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Hasan Kocaeli

Publications and source records attributed to Hasan Kocaeli.

14 recordsLinked to original sources

Impact of novel PTEN mutations in Turkish patients with glioblastoma multiforme.

Glioblastoma multiforme (GBM) represents the most common and aggressive type of primary neoplasms of the central nervous system. The PTEN (phosphatase, tensin homologue, deleted on chromosome TEN; MIM # 601728) tumor suppressor gene has an essential biological role in the formation of glioblastomas. It is known that there are variations in genetic alterations in tumors that develop in patients with different ethnic backgrounds and because there is no study evaluating PTEN mutation in Turkish patients with GBM, we aimed to realize the present study. We investigated 62 GBM tumors for mutations of the PTEN gene using single strand conformational polymorphism (SSCP) method followed by DNA sequencing. As a result of our investigation, PTEN mutations were detected in 15 of 62 tumors (24.19%). Nine different sequence variants were identified: one novel promoter site mutation (5'UTR -9C-->T), one novel intronic mutation (IVS2-2delA), four novel point mutations (61A-->G, 105T-->G, 248C-->G, and 364C-->G), two novel frameshift mutations (213delC) and 378delGATA) and one previously reported global exonic transition type mutation (129G-->A). Since the majority of PTEN mutations identified in the present study are novel, we believe that these alterations may be specific to Turkish population. Furthermore, though no significant correlation was found between PTEN mutations and histopathological properties of GBM tumors, our findings indicate that localizations of mutations in PTEN gene may have an effect on clinical aggressiveness of GBM tumors.

Adult↗

Glioblastomatous recurrence of oligodendroglioma remote from the original site: a case report.

BACKGROUND: As in all diffuse gliomas, recurrence is an inherent feature of oligodendrogliomas, either as the same or higher grade neoplasm at the primary site. The rate of remote recurrence after surgery for the primary tumor cannot be estimated from the scarce literature, but delayed treatment of the primary tumor and genetic alterations may be associated with this phenomenon. CASE DESCRIPTION: A 40-year-old man presented with generalized seizures. A magnetic resonance imaging scan disclosed a right frontal mass lesion showing features of a low-grade glioma for which he refused any treatment. Seven months after diagnosis upon uncontrollable seizures, he underwent a stereotactic biopsy, which was followed by a right frontal craniotomy, both of which confirmed the lesion as a grade 2 oligodendroglioma. Six months after surgery, the patient presented with a left frontal lobe GBM without evidence of recurrence at the primary site. The genetic analysis of the primary and recurrent tumors showed trisomy 7, monosomy 10, but not 1p or 19q deletions, which have been proposed as markers for favorable prognosis. CONCLUSION: Recurrence of a frontal lobe oligodendroglioma remote from the primary site as a GBM is a rare occurrence. Single-cell invasion across the corpus callosum with subsequent or simultaneous malignant degeneration into a secondary GBM is the likely mechanism. As the genetic analysis suggests, conversion of oligodendroglioma to GBM may be associated with gain of chromosome 7, loss of chromosome 10, and other genetic markers that may represent late events in the oncogenesis of oligodendroglial tumors.

Adult↗

Meningiomas with conventional MRI findings resembling intraaxial tumors: can perfusion-weighted MRI be helpful in differentiation?

INTRODUCTION: To investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors. METHODS: We retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student's t-test was used for statistical analysis. RESULTS: On CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58+/-2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02+/-1.40 and 4.68+/-1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P<0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve. CONCLUSION: Differentiating meningiomas with atypical conventional MRI findings from malignant intraaxial tumors can be difficult. Calculation of rCBV ratios and construction of signal intensity-time curves may contribute to the differentiation of meningiomas from intraaxial tumors.

Aged↗

Cerebrospinal fluid leakage complicating skull base fractures: analysis of 81 cases.

