Yazar "Alkan, A." seçeneğine göre listele
Listeleniyor 1 - 7 / 7
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe A 9-year follow-up of a girl with pyridoxine (vitamin B6)-dependent seizures: magnetic resonance spectroscopy findings(Verduci Publisher, 2012) Dogan, M.; Dogan, D. Gumus; Kahraman, A. S.; Ozcan, O.; Yakinci, C.; Alkan, A.Being an extremely rare condition makes the diagnosis of pyridoxine-dependent seizures (PDS) difficult. Early diagnosis of PDS is very important to prevent unwanted clinical outcomes. Elevated levels of glutamate and decreased levels of gamma-aminobutyric acid (GABA) in the frontal and parietal cortices are detected in this disorder. Here we present an 18 year old girl with PDS, who was reported 9 years ago with Magnetic Resonance Spectroscopy (MRS) findings. Present and past MRS findings showed a decrease in N-acetyl-aspartate-to creatine ratio on MRS. In this case it is surprising that neuronal damage has been preceded despite the administration of accurate treatment. That can be because of delay in treatment and/or under treatment.Öğe Bilgisayarlı tomografi eşliğinde perkütan nefrostomi(Türk Üroloji Dergisi/Turkish Journal of Urology, 2003) Baysal, T.; Soylu, A.; Saraç, K.; Alkan, A.; Dusak, A.; Sarıer, M.Öz: Bu çalışmada ultrasonografi veya floroskopi yardımı olmadan bilgisayarlı tomografi (BT) eşliğinde yapılan perkutan nefrostomilerin (PN), özellikle pelvikalisiyel dilatasyonu minimal olan veya hiç olmayan hastalarla, böbrek anatomisi ve yerleşimi normalden farklı hastalardaki yeri araştırıldı. Çalışmaya toplam 40 hastaya BT eşliğinde uygulanan 48 PN'nin (8 hastada bilateral) verileri dahil edildi. Uygulama Seldinger yöntemine uygun olarak yapıldı ve BT hem pelvikalisiyel sisteme iğne girişinde hem de kateter yerleştirmede kullanıldı. Perkutan nefrostomi hastaların tümünde başarıyla gerçekleştirildi. İşlemler sırasında herhangi bir majör komplikasyon gözlenmedi. Perkutan nefrostomi uygulanan 48 böbreğin 28'inde (%58.3) minimal pelvikalisiyel genişleme mevcuttu. Hastaların 4'ünde obezite, 4'ünde ise böbrek rotasyon anomalisi mevcuttu. Bir hastanın böbreği hem ektopik yerleşimli hem rotasyon anomalisine sahipti. Bir hastada önceki PN girişimine bağlı olarak subkapsüler hematom ve bir başka hastada böbrek posterolateraline doğru uzanan kolon segmenti mevcuttu. Perkutan nefrostomi işlemlerinin 18'i interkostal aralıktan yapıldı. Perkutan nefrostomi 35 (%73) işlemde tek iğne girişi ile gerçekleştirilirken. 13 (%27) işlemde ikinci kez tekrarlanan iğne girişi ile pelvikalisiyel sisteme ulaşıldı. İşlem süresi ortalama 28 dk (17-36 dk) idi. Bilgisayarlı tomografi eşliğinde PN obez hastalarda, pelvikalisiyel dilatasyonu olmayan veya minimal olan, böbrek anatomisi ve yerleşimi normalden farklı veya retrorenal yerleşimli kolon varyasyonuna sahip hastalarda güvenle kullanılabilecek komplikasyon oranı düşük, güvenli bir yöntemdir. Başlık (İngilizce): Computed tomography guided percutaneous nephrostomy Öz (İngilizce): Objectives: We investigated the value of computed tomography guided nephrostomies in patients with absent or minimal pelvicaliceal dilatation and with different kidney anatomy and localization without using ultrasound and fluoroscopy. Material and Methods: We attempted 48 computed tomography guided nephrostomy placements in 40 patients. Both puncture of collecting system and placement of the catheters were made under computed tomography guidance. The Seldinger method was used in all procedures. Results: Percutaneous nephrostomies were successfully achieved in all patients without major complications. There were minimal dilatation of the pelvicaliceal systems in 28 (58.3%) of 48 nephrostomies. Four patients had obesity, and another 4 had rotation anomaly. One patient had both ectopic located and malrotated kidney. One patient had subcapsular haematoma and another one had retrorenal colon variation. Eighteen of the percutaneous nephrostomies were made intercostally. Single puncture was used in 35 (73%) and twice puncture were used in 13 (27%) procedures. The time necessary for the procedure ranged from 17-36 min (mean 28 min). Conclusion: Computed tomography guided percutaneous nephrostomy is a safe method with low rate of complications especially in patients with obesity, without pelvicaliceal dilatation or with minimal dilatation and patients with ectopic, malrotated kidneys and retrorenal colon variations.Öğe Brain diffusion-weighted imaging in diabetic patients with retinopathy(Verduci Publisher, 2012) Dogan, M.; Ozsoy, E.; Doganay, S.; Burulday, V.; Firat, P. G.; Ozer, A.; Alkan, A.Objective: Our aim was to detect whether there is any change in apparent diffusion coefficients (ADC) levels in different sites of the brain, particularly in areas associated with the vision, in diabetic patients with retinopathy by measuring diffusion-weighted imaging (DWI). Materials and Methods: Conventional magnetic resonance imaging (MRI) and DWI of the brain were obtained from 45 diabetic patients (15 patients with proliferative diabetic retinopathy (group 1), 15 patients with nonproliferative diabetic retinopathy (group 2), 15 diabetic patients without retinopathy (group 3) and from 15 age-matched healthy volunteers (group 4). ADC values of visual cortex, cingulate gyrus, orbitofrontal, dorsomedial and dorsolateral frontal, corona radiate, and thalamus were obtained. Results: The ADC values of visual cortex, cingulate gyrus and orbitofrontal cortex significantly increased in groups 1 and 2 compared to groups 3 and 4 (p < 0.001). The ADC values of visual cortex significantly increased in group 1 compared to group 2 (p < 0.001). The duration of disease and value of HbA1c positively correlated with ADC values of the visual and orbitofrontal cortexes, and cingulate gyrus. Conclusions: We found an increase in ADC values supporting the neuronal loss in some regions, especially in visual center by DWI in the diabetic patients with retinopathy. This result supports the association between diabetic retinopathy and brain injury.