Bulent Duz | Gulhane Military Medical Academy (original) (raw)

Papers by Bulent Duz

Minimally Invasive Neurosurgery, Sep 1, 2000

Epidural cavernous angiomas are apparently rare lesions. We present a case of paraplegia with acu... more Epidural cavernous angiomas are apparently rare lesions. We present a case of paraplegia with acute onset secondary to spinal epidural cavernous angioma at levels C7 and T1. Magnetic resonance imaging gave the clinician the opportunity to diagnose the lesion preoperatively. In this article, we present and discuss this rare case with a review of the literature.

Microvascular Research, Jul 1, 2002

Hypoxic condition in the brain result in microvascular dysfunction. Pericytes are one of the bloo... more Hypoxic condition in the brain result in microvascular dysfunction. Pericytes are one of the blood-brain barrier constituents with the endothelial cells and astrocytes. Pericytes of blood-brain barrier are the first cells to react to hypoxia of brain. We showed, at the ultrastructural level, microvascular pericyte responses to the brain hypoxia in early stage of hypoxia in cats. In first 2 h of hypoxia, pericytes start to migrate and one of every three pericytes migrates from original location. In the first stage of migration spikes occur at the abluminal surface of pericytes. At the same time basal lamina thickens and endothelial cells remain the same.

Turkish Neurosurgery, 2014

Salivary gland tumors constitute 3% of tumors in the body. Salivary gland tumors constitute 4% to... more Salivary gland tumors constitute 3% of tumors in the body. Salivary gland tumors constitute 4% to 10.80% of all tumors in the head and neck tumors and most of them originate from the parotid gland. Most salivary gland tumors are benign. Basal cell adenocarcinoma is a rare salivary gland tumour. Most appear to be benign clinically. Metastases have occurred in less than 10% of patients. A 58-year-old female patient was admitted with the complaint of a growing mass at the top of her head. She was operated for parotid adenocarcinoma two years ago. Computed Tomography (CT) was performed to clarify the relationship between the mass with the calvarium and intracranial region. There is a risk of malignancy in scalp and calvarium lesions. Patients must be subjected to preoperative radiological evaluations.

Spine, Sep 1, 2008

Analysis of the patients with spinal missile injury (SMI). Choosing the optimum treatment for SMI... more Analysis of the patients with spinal missile injury (SMI). Choosing the optimum treatment for SMI with respect to bullet trajectory, evaluation of surgical indications, and timing of surgical intervention. A few guidelines were reported for the management of SMI. But there is still no consensus about the indication and timing of the surgery. The relationship between the surgery and bullet trajectory was not reported previously. One hundred twenty-nine patients with spinal missile injury were admitted to our department from 1994 to 2006 and 122 of them could be functionally monitored. Functional recovery and complications in surgical and conservative treatment groups were evaluated. Surgical indications were discussed. The injuries were classified with respect to the bullet&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s trajectory. Seventy-four patients were treated surgically, of whom 60 (81%) had incomplete injuries. All 17 patients whose vertebral column was injured with side-to-side trajectory were operated on because of instability. In the surgical group, 33 (56.9%) showed improvement, 20 (34.5%) showed no change, and 5 (8.6%) worsened. The best results were obtained by the patients who received operations because of rapid neurologic decline, compression, and instability in the spinal canal (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001). Twenty-three (31%) complications and associated injuries were seen in the surgically treated patients and 18 (34.6%) were seen in the conservatively treated patients. Anteroposterior and oblique trajectories [Gulhane Military Medical Academy (GATA)-SMI I and GATA-SMI II] of SMI must be recognized as highly infective in the lumbar region. A side-to-side trajectory (GATA-SMI III) missile causing spinal cord injury is unstable and needs further stabilization. The spinal cord is not injured by the GATA-SMI IV trajectory, and thus, the best approach in this case is conservative. The best results from neurosurgical interventions may be achieved after rapid neurologic deteriorations because of spinal compression and/or instability.