The aim of this study was to evaluate the results of conservative and surgical management options for traumatic cerebrospinal fluid (CSF) leakage complicating skull base fractures. The subjects were 81 patients who were treated between 1996 and 2003 for CSF leaks that had persisted for 24 h or longer after head injury. For each case the medical records were reviewed, and the data collected were as follows: demographic features, clinical and radiological findings, management options, complications and outcome scores. Analysis was done with patients grouped according to Glasgow coma scale (GCS) score at admission ( 8), and findings for three treatment methods (conservative, CSF drainage, surgery) were evaluated. In 32 cases (39.5%), the CSF leakage resolved spontaneously, and the mean hospital stay for these patients was 14+/-11 days. Twenty-four patients (29.6%) were treated by CSF drainage, and seven of these individuals ultimately required surgery to close the leak. Hospital stay was 17+/-7 days. Twenty-five patients (30.9%) underwent surgery as the initial treatment step, and the mean hospital stay for these individuals was 15+/-9 days. The large majority (74.2%) of patients with admission GCS scores 8 resolved spontaneously. The factors that had a critical influence on outcome in this series were level of consciousness on admission and presence of additional intracranial pathology associated with CSF leakage within cases of traumatic CSF fistulae due to skull base fractures. Treatment decisions should be dictated by the severity of neurological decline during the emergency period and the presence/absence of associated intracranial lesions. The timing for surgery and CSF drainage procedures must be decided with great care and with a clear strategy. The authors offer a treatment algorithm.

Adolescent↗

Medial portion of the cavernous sinus: quantitative analysis of the medial wall.

Pituitary tumors invade the cavernous sinus via the medial wall. Researchers have speculated that this wall is composed of dura and that substances secreted by tumors might damage this barrier. In contrast to the lateral wall, little is known about the structure of the medial wall of the cavernous sinus (MWCS). This study provides the first detailed quantitative (thickness) and qualitative (histological) assessment of the MWCS. Eighteen sellar-parasellar tissue blocks were obtained from adult human autopsies. Ten specimens were used for microsurgical dissection and macroscopic anatomical description. Eight specimens were used for histopathological study and for recording computer measurements of MWCS thickness. Each of these eight specimens was divided into three approximately equal-sized pieces, with cuts made in the coronal plane from posterior to anterior starting at the anterior level of the pituitary stalk. Wall thicknesses were compared in the three different regions (posterior, middle, anterior), and also on the left vs. the right sides. The investigations showed that the MWCS is a distinct dural layer that forms a barrier between the medial venous space of the cavernous sinus and the pituitary gland. The mean thickness of the 48 total (left and right) MWCS observed in the 24 sections examined was 0.195 +/- 0.066 mm (range = 0.080-0.387 mm). This wall is composed of loosely arranged collagen fibers that comprise a specific layer known as "meningeal dura." The posterior third of the MWCS was significantly thinner than the middle third (P = 0.0014) or anterior third (P = 0.0001). No macro- or microscopic defects were observed in any of the MWCS in the 18 specimens. The thinness of the posterior MWCS suggests that this is the most likely path for extension of pituitary tumors into the cavernous sinus.

Cavernous Sinus↗

Quadrigeminal cistern lipoma.

Intracranial lipomas are rare benign congenital neoplasms accounting for 0.1 to 0.5% of all primary brain tumours. Approximately 50% are associated with other cerebral developmental disorders. These slow growing benign lesions are usually asymptomatic and rarely require surgery. We report the case of a 37 year old woman presented with signs of raised intracranial pressure. Computerized tomography and magnetic resonance imaging demonstrated a quadrigeminal cistern lipoma compressing the aqueduct of Sylvius. The patient underwent surgery and a distinct plane of cleavage between the lipoma and the adjacent neural structures was found, allowing total removal of the lesion. Postoperatively, the patient was relieved of her original symptoms but developed akinetic mutism which lasted for two weeks. Intracranial lipomas rarely become symptomatic and surgery is seldom required. If the lesion progresses and causes symptoms of raised intracranial pressure or compression of neural structures, surgical intervention is indicated. Total removal should not be attempted unless a plain of cleavage between the lesion and adjacent neural structures is present. Surgical manipulation should be minimised to avoid complications.

