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Glenn D Rosen - One of the best experts on this subject based on the ideXlab platform.
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effects of test experience and neocortical microgyria on spatial and non spatial learning in rats
Behavioural Brain Research, 2012Co-Authors: Steven W Threlkeld, Glenn D Rosen, Caitlin E Szalkowski, Dongnhu T Truong, C A St Hill, Holly R FitchAbstract:Neocortical neuronal migration anomalies such as microgyria and heterotopia have been associated with developmental language learning impairments in humans, and rapid auditory processing deficits in rodent models. Similar processing impairments have been suggested to play a causal role in human language impairment. Recent data from our group has shown spatial working memory deficits associated with neocortical microgyria in rats. Similar deficits have also been identified in humans with language learning impairments. To further explore the extent of learning deficits associated with cortical neuronal migration anomalies, we evaluated the effects of neocortical microgyria and test order experience using spatial (Morris water maze) and non-spatial water maze learning paradigms. Two independent groups were employed (G1 or G2) incorporating both microgyria and sham conditions. G1 received spatial testing for five days followed by non-spatial testing, while the reverse order was followed for G2. Initial analysis, including both test groups and both maze conditions, revealed a main effect of treatment, with microgyric rats performing significantly worse than shams. Overall analysis also revealed a task by order interaction, indicating that each group performed better on the second task as compared to the first, regardless of which task was presented first. Independent analyses of each task revealed a significant effect of treatment (microgyria worse than sham) only for the spatial water maze condition. Results indicate that prior maze experience (regardless of task type) leads to better subsequent performance. Results suggest that behavioral abnormalities associated with microgyria extend beyond auditory and working memory deficits seen in previous studies, to include spatial but not non-spatial learning impairments and that non-specific test experience may improve behavioral performance.
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low power photomicrograph of a wistar rat brain with bilateral microgyria arrows
2011Co-Authors: Ann M Peiffer, Holly R Fitch, Jennifer J Thomas, Alexandra Nicole Yurkovic, Glenn D RosenAbstract:Copyright information: Taken from "Brain weight differences associated with induced focal microgyria"BMC Neuroscience 2003;4():12-12.Published online 24 Jun 2003http://www.ncbi.nlm.nih.gov/pmc/articles/PMC166148.Copyright © 2003 Peiffer et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL. Note the normal-appearing cortex medial and lateral to the microgyria. Bar = 800 μm.
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early acoustic discrimination experience ameliorates auditory processing deficits in male rats with cortical developmental disruption
International Journal of Developmental Neuroscience, 2009Co-Authors: Steven W Threlkeld, Glenn D Rosen, C A St Hill, Holly R FitchAbstract:Abstract Auditory temporal processing deficits have been suggested to play a causal role in language learning impairments, and evidence of cortical developmental anomalies (microgyria (MG), ectopia) has been reported for language-impaired populations. Rodent models have linked these features, by showing deficits in auditory temporal discrimination for rats with neuronal migration anomalies (MG, ectopia). Since evidence from human studies suggests that training with both speech and non-speech acoustic stimuli may improve language performance in developmentally language-disabled populations, we were interested in whether/how maturation and early experience might influence auditory processing deficits seen in male rats with induced focal cortical MG. Results showed that for both simple (Normal single tone), as well as increasingly complex auditory discrimination tasks (silent gap in white noise and FM sweep), prior experience significantly improved acoustic discrimination performance—in fact, beyond improvements seen with maturation only. Further, we replicated evidence that young adult rats with MG were significantly impaired at discriminating FM sweeps compared to shams. However, these MG effects were no longer seen when experienced subjects were retested in adulthood (even though deficits in short duration FM sweep detection were seen for adult MG rats with no early experience). Thus while some improvements in auditory processing were seen with normal maturation, the effects of early experience were even more profound, in fact resulting in amelioration of MG effects seen at earlier ages. These findings support the clinical view that early training intervention with appropriate acoustic stimuli could similarly ameliorate long-term processing impairments seen in some language-impaired children.