Neurology India, 2010

Radial nerve is the most frequently injured major nerve in the upper extremity. Proximal part of ... more Radial nerve is the most frequently injured major nerve in the upper extremity. Proximal part of the radial nerve involvement can result from a humerus fracture, direct nerve trauma, compression and rarely from tumors. The aim of the study is to determine the clinical characteristics and electrodiagnostic findings in patients with proximal radial nerve injuries, and also the outcome of surgical treatment. The study subjects included 46 patients with radial nerve injuries seen between June 2000 and June 2008 at our hospital. The analysis included demographics, clinical features, etiology, pre-and postoperative EMNG (Electromyoneurography) findings. Surgical decompression resulted in neurological improvement in patients with radial entrapment neuropathies. Good neurological recovery was observed from decompression of callus of old humeral fracture. The worst results were observed in the direct missile injuries of the radial nerve. A detailed clinical and electrodiagnostic evaluation is of importance in patients with radial nerve injury to ensure an appropriate treatment. The choice of treatment, conservative or surgical, depends on the clinical presentation and the type of injury.

Multi-Staged Endoscope-Assisted Microsurgical Resection of A Triventricular Choroid Plexus Carcin... more Multi-Staged Endoscope-Assisted Microsurgical Resection of A Triventricular Choroid Plexus Carcinoma Erhan TURKOGLU, Bora GURER, Onder ONGURU, Bulent DUZ Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Neurosurgery Clinic, Ankara, Türkiye Gulhane Military Medical Academy and School of Medicine, Department of Pathology, Ankara, Türkiye Gulhane Military Medical Academy Haydarpaşa Hospital, Department of Neurosurgery, Istanbul, Türkiye

Neurosurgery Quarterly, Sep 1, 2009

Abstract We present an extremely rare case report of a primary intramedullary malignant melanoma ... more Abstract We present an extremely rare case report of a primary intramedullary malignant melanoma arising into the cervical spinal cord. We describe and review clinical presentations, characteristic findings from imaging studies, diagnostic criteria, prognosis, ...

Neurologia I Neurochirurgia Polska, Jul 1, 2015

World Neurosurgery, 2022

BACKGROUND The orbit is an eloquent organ of the body. Safe surgical access to the orbit could be... more BACKGROUND The orbit is an eloquent organ of the body. Safe surgical access to the orbit could be challenging due to the dense network of critical structures confined to it. There are versatile approaches to different parts of the orbit that could be used by neurosurgeons without causing injury to critical neurovascular structures. In this study, we aimed to present our surgical experience with the transconjunctival approach through the bulbar conjunctiva to anterior intraorbital lesions caused by diverse pathologies. METHODS We conducted a retrospective review of cases with intraorbital lesions operated via the transconjunctival approach by the same senior surgeon between 2015 and 2017. All patients were evaluated before the surgery by computed tomography (CT), magnetic resonance imaging (MRI), and plain anteroposterior and lateral radiographs. RESULTS Five patients underwent surgery by the transconjunctival approach through the medial or lateral routes for different pathologies: cavernoma, lymphoma, inflammatory reaction, meningocele, and foreign body. No complications were recorded, and all patients were satisfied with their clinical and esthetic results. CONCLUSION The transconjunctival approach is a safe, effective, and time-sparing surgical approach to diverse pathologies in the anterior orbit. Navigation systems enhance the ability to maneuver in selected cases. The transconjunctival approach could be performed in collaboration with ophthalmologists since it provides better esthetic outcomes and higher satisfaction rates in operated patients.

The Journal of Spinal Cord Medicine, 2008

Neurosurgery, 2008

OBJECTIVE The clinical presentation, biomechanical evaluation, and surgical techniques for repair... more OBJECTIVE The clinical presentation, biomechanical evaluation, and surgical techniques for repairing cervical meningoceles in adulthood are presented. Cervical meningoceles are typically diagnosed in childhood and are rarely reported among spinal dysraphic lesions in adulthood. In most cases, the cervical spinal cord is found tethered to the dura and other soft tissues by fibrous or fibroneural elements. Cervical lesions, unlike those that arise more caudally, rarely leak cerebrospinal fluid. METHODS We report 5 male patients with meningoceles, aged 20 to 22 years (mean age, 20.4 years), in whom the primary evolution of the lesion occurred between 1999 and 2006. RESULTS All 5 patients presented to the hospital with cervical pain and mass. One patient had had a cerebrospinal fluid leak from the center of the lesion intermittently since birth. Another patient presented with neurological deficits and hypesthesia of the left hand. All patients underwent surgery. The lesion was excised, ...

