Yazar "Akdemir, Gökhan" seçeneğine göre listele
Listeleniyor 1 - 15 / 15
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Accuracy of fluoroscopically-assisted pedicle screw placement: analysis of 1,218 screws in 198 patients(ELSEVIER SCIENCE INC, 2014) Köktekir, Ender; Ceylan, Davut; Tatarlı, Necati; Karabağlı, Hakan; Recber, Fahri; Akdemir, GökhanBACKGROUND CONTEXT: We retrospectively analyzed a total of 1,218 pedicle screws for accuracy, with postoperative computed tomography (CT), in 198 patients who were operated on between March 2004 and September 2012. PURPOSE: To determine the incidence of screw misplacement in patients who received a transpedicular screw fixation, with intraoperative fluoroscopy in the lateral and lateral with anteroposterior (AP) positions. The results are compared between the two groups. STUDY DESIGN: Retrospective comparative study of accuracy of pedicle screw placement in thoracic and lumbar spine. PATIENT SAMPLE: The sample consists of 198 consecutive patients who underwent transpedicular screw fixation. OUTCOME MEASURES: Accuracy of screw placement was evaluated by postoperative CT scan. Misplacement was defined in cases where more than 25% of the screw size was residing outside the pedicle. METHODS: The indications for hardware placement, radiologic studies, patient demographics, and reoperation rates were recorded. Five hundred twenty-eight screws (Group A, n = 81) were inserted into the vertebral body with the assistance of lateral fluoroscopy only, whereas 690 screws (Group B, n = 117) were inserted with the assistance of lateral fluoroscopy, and the final positions of the screws were checked with AP fluoroscopy. RESULTS: A total of 1,218 screws were analyzed, with 962 screws placed at the lumbosacral region and 256 screws at the thoracic region. According to the postoperative CT scan, 27 screws (2.2%) were identified as breaching the pedicle. Nineteen of them (3.6%) were in Group A, whereas 8 (1.16%) were in Group B. The rate of pedicle breaches was significantly different between Group A and B (p5.0052). In Group A, the lateral violation of the pedicle was seen in 10 screws (1.9%), whereas medial violation was seen in 9 screws (1.7%). In Group B, the lateral violation of the pedicle was seen in six screws (0.87%), whereas medial violation was seen in two screws (0.29%). The medial and lateral penetration of screws were significantly different between Groups A and B (p = .05). A pedicle breach occurred in 21 patients, and 15 of them underwent a revision surgery to correct the misplaced screw. Of these patients, 11 (13.6%) were in Group A, and 4 (3.4%) were in Group B (p = .0335). CONCLUSIONS: In this study, we evaluated and clarified the diagnostic value of intraoperative fluoroscopy in both the lateral and AP imaging that have not yet been evaluated in any comparative study. We concluded that the intraoperative use of fluoroscopy, especially in the AP position, significantly decreases the risk of screw misplacement and the results are comparable with other advanced techniques. (C) 2014 Elsevier Inc. All rights reserved.Öğe B cell aplasia and hypogammaglobulinemia associated with levetiracetam(K FAISAL SPEC HOSP RES CENTRE, 2018) Özdemir, Hülya; Sümer, Sua; Karabağlı, Hakan; Akdemir, Gökhan; Calışkaner, A. Zafer; Artaç, HasibeLevetiracetam (LEV) is a second-generation antiepileptic drug approved for the treatment of several types of epilepsy. We report a 45-year-old female who developed hypogammaglobulinemia and B cell aplasia during LEV treatment. The Naranjo probability score for an adverse drug reaction was 6. After LEV discontinuation, the number of B cells gradually increased and reached normal levels within two months. This case suggests that monitoring of immunoglobulin levels and lymphocyte subsets analysis is important in patients treated with LEV, especially in cases of prolonged infections.Öğe The Cervical Epidural Space Metastasis of Ewing's Sarcoma(2013) Kaptan, Hülagu; Karabağlı, Pınar; Karabağlı, Hakan; Köktekir, Ender; Akdemir, GökhanEwing sarkomu ilk üç dekatda en sık görülen birincil kemik kanserleridir. Kemik ve akciğer metastazları hızlı bir seyir izler. Ewing sarkomunun omurga tutulumu nadir bir klinik durumdur. Lokal ağrı, ele gelen kitle ve nörolojik defisitler Ewing sarkomu tiradını meydana getirir. Omurga Ewing sarkomunun yönetimi ve tedavisinde, cerrahi, radyoterapi ve kemoterapi kombinasyonları yer almaktadır. Omurga Ewing sarkomunun takibinde akut nörolojik kötüleşme dekompresif cerrahiyi öne çıkarır. Bu çalışmada daha önce Ewing sarkomu tanısı almış 32 yaşında erkek bir hastada, medikal onkoloji tarafından izlemdeyken akut nörolojik kötüleşme sonrası üst ekstremite spastik paraparezi ve alt ekstremitede parapleji nedeniyle acil dekompresif cerrahi uygulanması ve sonuçları literatür eşliğinde tartışılmıştır.