Galip Zihni Sanus

Cranioplasty: Review of materials and techniques.

Cranioplasty is the surgical intervention to repair cranial defects. The aim of cranioplasty is not only a cosmetic issue; also, the repair of cranial defects gives relief to psychological drawbacks and increases the social performances. Many different types of materials were used throughout the history of cranioplasty. With the evolving biomedical technology, new materials are available to be used by the surgeons. Although many different materials and techniques had been described, there is still no consensus about the best material, and ongoing researches on both biologic and nonbiologic substitutions continue aiming to develop the ideal reconstruction materials. In this article, the principle materials and techniques of cranioplasty are reviewed.

Intrathecal Gadolinium-Enhanced MR Cisternography in the Evaluation of CSF Leakage

BACKROUND AND PURPOSE: Radiologic identification of the location of the CSF leakage is important for proper surgical planning and increases the chance of dural repair. This article describes our experience in analyzing clinically suspected cranial CSF fistulas by using MR imaging combined with the intrathecal administration of a gadolinium-based contrast agent. MATERIALS AND METHODS: A total of 85 consecutive patients with suspected CSF fistulas who presented with persistent or intermittent rhinorrhea or otorrhea lasting for more than 1 month between 2003 and 2007 were included in this study. RESULTS: We observed objective CSF leakage in 64 of 85 patients (75%). The CSF leak was located in the ethmoidal region in 37 patients (58%), in the superior wall of the sphenoid sinus in 8 patients (13%), in the posterior wall of the frontal sinus in 10 patients (15%), in the superior wall of the mastoid air cells in 6 patients (9%), and from the skull base into the infratemporal fossa in 1 patient (2%). Two patients (3%) showed leakage into >1 paranasal sinus. CONCLUSIONS: MR cisternography after the intrathecal administration of gadopentate dimeglumine represents an effective and minimally invasive method for evaluating suspected CSF fistulas along the skull base. It provides multiplanar capabilities without risk of radiation exposure and is an excellent approach to depict the anatomy of CSF spaces and CSF fistulas.

Acute ethanol intoxication in a model of traumatic brain injury: the protective role of moderate doses demonstrated by immunoreactivity of synaptophysin in hippocampal neurons.

Abstract Although ethanol intoxication is reported to be a complicating factor in traumatic brain injury, some recent studies are indicating its possible protective role especially at lower doses. Ethanol inhibition of NMDA-mediated excitotoxicity which predominates at lower doses is believed to be responsible for this protection. The aim of this study was to demonstrate this neuroprotective role of alcohol using immunoreactivity for synaptophysin as an indirect marker for severity of injury. Acute ethanol intoxication at moderate doses was performed 2 h prior to trauma. Severe traumatic brain injury was administrated using an impact acceleration model in Sprague–Dawley rats. At post-traumatic 48th hour, immunorectivity for synapthophysin in the rat hippocampi was evaluated under light microscopy. According to our results there were slight increases in immunoreactivity for synaptophysin in the stratum oriens and striatum radiatum of CA1 subfield of hippocampus when ethanol was administered prior to trauma comparing to moderate increase in the trauma-only group. On the other hand vacuolar degeneration and red neuron formation was more prominent in the pyramidal cell layer of CA1 and CA3 when ethanol was not administered. Ethanol may have a neuroprotective role when administered at moderate doses prior to traumatic brain injury. This effect of ethanol may primarily be due to inhibition of NMDA receptors.

Expression and cellular distribution of multidrug resistance-related proteins in patients with focal cortical dysplasia

Recent arouse of interest indicated that drug resistant proteins are markedly over-expressed in the epileptogenic tissue and they may be responsible for the one-third of the epileptic patients who were refractory to anti-epileptic drugs (AEDs). Since several AEDs may act as substrates for these drug resistant proteins, the enhanced function of such proteins may increase drug extrusion, resulting in inadequate response to drug therapy in patients with epilepsy. We studied expression of the multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1) in the epileptic tissues resected surgically in 28 patients with focal cortical dysplasia (FCD) by immunohistochemistry. The results were compared with 10 normal necropsy brain tissues. Normal brain showed no MDR1 expression in neurons and astrocytes, while MRP1 expression was very weak, which were encountered in a few samples. MDR1 expression was mainly localized on the vascular endothelial cells. In contrast to normal brain, we found intense MDR1 and MRP1 expression in both neurons and reactive astrocytes in the vast majority of dysplastic tissues. The majority of the dysplastic neurons demonstrated moderate to strong MRP1 immunoreactivity. Endothelial cells showed both MDR1 and MRP1 expression in the majority of the specimens studied. Multidrug transporters are over-expressed in the epileptogenic zone in patients with FCD. These results are concordant with previous studies, in which over-expression of multidrug proteins were shown in epileptogenic brain tissue in patients with FCD, that the over-expression of drug transport proteins in tissue from patients with refractory epilepsy may explain one possible mechanism for drug resistant in these pathologies.

