Giant Brain Arteriovenous Malformation Managed by Staged Embolizations and Surgical Resection with Satisfactory Outcome

Spetzler-Martin grade V (>6 cm) arteriovenous malformations (AVMs) are traditionally considered inoperable. A 35-year-old man presented with repeated seizures for 7 years, and computed tomography arteriography and magnetic resonance imaging revealed left deep hemispheric AVM. A combination of embolization and surgical resection successfully achieved a cure of the patient. Well-equipped neurosurgery facilities can best manage selective Spetzler-Martin grade V AVMs with no neurologic deficits contrary to their traditionally inoperable concept. Successful surgery offers the patient a better quality of life.

[Central nervous system malformations: neurosurgery correlates]

Congenital malformations of the central nervous system are related to alterations in neural tube formation, including most of the neurosurgical management entities, dysraphism and craniosynostosis; alterations of neuronal proliferation; megalencefaly and microcephaly; abnormal neuronal migration, lissencephaly, pachygyria, schizencephaly, agenesis of the corpus callosum, heterotopia and cortical dysplasia, spinal malformations and spinal dysraphism. We expose the classification of different central nervous system malformations that can be corrected by surgery in the shortest possible time and involving genesis mechanisms of these injuries getting better studied from neurogenic and neuroembryological fields, this involves connecting innovative knowledge areas where alteration mechanisms in dorsal induction (neural tube) and ventral induction (telencephalization) with the current way of correction, as well as the anomalies of cell proliferation and differentiation of neuronal migration and finally the complex malformations affecting the posterior fossa and current possibilities of correcting them.

Interhemispheric and quadrigeminal cysts

BACKGROUND

Interhemispheric and quadrigeminal cysts are rare lesions, similar in their propensity to present in young babies and to be associated with other central nervous system malformations, such as corpus callosum agenesia, holoprosencephaly, encephalocele, and neuronal heterotopias. Recently endoscopy has become increasingly popular in the treatment of arachnoid cysts, but experience with cysts located in the interhemispheric fissure and in the quadrigeminal cistern is limited.

METHODS

This study reviews the specific anatomy of interhemispheric and quadrigeminal cysts and their relationship with the ventricular system and subarachnoid cisterns to select the most appropriated treatment. It also reviews the literature on endoscopic treatment of interhemispheric and quadrigeminal cysts.

RESULTS

Interhemispheric and quadrigeminal cysts are not homogeneous, they have different extensions toward surrounding regions. In most cases it is presented as an area of contiguity between the cyst and ventricular system and/or subarachnoid cisterns, making endoscopic treatment feasible. The success rate for endoscopic treatment is not different from that reported in large series of arachnoid cysts elsewhere.

CONCLUSIONS

Endoscopic treatment should be considered the first-line option in the treatment of such lesions, even if some complications, such as subdural collections due to thinness of the cerebral mantle or subcutaneous CSF collections due to multifactorial associated hydrocephalus, must be expected.

Cavernous malformation of the optic chiasm: case report

We report a 14-year-old boy with cavernous malformation of the optic chiasm. He had a 2-year history of gradually worsening visual disturbance. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a suprasellar mass, findings compatible with craniopharyngioma. The mass was biopsied and histological examination confirmed cavernous malformation. On the second day after the biopsy, he suffered chiasmal apoplexy due to intratumoural haemorrhage, lost visual acuity and developed a field cut. Cavernous malformations arising from the optic nerve and chiasm are extremely rare; only 29 cases have been reported to date. Most patients manifested acute visual acuity and visual field disturbances. Although MRI findings of cavernous malformations in the brain parenchyma have been reported, MRI findings on the optic nerve and chiasm may not be completely diagnostic. Of the 29 documented patients, 16 underwent total resection of the lesion without exacerbation of their preoperative symptoms; in some cases, resection was complicated by risk of damage to the surrounding neural tissue. As patients may suffer intratumoural haemorrhage after biopsy or partial removal of the lesion, the advisability of surgical treatment of cavernous malformations of the optic nerve and chiasm must be considered carefully.

Nonfunctioning endocrine tumor arising from intracranial ectopic pancreas associated with congenital brain malformation

CASE REPORT

We report a case of a nonfunctioning pancreatic endocrine tumor arising from intracranial ectopic pancreatic tissue.

