Taner Tanriverdi

Long-term seizure outcome after mesial temporal lobe epilepsy surgery: corticalamygdalohippocampectomy versus selective amygdalohippocampectomy

OBJECT Resection strategies for the treatment of temporal lobe epilepsy (TLE) are a matter of discussion, and little information is available. The aim of this study was to compare seizure outcomes at the 5-year follow-up in patients with medically refractory unilateral mesial TLE (MTLE) due to hippocampal sclerosis (HS) who were treated using a cortical amygdalohippocampectomy (CorAH) or a selective AH (SelAH). METHODS The authors obtained data from 100 adult patients who underwent surgery for MTLE. Fifty patients underwent a CorAH and 50 underwent an SelAH. Seizure control achieved with each technique was compared using the Engel classification scheme. RESULTS Overall, at the 5-year follow-up, favorable (Engel Classes I and II) seizure outcomes were noted in 82 and 90% of patients who had undergone CorAH and SelAH, respectively. Furthermore, 40% of the patients who had undergone a CorAH and 58% of those who had undergone an SelAH were seizure free (Engel Class Ia). There was no statistically significant difference between the 2 surgical approaches in terms of seizure outcome at the 5-year follow-up (p = 0.38). CONCLUSIONS Both CorAH and SelAH can lead to similar favorable seizure control in patients with MTLE/HS. However, the authors suggest that the transcortical selective approach has the great advantage of minimizing or completely abolishing the impact of dividing several venous and arterial adhesions which are tedious, time consuming, and, at times, associated with some degree of cerebral swelling.

Long-term seizure outcome after corpus callosotomy: a retrospective analysis of 95 patients.

OBJECT The authors report long-term follow-up seizure outcome in patients who underwent corpus callosotomy during the period 1981-2001 at the Montreal Neurological Institute. METHODS The records of 95 patients with a minimum follow-up of 5 years (mean 17.2 years) were retrospectively evaluated with respect to seizure, medication outcomes, and prognostic factors on seizure outcome. RESULTS All patients had more than one type of seizure, most frequently drop attacks and generalized tonic-clonic seizures. The most disabling seizure type was drop attacks, followed by generalized tonic-clonic seizures. Improvement was noted in several seizure types and was most likely for generalized tonic-clonic seizures (77.3%) and drop attacks (77.2%). Simple partial, generalized tonic, and myoclonic seizures also benefited from anterior callosotomy. The extent of the callosal section was correlated with favorable seizure outcome. The complications were mild and transient and no death was seen. CONCLUSIONS This study confirms that anterior callosotomy is an effective treatment in intractable generalized seizures that are not amenable to focal resection. When considering this procedure, the treating physician must thoroughly assess the expected benefits, limitations, likelihood of residual seizures, and the risks, and explain them to the patient, his or her family, and other caregivers.

Memory outcome after temporal lobe epilepsy surgery: corticoamygdalohippocampectomy versus selective amygdalohippocampectomy

OBJECT The aim of this study was to compare IQ and memory outcomes at the 1-year follow-up in patients with medically refractory mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis. All patients were treated using a corticoamygdalohippocampectomy (CAH) or a selective amygdalohippocampectomy (SelAH). METHODS The data of 256 patients who underwent surgery for MTLE were retrospectively evaluated. One hundred twenty-three patients underwent a CAH (63 [right side] and 60 [left side]), and 133 underwent an SelAH (61 [right side] and 72 [left side]). A comprehensive neuropsychological test battery was assessed before and 1 year after surgery, and the results were compared between the surgical procedures. Furthermore, seizure outcome was compared using the Engel classification scheme. RESULTS At 1-year follow-up, there was no statistically significant difference between the surgical approaches with respect to seizure outcome. Overall, IQ scores showed improvement, but verbal IQ decreased after left SelAH. Verbal memory impairment was seen after left-sided resections especially in cases of SelAH, and nonverbal memory decreased after right-sided resection, especially for CAH. Left-sided resections produced some improvement in nonverbal memory. Older age at surgery, longer duration of seizures, greater seizure frequency before surgery, and poor seizure control after surgery were associated with poorer memory. CONCLUSIONS Both CAH and SelAH can lead to several cognitive impairments depending on the side of the surgery. The authors suggest that the optimal type of surgical approach should be decided on a case-by-case basis.

