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  • Küçük Resim
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    Effect of visible light on vasospasticity of post-subarachnoid hemorrhage cerebrospinal fluid
    (Thieme Medical Publ Inc, 2017) Sabancı, Pulat Akın; Omay, Bülent; Aras, Yavuz; Aydöşeli, Aydın; Ali, Ahmet; Erdem, Tülin; Sencer, Altay; Kırış, Talat
    Background and Objective Cerebral vasospasm (CV) is a serious complication of subarachnoid hemorrhage (SAH) with high morbidity and mortality rates. The mechanism of CV has not been determined. There are many theories related to this unsolved issue, one of which supports CV as a two-stage phenomenon from a pathophysiologic perspective. The first stage consists of inhibition of neuronal nitric oxide synthase by oxyhemoglobin, which results in a decrease of nitric oxide (NO) production. The second stage consists of an increase in the levels of asymmetric dimethylarginine through bilirubin oxidation products (BOXes), which are oxidized by-products of hemoglobin metabolism. These in turn inhibit endothelial nitric oxide synthase (eNOS), which results in the blockage of the second NO production mechanism. BOXes are sensitive to visible light, as is their precursor bilirubin. The hypothesis of CV prevention using the photosensitivity of BOXes was tested in this study. Material and Methods Cerebrospinal fluid (CSF) obtained from two patients with SAH was divided in half and either exposed to a standard dose of visible light or not exposed to any light. The CSF was spectrophotometrically investigated and the concentration of BOXes was measured. A comparison between CSF samples exposed to light and not exposed to light was made. Using two groups of 16 rats each, the vasospastic effect of the CSF exposed and not exposed to light on arteries of the cortical surface was measured. The cortex was exposed using the cranial window. Results Spectrophotometric analysis revealed that the concentration of BOXes in the CSF decreased significantly after being exposed to visible light ( p <0.001). There was a significant difference of the vasospastic effect of CSF on exposed cortical arteries ( p <0.001). Conclusion The concentration of BOXes and the vasospastic effect of CSF taken from patients with SAH were significantly reduced after being exposed to visible light if compared with CSF not exposed to light.
  • Küçük Resim
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    Fully endoscopic interlaminar and transforaminal lumbar discectomy: analysis of 47 complications encountered in a series of 835 patients
    (Elsevier Espana Slu, 2017) Yörükoğlu, Ali Güven; Göker, Burcu; Tahta, Alican; Akçakaya, Mehmet Osman; Aydoseli, Aydın; Sabancı, Pulat Akın; Aras, Yavuz; Alkır, Görkem; Sencer, Altay; Imer, Murat; İzgi, Nail; Canbolat, Ali Tuncay
    Objective: To report perioperative complications in fully endoscopic lumbar discectomy (FELD). Methods: From September 2010 to November 2016, 835 patients underwent FELD. In total, 865 disc levels were operated on. Of the 835 patients, the transforaminal (TF) approach was used in 174 patients, while 691 patients were operated on using the interlaminar (IL) approach. Surgical complications occurred in 47 patients, which were retrospectively analyzed. Results: Neurological deficits occurred in six patients. In four of these six patients, deficits resolved spontaneously. In one patient, symptoms resolved after a laminectomy procedure. In only one case, the neurological deficit was permanent. Seven patients complained of dysesthesia, which resolved spontaneously with medical treatment in four patients. In the remaining two patients, dysesthesia symptoms improved after epidural and foraminal injections. Dural tears were encountered in 26 patients. Pudendal neuralgia occurred in three patients. 'Itvo cases showed wound infection. The other complications comprised one disc infection, one retroperitoneal hematoma and one wrong level surgery. Conclusion: The FELD procedure has a steep learning curve and it is a difficult procedure to master. Surgeons should be aware of complications that can occur with the FELD procedure, most of which resolve spontaneously. (C) 2017 Sociedad Espanola de Neurocirugia. Published by Elsevier Espana, S.L.U. All rights reserved.