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persistent spatial working memory deficits in rats with bilateral cortical microgyria
Behavioral and Brain Functions, 2008Co-Authors: Holly R Fitch, Glenn D Rosen, Heather Breslawski, James J ChrobakAbstract:Background: Anomalies of cortical neuronal migration (e.g., microgyria (MG) and/or ectopias) are associated with a variety of language and cognitive deficits in human populations. In rodents, postnatal focal freezing lesions lead to the formation of cortical microgyria similar to those seen in human dyslexic brains, and also cause subsequent deficits in rapid auditory processing similar to those reported in human language impaired populations. Thus convergent findings support the ongoing study of disruptions in neuronal migration in rats as a putative model to provide insight on human language disability. Since deficits in working memory using both verbal and non-verbal tasks also characterize dyslexic populations, the present study examined the effects of neonatally induced bilateral cortical microgyria (MG) on working memory in adult male rats. Methods: A delayed match-to-sample radial water maze task, in which the goal arm was altered among eight locations on a daily basis, was used to assess working memory performance in MG (n = 8) and sham (n = 10) littermates. Results: Over a period of 60 sessions of testing (each session comprising one pre-delay sample trial, and one post-delay test trial), all rats showed learning as evidenced by a significant decrease in overall test errors. However, MG rats made significantly more errors than shams during initial testing, and this memory deficit was still evident after 60 days (12 weeks) of testing. Analyses performed on daily error patterns showed that over the course of testing, MG rats utilized a strategy similar to shams (but with less effectiveness, as indicated by more errors). Conclusion: These results indicate persistent abnormalities in the spatial working memory system in rats with induced disruptions of neocortical neuronal migration.
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developmental timeframes for induction of microgyria and rapid auditory processing deficits in the rat
Brain Research, 2006Co-Authors: Steven W Threlkeld, Glenn D Rosen, Melissa M Mcclure, Holly R FitchAbstract:Abstract Induction of a focal freeze lesion to the skullcap of a 1-day-old rat pup leads to the formation of microgyria similar to those identified postmortem in human dyslexics. Rats with microgyria exhibit rapid auditory processing deficits similar to those seen in language-impaired (LI) children, and infants at risk for LI and these effects are particularly marked in juvenile as compared to adult subjects. In the current study, a startle response paradigm was used to investigate gap detection in juvenile and adult rats that received bilateral freezing lesions or sham surgery on postnatal day (P) 1, 3 or 5. Microgyria were confirmed in P1 and 3 lesion rats, but not in the P5 lesion group. We found a significant reduction in brain weight and neocortical volume in P1 and 3 lesioned brains relative to shams. Juvenile (P27–39) behavioral data indicated significant rapid auditory processing deficits in all three lesion groups as compared to sham subjects, while adult (P60+) data revealed a persistent disparity only between P1-lesioned rats and shams. Combined results suggest that generalized pathology affecting neocortical development is responsible for the presence of rapid auditory processing deficits, rather than factors specific to the formation of microgyria per se. Finally, results show that the window for the induction of rapid auditory processing deficits through disruption of neurodevelopment appears to extend beyond the endpoint for cortical neuronal migration, although, the persistent deficits exhibited by P1 lesion subjects suggest a secondary neurodevelopmental window at the time of cortical neuromigration representing a peak period of vulnerability.
Albert M Galaburda - One of the best experts on this subject based on the ideXlab platform.
