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Lobe Resection (lobe + resection)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Lobe Resection

  • temporal lobe resection
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    Selected Abstracts

    Functional MRI Predicts Memory Performance after Right Mesiotemporal Epilepsy Surgery

    EPILEPSIA, Issue 2 2005
    Jozsef Janszky
    Summary:,Purpose: Anterior temporal lobe resection (ATR) is a treatment option in drug-resistant epilepsy. An important risk of ATR is loss of memory because mesiotemporal structures contribute substantially to memory function. We investigated whether memory-activated functional MRI (fMRI) can predict postoperative memory loss after anterior temporal lobectomy in right-sided medial temporal lobe epilepsy (MTLE). Methods: We included 16 patients (10 women) aged 16,54 years. The mean age at epilepsy onset was 12.5 years (range, 1,26 years). The patients' mean Wechsler IQ score was 95.2 (range, 62,125). The activation condition of fMRI consisted of retrieval from long-term memory induced by self-paced performance of an imaginative walk. All but one patient had left-sided speech dominance according to speech-activated fMRI. Outside the scanner, we evaluated the pre- and postoperative visual memory retention by using Rey Visual Design Learning Test. Results: We found a correlation between the preoperative asymmetry index of memory- fMRI and the change between pre- and postsurgical measures of memory retention. Reduced activation of the mesiotemporal region ipsilateral to the epileptogenic region correlated with a favorable memory outcome after right-sided ATR. Conclusions: In light of the postoperative results, the theoretical implication of our study is that fMRI based on a simple introspective retrieval task measures memory functions. The main clinical implication of our study is that memory- fMRI might replace the invasive Wada test in MTLE by using a simple fMRI paradigm. Predictive power, however, will be studied in larger patient samples. Other studies are required for left-sided MTLE and neocortical epilepsies to assess the clinical usefulness of memory- fMRI. [source]

    Wada Memory Performance Predicts Seizure Outcome after Epilepsy Surgery in Children

    EPILEPSIA, Issue 7 2003
    Gregory P. Lee
    Summary: Purpose: Wada memory asymmetries were examined in children from four comprehensive epilepsy surgery centers who subsequently underwent epilepsy surgery to determine whether Wada memory performance could predict degree of seizure relief in children. Methods: One hundred fifty-six children (between ages 5 and 16 years) with intractable epilepsy underwent Wada testing before resective epilepsy surgery (93 within the left hemisphere, and 63 within the right hemisphere). Memory stimuli were presented soon after intracarotid amobarbital injection, and recognition memory for the items was assessed after return to neurologic baseline. Eighty-eight children underwent unilateral temporal lobe resection, and 68 had extratemporal lobe resections. One hundred four (67%) children were seizure free (Engel class I), and 52 (33%) were not seizure free (Engel classes II,IV) at follow-up (mean follow-up interval, 2.3 years). Results: Seizure-free children recalled 19.3% more Wada memory items after ipsilateral injection than did non,seizure-free children (p = 0.008). If analysis was restricted to youngsters with temporal lobectomies (TLs), seizure-free children recalled 27.7% more items after ipsilateral injection than did non,seizure-free TL children (p = 0.004). With regard to individual patient prediction, 75% of children who had memory score asymmetries consistent with the seizure focus were seizure free. In contrast, only 56% of children whose memory score asymmetries were inconsistent with the seizure focus were seizure free (p = 0.01). Conclusions: Results suggest that Wada memory performance asymmetries are related to the degree of seizure relief after epilepsy surgery in children and adolescents. [source]

    Efficient hepatocyte engraftment and long-term transgene expression after reversible portal embolization in nonhuman primates,

    HEPATOLOGY, Issue 3 2009
    Ibrahim Dagher
    The feasibility of ex vivo gene therapy as an alternative to liver transplantation for the treatment of liver metabolic diseases needs to be analyzed in large animal models. This approach requires appropriate gene transfer vectors and effective hepatocyte engraftment. Lentiviral vectors have the ability to transduce nondividing differentiated cells, such as hepatocytes, and portal vein occlusion increases hepatocyte engraftment. We investigated whether reversible portal vein embolization combined with ex vivo lentivirus-mediated gene transfer is an effective approach for successful hepatocyte engraftment in nonhuman primates and whether the transgene remains expressed in the long term in transplanted hepatocytes in situ. Simian hepatocytes were isolated after left lobe resection, and the left and right anterior portal branches of animals were embolized with absorbable material. Isolated hepatocytes were labeled with Hoechst dye or transduced in suspension with lentiviruses expressing green fluorescent protein under the control of the human apolipoprotein A-II promoter and transplanted via the inferior mesenteric vein. The whole procedure was well tolerated. The embolized liver was revascularized within 2 weeks. The volume of nonembolized liver increased from 38.7% ± 0.8% before embolization to 55.9% ± 1% after embolization and hepatocytes significantly proliferated (10.5% ± 0.4% on day 3 after embolization). Liver repopulation after transplantation with Hoechst-labeled hepatocytes was 7.4% ± 1.2%. Liver repopulation was 2.1% ± 0.2% with transduced hepatocytes, a proportion similar to that obtained with Hoechst-labeled cells, given that the mean transduction efficacy of simian hepatocyte population was 34%. Transgene expression persisted at 16 weeks after transplantation. Conclusion: We have developed a new approach to improve hepatocyte engraftment and to express a transgene in the long term in nonhuman primates. This strategy could be suitable for clinical applications. (HEPATOLOGY 2009.) [source]