Evaluation of apoptosis in cerebrospinal fluid of patients with severe head injury

SummaryObjective. To determine whether sFas, caspase-3, proteins which propagate apoptosis, and bcl-2, a protein which inhibits apoptosis, would be increased in cerebrospinal fluid (CSF) in patients with severe traumatic brain injury (TBI) and to examine the correlation of sFas, caspase-3, and bcl-2 with each other and with clinical variables. Methods. sFas, caspase-3, and bcl-2 were measured in CSF of 14 patients with severe TBI on days 1, 2, 3, 5, 7, and 10 post-trauma. The results were compared with CSF samples from control patients who had no brain and spinal pathology and had undergone spinal anesthesia for some other reason. Soluble Fas and bcl-2 were measured by ELISA while caspase-3 was measured enzymatically. Results. No sFas, caspase-3, and bcl-2 activities were found in CSF of controls, but activities significantly increased in CSF of patients at all time points post-trauma (p < 0.01). Caspase-3 significantly correlated to intracranial pressure (p = 0.01) and cerebral perfusion pressure (p = 0.04). Soluble Fas and caspase-3 peaks coincided on day 5 post-trauma and there was significant association between sFas and caspase-3 increase (p = 0.01). Conclusion. This study indicates a prolonged activation of pro-apoptotic (sFas, caspase-3) and anti-apoptotic (bcl-2) proteins after severe TBI in humans. The degree of activation of particularly caspase-3 may be related to the severity of the injury. Parallel increases of these three molecules may indicate a pivotal role of apoptosis in the pathophysiology of post-traumatic brain oedema, secondary cell destruction and chronic cell loss following severe TBI and may open new targets for post-traumatic therapeutic interventions.

Association between interleukin-1 beta (IL-1β) gene polymorphism and outcome after head injury: an early report

SummaryBackground. Recent studies focusing on the genetic influences on outcome after head injury (HI) have suggested that different alleles of certain genes are associated with different outcomes. Interleukin-1 beta (IL-1β) gene, especially β2 polymorphism, is frequently observed in Alzheimer’s disease, a remarkable degenerative state in which HI is among the known risk factors. Therefore, the aim of this paper was to search for the possible association between the outcome and IL-1β gene polymorphism in human HI.Methods. The study group was composed of the 69 patients admitted to the neurosurgery department after HI. The severity of the initial injury was evaluated by means of the Glasgow Coma Scale and outcome six months later was assessed by means of the Glasgow Outcome Scale. IL-1β genotypes were determined from blood samples by standard methods.Findings. Fourteen of 25 (56%) patients with IL-1β +3953 allele 2 had an unfavourable outcome (dead, vegetative state or severe disability) compared with eight of 44 (18.1%) patients without IL-1β +3953 (p = 0.0004). Similarly, 20 of 28 (71.4%) patients with IL-1β −511 allele 2 had an unfavourable outcome compared with two of 41 (4.8%) patients without IL-1β −511 (p = 0.005). Patients who had a composite of IL-1β 2/2 or 1/2 genotype from both −511 and +3953 region of the chromosome 2 were more prone to have bad prognosis.Conclusion. Results of our study demonstrated that there might be a significant association between IL-1β gene polymorphism and outcome after HI, supporting the hypothesis of a genetically determined influence.

Middle fossa approach: microsurgical anatomy and surgical technique from the neurosurgical perspective