Adult↗

MK-801 improves neurological and histological outcomes after spinal cord ischemia induced by transient aortic cross-clipping in rats.

BACKGROUND: Glutamergic excitotoxicity has been shown to play a deleterious role in the pathophysiology of ischemic spinal cord injury (ISCI). The aim of this study was to investigate the neuroprotective effect of a single dose of MK-801, an antiexcitotoxic drug, in a rat model of ISCI. METHODS: Ischemic spinal cord injury was induced for 17 minutes in Sprague-Dawley rats using direct aortic arch, just proximal to the left common carotid artery, plus left subclavian artery cross-clamping through a left-sided limited thoracotomy. Study groups were as follows: control group (n = 8) receiving only vehicle and experimental group (n = 8) receiving a single dose of MK-801 (1 mg/kg IV) 10 minutes before aortic clamping. Neurological examination was performed at 6 hours, 24 hours, and daily up to 96 hours. Rats were sacrifice at methylprenisolone socium succinate 96 hours, and spinal cords were removed for histopathology. RESULTS: All the control rats had severe permanent neurological deficits after ISCI, whereas the MK-801-treated rats had statistically (P < .05) better neurological outcome and good recovery. Histopathology revealed severe neuronal necrosis in the lumbar gray matter of control rats, whereas MK-801-treated rats showed mild injury. CONCLUSION: These results demonstrate that combined temporary clipping of the aortic arch (just proximal to the left common carotid artery) plus left subclavian artery for 17 minutes reproduces reliable paraplegia, and a single dose of MK-801 given before ISCI provides significant neuroprotection.

Animals↗

Large cavernous hemangioma of the frontal bone.

A 53-year-old woman presented with a rare case of cavernous hemangioma of the frontal bone manifesting as right frontal stabbing headache and local swelling. Computed tomography revealed an extensive, well-defined, radiolucent, osteolytic lesion in the right frontal bone. The inner and outer tables of the skull were eroded and the lesion had compressed the brain parenchyma. Right frontal craniotomy was performed, and the lesion with a 1 cm-wide margin of surrounding uninvolved bone was removed. The defect was reconstructed with titanium mesh. The patient did well after the operation. The cosmetic results were satisfactory and follow up at 6 months post-surgery revealed no recurrence.

Diagnosis, Differential↗

Critical care management of severe head injury in children.

BACKGROUND: Our aim was to analyze prognostic factors and their association with outcome among children with severe head injury. METHODS: We conducted a retrospective study among children (n=55) with severe head injury [Glasgow Coma Score (GCS) ?8] who were admitted to our Neurosurgical Intensive Care Unit (ICU) from January 1996 to September 2003. The patients were immediately evaluated with cranial computed tomography (CT) for the severity of head injury as well as for the causes of secondary insults such as hypoxia and hypotension, metabolic and hematological alterations. Outcome analysis was assessed according to Glasgow Outcome Scale Score (GOS) six months after the injury. RESULTS: A poor result occurred in 31 patients (57%) while 24 patients (43%) had favourable results. Multivariate analysis showed significant independent prognostic effect for admission mean systolic blood pressure, presence of hypoxia, multiple trauma, admission GCS score and multiple intracranial lesions (p<0.05). Admission WBC counts and serum glucose levels were not correlated with GOS. CONCLUSION: This study describes clinicoradiologic findings and prognostic factors regarding severe head injury in pediatric patients. The goals of managements of pediatric patients with severe traumatic head injury include normalizing intracranial pressure, optimizing arterial blood gases and systemic blood pressure, and prevention of factors that exacerbate secondary brain injury.

Adolescent↗

Sella turcica metastasis from follicular carcinoma of thyroid.