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changes in efferent and afferent connectivity in rats with induced cerebrocortical microgyria
The Journal of Comparative Neurology, 2000Co-Authors: Glenn D Rosen, Albert M Galaburda, Deborah BursteinAbstract:Freezing injury to the cortical plate at postnatal day (P) 1 initiates a cascade of events that ultimately result in a focal neocortical malformation resembling human 4-layered microgyria. This malformation has been associated with widespread changes in neocortical and thalamic architecture and physiology. It was hypothesized that at least some of these alterations could result from connectional reorganization following early injury. The current experiment was designed to delineate the efferent and afferent connections between the cerebral hemispheres and between the cortex and thalamus of rats with induced cerebrocortical microgyria. Microgyria were induced in the parietal cortex of rats by freezing injury on postnatal day 1. In adulthood, injections of biotinylated dextran amine were made either in the microgyric cortex, in homologous regions of the opposite hemisphere, or in ipsilateral ventrobasal complex of the thalamus. Appropriately directed connections to homotopic areas were seen in some but not all microgyric rats. In addition, heterotopic projections to frontal and secondary sensorimotor cortices were noted. Projections from homotopic regions in the hemisphere opposite to the malformation terminated most often in the medial portions of the microgyrus or avoided it entirely. There were almost no thalamocortical or corticothalamic projections between the ventrobasal complex and the microgyrus itself, although a dense plexus of thalamocortical fibers was often noted at the border between the malformed and normal cortex. These connectional changes may help explain disturbances in architecture, physiology, and behavior associated with these focal malformations. J. Comp. Neurol. 418:
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cerebral microgyria thalamic cell size and auditory temporal processing in male and female rats
Cerebral Cortex, 1997Co-Authors: A E Herman, Albert M Galaburda, Roslyn Holly Fitch, A. R. Carter, Glenn D RosenAbstract:Induction of microgyria by freezing injury to the developing somatosensory cortex of neonatal rats causes a defect in fast auditory processing in males, but not in females. It was speculated that early damage to the cortex has sexually dimorphic cascading effects on other brain regions mediating auditory processing, which can lead to the observed behavioral deficits. In the current series of experiments, bilateral microgyri were induced by placement of a freezing probe on the skulls of newborn male and female rats, and these animals were tested in adulthood for auditory temporal processing. Control animals received sham surgery. The brains from these animals were embedded in celloidin, cut in the coronal plane and the following morphometric measures assessed: microgyric volume, medial geniculate nucleus (MGN) volume, cell number, and cell size, and, as a control, dorsal lateral geniculate nucleus (dLGN) volume, cell number and cell size. There were no sex differences in the cortical pathology of lesioned animals. However, microgyric males had more small and fewer large neurons in the MGN than their sham-operated counterparts, whereas there was no difference between lesioned and sham-operated females. There was no effect on dLGN cell size distribution in either sex. Microgyric males were significantly impaired in fast auditory temporal processing when compared to control males, whereas lesioned females exhibited no behavioral deficits. These results suggest that early injury to the cerebral cortex may have different effects on specific thalamic nuclei in males and females, with corresponding differences in behavioral effects.
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birthdates of neurons in induced microgyria
Brain Research, 1996Co-Authors: Glenn D Rosen, Gordon F Sherman, Albert M GalaburdaAbstract:Abstract Freezing injury to the cortical plate of the newborn rat results in the formation of a focal region of cerebrocortical microdysgenesis resembling. in many ways, human 4-layered microgyria. Previous research has shown that neurons born during embryonic day (E) 20 migrate through the initial damage and take their place in the cell-dense layer of the microgyric lesion. The current study was conducted to determine: (1) whether neurons generated earlier in development would be found in microgyric cortex: and (2) whether the freezing injury would stimulate production of neurons postnatally. Rat pups from mothers who were injected with S-phase markers on E15, E17. E19, and E21 were subjected to freezing injury of the cortex to induce microgyria on postnatal day (P) I. Other pups received a freezing lesion and then pulse or cumulative injections of S-phase markers for the next 72 h. Neurons born on E17 and E19 were found scattered throughout the cell-dense layer of the microgyric cortex. Early (E15) generated neurons were nearly absent in the microgyric cortex, and there was no evidence of postnatal induction of cortical neurogenesis. These results are considered in light of recent work demonstrating postnatal neocortical neurogenesis in response to early neocorlical injury.