HISTORY

An 11-year-old girl was admitted to our hospital with a brain tumor. Hydrocephalus and brain malformation were apparent at birth. We first identified a mass-like lesion in the child's brain at age 4 months. We monitored the lesion yearly by magnetic resonance imaging (MRI) until she reached age 11 years. Gadolinium-enhanced MRI showed the lesion to be a tumor, which was resected.

PATHOLOGY

Examination of surgical specimens revealed a mature pancreatic tissue. We also identified monotonous neoplastic cells with round nuclei and positive immunoreactivity for synaptophysin, chromogranin A, and neurospecific enolase. However, these cells were negative for pancreatic endocrine markers. We diagnosed nonfunctioning pancreatic endocrine tumor arising from intracranial ectopic pancreatic tissue.

CONCLUSION

Migrating pancreatic elements may have induced brain malformation during embryonic development and subsequently become malignant.

Craniocervical instability in an infant with partial sacral agenesis

Sacral agenesis is an uncommon condition characterised by total or partial absence of the sacrum. The association of this condition with craniocervical junction abnormalities is extremely rare.

CASE REPORT

We describe a 3-year-old girl who, at the age of 8 months, while being investigated for short stature, was found to have significant craniocervical instability associated with anomalies of the odontoid peg. In addition to this she had partial sacral agenesis but genetic tests showed a normal karyotype. Due to the inherent difficulty of surgical fixation and immobilisation in an infant of her age, she was managed conservatively in a soft cervical orthosis. At the age of three years, surgery for decompression and stabilisation was deemed necessary due to the onset of neurological morbidity.

CONCLUSION

The authors describe this extremely rare association and discuss the difficulties faced while deciding the optimum surgical strategy for managing such young children with craniocervical instability.

Surgical treatment of polymicrogyria with advanced radiologic and neurophysiologic techniques

INTRODUCTION

Coexistence of multiple seizure types, inclusion of the motor cortex in the epileptogenic zone, and poor delimitation of the abnormal cortex make most patients with polymicrogyria (PMG) unlikely candidates for epilepsy surgery (Guerrini R et al., Epilepsy and malformations of the cerebral cortex in Epileptic syndromes in infancy, childhood and adolescence, 2005).

CASE REPORT

We present here a child with frontal PMG and intractable epilepsy evaluated with advanced magnetic resonance imaging (MRI) and neurophysiologic techniques. Diffusion tensor imaging and fiber tractography showed severe involvement of neighboring white matter tracts besides the cortex. The evaluation also included functional MRI, chronic subdural electroencephalogram monitoring, and intra-operative motor mapping. The patient had a decrease in seizure frequency and an increase in his developmental skills after the surgery.

CONCLUSION

Advanced neuroradiologic and neurophysiologic techniques are required to provide an effective and safe resection of the epileptogenic cortex in cortical dysplasias.

Ictal perfusion patterns associated with single MRI-visible focal dysplastic lesions: implications for the noninvasive delineation of the epileptogenic zone

BACKGROUND

Invasive electroencephalogram (EEG) studies are often considered necessary to localize the epileptogenic zone in partial epilepsies associated with focal dysplastic lesions (FDL). Our aim was to evaluate the relationships between subtraction ictal SPECT coregistered with magnetic resonance imaging (MRI) (SISCOM) hyperperfusion clusters and MRI-visible FDL, and to establish a preliminary algorithm for a noninvasive presurgical evaluation protocol for MRI-visible FDLs in patients with refractory epilepsy.

METHODS

Fifteen consecutive patients with refractory partial epilepsy and a single MRI-visible FDL underwent a noninvasive presurgical evaluation including SISCOM. Each hyperperfusion cluster was visually analyzed, automatically quantitated, and its distance form the lesion as outlined on the MRI was measured. In patients who underwent surgery, the volumes of resected brain tissue containing the FDL, the SISCOM hyperperfusion cluster, and surrounding regions were assessed on postoperative MRI and correlated with surgical outcome.

RESULTS

Fourteen of the 15 patients (93%) showed SISCOM hyperperfusion overlapping with the FDL. The FDL was detected only after reevaluation of the MRI guided by the ictal SPECT in 7 of the 15 patients (47%). Four distinct hyperperfusion patterns were observed, representing different degrees of seizure propagation. Nine patients have been operated on. Five have been seizure-free since surgery and one since a reoperation. The degree of resection of the MRI-visible FDL was the major determinant of surgical outcome. Full resection of the SISCOM hyperperfusion cluster was not required to render a patient seizure-free.

