneurysms was achieved six and 12 months after the procedure, respectively. In-stent intimal hyperplasia was detected in 6.1% patients. Flow-diverter Silk stent implantation is an effective method of treating complex aneurysms with acceptable mortality and morbidity rates. Complete occlusion is achieved in most of the complex aneurysms.
World journal of emergency medicine | 2015
Harun Gunes; Hayati Kandis; Ayhan Saritas; Süber Dikici; Ramazan Buyukkaya
BACKGROUND Weather conditions are thought to increase the risk of stroke occurrence. But their mechanism has not yet been clarified. We investigated possible relationships between ischemic stroke and weather conditions including atmospheric pressure, temperature, relative humidity, and wind speed. METHODS One hundred and twenty-eight patients with ischemic stroke who had been admitted to our hospital between January 1 and December 31, 2010 were enrolled in this study. We investigated the relationship between daily cases and weather conditions the same day or 1, 2, and 3 days before stroke. RESULTS A negative correlation was found between maximum wind speed and daily cases 3 days before stroke. As the relationship between daily cases and changes of weather conditions in consecutive days was evaluated, a negative correlation was found between daily cases and change of atmospheric pressure in the last 24 hours. CONCLUSIONS The maximum wind speed 3 days before stroke and change of atmospheric pressure in the last 24 hours were found to increase the cases of ischemic stroke. We recommend that individuals at risk of ischemic stroke should pay more attention to preventive measures, especially on days with low maximum wind speed, on subsequent 3 days, and on days with low atmospheric pressure in the last 24 hours.
American Journal of Emergency Medicine | 2014
Ramazan Buyukkaya; Ömer Aydın; Bahattin Hakyemez; Dogan Seref
Spontaneous spinal epidural hematoma is a very rare clinical emergency. A permanent neurological deficit or even death may result if diagnosis and treatment are delayed. Many cases can be diagnosed upon detailed neurological examination and magnetic resonance (MR) imaging. Usually, surgery is required, but rarely, the condition may improve spontaneously. A 46-year-old male patient was admitted to our emergency department because of rapidly evolving severe paraplegia following development of sudden-onset neck pain. Spinal MR imaging detected an epidural hematoma compressing the spinal cord at the C5–T1 level. Clinical and radiological follow-up showed that the patient recovered spontaneously in 48 hours without any need for surgical treatment.
Acta Radiologica | 2007
Besir Erdogmus; Burhan Yazici; H. I. Onder; C. Bilgin; A. Tugay; Ramazan Buyukkaya
Purpose: To investigate the effect of exhaust particles on orbital blood flow velocity of the ophthalmic artery, central retinal artery, and posterior ciliary artery by color Doppler ultrasonography in highway toll collectors. Material and Methods: Color Doppler imaging was used to measure the peak-systolic and end-diastolic flow velocities and resistivity indices of the ophthalmic artery, central retinal artery, and posterior ciliary artery in 20 toll collectors and 20 controls. Results: Both the peak-systolic and the end-diastolic flow velocities were decreased in the ophthalmic artery, central retinal artery, and posterior ciliary artery, and the resistivity index was increased in the central retinal artery in toll collectors when compared with control groups. Results were considered statistically significant if P<0.05. Conclusion: It was determined that the effect of exhaust particles reduced ocular blood flow velocity in toll collectors as measured by color duplex Doppler ultrasonography.
Seminars in Ophthalmology | 2015
Mustafa Ozsahin; Ramazan Buyukkaya; Fahri Halit Besir; Halil Ibrahim Onder; Besir Erdogmus; Safinaz Ataoğlu; Derya Guclu; Rumeysa Kolukisa
Abstract Purpose: To analyze the hemodynamic features of orbital blood flow velocities using Doppler ultrasonography in ankylosing spondiylitis (AS) patients, as well as to compare these results with those of healthy controls. Methods: 33 AS patients and 32 healthy controls were consecutively included in the study groups. The same radiologist performed ocular blood flow measurements. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured in the central retinal artery (CRA), posterior ciliary arteries (PCAs), and ophthalmic artery (OA). Resistive index was used to assess arterial resistance; it was automatically calculated as RI [(PSV–EDV)/PSV]. Results: There were no significant differences in the PSV, EDV, and RI of the OA, CRA, and PCAs between AS patients and controls. Conclusion: This result suggests no possible contributory role of vascular structures in formation of uveitis in AS. We believe that our preliminary results need to be complemented with further studies, particularly including AS patients with uveitis and rheumatic diseases with other ocular involvement.
American Journal of Emergency Medicine | 2015
Ayla Buyukkaya; Harun Gunes; Mehmet Ali Özel; Ramazan Buyukkaya; Omer Onbas; Ayhan Saritas
Morel-Lavallee syndrome is a posttraumatic soft tissue injury in which the subcutaneous tissue is broken off from the underlying fascia, creating a cavity filled with hematoma and liquefied fat. It commonly occurs over the greater trochanter and, rarely, may also occur in the lumbal region.Morel-Lavallee syndrome can be often diagnosed late because of ommitted diagnosis in emergency services. The emergency physician and radiologist must keep this syndrome in mind because early diagnosis can enable conservative management, whereas delayed diagnosis may lead to surgical exploration. In this article,we present the clinical and radiologic features of 2 cases of lumbar Morel-Lavallee syndrome detected after trauma.
Diagnostic and Interventional Radiology | 2016
Omer Fatih Nas; Mehmet Fatih İnecikli; Kadir Hacikurt; Ramazan Buyukkaya; Guven Ozkaya; Fahir Ozkalemkas; Ridvan Ali; Cuneyt Erdogan; Bahattin Hakyemez
PURPOSE We aimed to assess the effectiveness, benefits, and reliability of percutaneous vertebroplasty (PV) in patients with vertebral involvement of multiple myeloma. METHODS PV procedures performed on 166 vertebrae of 41 patients with multiple myeloma were retrospectively evaluated. Most of our patients were using level 3 (moderate to severe pain) analgesics. Magnetic resonance imaging was performed before the procedure to assess vertebral involvement of multiple myeloma. The following variables were evaluated: affected vertebral levels, loss of vertebral body height, polymethylmethacrylate (PMMA) cement amount applied to the vertebral body during PV, PMMA cement leakages, and pain before and after PV as assessed by a visual analogue scale (VAS). RESULTS Median VAS scores of patients decreased from 9 one day before PV, to 6 one day after the procedure, to 3 one week after the procedure, and eventually to 1 three months after the procedure (P < 0.001). During the PV procedure, cement leakage was observed at 68 vertebral levels (41%). The median value of PMMA applied to the vertebral body was 6 mL. CONCLUSION Being a minimally invasive and easily performed procedure with low complication rates, PV should be preferred for serious back pain of multiple myeloma patients.