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the neuroprotective effects of mk 801 on the induction of microgyria by freezing injury to the newborn rat neocortex
Neuroscience, 1995Co-Authors: Glenn D Rosen, Gordon F Sherman, Albert M Galaburda, Eric A SigelAbstract:Four-layered microgyria is associated with many developmental disorders, including mental retardation, epilepsy, and developmental dyslexia. Freezing lesions to the newborn rodent neocortex result in the formation of four-layered microgyria. Previous research had suggested this type of injury acts as an hypoxic/ischemic event to the developing cortical plate. The current study examines the effectiveness of the non-competitive N-methyl-D-aspartate receptor antagonist dizocilpine (MK-801) in protecting against freezing injury to the newborn rat cortical plate. Three groups of rats received freezing injury to the cortical plate on the first day of life (postnatal day 1). Two groups were treated with MK-801 (1 or 2 mg/kg) 0.5 h before the lesion and 6 and 14 h after, while one group received saline injections. A fourth group received MK-801 injections, but did not have a freezing lesion. The volume of neocortical abnormality was determined for all three groups in rats killed after postnatal day 7. Treatment with the higher dose of MK-801 (3 × 2 mg/kg) dramatically reduced the effects of freezing injury but also resulted in over 50% mortality in both lesioned and unlesioned groups. Animals in the lesioned group, however, had a decreased volume of abnormal cortex, and there were fewer animals with microsulci than in the untreated group. This is the first demonstration of a significant anatomical neuroprotective effect in newborns leading to a reduction of cortical malformation.
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induced microgyria and auditory temporal processing in rats a model for language impairment
Cerebral Cortex, 1994Co-Authors: Roslyn Holly Fitch, Albert M Galaburda, Christine P. Brown, Paula Tallal, Glenn D RosenAbstract:: Studies have shown the existence of minor developmental cortical malformations, including microgyria, in the brains of dyslexics. Concomitant studies have shown that language-impaired individuals exhibit severe deficits in the discrimination of rapidly presented auditory stimuli, including phonological and nonverbal stimuli (i.e., sequential tones). In an effort to relate these results, male rats with neonatally induced microgyria were tested in an operant paradigm for auditory discrimination of stimuli consisting of two sequential tones. Subjects were shaped to perform a go/no-go target identification, using water reinforcement. Stimuli were reduced in duration from 540 to 249 msec across 24 d of testing. Results showed that all subjects were able to discriminate at longer stimulus durations. However, bilaterally lesioned subjects showed specific impairment at stimulus durations of 332 msec or less, and were significantly depressed in comparison to shams. Right- and left-lesioned subjects were significantly depressed in comparison to shams at the shortest duration (249 msec). These results suggest a possible link between the neuropathologic anomalies and the auditory temporal processing deficits reported for language-impaired individuals.
Holly R Fitch - One of the best experts on this subject based on the ideXlab platform.
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effects of test experience and neocortical microgyria on spatial and non spatial learning in rats
Behavioural Brain Research, 2012Co-Authors: Steven W Threlkeld, Glenn D Rosen, Caitlin E Szalkowski, Dongnhu T Truong, C A St Hill, Holly R FitchAbstract:Neocortical neuronal migration anomalies such as microgyria and heterotopia have been associated with developmental language learning impairments in humans, and rapid auditory processing deficits in rodent models. Similar processing impairments have been suggested to play a causal role in human language impairment. Recent data from our group has shown spatial working memory deficits associated with neocortical microgyria in rats. Similar deficits have also been identified in humans with language learning impairments. To further explore the extent of learning deficits associated with cortical neuronal migration anomalies, we evaluated the effects of neocortical microgyria and test order experience using spatial (Morris water maze) and non-spatial water maze learning paradigms. Two independent groups were employed (G1 or G2) incorporating both microgyria and sham conditions. G1 received spatial testing for five days followed by non-spatial testing, while the reverse order was followed for G2. Initial analysis, including both test groups and both maze conditions, revealed a main effect of treatment, with microgyric rats performing significantly worse than shams. Overall analysis also revealed a task by order interaction, indicating that each group performed better on the second task as compared to the first, regardless of which task was presented first. Independent analyses of each task revealed a significant effect of treatment (microgyria worse than sham) only for the spatial water maze condition. Results indicate that prior maze experience (regardless of task type) leads to better subsequent performance. Results suggest that behavioral abnormalities associated with microgyria extend beyond auditory and working memory deficits seen in previous studies, to include spatial but not non-spatial learning impairments and that non-specific test experience may improve behavioral performance.