CONCLUSION

Detailed analysis of SISCOM hyperperfusion patterns is a promising tool to detect subtle FDL on MRI and to establish the epileptic nature of these lesions noninvasively. Overlap between the SISCOM hyperperfusion cluster and MRI-visible FDL in a noninvasive presurgical evaluation with concordant data may suffice to proceed to epilepsy surgery aimed at removing the MRI-visible FDL and the part of the hyperperfusion cluster within and immediately surrounding the FDL.

Electrocorticographic discharge patterns in glioneuronal tumors and focal cortical dysplasia

PURPOSE

To determine whether highly epileptiform electrocorticographical discharge patterns occur in patients with glioneuronal tumors (GNTs) and focal cortical dysplasia (FCD) and whether specific histopathological features are related to such patterns.

METHODS

The series consists of operated patients with pharmacoresistant epilepsy because of FCD or GNT between 1992 and 2003. Electrocorticography was reviewed for presence of continuous spiking, bursts, recruiting discharges, or sporadic spikes. Surgical specimens were reviewed for the presence of balloon cells, (coexisting) cortical dysplasia, and relative frequencies of neurons, glia, and microglia.

RESULTS

Continuous spiking was seen in 55% versus 12% of patients with FCD and GNT, respectively (p = 0.005). Bursts and recruiting discharges were seen in a similar proportion of patients with FCD or GNT. Ninety-one percent of patients with continuous spiking showed (coexisting) cortical dysplasia in contrast to 42% of patients without this pattern (p = 0.004). The presence of balloon cells and glia or microglia content were not associated with discharge patterns.

CONCLUSION

Continuous spiking, bursts, and recruiting discharges occur in patients with FCD and GNT. Continuous spiking was seen significantly more often in patients with FCD. When continuous spiking is found with GNT, it is likely to be associated with dysplastic regions with a high neuronal density.

Hemimegalencephaly: clinical implications and surgical treatment

INTRODUCTION

Hemimegalencephaly (HME) is a quite rare malformation of the cortical development arising from an abnormal proliferation of anomalous neuronal and glial cells that generally leads to the hypertrophy of the whole affected cerebral hemisphere. The pathogenesis of such a complex malformation is still unknown even though several hypotheses are reported in literature.

BACKGROUND

HME can occur alone or associated with neurocutaneous disorders, such as neurofibromatosis, epidermal nevus syndrome, Ito's hypomelanosis, and Klippel-Trenonay-Weber syndrome. The clinical picture is usually dominated by a severe and drug-resistant epilepsy. Other common findings are represented by macrocrania, mean/severe mental retardation, unilateral motor deficit, and hemianopia. The EEG shows different abnormal patterns, mainly characterized by suppression burst and/or hemihypsarrhythmia. Although neuroimaging and histologic investigations often show typical findings (enlarged hemisphere, malformed ventricular system, alteration of the normal gyration), the differential diagnosis with other disorders of the neuronal and glial proliferation may be difficult to obtain. Hemispherectomy/hemispherotomy is the most effective treatment to control seizure, and it also seems to provide good results on the psychomotor development when performed early, as demonstrated by the literature review and by the reported personal series reported here (20 children). The surgical therapy of HME, however, is still burdened by a quite high complication rate and mortality risk.

Mediastinal extension of an intradural teratoma in a patient with split cord malformation: case report and review of literature

INTRODUCTION

It is very rare for split cord malformation to be associated with intraspinal teratoma, and it is even rarer for such tumors in the dorsal spine to extend into the mediastinum.

CASE REPORT

The authors describe a spinal teratoma with mediastinal extension in an 8-year-old boy who presented with 1-year history of backache. Neuroimaging revealed a heterogeneously enhancing intradural lesion from D2 to D7 levels with an extension into the mediastinum at the level of D4 vertebra. A split cord malformation type 2 and a cervical syrinx were also present. At surgery, a reddish-brown vascular tumor was present from D3 to D5 levels and was found to be going anteriorly into a defect in the body of D4 vertebra. Gross total excision of the intraspinal tumor was performed. Follow-up at 1 year revealed no recurrence or metastases.

DISCUSSION

To the authors' knowledge, this is the first case of an intradural teratoma extending into the mediastinum, occurring concurrently with split cord malformation and other spinal anomalies.

