Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Hakan Karabagli is active.

Publication


Featured researches published by Hakan Karabagli.


Journal of Clinical Neuroscience | 2010

Outcomes of gamma knife treatment for solid intracranial hemangioblastomas.

Hakan Karabagli; Ali Genc; Pinar Karabagli; Ufuk Abacioglu; Askin Seker; Turker Kilic

The aim of this study was to examine the results of gamma knife radiosurgery for 13 patients with residual/recurrent or newly diagnosed solid hemangioblastomas. The 13 patients had 34 solid hemangioblastomas, and all patients underwent gamma knife radiosurgery. Seven patients had von Hippel-Lindau disease and six had sporadic disease. When individual lesions were considered, the overall mean dose at the tumor periphery was 15.8 Gy (range: 12-25 Gy) and the average maximum tumor dose was 31.6 Gy (range: 24-50 Gy). The mean duration of follow-up with MRI was 50.2 months. At the last follow-up evaluation, growth control was achieved for all tumors (partial remission in three tumors [8.8%] and no change in 31 tumors [91.2%]). No radiation-related complications were encountered. Our findings reinforce the view that gamma knife radiosurgery is effective and safe for the management of solid hemangioblastomas with a diameter less than 3 cm, whether they are sporadic or associated with von Hippel-Lindau disease. The high response rate and lack of any radiation-induced side-effects confirms the suitability of the doses used in the present study.


The Spine Journal | 2014

Accuracy of fluoroscopically-assisted pedicle screw placement: analysis of 1,218 screws in 198 patients.

Ender Koktekir; Davut Ceylan; Necati Tatarlı; Hakan Karabagli; Fahri Recber; Gokhan Akdemir

BACKGROUND 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 (p=.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.


Childs Nervous System | 2014

Currarino syndrome: report of five consecutive patients.

Soner Duru; Hakan Karabagli; Erhan Turkoglu; Yusuf Erşahin

IntroductionThe Currarino syndrome is regarded as a developmental disorder based on its recognized etiological heterogeneity. This syndrome is thought to result from abnormal separation of the neuroectoderm from the endoderm. Our aim was to report the neurosurgical management of Currarino syndrome in children and adults and to describe what clinician could do if the Currarino triad was suspected.Case reportsWe present five cases of Currarino triad who underwent surgical intervention. All patients had sacral bony deformity, anorectal malformations, and anterior sacral meningocele. A 40-year-old-male had chronic constipation. He was incidentally diagnosed with Currarino syndrome. A 19-year-old-female suffered from a slight weakness in lower extremities and urinary incontinence. Her past medical history was remarkable for anal atresia. The other three cases were children.ConclusionWhen an anterior sacral meningocele is encountered, Currarino syndrome should be taken into consideration. Although it is rarity, the Currarino syndrome might be one of the causes of chronic constipation. Endoscopic or endoscope-assisted surgery via a posterior sacral route can be feasible for treatment of some of the patients with anterior sacral meningocele. Anterior meningocele pouch associated with Currarino syndrome will regresses over time following transdural ligation of its neck.


Brain Tumor Pathology | 2014

Desmoplastic non-infantile astrocytic tumor with BRAF V600E mutation

Pinar Karabagli; Hakan Karabagli; Dogan Kose; Nadir Koçak; Volkan Etus; Yavuz Koksal

Desmoplastic infantile astrocytomas (DIA) are rare neoplasms of infancy which are defined by a combination of distinctive clinicopathologic features. DIA was originally defined in 1982 by Taratuto et al. as meningocerebral astrocytoma attached to dura with desmoplastic reaction. In 1993, it was included in the WHO classification under the term ‘desmoplastic cerebral astrocytoma of infancy’ [1]. DIA accounts for 1.25 % of pediatric brain tumors [2]. The large majority of cases presents within the first 24 months of life [1, 3]. Non-infantile cases are rarely encountered with only eight cases reported before [3–10]. However, in two of these cases, clinical symptoms ensued within the first year of life [4, 5]. Less is known about the molecular etiology of DIA [1, 11]. Recent studies suggest that certain types of mostly low grade and pediatric brain tumors may have higher rates of BRAF alterations. BRAF V600E mutations have been detected in small series of pediatric gangliogliomas, pleomorphic xanthoastrocytomas, desmoplastic infantile gangliogliomas and atypical teratoid/ rhabdoid tumors as well as pediatric glioblastomas, anaplastic astrocytomas and diffuse astrocytomas [11–15].


Laryngoscope | 2012

Is the use of topical fluorescein helpful for management of CSF leakage

Kayhan Ozturk; Hakan Karabagli; Serap Bulut; Meryem Egilmez; Mutlu Duran

We aimed to evaluate the effectiveness of topical intranasal fluorescence application together with high‐resolution computed tomography and magnetic resonance imaging and/or magnetic resonance cisternography for the preoperative diagnosis of cerebrospinal fluid (CSF) leakage and for intraoperative localization of CSF fistulas. We also assessed postoperative recurrence.


Neuropathology | 2014

Aggressive rhabdoid meningioma with osseous, papillary and chordoma‐like appearance

Pinar Karabagli; Hakan Karabagli; Guler Yavas

Meningiomas are the most common primary intracranial tumors. They are usually benign and slowly growing; however, they may show histologically malignant features categorizing them into grade II or III of World Health Organization (WHO) classification. Rhabdoid meningioma (RM) is an uncommon meningioma variant categorized as WHO grade III. The clinical course of RM is determined by local recurrences, invasion of adjacent brain and/or dura, widespread leptomeningeal dissemination, remote metastases and fatal clinical outcome. Herein we report a case with recurrent aggressive left occipital parasagittal region RM in which the patient initially declined radiation treatment. The tumor was resected four times in 5 years. Histopathological examination revealed a rhabdoid meningioma with metaplastic, papillary and chordoid differentiation. Six months after her fourth operation the patient died of progressive disease. RM is a rare subtype of malignant meningioma and the role of different adjuvant therapeutic options are still unknown. Clinical presentation, radiological features and pathologic findings of this uncommon tumor are discussed.