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low power photomicrograph of a wistar rat brain with bilateral microgyria arrows
2011Co-Authors: Ann M Peiffer, Holly R Fitch, Jennifer J Thomas, Alexandra Nicole Yurkovic, Glenn D RosenAbstract:Copyright information: Taken from "Brain weight differences associated with induced focal microgyria"BMC Neuroscience 2003;4():12-12.Published online 24 Jun 2003http://www.ncbi.nlm.nih.gov/pmc/articles/PMC166148.Copyright © 2003 Peiffer et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL. Note the normal-appearing cortex medial and lateral to the microgyria. Bar = 800 μm.
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early acoustic discrimination experience ameliorates auditory processing deficits in male rats with cortical developmental disruption
International Journal of Developmental Neuroscience, 2009Co-Authors: Steven W Threlkeld, Glenn D Rosen, C A St Hill, Holly R FitchAbstract:Abstract Auditory temporal processing deficits have been suggested to play a causal role in language learning impairments, and evidence of cortical developmental anomalies (microgyria (MG), ectopia) has been reported for language-impaired populations. Rodent models have linked these features, by showing deficits in auditory temporal discrimination for rats with neuronal migration anomalies (MG, ectopia). Since evidence from human studies suggests that training with both speech and non-speech acoustic stimuli may improve language performance in developmentally language-disabled populations, we were interested in whether/how maturation and early experience might influence auditory processing deficits seen in male rats with induced focal cortical MG. Results showed that for both simple (Normal single tone), as well as increasingly complex auditory discrimination tasks (silent gap in white noise and FM sweep), prior experience significantly improved acoustic discrimination performance—in fact, beyond improvements seen with maturation only. Further, we replicated evidence that young adult rats with MG were significantly impaired at discriminating FM sweeps compared to shams. However, these MG effects were no longer seen when experienced subjects were retested in adulthood (even though deficits in short duration FM sweep detection were seen for adult MG rats with no early experience). Thus while some improvements in auditory processing were seen with normal maturation, the effects of early experience were even more profound, in fact resulting in amelioration of MG effects seen at earlier ages. These findings support the clinical view that early training intervention with appropriate acoustic stimuli could similarly ameliorate long-term processing impairments seen in some language-impaired children.
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persistent spatial working memory deficits in rats with bilateral cortical microgyria
Behavioral and Brain Functions, 2008Co-Authors: Holly R Fitch, Glenn D Rosen, Heather Breslawski, James J ChrobakAbstract:Background: Anomalies of cortical neuronal migration (e.g., microgyria (MG) and/or ectopias) are associated with a variety of language and cognitive deficits in human populations. In rodents, postnatal focal freezing lesions lead to the formation of cortical microgyria similar to those seen in human dyslexic brains, and also cause subsequent deficits in rapid auditory processing similar to those reported in human language impaired populations. Thus convergent findings support the ongoing study of disruptions in neuronal migration in rats as a putative model to provide insight on human language disability. Since deficits in working memory using both verbal and non-verbal tasks also characterize dyslexic populations, the present study examined the effects of neonatally induced bilateral cortical microgyria (MG) on working memory in adult male rats. Methods: A delayed match-to-sample radial water maze task, in which the goal arm was altered among eight locations on a daily basis, was used to assess working memory performance in MG (n = 8) and sham (n = 10) littermates. Results: Over a period of 60 sessions of testing (each session comprising one pre-delay sample trial, and one post-delay test trial), all rats showed learning as evidenced by a significant decrease in overall test errors. However, MG rats made significantly more errors than shams during initial testing, and this memory deficit was still evident after 60 days (12 weeks) of testing. Analyses performed on daily error patterns showed that over the course of testing, MG rats utilized a strategy similar to shams (but with less effectiveness, as indicated by more errors). Conclusion: These results indicate persistent abnormalities in the spatial working memory system in rats with induced disruptions of neocortical neuronal migration.