Anterior cranial base glioneuronal heterotopia

BACKGROUND

Cranial base glioneuronal heterotopia is a nest or linear array of glioneuronal tissue within the basal meninges. It is thought to arise from aberrant migration of embryonic neuroepithelial tissues into the subarachnoid space. It frequently mimics tumors and may extend through basal skull bones into extracranial soft tissues.

CASE REPORT

We describe a case of intracranial anterior skull base leptomeningeal glioneuronal heterotopia in a newborn female who was diagnosed in the prenatal period by ultrasound examination to have an intracranial space-occupying lesion at 35 weeks of gestation. There was no evidence of increased intracranial pressure at birth. Magnetic resonance imaging showed a large, predominantly solid, minimally enhancing tumor in the anterior cranial fossa extending into the suprasellar region as well as into the right and left middle fossae. The gross tumor was totally resected through bifrontal craniotomy.

CONCLUSIONS

Although uncommon, diagnosis of intracranial extracerebral glioneuronal heterotopia should be strongly ascertained while evaluating intracranial space-occupying lesions during the prenatal period and infancy. It needs to be distinguished histologically from teratoma and primary central nervous system tumors. Prenatal screening for early diagnosis of the lesion is vital. The location of the lesion and its relationship to the surrounding structures should lead to an accurate diagnosis in the majority of cases. Complete resection is curative and should be the goal. Long-term prognosis is excellent in view of the benign nature and extraaxial origin of the lesion.

Intradural dermoid tumor of the posterior fossa in a child with diastematobulbia

Dermoid tumors (DTs) are rare lesions and represent 0.3% of all intracranial tumors. More than 50% of these tumors are diagnosed in childhood or early adolescence. Authors report an intradural DT of the posterior fossa in a child aged 4 years, possibly originating in the brainstem in which the diastematobulbia was detected postoperatively. Magnetic resonance imaging investigations are mandatory to diagnose these cases. The only curative treatment in DT is the total removal of the lesion. The reported case presents good recovery in the follow-up period of 3 years. The surgical intervention is particularly related to the DT type. Diastematobulbia associated with DT and the origin of the DT in the brainstem is discussed based on the literature.

Catastrophic focal epilepsy

Focal epilepsy can present with a rapidly progressing course of intractable epilepsy in children. We present a typical example of such a patient with focal seizures due to a frontal lobe cortical lesion of developmental origin. MRI and SPECT revealed abnormalities in the right frontal lobe. Surgical resection resulted in excellent outcome.

EEG and MEG source analysis of single and averaged interictal spikes reveals intrinsic epileptogenicity in focal cortical dysplasia

PURPOSE

Simultaneous interictal EEG and magnetoencephalography (MEG) recordings were used for noninvasive analysis of epileptogenicity in focal cortical dysplasia (FCD). The results of two different approach methods (multiple source analysis of averaged spikes and single dipole peak localization of single spikes) were compared with pre- and postoperative anatomic magnetic resonance imaging (MRI).

PATIENTS

We studied nine children and adolescents (age, 3.5-15.9 years) with localization-related epilepsy and FCD diagnosis based on MRI. Five patients underwent epilepsy surgery, two of them after long-term recording with subdural grid electrodes, and one after intraoperative electrocorticography.

METHODS

The 122-channel whole-head MEGs and 33-channel EEGs were recorded simultaneously for 25 to 40 min. Interictal spikes were identified visually and used as templates to search for similar spatiotemporal spike patterns throughout the recording. With the BESA program, similar spikes (r > 0.85) were detected, averaged, high-pass filtered (5 Hz) to enhance spike onset, and subjected to multiple spatiotemporal source analysis with a multishell spherical head model. Peak activity from single spikes was modeled by single dipoles for the same subset of spikes. Source localization was visualized by superposition on T1-weighted MRI and compared with the lesion identified in T1- and T2-weighted MRI. In the five cases undergoing epilepsy surgery, the results were correlated with invasive recordings, postoperative MRI, and outcome.

RESULTS

In all cases, the analysis of averaged spikes showed a localization of onset- and peak-related sources within the visible lesion for both EEG and MEG. Of the single spikes, 128 (45%; total 284) were localizable at the peak in MEG, and 170 (60%) in EEG. Of these, 91% localized within the lesion with MEG, and 93.5% with EEG. In three of five patients operated on, the resected area included the onset zones of averaged EEG and MEG spike activity. These patients had excellent postoperative outcome, whereas the others did not become seizure free.