Turkish Neurosurgery | 2016

Early endoscopic ventricular irrigation for the treatment of neonatal posthemorrhagic hydrocephalus. a feasible treatment option or not ? -a multi center report-

Volkan Etus; Gokmen Kahilogullari; Hakan Karabagli; Agahan Unlu

AIM Neonatal intraventricular hemorrhage (IVH) usually results in posthemorrhagic hydrocephalus (PHH). This multicenter study describes the approach of early neuroendoscopic ventricular irrigation for the treatment of IVH/PHH and compares the results with the cases that have been initially treated only with conventional temporary cerebrospinal fluid (CSF) diversion techniques. MATERIAL AND METHODS The data of 74 neonatal PHH cases, that have been treated at three pediatric neurosurgery centers, were retrospectively analyzed. 23 neonates with PHH underwent early endoscopic ventricular irrigation (Group-A). 29 neonates were initially treated with conventional methods (Group-B). 22 neonates underwent ventriculosubgaleal shunt placement (Group-C). Complications, shunt dependency rates, incidence of multiloculated hydrocephalus and incidence of CSF infection were evaluated and compared retrospectively. RESULTS Group-A, Group-B and Group-C cases did not differ significantly regarding gestational age and birth weight. In Group-A, 60.8% of the patients required a later shunt insertion, as compared with 93.1% of the cases in Group-B and 77.2% of the cases in Group-C. Group-A patients were also associated with significantly fewer CSF infections as well as significantly lower incidence for multiloculated hydrocephalus development as compared with Group-B and Group-C. CONCLUSION Early removal of intraventricular blood degradation products and residual hematoma via neuroendoscopic ventricular irrigation is feasible and safe for the treatment of PHH in neonates with IVH. Neuroendoscopic technique seems to offer significantly lower shunt rates and fewer complications such as infection and development of multiloculated hydrocephalus in those cases.


The Spine Journal | 2015

Holospinal epidural abscess in a child patient: magnetic resonance imaging findings.

Mustafa Koplay; Mesut Sivri; Melike Keser Emiroglu; Ibrahim Guler; Hakan Karabagli; Yahya Paksoy

A 5-year-old male patient was admitted to our hospital with fever lasting 2 days, numbness in feet, and walking disorder. There were restrictions of movement in both lower extremities, and two dermal sinus openings were found 3 cm and 10 cm cranial to anal region in physical examination. There were no risk factors in patient history, and infection markers such as sedimentation, C-reactive protein (CRP), and procalcitonin values were elevated. Spinal magnetic resonance imaging was performed, and there was a fluid collection consistent with abscesses extending between C4 and L4 vertebrae segments, showing continuity along the posterolateral spinal cord, having a maximum thickness of 15 mm and millimetric air intensities on lumbar segments, hypointense on T1-weighted images (WI), hyperintense on T2-WI, and showing peripheral enhancement after intravenous contrast administration. Likewise, an additional fluid collection consistent with epidural


Childs Nervous System | 2018

Cauda equina syndrome in a patient diagnosed with type 1 Gaucher disease: a rare case

M. Sahinoglu; A. Mutlukan; E. Koktekir; Hakan Karabagli

BackgroundGaucher disease is a rare hereditary glycolipid storage disease. One of the rare complications is neurodeficits due to vertebral involvement.Case presentationAn 18-year-old female patient presented to the outpatient clinic with cauda equina syndrome due to sacral involvement of type 1 GD. Bilateral laminectomy via posterior approach without posterior stabilization was performed.ConclusionMaximum excision of the mass avoiding destabilization of the spinal column can provide long-term vertebral stability and improvement in neurodeficits.


Turkish Neurosurgery | 2017

Can hypo/hypernatremic conditions be a factor for na ion channel kinetics: model study

Murat Ayaz; Hakan Karabagli; Sirma Yanardag

AIM Dysnatremic cases are frequently faced in clinical practice. Its macroscopic effects and consequences are well known, but microscopic effects are not well defined. The aim of this study was to reveal the effects of dysnatremia at the cellular level. MATERIAL AND METHODS By using an action potential simulation, the effects of extracellular sodium (Na) concentration on the Na ion channel kinetics were studied. The experimental sets were chosen to mimic hypo/hypernatremic conditions and, in both cases, the degree of the severity was varied. RESULTS Hyponatremic situations through modifying the axonal Na+ channels kinetics result in the rundown of the sodium current (INa). The degree of the hyponatremia-dependent effect seen in the Na ion channel is severity dependent, which is more effective in the recovery phase of the ion channel. Hypernatremic conditions, on the other hand, have also affected the Na ion channel activity through modifying the kinetics of the channel. Unlike hyponatremia, the effect seen in hypernatremic conditions was through decreasing the response time of the channel. The degree of the significance of the effect seen on the Na ion channel in the case of the hypernatremia was found to be less destructive compared to the hyponatremic condition. CONCLUSION The Na channels are susceptible to the changes of the extracellular Na concentrations. Thus, the underestimation of hypo/hypernatremic conditions can put patients in danger and close monitoring of serum Na level might be required.

Collaboration


Dive into the Hakan Karabagli's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge