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Dive into the research topics where Aykut Karasu is active.

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Featured researches published by Aykut Karasu.


Neurosurgery | 2008

LOCALIZATION OF CEREBROSPINAL FLUID LEAKS BY GADOLINIUM-ENHANCED MAGNETIC RESONANCE CISTERNOGRAPHYA 5-YEAR SINGLE-CENTER EXPERIENCE

Kubilay Aydin; Ege Terzibasioglu; Serra Sencer; Altay Sencer; Yusufhan Suoglu; Aykut Karasu; Talat Kırış; M. Inan Turantan

OBJECTIVEIntrathecal gadolinium (Gd)-enhanced magnetic resonance (MR) cisternography is a newly introduced imaging method. Two main objectives of this study were to investigate the sensitivity of Gd-enhanced MR cisternography for presurgical localization of cerebrospinal fluid (CSF) leaks in patients with CSF rhinorrhea and to study the potential long-term adverse effects of intrathecal Gd application. METHODSFifty-one patients (19 women; mean age, 36.2 yr) with CSF rhinorrhea were included in the study. A total of 0.5 ml of Gd was injected into the lumbar subarachnoid space. T1-weighted MR cisternographic images were obtained to detect CSF leakage. The patients neurological states and vital signs were recorded for the first 24 hours after the procedure. Neurological evaluations were repeated 1, 3, and 12 months after the procedure. The patients were followed for at least 3 years with annual neurological examinations. RESULTSGd-enhanced MR cisternography demonstrated CSF leaks in 43 of the 51 patients. The sensitivity of Gd-enhanced MR cisternography for localization of CSF leaks was 84%. Forty-four patients underwent surgery to repair dural tears. Surgical findings confirmed the results of Gd-enhanced cisternography in 43 of the 44 patients who underwent surgery (98%). Eight patients with negative Gd-enhanced MR cisternography had no active rhinorrhea at the time of procedure, and seven of them did not need surgery. None of the patients developed an acute adverse reaction that could be attributed to the procedure. None of the patients developed any neurological symptoms or signs caused by intrathecal Gd injection during a mean follow-up period of 4.12 years. CONCLUSIONGd-enhanced MR cisternography is a sensitive and safe imaging method for detection of CSF leaks in patients with rhinorrhea.


Childs Nervous System | 1997

Anaplastic pleomorphic xanthoastrocytoma

Cicek Bayindir; Naci Balak; Aykut Karasu; Derya Kasaroğlu

A case of anaplastic pleomorphic xanthoastrocytoma (PXA) in a 9-year-old girl is reported. Histological features of PXAs are cellular pleomorphism of GFAP-positive cells, with intracytoplasmic lipidic vacuoles and a reticulin network, bizarre giant cells, low mitotic activity, and lack of necrosis and of endothelial vascular proliferations. These tumors are generally reported to have a favorable postoperative course. In our case, a poor clinical prognosis and spread of the illness through the CSF was observed. Immunohistochemical features of the tumor, which were histologically anaplastic in nature, were analyzed. There were small foci of necrosis in the sections of the material obtained at the first operation and extensive necrosis in that from the second operation, although the patient had not received radiotherapy between the operations. The presence of necrosis in PXA is an uncommon and significant feature. It predicts the poor prognosis seen in this case, and therefore this report strongly supports the notion that necrosis should automatically exclude a tumor from the PXA category. The histological grade was evaluated as grade 3 (according to the WHO classification).


Neurological Research | 2009

Effect of magnesium, MK-801 and combination of magnesium and MK-801 on blood–brain barrier permeability and brain edema after experimental traumatic diffuse brain injury

Murat Imer; Bulent Omay; Ajlan Uzunkol; T Erdem; Pulat Akin Sabanci; Aykut Karasu; Serdar Baki Albayrak; Altay Sencer; Kemal Hepgul; Mehmet Kaya

Abstract Objective: Glutamate antagonists are very attractive drugs in laboratory works to protect neural tissue against ischemia. In this work, the effects of magnesium, MK-801 and combination of magnesium and MK-801 on blood–brain barrier (BBB) and brain edema after experimentally induced traumatic brain injury are evaluated. Methods: A standard closed head injury was induced on the rats by a controlled impact device using a 450-g free falling mass from a height of 2 m onto a metallic disc fixed to the intact skull. One of the following was injected to animals intraperitoneally 30 minutes after injury: saline, magnesium, MK-801 and magnesium plus MK-801. To quantify the brain edema, the specific gravity of the brain tissue was determined. To demonstrate the alteration of the BBB permeability, Evans blue dye was used as a tracer. Results: In all treatment groups, the specific gravity of brain tissue values was significantly higher compared with the control group. Evans blue dye content in the brain tissue was significantly reduced in all three treatment groups with respect to the control group. There was no significant difference of effect between the groups of magnesium alone and MK-801 alone when compared with each other and when compared with their combination. Conclusion: The present data demonstrate that treatment with magnesium, MK-801 and combination of magnesium and MK-801 can reduce formation of brain edema and can help restore BBB permeability after experimental diffuse brain injury.