CONCLUSIONS

Consistent MEG and EEG spike localization in the lesional zone confirmed the hypothesis of intrinsic epileptogenicity in FCD.

Surgical Treatment of Temporoparietooccipital Cortical Dysplasia in Infants: Report of Two Cases

PURPOSE

Extensive multilobar cortical dysplasia in infants commonly is first seen with catastrophic epilepsy and poses a therapeutic challenge with respect to control of epilepsy, brain development, and psychosocial outcome. Experience with surgical treatment of these lesions is limited, often not very encouraging, and holds a higher operative risk when compared with that in older children and adults.

METHODS

Two infants were evaluated for surgical control of catastrophic epilepsy present since birth, along with a significant psychomotor developmental delay. Magnetic resonance imaging showed multilobar cortical dysplasia (temporoparietooccipital) with a good electroclinical correlation. They were treated with a temporal lobectomy and posterior (parietooccipital) disconnection.

RESULTS

Both infants had excellent postoperative recovery and at follow-up (1.5 and 3.5 years) evaluation had total control of seizures with a definite "catch up" in their development, both motor and cognitive. No long-term complications have been detected to date.

CONCLUSIONS

The incorporation of disconnective techniques in the surgery for extensive multilobar cortical dysplasia in infants has made it possible to achieve excellent seizure results by maximizing the extent of surgical treatment to include the entire epileptogenic zone. These techniques decrease perioperative morbidity, and we believe would decrease the potential for the development of long-term complications associated with large brain excisions.

Prevention by maternal pancreatic islet transplantation of hypothalamic malformation in offspring of diabetic mother rats is already detectable at weaning

Exposure to gestational diabetes (GD) in rats leads to dysplasia of the ventromedial hypothalamic nucleus (VMN), decisively involved into the regulation of body weight and metabolism. Recently, we have shown here that VMN malformation is absent in adult offspring of GD mothers treated by pancreatic islet transplantation during gestation. We therefore now investigated whether VMN malformation and its prevention are already present at the early postnatal end of the critical hypothalamic differentiation period. Already at weaning, the total number of VMN neurons, the volume of the VMN relative to total brain volume, and the numerical density of neurons in the anterior subnucleus of the VMN were reduced in offspring of sham-transplanted mothers (all P<0.05), but did not differ between offspring of islet-transplanted mothers and controls. No morphometric alterations occurred in the paraventricular hypothalamic nucleus. In conclusion, prevention of VMN malformation in offspring of islet-transplanted diabetic mothers is a direct consequence of normalized maternal metabolism during critical perinatal development.

Aberrant Corneal Nerve Regeneration after PRK

PURPOSE

To report a case of aberrant corneal nerve regeneration after myopic photorefractive keratectomy (PRK).

METHODS

One patient underwent bilateral PRK to correct a refractive error of -5.50 D in each eye. Thirteen months after the original PRK, the left eye underwent an uncomplicated PRK reoperation to correct a regression of -1.00 D. The central corneas were examined by confocal microscopy preoperatively in both eyes, at 1 and 2 years after the original PRK in the right eye, and before and 1 and 2 years after the PRK reoperation in the left eye.

RESULTS

Aberrant anterior stromal nerves with a coiled course and irregular branching pattern were identified 22 micro m deep to the most anterior keratocyte layer at 1 year after the PRK reoperation in the left eye and remained unchanged 2 years after reoperation. No abnormal stromal nerves were identified in the left eye before the reoperation or at any time in the right eye.

CONCLUSION

Aberrant regeneration of corneal stromal nerves may occur after myopic PRK reoperation.

Surgical-site infection following spinal fusion: a case-control study in a children's hospital

OBJECTIVES

To determine the rates of surgical-site infections (SSIs) after spinal surgery and to identify the risk factors associated with infection.

DESIGN

SSIs had been identified by active prospective surveillance. A case-control study to identify risk factors was performed retrospectively.

SETTING

University-associated, tertiary-care pediatric hospital.

PATIENTS

All patients who underwent spinal surgery between 1994 and 1998. Cases were all patients who developed an SSI after spinal surgery. Controls were patients who did not develop an SSI, matched with the cases for the presence or absence of myelodysplasia and for the surgery date closest to that of the case.