Öğe The Cervical Epidural Space Metastasis of Ewing's Sarcoma(JOURNAL NEUROLOGICAL SCIENCES, 2013) Kaptan, Hülagu; Karabağlı, Pınar; Karabağlı, Hakan; Köktekir, Ender; Akdemir, GökhanEwing's sarcoma is a primary bone malignancy with the highest incidence in the first to third decades of life. That in both locations follow a rapid course with metastasis to lung and bone. Ewing's sarcoma of the spine is a rare condition that appears with a clinical triad of local pain, neurological deficit and a palpable mass. The definitive management of Ewing's sarcoma of the spine, as in other locations, could include three main modalities: surgery, radiotherapy, and chemotherapy. In the presence of acute neurological decompensation, decompressive surgery via an appropriate approach should be performed. In this study; a 32-year-old male with a sudden progressive severe upper extremity spastic paresis and paraplegy has been presented. We wanted to discuss the preoperative process and treatment modalities.Öğe The cervical epidural space metastasis of Ewing's sarcoma [Ewing's sarkomunun servikal epidural alana metastazi{dotless}](2013) Kaptan, Hülagu; Karabağlı, Pınar; Karabağlı, Hakan; Köktekir, Ender; Akdemir, GökhanEwing's sarcoma is a primary bone malignancy with the highest incidence in the first to third decades of life. That in both locations follow a rapid course with metastasis to lung and bone. Ewing's sarcoma of the spine is a rare condition that appears with a clinical triad of local pain, neurological deficit and a palpable mass. The definitive management of Ewing's sarcoma of the spine, as in other locations, could include three main modalities: surgery, radiotherapy, and chemotherapy. In the presence of acute neurological decompensation, decompressive surgery via an appropriate approach should be performed. In this study; a 32-year-old male with a sudden progressive severe upper extremity spastic paresis and paraplegy has been presented. We wanted to discuss the preoperative process and treatment modalities.Öğe Fluorodeoxyglucose positron emission tomography/computed tomography findings in a patient with cerebellar mutism after operation in posterior fossa(ELSEVIER SINGAPORE PTE LTD, 2017) Gedik, Gonca Kara; Sarı, Oktay; Köktekir, Ender; Akdemir, GökhanCerebellar mutism is a transient period of speechlessness that evolves after posterior fossa surgery in children. Although direct cerebellar and brain stem injury and supratentorial dysfunction have been implicated in the mediation of mutism, the pathophysiological mechanisms involved in the evolution of this kind of mutism remain unclear. Magnetic resonance imaging revealed dentatothalamocortical tract injuries and single photon emission computed tomography showed cerebellar and cerebral hypoperfusion in patients with cerebellar mutism. However, findings with F-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in this group of patients have not been documented previously. In this clinical case, we report a patient who experienced cerebellar mutism after undergoing a posterior fossa surgery. Right cerebellar and left frontal lobe hypometabolism was shown using FDG PET/CT. The FDG metabolism of both the cerebellum and the frontal lobe returned to normal levels after the resolution of the mutism symptoms. (C) 2017 Asian Surgical Association and Taiwan Robotic Surgical Association. Publishing services by Elsevier B.V.Öğe Intracranial Giant Tuberculoma Mimicking Brain Tumor: A Case Report(TURKISH NEUROSURGICAL SOC, 2015) Sümer, Sua; Köktekir, Ender; Demir, Nazlım Aktuğ; Akdemir, GökhanTuberculomas are small tumor-like lumps that can be seen, usually in large numbers, in central nervous system involvement of tuberculosis. Giant tuberculomas that are big enough to cause symptoms of compression are also encountered, though rarely. When they are really large, tuberculomas may result in increased intracranial compression, neurologic deficits, or epileptic attacks. Giant tuberculomas may be confused with brain tumors on cranial magnetic resonance imaging. Cranial magnetic resonance imaging and histopathology examinations are used for diagnosis. Although magnetic resonance imaging is useful for diagnosing tuberculoma, histopathology examination is the gold standard for a final diagnosis. This paper presents a case involving a 66-year-old patient who complained of headache, imbalance and dizziness, and underwent an operation in the neurosurgery clinic with a pre-diagnosis of brain tumor, and was then diagnosed with intracranial giant tuberculoma.