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use of a modified prepulse inhibition paradigm to assess complex auditory discrimination in rodents
Brain Research Bulletin, 2008Co-Authors: Holly R Fitch, Steven W Threlkeld, Melissa M Mcclure, Ann M PeifferAbstract:Abstract Prepulse inhibition (PPI; also termed startle reduction or reflex modification, see Ref. [H.S. Hoffman, J.R. Ison, Reflex modification in the domain of startle: I. Some empirical findings and their implications for how the nervous system processes sensory input, Psychol. Rev. 87 (1980) 175–189]) provides an efficient and accurate method to assess both simple and complex acoustic discrimination in rodents [J.R. Ison, G.R. Hammond, Modification of the startle reflex in the rat by changes in the auditory and visual environments, J. Comp. Physiol. Psychol. 75 (1971) 435–452]. Assessment of acoustic processing using PPI is less time consuming than operant conditioning paradigms, allows for the testing of many subjects simultaneously, and largely eliminates confounds due to motivation and attention [M. Clark, G. Rosen, P. Tallal, R.H. Fitch, Impaired processing of complex auditory stimuli in rats with induced cerebrocortical microgyria, J. Cog. Neurosci. 12 (2000) 828–839]. Moreover, PPI procedures allow for data acquisition from the first day of testing, and can be used on rats as young as P14–15 [J.T. Friedman, A. Peiffer, M. Clark, A. Benasich, R.H. Fitch, Age and experience related improvements in gap detection in the rat, Dev. Brain Res. 152 (2004) 83–91; M. McClure, S. Threlkeld, G. Rosen, R.H. Fitch, Rapid auditory processing and learning deficits in rats with P1 versus P7 neonatal hypoxic-ischemic injury, Behav. Brain Res. 172 (2006) 114–121; S.W. Threlkeld, M.M. McClure, G.D. Rosen, R.H. Fitch, Developmental timeframes for the induction of microgyria and rapid auditory processing deficits in the rat, Brain Res. 1109 (2006) 22–31]. For these and additional reasons, the PPI paradigm has more recently been adapted to the assessment of complex acoustic discrimination (tone sequences and FM sweeps), and applied to the study of normally developing as well as neuropathologically affected rodent populations. The purpose of the current review is to provide a background on the PPI paradigm, and to summarize what has been learned more recently using modified versions of PPI with rodent models.
Chitra Sarkar - One of the best experts on this subject based on the ideXlab platform.
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endoscopic assisted through a mini craniotomy corpus callosotomy combined with anterior hippocampal and posterior commissurotomy in lennox gastaut syndrome a pilot study to establish its safety and efficacy
Neurosurgery, 2016Co-Authors: Sarat P Chandra, Nilesh Kurwale, S S Chibber, J Banerji, Rekha Dwivedi, Ajay Garg, C S Bal, Manjul Tripathi, Chitra SarkarAbstract:BACKGROUND Corpus callosotomy is a palliative procedure especially for Lennox-Gastaut semiology without localization with drop attacks. OBJECTIVE To describe endoscopic-assisted complete corpus callosotomy combined with anterior, hippocampal, and posterior commissurotomy. METHODS Patients with drug refractory epilepsy having drop attacks as the predominant seizure type, bilateral abnormalities on imaging, and moderate to severe mental retardation were included. All underwent a complete workup (including magnetic resonance imaging). RESULTS Patients (n = 16, mean age 11.4 ± 6.4 years, range 6-19 years) had a mean seizure frequency of 24.5 ± 19.8/days (range 1-60) and a mean intelligence quotient of 25.23 ± 10.71. All had syndromic diagnosis of Lennox-Gastaut syndrome, with the following etiologies: hypoxic insult (10), lissencephaly (2), bilateral band heterotropia (2), and microgyria and pachygyria (2). Surgery included complete callosotomy and the section of anterior and posterior commissure by microscopic approach through a mini craniotomy (11) and endoscopic-assisted approach (5). Complications included meningitis (1), hyperammonemic encephalopathy (2), and acute transient disconnection (5). There was no mortality or long-term morbidity. Mean follow-up was 18 ± 4.7 months (range 16-27 months). Drop attacks stopped in all. Seizure frequency/duration decreased >90% in 10 patients and >50% in 5 patients, and increased in 1 patient. All patients attained presurgical functional levels in 3 to 6 months. Child behavior checklist scores showed no deterioration. Parental questionnaires reported 90% satisfaction attributed to the control of drop attacks. The series was compared retrospectively with an age/sex-matched cohort (where a callosotomy only was performed), and showed better outcome for drop attacks (P < .003). CONCLUSION This preliminary study demonstrated the efficacy and safety of complete callosotomy with anterior, hippocampal, and posterior commissurotomy in Lennox-Gastaut syndrome (drop attacks) with moderate to severe mental retardation.