Acta Neurochirurgica, 2008

Background Evolving of a single centre by means of different transsphenoidal approaches during th... more Background Evolving of a single centre by means of different transsphenoidal approaches during the survey of methodological advances in pituitary surgery is presented. Materials and methods Ninety-three consecutive patients with pituitary adenomas underwent transphenoidal pituitary operations at Gulhane Military Medical Academy from January 1996 to October 2007. Retrospective chart-based analysis of the surgical methods of transsphenoidal pituitary adenoma operations were done. Surgical methods were described. Outcomes and complications were presented. Attention is focused on the methodology of different surgical techniques of pituitary surgery.

Turkish Journal of Physical Medicine and Rehabilitation, 2017

Objectives: This study aims to evaluate facet tropism in younger patients with lumbar spondylolys... more Objectives: This study aims to evaluate facet tropism in younger patients with lumbar spondylolysis and to investigate the role of facet tropism in the development of spondylolysis. Patients and methods: Between February 2013 and December 2015, a total of 102 male patients with bilateral L5 pars defect including 53 with spondylolysis and 49 control subjects were included in this case-control study. The facet joint angles were measured bilaterally and axially at the level of L3-4, L4-5, L5-S1 using computed tomography (CT). The classification was made as follows: A difference between two reciprocal facet joint angles of <6° indicated no tropism, 6°-12° indicated moderate tropism, and >12° indicated severe tropism. Results: A total of 612 angles including 318 facet joint angles from 53 patients with spondylolysis and 294 facet joint angles from 49 control subjects were measured. L3-4 measurements in the control group showed no tropism in 87.8% (n=43), moderate tropism in 12.2% (n=6), and severe tropism in 0% (n=0). L4-5 measurements in control group showed no tropism in 79.6% (n=39), moderate tropism in 20.4% (n=10), and severe tropism in 0% (n=0). L5-S1 measurements in the control group showed no tropism in 69.4% (n=34), moderate tropism in 28.6% (n=14), and severe tropism in 2.0% (n=1). The mean facet joint angles in the spondylosis group were 32.9±5.1°, 37.5±5.4°, and 41.2±7.8° at the levels of L3-4, L4-5, and L5-S1, respectively. The mean facet joint angles of the control group were 33.2±5.7°, 39.7±4.9°, and 42.2±4.9° at the levels of L3-4, L4-5, and L5-S1, respectively, indicating no significant difference between the right and left mean facet joint angles between the groups (p>0.05). The frequency of facet tropism and the difference between right and left facet joint angles for all three levels were significantly higher in the spondylolysis group (p<0.05). Facet tropism at the level of L5-S1 was significantly more frequent than facet tropism at L3-4 level (p<0.05). Conclusion: Our study results show that the rate of facet joint tropism is higher in the patients with spondylolysis, suggesting that facet tropism seems to play a role in the etiology of spondylolysis as a predisposing factor.

Minimally Invasive Neurosurgery, 2007

Dermoid and epidermoid cysts are congenital, slowly growing tumours that usually become symptomat... more Dermoid and epidermoid cysts are congenital, slowly growing tumours that usually become symptomatic when patients reach the middle of their third decade. An otherwise healthy 20-year-old man presented with an epileptic attack. Imaging studies including computed tomography and magnetic resonance imaging revealed an intradural cystic lesion located in the anterior subfrontal region. Choices of traditional approaches for such a lesion are a bicoronal craniotomy or a transfacial procedure. Taking the advantage of the endoscope, the authors decided to remove the lesion via an endonasal route. After a fully endoscopic endonasal operation, gross total resection of the dermoid tumour was achieved. We have not observed cerebrospinal fluid leakage or any infectious complication after the operation. In this report the technique of operation and reconstruction method are described. The endoscopic endonasal approach offers a good option for lesions located in the anterior skull base. Carefully piecemeal resection of the tumour while preserving the underlying neural and vascular structures should be the main strategy of the operation. Reconstruction is very important after the surgery and a carefully planned pedicled graft technique may help in the prevention of cerebrospinal fluid leakage.