Öğe Lung Adenocarcinoma Metastasis to Frontal Sinus Mimicking Pott's Puffy Tumor(LIPPINCOTT WILLIAMS & WILKINS, 2013) Köktekir, Ender; Köktekir, Bengü Ekinci; Reçber, Fahri; Akdemir, GökhanMetastasis of the lung adenocarcinoma to the paranasal sinuses is a rare clinical entity. We present a 75-year-old male patient who presented with swelling of the forehead and left upper eyelid with proptosis in left eye due to metastasis from lung adenocarcinoma. It appears as a puffy swelling of the forehead like a Pott's puffy tumor. Pott's puffy tumor is a subperiostal abscess of the frontal bone associated with osteomyelitis and usually occurs as a complication of sinusitis or trauma.Öğe Neuroprotective effect of aquaporin-4 deficiency in a mouse model of severe global cerebral ischemia produced by transient 4-vessel occlusion(ELSEVIER IRELAND LTD, 2014) Akdemir, Gökhan; Ratelade, Julien; Asavapanumas, Nithi; Verkman, A. S.Astrocyte water channel aquaporin-4 (AQP4) facilitates water movement across the blood-brain barrier and into injured astrocytes. We previously showed reduced cytotoxic brain edema with improved neurological outcome in AQP4 knockout mice in water intoxication, infection and cerebral ischemia. Here, we established a 4-vessel transient occlusion model to test the hypothesis that AQP4 deficiency in mice could improve neurological outcome following severe global cerebral ischemia as occurs in cardiac arrest/resuscitation. Mice were subjected to 10-min transient bilateral carotid artery occlusion at 24h after bilateral vertebral artery cauterization. Cerebral blood flow was reduced during occlusion by >94% in both AQP4(+/+) and AQP4(-/-) mice. The primary outcome, neurological score, was remarkably better at 3 and 5 days after occlusion in AQP4(-/-) than in AQP4(+/+) mice, and survival was significantly improved as well. Brain water content was increased by 2.8 +/- 0.4% in occluded AQP4(+/+) mice, significantly greater than that of 0.3 +/- 0.6% in AQP4(-/-) mice. Histological examination and immunofluorescence of hippocampal sections at 5 days showed significantly greater neuronal loss in the CA1 region of hippocampus in AQP4(+/+) than AQP4(-/-) mice. The neuroprotection in mice conferred by AQP4 deletion following severe global cerebral ischemia provides proof-of-concept for therapeutic AQP4 inhibition to improve neurological outcome in cardiac arrest. (C) 2014 Elsevier Ireland Ltd. All rights reserved.Öğe Obstructive hydrocephalus caused by giant basilar artery aneurysm(RIYADH ARMED FORCES HOSPITAL, 2013) Kaptan, Hülagu; Köktekir, Ender; Reçber, Fahri; Akdemir, GökhanGiant basilar artery aneurysms are rarely associated with hydrocephalus. When it occurs the treatment usually addresses the hydrocephalus rather than the aneurysm itself, especially if it is already thrombosed. The treatment options include ventriculoperitoneal shunting and endoscopic third ventriculostomy, which may be related to high complication rates. However, reducing the intracranial hypertension may produce aneurysmal growth. We report a patient with obstructive hydrocephalus due to thrombosed giant basilar artery aneurysm. The patient initially presented with symptoms of increased intracranial pressure, and was managed by ventriculoperitoneal shunting with significant symptomatic improvement. Fifteen days after operation, the patient died due to a cerebrovascular event. We report a case that deteriorated because of cerebral infarction due to aneurysmal growth after ventriculoperitoneal shunting. We also discuss the treatment options in such cases.Öğe Resolution of papilledema after endoscopic third ventriculostomy versus cerebrospinal fluid shunting in hydrocephalus: a comparative study Clinical article(AMER ASSOC NEUROLOGICAL SURGEONS, 2014) Köktekir, Ender; Köktekir, Bengü Ekinci; Karabağlı, Hakan; Gedik, Şansal; Akdemir, GökhanObject. In this study the authors compare the efficacy of endoscopic third ventriculostomy (ETV) versus CSF shunting for resolution of papilledema in hydrocephalus. Methods. This comparative case series study recruited 12 patients (24 eyes) with hydrocephalus who underwent either an ETV (Group 1, 6 patients [12 eyes]) or CSF shunt treatment (Group 2, 6 patients [12 eyes]). A complete ophthalmological examination including retinal nerve fiber layer (RNFL) evaluation by optical coherence tomography was provided for all patients before surgery and in the 1st week, 1st month, and 3rd month postoperatively. The 2 groups were compared for quantitative changes in RNFL thickness and, thereby, resolution of papilledema. Statistical evaluation was performed using the Mann-Whitney U-test with the aid of SPSS version 16.0. Results. The mean