Öğe Effects of electromagnetic radiation produced by 3G mobile phones on rat brains: Magnetic resonance spectroscopy, biochemical, and histopathological evaluation(Sage Publications Ltd, 2012) Dogan, M.; Turtay, M. G.; Oguzturk, H.; Samdanci, E.; Turkoz, Y.; Tasdemir, S.; Alkan, A.Objective: The effects of electromagnetic radiation (EMR) produced by a third-generation (3G) mobile phone (MP) on rat brain tissues were investigated in terms of magnetic resonance spectroscopy (MRS), biochemistry, and histopathological evaluations. Methods: The rats were randomly assigned to two groups: Group I is composed of 3G-EMR-exposed rats (n = 9) and Group 2 is the control group (n = 9). The first group was subjected to EMR for 20 days. The control group was not exposed to EMR. Choline (Cho), creatinin (Cr), and N-acetylaspartate (NAA) levels were evaluated by MRS. Catalase (CAT) and glutathione peroxidase (GSH-Px) enzyme activities were measured by spectrophotometric method. Histopathological analyses were carried out to evaluate apoptosis in the brain tissues of both groups. Results: In MRS, NAA/Cr, Cho/Cr, and NAA/Cho ratios were not significantly different between Groups I and 2. Neither the oxidative stress parameters, CAT and GSH-Px, nor the number of apoptotic cells were significantly different between Groups I and 2. Conclusions: Usage of short-term 3G MP does not seem to have a harmful effect on rat brain tissue.Öğe The effects of selenium on rainbow trout liver treated with heavy metals(Blackwell Publishing, 2006) Talas, Z. Selamoglu; Orun, I.; Alkan, A.; Ozdemir, I.; Erdogan, K.; Yilmaz, I.[Abstract Not Available]Öğe Evaluation of corpus geniculatum laterale and vitreous fluid by magnetic resonance spectroscopy in patients with glaucoma; a preliminary study(Nature Publishing Group, 2012) Doganay, S.; Cankaya, C.; Alkan, A.Purpose To determine whether metabolite changes at cellular level occur in vitreous and lateral geniculate body (LGB) in patients with glaucoma by magnetic resonance spectroscopy (MRS). Methods A total of 29 eyes of 29 patients with glaucoma, no existing ocular pathology and systemic disease (group 1), and 13 eyes of 13 healthy individuals whose routine ophthalmological examinations were normal (group 2) were included in the study. Single-voxel MRS examination was performed by placing region of interest in vitreous and LGB. Glutamate-glutamine (Glx)/creatin (Cr) ratios and lactate peaks in the vitreous, and the Glx/Cr, N-acetyl aspartate (NAA)/Cr, choline (Cho)/Cr ratios in the ipsilateral area of LGB were evaluated. Results A statistically significant difference was found between the two groups for the Glx/Cr ratio in both the vitreous and LGB (P = 0.0001). There was no statistically significant difference between the two groups for the NAA/Cr, and Cho/Cr ratios in the LGB (P = 0.108). A lactate peak was established in the vitreous of 11 glaucoma patients. Conclusion Determining increased Glx/Cr ratios in both the vitreous and LGB of glaucoma patients, supports the theory of apoptosis in the etiopathogenesis of glaucoma. The MRS method, which can measure biochemical structures and metabolites of tissues, and also shows on a single spectrum, may be a new and non-invasive method for confirming the diagnosis of glaucoma and the role of apoptosis in the etiopathogenesis of glaucoma. Eye (2012) 26, 1044-1051; doi:10.1038/eye.2012.84; published online 25 May 2012Öğe Sub-Tenon's steroid irrigation for treatment of intraorbital capillary hemangioma(Sage Publications Inc, 2007) Firat, P. G.; Doganay, S.; Bilak, S.; Alkan, A.A four-month-old male infant underwent sub-Tenon's steroid irrigation for treatment of orbital capilary hemangioma that was causing exposure keratopathy risk to the left eye from progressive proptosis. The temporal inferior sub-Tenon's space was irrigated with a mixture of triamcinolone acetonide (40 mg/ml) and betamethasone sodium phosphate (6 mg/ml) by a blunt-tipped sub-Tenon's cannula. We describe this procedure as irrigation because reflux of the mixture from the incision was permitted. Two weeks after treatment, a marked reduction of proptosis was noted. One month after treatment, the volume of the intraorbital hemangioma resolved significantly in MRI examination. Steroid treatment can be applied local or systemically to treat orbital capillary hemangioma but side effects must be considered carefully. Sub-Tenon's steroid irrigation may be a benefical, effective, pratical and safe application route in the treatment of orbital capillary hemangiomas.