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.

Cerebrospinal fluid superoxide dismutase and serum malondialdehyde levels in patients with aneurysmal subarachnoid hemorrhage : preliminary results

Abstract Objectives: Experimental studies provide evidence that oxidative damage plays a role in the development of vasospasm after aneurysmal subarachnoid hemorrhage (SAH) but data from human studies is still limited. The purpose of this study was to investigate the time course of cerebrospinal fluid (CSF) superoxide dismutase (SOD) and serum malondialdehyde (MDA) changes in patients with aneurysmal SAH. Methods: SOD in CSF and MDA in the serum were detected on days 1–3, 5 and 7 after aneurysmal SAH in 21 patients, and the results were compared with 15 patients with hydrocephalus. The results were also compared with those of clinical parameters including the patients outcome at 6 months. Results: The mean CSF SOD levels were lower and serum MDA levels were higher than the controls. Patients with a high amount of blood within the cisterns had a trend to decreased SOD while increasing MDA levels. Conclusion: These preliminary results suggest that the levels of antioxidants are decreased after the onset of SAH in the early period, possibly because of increased oxidative stress. Reactive oxygen-mediated oxidative damage may play an important role in inflammation after SAH.

Catabolic cytokine expressions in patients with degenerative disc disease.

AIM Lumbar degenerative disc disease (DDD) is a common disease of advanced age characterized by progressive changes in the intervertebral disc and associated structures. There have been great efforts for years to explain its pathophysiological mechanism(s). This study aims to provide cytokine profile and in addition to the lymphocytes in a population of patients with lumbar DDD. MATERIAL AND METHODS Twenty-six patients whose clinical and radiological features were suggestive of lumbar DDD that underwent surgery and 14 autopsy cases as control were included. Patient disc samples were obtained during surgery whilst disc materials were collected during autopsy procedures from the controls. Major cytokines and lymphocytes were studied by using the flow cytometry method. RESULTS Significantly higher levels in disc samples in relation to IL-1β, IL-2, IL-4, IL-10, IL-12, TNF-α, CD8, CD56, CD19, and CD40 were found in the patients compared to the controls. Positive correlations were shown between CD3/CD4, CD25/CD3, CD25/CD4, CD19/CD4 but negative correlations were shown between CD19/CD3 and CD25/CD19 in both groups. CONCLUSION The findings suggest that both local inflammatory responses occur in lumbar DDD. Using specific cytokines either by local or systemic application may reverse the degenerative process.

Tractography of the amygdala and hippocampus: anatomical study and application to selective amygdalohippocampectomy.

OBJECT The aim of this study was to evaluate, using diffusion tensor tractography, the white matter fibers crossing the hippocampus and the amygdala, and to perform a volumetric analysis and an anatomical study of the connections of these 2 structures. As a second step, the authors studied the white matter tracts crossing a virtual volume of resection corresponding to a selective amygdalohippocampectomy. METHODS Twenty healthy right-handed individuals underwent 3-T MR imaging. Volumetric regions of interest were manually created to delineate the amygdala, the hippocampus, and the volume of resection. White matter fiber tracts were parcellated using the fiber assignment for continuous tracking tractography algorithm. All fibers were registered with the anatomical volumes. RESULTS In all participants, the authors identified fibers following the hippocampus toward the fornix, the splenium of the corpus callosum, and the dorsal hippocampal commissure. With respect to the fibers crossing the amygdala, the authors identified the stria terminalis and the uncinate fasciculus. The virtual resection disrupted part of the fornix, fibers connecting the 2 hippocampi, and fibers joining the orbitofrontal cortex. The approach created a theoretical frontotemporal disconnection and also interrupted fibers joining the temporal pole and the occipital area. CONCLUSIONS This diffusion tensor tractography study allowed for good visualization of some of the connections of the amygdala and hippocampus. The authors observed that the virtual selective amygdalohippocampectomy disconnected a large number of fibers connecting frontal, temporal, and occipital areas.