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endoscopic assisted through a mini craniotomy corpus callosotomy combined with anterior hippocampal and posterior commissurotomy in lennox gastaut syndrome a pilot study to establish its safety and efficacy
Neurosurgery, 2016Co-Authors: Sarat P Chandra, Nilesh Kurwale, S S Chibber, J Banerji, Rekha Dwivedi, Ajay Garg, Madhavi Tripathi, Chitra SarkarAbstract:BACKGROUND: Corpus callosotomy is a palliative procedure especially for Lennox-Gastaut semiology without localization with drop attacks. OBJECTIVE: To describe endoscopic-assisted complete corpus callosotomy combined with anterior, hippocampal, and posterior commissurotomy. METHODS: Patients with drug refractory epilepsy having drop attacks as the predominant seizure type, bilateral abnormalities on imaging, and moderate to severe mental retardation were included. All underwent a complete workup (including magnetic resonance imaging). RESULTS: Patients (n = 16, mean age 11.4 ± 6.4 years, range 6-19 years) had a mean seizure frequency of 24.5 ± 19.8/days (range 1-60) and a mean intelligence quotient of 25.23 ± 10.71. All had syndromic diagnosis of Lennox-Gastaut syndrome, with the following etiologies: hypoxic insult (10), lissencephaly (2), bilateral band heterotropia (2), and microgyria and pachygyria (2). Surgery included complete callosotomy and the section of anterior and posterior commissure by microscopic approach through a mini craniotomy (11) and endoscopic-assisted approach (5). Complications included meningitis (1), hyperammonemic encephalopathy (2), and acute transient disconnection (5). There was no mortality or long-term morbidity. Mean follow-up was 18 ± 4.7 months (range 16-27 months). Drop attacks stopped in all. Seizure frequency/duration decreased >90% in 10 patients and >50% in 5 patients, and increased in 1 patient. All patients attained presurgical functional levels in 3 to 6 months. Child behavior checklist scores showed no deterioration. Parental questionnaires reported 90% satisfaction attributed to the control of drop attacks. The series was compared retrospectively with an age/sex-matched cohort (where a callosotomy only was performed), and showed better outcome for drop attacks (P < .003). CONCLUSION: This preliminary study demonstrated the efficacy and safety of complete callosotomy with anterior, hippocampal, and posterior commissurotomy in Lennox-Gastaut syndrome (drop attacks) with moderate to severe mental retardation.
Sarat P Chandra - One of the best experts on this subject based on the ideXlab platform.