    Magnetic Resonance Analysis of Postsurgical Temporal Lobectomy

    JOURNAL OF NEUROIMAGING, Issue 3 2001
    Taoufik M. Alsaadi MD
    ABSTRACT Background and Purpose. The effect of temporal lobe transection area, volume of postoperative gliosis, and surgical technique on patients' seizure-free outcome is unknown. The authors studied the effects of these variables on patients' seizure-free outcome. Methods. A retrospective review of magnetic resonance imaging examinations acquired 3 to 18 months after temporal lobe resection was carried out for 18 patients with intractable temporal lobe seizures and known postsurgical outcomes for more than 2 years. The total volume of radiologically probable gliosis evident on axial proton-density-weighted images was calculated for each patient using software on an independent console. The total area of temporal lobe surface transected by the scalpel was calculated as well, using sagittal T1-weighted images. The total volume of gliosis, the total area of transected temporal lobe, and the specific type of surgery (sparing vs no sparing of the superior temporal gyrus) were then correlated with the postsurgical outcome of the patients. An examiner with no prior knowledge of the patients' postsurgical outcomes carried out the above calculations and measurements. The patients' postoperative outcome was defined using Engel classifications, and patients were divided into two groups: group A with Engel class 1 (n= 9) and group B with Engel classes 2,4 (n= 9). Results. The mean volumes of postoperative gliosis were not significantly different between group A (3592.3 mm3) and group B (4270 mm3). The mean area of transected temporal lobe was also similar between group A (1865.2 mm2) and group B (1930 mm2). With regard to surgical technique, there were 5 subjects who had the superior temporal gyrus resected and 13 who did not. Eighty percent of patients with the superior temporal gyrus resected were Engel class 1 or 2, whereas only 20% were of Engel class 3 or 4. Conclusion. The authors found no clear association between postoperative outcome and residual temporal lobe gliosis, the surgical technique, or the total area of temporal lobe transected by the scalpel. [source]

    Wada Memory Performance Predicts Seizure Outcome after Epilepsy Surgery in Children

    EPILEPSIA, Issue 7 2003
    Gregory P. Lee
    Summary: Purpose: Wada memory asymmetries were examined in children from four comprehensive epilepsy surgery centers who subsequently underwent epilepsy surgery to determine whether Wada memory performance could predict degree of seizure relief in children. Methods: One hundred fifty-six children (between ages 5 and 16 years) with intractable epilepsy underwent Wada testing before resective epilepsy surgery (93 within the left hemisphere, and 63 within the right hemisphere). Memory stimuli were presented soon after intracarotid amobarbital injection, and recognition memory for the items was assessed after return to neurologic baseline. Eighty-eight children underwent unilateral temporal lobe resection, and 68 had extratemporal lobe resections. One hundred four (67%) children were seizure free (Engel class I), and 52 (33%) were not seizure free (Engel classes II,IV) at follow-up (mean follow-up interval, 2.3 years). Results: Seizure-free children recalled 19.3% more Wada memory items after ipsilateral injection than did non,seizure-free children (p = 0.008). If analysis was restricted to youngsters with temporal lobectomies (TLs), seizure-free children recalled 27.7% more items after ipsilateral injection than did non,seizure-free TL children (p = 0.004). With regard to individual patient prediction, 75% of children who had memory score asymmetries consistent with the seizure focus were seizure free. In contrast, only 56% of children whose memory score asymmetries were inconsistent with the seizure focus were seizure free (p = 0.01). Conclusions: Results suggest that Wada memory performance asymmetries are related to the degree of seizure relief after epilepsy surgery in children and adolescents. [source]

    Parenchymal lesions in pharmacoresistant temporal lobe epilepsy: dual and multiple pathology

    ACTA NEUROLOGICA SCANDINAVICA, Issue 3 2005
    S. H. Eriksson
    Objectives,,, Dual pathology is reported in 5,30% of temporal lobe resections performed in pharmacoresistant epilepsy. Dual pathology may be of importance for surgical planning and also for the understanding of the pathogenesis of epilepsy. We describe the frequency of dual or multiple pathology, i.e. more than one histopathological diagnosis, in adults with temporal lobe resections. Material and Methods,,, Surgical specimens from 33 consecutive patients with resections including mesial as well as neocortical temporal structures were reviewed. All histopathological findings were recorded. Post-mortem specimens from 11 control subjects were also reviewed. Results,,, Dual or multiple pathology was found in almost half of the epilepsy patients (48%). Hippocampal sclerosis was found in 25 patients (76%), malformations of cortical development in 15 (46%), of which 12 (36%) were microdysgenesis, and low-grade tumours in seven (21%). Apart from mild gliosis, there were no histopathological changes in the control specimens. Conclusion,,, Dual or multiple pathology was a common finding in this group of adults with temporal lobe resections. In order to increase our understanding of how aetiological factors may combine in the development of seizures, we consider it relevant and important to report all histopathological findings in epilepsy surgery series. [source]