RESULTS

There were 10 infections following 125 posterior spinal fusions, 4 infections after 50 combined anterior-posterior fusions, and none after 95 other operations. The infection rate was higher in patients with myelodysplasia (32 per 100 operations) than in other patients (3.4 per 100 operations; relative risk = 9.45; P < .001). Gram-negative organisms were more common in early infections and Staphylococcus aureus in later infections. Most infections occurred in fusion involving sacral vertebrae (odds ratio [OR] = 12.0; P = .019). Antibiotic prophylaxis was more frequently suboptimal in cases than in controls (OR = 5.5; P = .034). Five patients required removal of instrumentation and 4 others required surgical debridement.

CONCLUSIONS

Patients with myelodysplasia are at a higher risk for SSIs after spinal fusion. Optimal antibiotic prophylaxis may reduce the risk of infection, especially in high-risk patients such as those with myelodysplasia or those undergoing fusion involving the sacral area.

Cajal-Retzius cells, inhibitory interneuronal populations and neuropeptide Y expression in focal cortical dysplasia and microdysgenesis

Focal cortical dysplasia (FCD) and microdysgenesis (MD) are likely to represent abnormalities of radial neuronal migration during cortical development. We investigated the distribution of reelin-positive Cajal-Retzius cells, known to be important in the later stages of radial neuronal migration and cortical organization, in 12 surgical cases of both MD and FCD. Quantitation revealed significantly higher numbers of these cells in MD cases compared to controls. As the majority of cortical interneurones arise via tangential rather than radial migration, we studied the distribution and morphology of inhibitory interneuronal subsets immunolabelled for calbindin, parvalbumin and calretinin within these malformations. Frequent findings were a reduction of inhibitory interneurones in the region of FCD and abnormally localised hypertrophic or multipolar calbindin-positive interneurones in both FCD and MD. Neuropeptide Y immunostaining showed a striking increase in the density of the superficial plexus of fibres in both MD and FCD cases in addition to labelling of dysplastic neurones, which may represent an adaptive anti-convulsant mechanism to dampen down seizure propagation.

Focal cortical dysplasias: MR imaging, histopathologic, and clinical correlations in surgically treated patients with epilepsy

BACKGROUND AND PURPOSE

Focal cortical dysplasia (FCD) covers a spectrum of conditions in which the neuropathologic and electroclinic presentations and the surgical outcomes vary. The aim of this study was to identify the MR features of histologic subtypes of FCD that would be useful for differential diagnosis.

METHODS

We reviewed the MR data of 49 patients treated surgically for intractable partial epilepsy, who received a histologic diagnosis of FCD not associated with other brain abnormalities except hippocampal sclerosis and who were classified by histologic criteria as having architectural dysplasia (28 patients), cytoarchitectural dysplasia (six patients), or Taylor's FCD (15 patients).

RESULTS

From the MR features, it was generally possible to distinguish Taylor's FCD from architectural or cytoarchitectural dysplasias (non-Taylor's FCD). Findings suggesting Taylor's FCD were focal cortical thickening, blurring of the gray-white matter junction, and hyperintensity (on T2-weighted images) of subcortical white matter often tapering toward the ventricle. Focal brain hypoplasia with shrinkage and moderate signal intensity alterations in the white matter core were present in most patients with architectural dysplasia. The lesion was generally extratemporal in Taylor's FCD and temporal in architectural dysplasia. Ipsilateral hippocampal sclerosis was often present in architectural dysplasia (dual abnormality).

CONCLUSIONS

In patients with FCD, Taylor's FCD and non-Taylor's FCD can usually be distinguished with MR imaging, although some overlap exists. A provisional MR diagnosis is important for presurgical investigations and surgical planning and may have prognostic implications.

Successful neurosurgical treatment of childhood complex partial status epilepticus with focal resection

The treatment of complex partial status epilepticus continues to be controversial, especially with regard to the intensity of the treatment. Medical therapy and drug-induced coma are sometimes required. Rarely this may not be effective. A healthy 4-year old girl was first seen in complex partial status epilepticus. She had a 1-year history of cryptogenic partial-onset seizures. Detailed magnetic resonance imaging (MRI) studies were normal. Her course was refractory to multiple medical therapies and multiple subpial transection (MST). An urgent epilepsy surgery evaluation resulted in a focal cortical resection being performed over the right mesial parietal region with resultant seizure freedom and no significant neurologic deficit 2 years later. This patient illustrates the need to consider occult focal cortical dysplasia as a cause of nonconvulsive status epilepticus (NCSE) in children, and if it is not responsive to medical management, the utility of performing an urgent epilepsy surgery evaluation.