A case of metastasis to the sella turcica from a follicular adenocarcinoma of the thyroid gland is presented. Metastasis to this site is rare and review of the literature reveals only 12 cases of metastatic thyroid carcinoma involving the sella turcica and pituitary gland. The optimal treatment strategy is still to be determined. A 43-year-old woman presented with headache, nausea, visual impairment and galactorrhea. An MRI scan of the cranium revealed an enhancing destructive sellar lesion. The patient underwent transsphenoidal removal of the lesion to alleviate visual loss. The histological features of the sellar tumor were identical to those of a follicular adenocarcinoma partially removed from the thyroid gland 22 months earlier. Total thyroidectomy followed by three courses of iodine-131 ablation enhanced with synthetic thyrotropin and thyroid hormone suppression therapy was instituted. The post-operative course was satisfactory with improved vision and ceased galactorrhea. This case was successfully treated with a combination of surgical removal, iodine-131 ablation and hormone suppression therapy, which resulted in disease control duration of four years. Sella turcica metastases of thyroid carcinoma are exceedingly rare and currently there are no established therapeutic guidelines.

Adenocarcinoma, Follicular↗

Trigeminal neuralgia caused by a pontine abscess: case report.

OBJECTIVE AND IMPORTANCE: Various intracranial abnormalities, including infectious conditions, may manifest as trigeminal neuralgia. CLINICAL PRESENTATION: A 33-year-old man presented with a 15-day history of right-sided facial pain and numbness. Neurological examination revealed diminished corneal reflex and facial sensation in the right V(1)-V(2) distribution. Magnetic resonance imaging revealed a contrast-enhancing lesion centered at the right pons with extension of the enhancement to the sphenoid sinus. INTERVENTION: Broad-spectrum antibiotics were administered for 6 weeks. This resulted in alleviation of symptoms and resolution of the lesion as revealed by repeat magnetic resonance imaging. CONCLUSION: Presentation of a pons abscess with trigeminal neuralgia is rare, and to the best of our knowledge has not been reported previously. The patient was treated successfully with antibiotics alone.

Abscess↗

Clinical importance of ligamentous and osseous structures in the cervical uncovertebral foraminal region.

The vertebral artery, cervical spinal nerves, spinal nerve roots, and the bony and ligamentous tissue related to the cervical vertebrae are structures whose anatomy determines the path of a surgical approach. Defining the anatomy and, in particular, determining the precise location of vulnerable structures at the intervertebral foramen and the uncovertebral foraminal region (UVFR), a region defined by the uncinate process anteriorly, the facet joint posteriorly and the foramen transversarium laterally, has critical significance when selecting the safest surgical approach. We studied the anatomy of the vertebral artery, cervical spinal nerves, and spinal nerve roots within the UVFR in six cadaver specimens. We also obtained measurements of bony structures in 35 dry cervical vertebral columns, from C3-C7. The uncinate process (UP) projects superiorly from the posterolateral aspect of each cervical vertebral body, except for the first and second vertebrae. Because the posterior part of the UP lies adjacent to the vertebral artery, spinal nerve, and spinal nerve roots, its resection creates sufficient space to decompress these structures directly. The posterolateral surface of the UP is covered by ligamentous tissue that originates from the posterior longitudinal ligament and protects the neural and vascular structures during their decompression in the UVFR.

Cervical Vertebrae↗

Chance type cervical fracture and neurological deficits in ankylosing spondylitis.

Prevention of sudden neck movements is vital in patients with ankylosing spondylitis of the cervical spine. We present a case of ankylosing spondylitis who sustained a cervical fracture. He presented with paraplegia after a minor car collision and died of pulmonary embolism after the operation for anterior stabilisation. We believe that the most important matter in a patient with advanced ankylosing spondylitis is the prevention of the fractures and complications. The need for neck protection in automobiles was emphasized and the literature reviewed about the occurrences of neurological deficits following trauma.

Accidents, Traffic↗