preoperative RNFL thickness was 259.7 +/- 35.8 mu m in Group 1 and 244.5 +/- 53.4 mu m in Group 2 (p = 0.798). The mean decrease in RNFL thickness was 101.3 +/- 38.8 mu m, 141.2 +/- 34.6 mu m, and 162.0 +/- 35.9 mu m in Group 1 versus 97.0 +/- 44.6 mu m, 143 +/- 45.6 mu m, and 130.0 +/- 59.8 mu m in Group 2 for the postoperative 1st week, 1st month, and 3rd month, respectively. There was no significant difference between the two groups with respect to decrease in RNFL thickness during the 1st week, 1st month, and 3rd month (p = 0.563, p = 0.753, and p = 0.528, respectively). Conclusions. This is the first study to quantitatively evaluate papilledema in assessing the success of ETV and CSF shunting. The authors' results indicated that ETV is as effective as CSF shunting with respect to decreasing intracranial pressure and resolution of papilledema.Öğe Symptomatic Pneumorrhachis(THIEME MEDICAL PUBL INC, 2014) Köktekir, Ender; Tatarlı, Necati; Ceylan, Davut; Köktekir, Bengü Ekinci; Akdemir, GökhanPneumorrhachis (PR) is the presence of air within the spinal canal, whether localized in the epidural or in the subarachnoid space. Evidence of intraspinal air, especially in the subarachnoid space, had been thought to be merely a radiological artifact of serious underlying pathology until it was proven that PRs can be related to neurologic symptoms ranging from radicular pain to serious neurologic deficits. The etiologies, pathomechanisms, and natural courses show differences from case to case, with the result that no consistent treatment strategies exist in the literature. Although the conservative treatment modalities seem to be more appropriate in nonsymptomatic cases, treatment strategies in symptomatic cases remain the subject of discussion. In this study, we present two symptomatic cases of PR arising from different causes and review the literature, focusing especially on the symptomatic cases and strategies for treating them.Öğe An Unusual Mechanism of Delayed Intracerebral Hemorrhage After Ventriculoperitoneal Shunting: Case Report(2012) Koktekir, Ender; Tatarli, Necati; Ceylan, Davut; Karabaglı, Hakan; Akdemir, GökhanBu olgu sunumunda ventriküloperitoneal şant cerrahisinden 7 yıl sonra geç gelişen bir intraserebral hemoraji olgusunu sunuyoruz. 7 yaşında erkek hasta acil servise ani başlayan baş ağrısı ve kusma şikayetleri ile başvurdu. Bilgisayarlı beyin tomografi incelemesi,ventriküler katater etrafında intraserebral hemoraji varlığını gösteriyordu. Hastanın öyküsü,labaratuvar bulguları ve radyolojik incelemelerinde intraserebral hemorajiye neden olabilecek kafa travması, kanama diyatezi, vasküler malformasyon ve intratümoral hemoraji saptanmadı. Bu vakada intraserebral hemorajiye yol açan tahmini mekanizma, çocuğun büyüme döneminde boyun bölgesinde gerilmiş olan şant tüpü nedeni ile ventriküler kataterin gerilmesi ile oluşan serebral dokunun kontüzyonuydu.Öğe An Unusual Mechanism of Delayed Intracerebral Hemorrhage After Ventriculoperitoneal Shunting: Case Report(Ege University Press, 2012) Koktekir, Ender; Tatarlı, Necati; Ceylan, Davut; Karabağlı, Hakan; Akdemir, GökhanWe present a case of delayed intracerebral hemorrhage that developed seven years after initial ventriculoperitoneal shunt surgery. A seven-year-old boy was admitted to emergency when he experienced sudden headache and vomiting. Computed tomography (CT) scanning showed an intracerebral hemorrhage around the ventricular catheter that cannot be explained by known predisposing factors such as head trauma, coexisting bleeding disorder, occult vascular malformation, and intratumoral hemorrhage. The presumed mechanism in this case is that the ventricular catheter caused contusion of cerebral tissue because the shunt tube at the neck had stretched during the growing up of the child.Öğe An Unusual Mechanism of Delayed Intracerebral Hemorrhage After Ventriculoperitoneal Shunting: Case Report(JOURNAL NEUROLOGICAL SCIENCES, 2012) Köktekir, Ender; Tatarlı, Necati; Ceylan, Davut; Karabağlı, Hakan; Akdemir, GökhanWe present a case of delayed intracerebral hemorrhage that developed seven years after initial ventriculoperitoneal shunt surgery. A seven-year-old boy was admitted to emergency when he experienced sudden headache and vomiting. Computed tomography (CT) scanning showed an intracerebral hemorrhage around the ventricular catheter that cannot be explained by known predisposing factors such as head trauma, coexisting bleeding disorder, occult vascular malformation, and intratumoral hemorrhage. The presumed mechanism in this case is that the ventricular catheter caused contusion of cerebral tissue because the shunt tube at the neck had stretched during the growing up of the child.