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endoscopic assisted through a mini craniotomy corpus callosotomy combined with anterior hippocampal and posterior commissurotomy in lennox gastaut syndrome a pilot study to establish its safety and efficacy
Neurosurgery, 2016Co-Authors: Sarat P Chandra, Nilesh Kurwale, S S Chibber, J Banerji, Rekha Dwivedi, Ajay Garg, C S Bal, Manjul Tripathi, Chitra SarkarAbstract:BACKGROUND Corpus callosotomy is a palliative procedure especially for Lennox-Gastaut semiology without localization with drop attacks. OBJECTIVE To describe endoscopic-assisted complete corpus callosotomy combined with anterior, hippocampal, and posterior commissurotomy. METHODS Patients with drug refractory epilepsy having drop attacks as the predominant seizure type, bilateral abnormalities on imaging, and moderate to severe mental retardation were included. All underwent a complete workup (including magnetic resonance imaging). RESULTS Patients (n = 16, mean age 11.4 ± 6.4 years, range 6-19 years) had a mean seizure frequency of 24.5 ± 19.8/days (range 1-60) and a mean intelligence quotient of 25.23 ± 10.71. All had syndromic diagnosis of Lennox-Gastaut syndrome, with the following etiologies: hypoxic insult (10), lissencephaly (2), bilateral band heterotropia (2), and microgyria and pachygyria (2). Surgery included complete callosotomy and the section of anterior and posterior commissure by microscopic approach through a mini craniotomy (11) and endoscopic-assisted approach (5). Complications included meningitis (1), hyperammonemic encephalopathy (2), and acute transient disconnection (5). There was no mortality or long-term morbidity. Mean follow-up was 18 ± 4.7 months (range 16-27 months). Drop attacks stopped in all. Seizure frequency/duration decreased >90% in 10 patients and >50% in 5 patients, and increased in 1 patient. All patients attained presurgical functional levels in 3 to 6 months. Child behavior checklist scores showed no deterioration. Parental questionnaires reported 90% satisfaction attributed to the control of drop attacks. The series was compared retrospectively with an age/sex-matched cohort (where a callosotomy only was performed), and showed better outcome for drop attacks (P < .003). CONCLUSION This preliminary study demonstrated the efficacy and safety of complete callosotomy with anterior, hippocampal, and posterior commissurotomy in Lennox-Gastaut syndrome (drop attacks) with moderate to severe mental retardation.
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endoscopic assisted through a mini craniotomy corpus callosotomy combined with anterior hippocampal and posterior commissurotomy in lennox gastaut syndrome a pilot study to establish its safety and efficacy
Neurosurgery, 2016Co-Authors: Sarat P Chandra, Nilesh Kurwale, S S Chibber, J Banerji, Rekha Dwivedi, Ajay Garg, Madhavi Tripathi, Chitra SarkarAbstract:BACKGROUND: Corpus callosotomy is a palliative procedure especially for Lennox-Gastaut semiology without localization with drop attacks. OBJECTIVE: To describe endoscopic-assisted complete corpus callosotomy combined with anterior, hippocampal, and posterior commissurotomy. METHODS: Patients with drug refractory epilepsy having drop attacks as the predominant seizure type, bilateral abnormalities on imaging, and moderate to severe mental retardation were included. All underwent a complete workup (including magnetic resonance imaging). RESULTS: Patients (n = 16, mean age 11.4 ± 6.4 years, range 6-19 years) had a mean seizure frequency of 24.5 ± 19.8/days (range 1-60) and a mean intelligence quotient of 25.23 ± 10.71. All had syndromic diagnosis of Lennox-Gastaut syndrome, with the following etiologies: hypoxic insult (10), lissencephaly (2), bilateral band heterotropia (2), and microgyria and pachygyria (2). Surgery included complete callosotomy and the section of anterior and posterior commissure by microscopic approach through a mini craniotomy (11) and endoscopic-assisted approach (5). Complications included meningitis (1), hyperammonemic encephalopathy (2), and acute transient disconnection (5). There was no mortality or long-term morbidity. Mean follow-up was 18 ± 4.7 months (range 16-27 months). Drop attacks stopped in all. Seizure frequency/duration decreased >90% in 10 patients and >50% in 5 patients, and increased in 1 patient. All patients attained presurgical functional levels in 3 to 6 months. Child behavior checklist scores showed no deterioration. Parental questionnaires reported 90% satisfaction attributed to the control of drop attacks. The series was compared retrospectively with an age/sex-matched cohort (where a callosotomy only was performed), and showed better outcome for drop attacks (P < .003). CONCLUSION: This preliminary study demonstrated the efficacy and safety of complete callosotomy with anterior, hippocampal, and posterior commissurotomy in Lennox-Gastaut syndrome (drop attacks) with moderate to severe mental retardation.