Turkish Neurosurgery, Feb 1, 2009

Aim: Traumatic brain injury (TBI) caused by a gunshot wound is a complex injury with a broad spec... more Aim: Traumatic brain injury (TBI) caused by a gunshot wound is a complex injury with a broad spectrum of symptoms and high rates of mortality and morbidity. This study presents an evaluation of TBI caused by gunshot wounds presenting at a single institution and discusses possible predictive factors for the outcome of surgical intervention. Material and methods: The study sample consisted of 442 patients who underwent surgery for TBI over a 16-year period. All injuries were caused by gunshot wounds, such as bullets and shrapnel. All patients underwent surgical intervention. Results: Almost all patients (99.3%) were male, and the mean patient age was 22.3 years. Wounds were caused by shrapnel in 68 percent of patients. The Glasgow Coma Scale (GCS) score at admission was below 8 in 116 patients (26.2%) and above 8 in 326 patients (73.8%). In total, 47 patients (10.6%) died despite surgical management, with diffuse brain injury the most common cause of death. Conclusion: Low GCS scores, ventricular injuries and bihemispheric injuries are correlated with poor prognosis. Early and less invasive surgery in conjunction with short transportation time to the hospital could decrease mortality rates.

Neurosciences, Apr 1, 2012

To study the effects of pre-ischemic hyperbaric oxygen (HBO) and post-ischemic aminoguanidine (AG... more To study the effects of pre-ischemic hyperbaric oxygen (HBO) and post-ischemic aminoguanidine (AG) on the infarct volume in permanent middle cerebral artery occlusion. This study was approved by the Animal Experiments Ethics Committee of Gulhane Military Medical Academy, Ankara, Turkey and carried out from March 2006 to August 2006. A total of 28 Sprague-Dawley rats (200-320 g) were divided into 4 groups: control (K) group (n = 7); HBO group (n = 7); HBO + AG group (n = 7); and the AG group (n = 7). All rats underwent middle cerebral artery occlusion (MCAO) by subtemporal craniectomy, and permanent ischemia was created. A 2.8 atmospheric pressure of HBO was first applied to the HBO and HBO + AG groups for 45 minutes, and occlusion was created after 2 hours. In the HBO + AG group, intraperitoneal administration of AG hemisulfate (100 mg/kg) was started 6 hours after MCAO, and was continued twice a day for 3 days. The rate of infarction was found to be 22.2+/-3.1% in the control group, 16.1+/-2.7% in the HBO group, 15.2+/-1.9% in the HBO+AG group, and 14.4+/-3.3% in the AG groups. The rate of infarctions (therefore the volume of infarct) in the HBO, HBO + AG, and AG groups were found to be significantly decreased compared with the control group (p=0.002, p=0.001, and p=0.001). In permanent MCAO-induced ischemia in rats, HBO and AG were observed to have a lowering effect on the infarct volume, but no additive effect was observed. This situation can be explained by different mechanisms of action.

Oligodendrogliomas rarely occur in the posterior fossa of childhood and constitute approximately ... more Oligodendrogliomas rarely occur in the posterior fossa of childhood and constitute approximately 1% of pediatric brain tumors. Only six pediatric posterior fossa oligodendroglioma cases have been reported to date and none of them were cystic. The authors present a seven-year-old girl with cystic, cerebellar midline localized tumor. A standard suboccipital craniectomy was performed and the tumor was histologically confirmed as oligodendroglioma. After operation the patient underwent radiation therapy and at one the-year follow-up, no recurrence of the tumor was observed.

Turkish Neurosurgery, 2010

Aim: This study was planned for detailed evaluation of electrophysiological findings in patients ... more Aim: This study was planned for detailed evaluation of electrophysiological findings in patients with adult TCS. Material and methods: Patients were retrospectively assessed for clinical, radiological and electrophysiological data between 1999 and 2008. Tibial somatosensorial evoked potentials, needle electromyography, nerve conduction studies and late responses (H reflex and F response) were studied in thirty (1 female, 29 males) TCS patients diagnosed by lumbar magnetic resonance imaging. Results: Tibial somato-sensorial evoked potentials cortical response latency was abnormal in 18 (60%) patients. Needle electromyography revealed chronic neurogenic involvement in 13 (43.3%) patients. In nerve conduction studies, motor unit action potential amplitudes were reduced in 5 (16.6%) patients and H reflexes were abnormal in 13 (43.3%) patients. Conclusion: Different electrophysiological abnormalities may be seen in patients with adult TCS. Our results indicated that tibial SEP abnormalities are most sensitive electrophysiological finding in patients with adult TCS. Patients with TCS should undergo electrophysiological examinations whether they have subjective or objective complaints. These examinations should evaluate different systems and treatment planning should be done with the data obtained.

Turkiye Klinikleri Journal of Neurosurgery Special Topics, 2008