World Neurosurgery | 2011

Meckel's Cave

Pulat Akin Sabanci; Funda Batay; Erdinç Civelek; Ossama Al Mefty; Muhammad Husain; Saleem I. Abdulrauf; Aykut Karasu

OBJECTIVE To review the microsurgical anatomy of Meckels cave, a detailed knowledge of which is a prerequisite to devising an appropriate surgical strategy and performing successful surgery. METHODS The microsurgical anatomy of Meckels cave was studied under an operating microscope in 15 human cadaver heads (30 sides). To understand the meningeal architecture and the cross-sectional anatomy of Meckels cave, serial histologic sections were made in an additional adult human cadaver specimen. RESULTS Meckels cave is a natural mouth-shaped aperture connecting with the posterior fossa that is located in the medial portion of the middle cranial fossa. The cave extends forward similar to an open-ended three-fingered glove and provides a channel for the rootlets of the trigeminal nerve; the trigeminal ganglion; and the ophthalmic (cranial nerve V(1)), maxillary (cranial nerve V(2)), and mandibular (cranial nerve V(3)) divisions until they reach their respective foramina. The average height of this oval mouth was found to be 4.2 mm (range 3-5 mm) and the average width was 7.6 mm (range 6-8 mm). The mouth of Meckels cave was located 12 mm (range 10-15 mm) superior and medial to the internal acoustic meatus and 6.5 mm (range 5-8 mm) superior and medial to the dural point of entrance of the nervus abducens and 20 mm (range 18-23 mm) medial to the arcuate eminence. CONCLUSIONS Detailed and sound knowledge of the microsurgical anatomy of Meckels cave, which borders on surgically important structures, such as the internal carotid artery and cavernous sinus, is essential to performing precise microneurosurgery in this region. This study describes the complex anatomy of Meckels cave and surrounding structures to provide the knowledge needed to devise a more complete surgical strategy and establish accurate orientation during the surgical procedure.


Surgical Neurology | 2008

Traumatic epidural hematomas of the posterior cranial fossa

Aykut Karasu; Pulat Akin Sabanci; Nail Izgi; Murat Imer; Altay Sencer; Tufan Cansever; Ali Canbolat

BACKGROUND Traumatic EDHs of the posterior cranial fossa are rare and have a higher mortality than supratentorial localizations. Early diagnosis of TEHPCF and prompt surgical evacuation provide excellent recovery. Active use of cranial CT scanning has taken a major role in the diagnosis, surgical indication, close observation, and strategy planning. As a result, better prognosis is achieved. In this study, we represent our results and experiences in the management of TEHPCF. METHODS Between 1993 and 2006, 65 patients with TEHPCF were treated in Istanbul University Faculty Of Medicine, Neurosurgery and Emergency Surgery Departments. The hospital records of these patients were analyzed retrospectively. RESULTS Of 65 patients, whose diagnosis and management decisions were determined by cranial CT scans, 53 were treated through surgery and 12 by conservative methods. Of the 53 surgically treated patients, 2 (3%) patients died, and 2 (3%) other patients remained moderately disabled during their discharge. As a result, 61 (94%) of 65 patients had excellent recovery. CONCLUSION When compared with the literature, our mortality rate was superior to other previously reported studies. In our opinion, this is a result of extensive use of the cranial CT scan together with aggressive surgery. Patients with occipital trauma should be evaluated using cranial CT scans, and those showing mass effect should be immediately treated surgically. The patients that have no mass effect on CT scans can be closely observed by planned serial control CT scans.


Acta Neurochirurgica | 1996

Micro-invasive squamous cell carcinoma arising in a pre-existing intraventricular epidermoid cyst. Case report and literature review.

Cicek Bayindir; N. Balak; Aykut Karasu

SummaryThe authors report the case of a 67-year-old woman with primary micro-invasive squamous cell carcinoma located in the lateral ventricle and originating from an epidermoid cyst. Radiological and histological features of the neoplasm are described and the relevant literature is studied briefly.Two consecutive surgical specimens were studied by light microscopy. In the histological sections of the subtotally removed material of the first operation, the cyst wall was layered by epithelium — the same as expected in an epidermoid cyst — and showed foci with mild to moderate dysplastic changes. Theses changes did not reach up to the degree of a carcinoma. However, because the cyst could not be resected totally, the possibility of a squamous cell carcinoma was considered in the differential diagnosis. In the present case, the diagnosis was firmly established in a second surgical specimen obtained ten months after the first operation. Now, the tumour proved to be a primary squamous cell carcinoma, which exhibited severe dysplastic changes.Primary squamous cell carcinoma of brain is extremely rare. To our knowledge, only 20 such tumours with pre-existing epidermoid cyst have been reported in the central nervous system. The intriguing observation in this case is a three year recurrence free survival following the subtotal removal of the malignant neoplasm at the second surgery, without postoperative radiotherapy.