BACKGROUND The purpose of this study was to call attention to the subtemporal approach directed through the petrous apex to the IAM. We studied the microsurgical anatomy of the middle floor to delineate a reliable angle between the GSPN and the IAM to precisely localize and expose the IAM from above. A new technique for the elevation of middle fossa floor in an anterior-to-posterior direction has also been examined in cadaveric dissections and performed in surgery. METHODS The microsurgical anatomy of the middle fossa floor was studied in 10 adult cadaveric heads (20 sides) after meatal drilling on the middle fossa. Five latex-injected specimens were dissected in a stepwise manner to further define the microsurgical anatomy of the middle fossa approach. The middle fossa approach is illustrated in a patient for the decompression of the facial nerve to demonstrate the surgical technique and limitations of bone removal. RESULTS Elevation of middle fossa dura in an anterior-to-posterior direction leads to early identification of the GSPN, where the nerve passes under V3. The most reliable and easily appreciated angle to be used in localizing the IAM is between the IAM and the long axis of the GSPN, which is approximately 61 degrees . Beginning drilling the meatus medially at the petrous ridge is safer than beginning laterally, where the facial and vestibulocochlear nerves become more superficial. The cochlea anteromedially, vestibule posterolaterally, and superior semicircular canal posteriorly significantly limit the bone removal at the lateral part of the IAM. CONCLUSIONS The surgical technique for the middle fossa approach which includes an anterior-to-posterior elevation of middle fossa dura starting from the foramen ovale and uses the angle between the IAM and the long axis of the GSPN to localize the meatus from above may be an alternative to previously proposed surgical methods.

Use of Cortoss as an alternative material in calvarial defects: the first clinical results in cranioplasty.

A clinical series of 13 patients who underwent cranioplasty using a new quick setting material, namely Cortoss™ was done over 3-year period. Thus, the primary objective of this study is to evaluate the role of Cortoss™ in the treatment calvarial defects which were mainly due to trauma (4 patients), tumor or tumor-like lesions (5 patients), middle cerebral infarction (3 patients), and gun shot wound (1 patient). The surgical technique was found to be simple and effective. Long-term follow-up (mean 24.3 months) demonstrated satisfactory results in terms of surgical (functional) and cosmetic outcomes. None of the patients developed complications including infections, foreign body reactions or material leakage. The results led us to suggest that the use of Cortoss™ in the case of calvarial defects seems to be safe, effective, quick, and a feasible method for cranioplasty. We conclude that the mechanical, immunologic, and technical-grafting properties of Cortoss™, together with its superior esthetic and psychological effects, probably will make it the best material for cranioplasty.

Expression of hypoxia inducible factor-1α in tumors of patients with glioblastoma multiforme and transitional meningioma

Hypoxia-inducible factor-1 alpha (HIF-1alpha) is the major transcriptional factor involved in the adaptive response to hypoxia. The aim of this study was to assess HIF-1alpha in 22 patients with transitional meningioma (TM) and 26 patients with glioblastoma multiforme (GBM). HIF-1alpha was assessed using a commercially available enzyme-linked immunosorbent assay-based HIF-1 transcription factor assay. Levels of HIF-1alpha in TM and GBM were measured using optical density at 450nm, and median values were found to be 0.35 for TM and 0.37 OD for GBM, respectively. There was no statistically significant difference between the two types of tumor (p=0.264). These findings indicate that HIF-1alpha is elevated in both TM and GBM, suggesting that although hypoxia is one of the most important and powerful stimuli for HIF-1alpha elevation and consequently angiogenesis, other mechanisms may play roles in HIF-1alpha stimulation in benign brain tumors such as TM.

Evolving Traumatic Brain Lesions: Predictors and Results of Ninety-Eight Head-Injured Patients

Progression in intracranial lesion(s) caused by traumatic brain injuries may be determined by a serial computerized tomography (CT) scan in the early period, but its significance is still controversial. In this study, the records of 98 head-injured patients in whom 2 consecutive CT scans were performed within 48 hours of injury were analyzed, and the predictors and clinical significance of progressive hemorrhagic injury (PHI) were determined. From June 1, 1998 through July 13, 2002, a cohort of 98 head-injured patients (65 male and 33 female, mean age of 34.8 years, and median Glasgow Come Scale [GCS] score of 11) was evaluated in this retrospective clinical study. The patients were divided into 2 groups: groups 1 and 2 included 51 and 47 patients without and with PHI, respectively. Progression in traumatic lesion(s) was determined by comparing the initial and repeated CT scans. Logistic regression analysis was used to identify physiologic parameters (P = 0.02), Injury Severity Score (P = 0.01), increased intracranial pressure (P = 0.005), and initial diagnosis (P = 0.01) as the best predictors of PHI. The 6-month postinjury outcome was favorable in group 1. PHI occurs mostly in intracerebral hematomas, which are associated with an increase in ICP. Age, increase in ICP, type of initial lesion(s), ISS, anemia, hypoxia, hyperglycemia, coagulopathy, and timing of the first CT scan relative to injury seem to be predictors of PHI.