[Advances in the treatment of newborns with congenital malformations]

Authors analyzed the type and the number of treated congenital malformations in 544 newborns operated between 1992-2001 in the Department of Paediatric Surgery in the Institute of Mother and Child. The patients were divided in the following groups: digestive tract defects, abdominal wall and diaphragm defects, neural tube defects, urinary track defects, craniofacial and brain defects and others anomalies occurring rarely. Most of the operations were preformed in the first 48 hours of life. Since 1995 special newborn transport, early cardiac surgery and neonatal intensive care have been introduced. Total mortality of operated newborns and death in particular groups were analyzed. The implemented elements caused a decrease in mortality from 36 to 13 percent. In the authors' opinion improvement in treatment results is due to earlier diagnosis and better understanding of pathophysiology of the defects, introduction of noninvasive pre- and postnatal diagnostics and establishment of centres specialized in neonatal surgery and intensive care.

Surgical resection for intractable epilepsy in "double cortex" syndrome yields inadequate results

PURPOSE

To analyze the results of surgical treatment of intractable epilepsy in patients with subcortical band heterotopia, or double cortex syndrome, a diffuse neuronal migration disorder.

METHODS

We studied eight patients (five women) with double cortex syndrome and intractable epilepsy. All had a comprehensive presurgical evaluation including prolonged video-EEG recordings and magnetic resonance imaging (MRI).

RESULTS

All patients had partial seizures, with secondary generalization in six of them. Neurologic examination was normal in all. Three were of normal intelligence, and five were mildly retarded. Six patients underwent invasive EEG recordings, three of them with subdural grids and three with stereotactic implanted depth electrodes (SEEG). Although EEG recordings showed multilobar epileptic abnormalities in most patients, regional or focal seizure onset was recorded in all. MRI showed bilateral subcortical band heterotopia, asymmetric in thickness in three. An additional area of cortical thickening in the left frontal lobe was found in one patient. Surgical procedures included multiple subpial transections in two patients, frontal lesionectomy in one, temporal lobectomy with amygdalohippocampectomy in five, and an additional anterior callosotomy in one. Five patients had no significant improvement, two had some improvement, and one was greatly improved.

CONCLUSION

Our results do not support focal surgical removal of epileptogenic tissue in patients with double cortex syndrome, even in the presence of a relatively localized epileptogenic area.

Effect of multiple subpial transection on motor cortical excitability in cortical dysgenesis

We report here a 12-year-old patient with unilateral cortical dysgenesis and intractable simple partial seizure in his left arm, who underwent multiple subpial transection (MST) in the right cerebral cortex including the primary motor cortex. We investigated motor cortical excitability using multimodal transcranial magnetic stimulation (TMS) before and 1 month after MST, in which surgical cortical incisions were made with strokes 5 mm apart and 4 mm deep. Preoperative TMS studies showed hyperexcitability in the affected motor cortex as abnormally prolonged muscle responses to TMS with a wide cortical motor map, which were markedly reduced following the operation. The preoperative motor evoked potentials were large and polyphasic, and consisted of early and late components. The late component was completely abolished after MST, suggesting that this component might be due to activation of the corticospinal tract neurones by long recurrent axon branches of dysplastic excitatory pyramidal neurones, which were cut by MST, or by delayed, polysynaptic intracortical conduction with marked temporal dispersion. Intracortical inhibition in the affected motor cortex was also disrupted preoperatively and improved after MST. Postoperative recruitment order of muscle responses to TMS was bilaterally symmetrical, indicating that MST did not interfere with the function of the corticospinal tract neurones. The patient showed fair motor recovery and good seizure control after the operation. These results of TMS studies demonstrated the remarkable effectiveness of MST not only on intractable seizure but also on abnormal motor cortical organization and hyperexcitability in cortical dysgenesis.

Congenital malformations of the brain--a neurosurgical perspective at the close of the twentieth century

Current classifications, indications for surgery, operative options and outcome statistics available to neurosurgeons for the management of congenital encephaloceles, arachnoid cysts and the Dandy-Walker complex are reviewed.