Surgical and Radiologic Anatomy | 2009

The microsurgical anatomy of the hypoglossal canal

Aykut Karasu; Tufan Cansever; Funda Batay; Pulat Akin Sabanci; Ossama Al-Mefty

BackgroundThe hypoglossal canal (HC) is a region of the skull base whose involvement in many pathological entities is often ignored. Adequate knowledge of the anatomy of the HC and its related bony, neural, and vascular structures is essential for surgery of lesions involving this area.MethodsTen adult human cadaver heads from a US source fixed by formalin (20 sides) and 20 dry human skulls from Indian sources (40 sides) were used in this study. Various aspects of the anatomy of this region including the size, course and variation of the hypoglossal nerve and its relationship to the adjacent and canalicular course were recorded.ResultsThe left HC was located at 10 o’clock and the right HC at the 2 o’clock position with respect to the foramen magnum. The canal was surrounded superiorly by the jugular tubercle, superolaterally by the jugular foramen, laterally by the sigmoid sinus and inferiorly by the occipital condyle. All dry skulls were drilled in the horizontal plane at an axis of about 45° and directed slightly upwards.ConclusionsDetailed knowledge of the microsurgical anatomy of the region of the HC is crucial when performing surgery for lesions of the condylar region, the lower clivus, and ventral brain stem. This study provides the knowledge required to achieve accurate orientation and effective maneuvers during surgical procedures for treatment of the patient without injuring the vital neural and bony structures.


The Neurologist | 2008

Sporadic Multiple Cerebral Cavernomatosis Report of a Case and Review of Literature

Arzu Çoban; Candan Gürses; Bilge Bilgic; Serra Sencer; Aykut Karasu; Nerses Bebek; Betül Baykan; Kemal Hepgul; Aysen Gokyigit

Objective:Cerebral cavernous malformations (CCM) are vascular malformations causing seizures and cerebral hemorrhages. They occur in sporadic and familial forms. Familial cases are associated with a high frequency of multiple lesions, which are less frequently associated with sporadic cases. Case Report:We report a 46-year-old woman presenting with epilepsy with multiple cerebral cavernomatosis on MRI. Because she had had a previous liver transplantation operation, and received immunosuppressants, she was not advised to have a brain operation. However, she had to be operated as a result of a bleeding in one of her cerebral cavernomas. The histologic diagnosis was cavernoma. She has been seizure free after the operation with levetiracetam therapy for the last 17 months. She had no positive family history for both epilepsy and cavernomatosis. Conclusion:When multiple cerebral cavernomatosis are identified in a patient, a detailed neurologic family history should be sought despite the possibility of its being a sporadic case. Our main intention is to present a patient who is surgically controversial and to point out the importance of genetic heredity.


Neuropathology | 2003

Glioblastoma with lymph node metastases

Lora Esberk Ates; Cicek Bayindir; Bilge Bilgic; Aykut Karasu

Metastatic spread of malignant astrocytomas is rare and documented in very few patients with this tumor. Both pathologists and clinicians may confront more of these cases as the patients live longer. We present a 40‐year‐old‐man with glioblastoma multiforme metastasizing to the supraclavicular lymph node after surgery. The tumor was located at the parietal convexity and several lymphadenopathies occured after surgery.


Surgical Neurology | 2009

The first Anatolian contribution to treatment of sciatica by Serefeddin Sabuncuoglu in the 15th century

Gulsat Aygen; Aykut Karasu; Ali Ender Ofluoglu; Glenn Pait; Halil Toplamaoğlu

Serefeddin Sabuncuoglu was an early 15th century surgeon in Anatolia. His masterpiece entitled Cerrahiyetül Haniye (Imperial Surgery) is the first illustrated surgical textbook in the Turkish Islamic literature of the Ottoman era Anatolia. It is the first written medical-surgical work in Anatolian history and it covers the treatment of more than 40 illnesses, which range from hydrocephalus to sciatica. This study aims to investigate the contribution of Anatolia to neurosurgery through Sabuncuoglus treatment of sciatica, a problematic and common illness.

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Talat Kırış

Loma Linda University Medical Center

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Funda Batay

University of Arkansas for Medical Sciences

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