Contralateral MRI abnormalities affect seizure and cognitive outcome after hemispherectomy

OBJECTIVE

To explore whether EEG and MRI abnormalities in the "healthy" hemisphere influence seizure and cognitive outcome after functional hemispherectomy.

METHODS

This is a retrospective consecutive cohort study of 43 children who underwent functional hemispherectomy between 1994 and 2008. Results of preoperative EEG recordings were reviewed for the existence of (inter)ictal epileptic or background abnormalities in the contralateral hemisphere. Preoperative MRIs were reexamined for the existence of unequivocal contralateral abnormalities. Postoperative seizure status was assessed, and of 34 children, IQ or mental developmental index (MDI) scores were obtained preoperatively and postoperatively. Seizure freedom was defined as Engel 1A. Contralateral EEG and MRI abnormalities were studied in relation to seizure and cognitive outcome.

RESULTS

Thirty-three children achieved seizure freedom (77%). Of the 11 patients with contralateral MRI abnormalities, only 45% were seizure free, compared with 88% of the 32 patients without contralateral MRI lesions (p = 0.030). Children with contralateral MRI abnormalities more often were severely retarded after surgery (MDI/IQ <55; 90% vs 42%, p = 0.030). Postoperative MDI/IQ scores improved in none of the children with, but in 38% of those without contralateral MRI abnormalities (p = 0.034). Contralateral epileptic or background EEG abnormalities did not affect seizure outcome or postoperative cognitive performance. Four of 6 children with bilateral epileptic encephalopathy reached seizure freedom.

CONCLUSION

Unambiguous contralateral MRI abnormalities are significantly associated with seizure recurrence, severe mental delay, and lack of cognitive improvement and may be considered a relative contraindication for hemispherectomy. Contralateral EEG abnormalities do not negatively influence postsurgical outcome.

Lateralization of motor innervation in children with intractable focal epilepsy--a TMS and fMRI study

PURPOSE

To correlate hand function with lateralization of motor innervation, as studied with transcranial magnetic stimulation (TMS) and functional magnetic imaging (fMRI), in children with intractable epilepsy and lesions in the vicinity of the motor cortex.

METHODS

In 34 children hand motor function was examined and motor evoked potentials (MEPs) were recorded after TMS of both hemispheres, establishing lateralization of corticospinal innervation. When feasible, patients underwent fMRI using a manual motor task.

RESULTS

Good function of the contralesional hand was associated with early lesions (p=0.02). Lateralization of motor innervation to the contralesional hand correlated with quality of motor function (p=0.001); 83% of children with poor hand function had ipsi- or bilateral innervation, whereas all children with good hand function had pure contralateral control. Mirror movements during movement of the unaffected hand predicted ipsilateral contribution to motor innervation (p=0.006). Fourteen children who had no TMS responses were younger than those with elicitable MEPs (p<0.001). TMS led to a temporary increase of seizure frequency in four children. fMRI results were concordant with TMS.

CONCLUSIONS

Poor function of the contralesional hand is strongly associated with ipsilateral motor innervation. Reorganization in the lesioned hemisphere mainly occurs in early developmental lesions and seems efficient in maintaining good hand function. Clinical examination of hand function has predictive value for the pattern of motor innervation prior to epilepsy surgery, which in older children can further be established by TMS and fMRI.

Clinical presentation, associated disorders and aetiological moments in Cerebral Palsy: A Dutch population-based study

PURPOSE

Cerebral Palsy (CP) contains varying clinical presentations, associated disorders and aetiological moments. Quantitative data and trends on these aspects were lacking in The Netherlands.

METHOD

Within a population-based study on prevalence, presentation and functioning of Dutch children with CP born in the years 1977-1988, individual history taking, examination and medical file checking was done by experienced clinicians. Clinical subtypes, motor disability, important co-morbidity (mental retardation, visual disability and epilepsy) were recorded, aetiological moments identified if possible. By comparing the four most recent years with the earlier years possible trends were studied.

RESULTS

A quarter of children beforehand recorded as CP did not meet inclusion criteria after individual examination. Spastic subtypes accounted for over 90% of all CP cases: bilateral spastic cerebral palsy as a group are the majority although spastic hemiplegia is percentage-wise the largest individual clinical subtype. Epilepsy and mental retardation are common. Clinical patterns and associated disorders remained rather constant comparing earlier to more recent birth years.

CONCLUSIONS

An early diagnosis of CP may be challenged. General clinical patterns remained rather constant in following years, as did most studied items. Even if this study revealed a prevalence rise, no aspect stood out as a possible explanation for this prevalence rise. Comparable studies performed elsewhere showed similar findings.

Characterization of febrile seizures and febrile seizure susceptibility in mouse inbred strains

Febrile seizures (FS) are the most prevalent seizures in children. Although FS are largely benign, complex FS increase the risk to develop temporal lobe epilepsy (TLE). Studies in rat models for FS have provided information about functional changes in the hippocampus after complex FS. However, our knowledge about the genes and pathways involved in the causes and consequences of FS is still limited. To enable molecular, genetic and knockout studies, we developed and characterized an FS model in mice and used it as a phenotypic screen to analyze FS susceptibility. Hyperthermia was induced by warm air in 10- to 14-day-old mice and induced FS in all animals. Under the conditions used, seizure-induced behavior in mice and rats was similar. In adulthood, treated mice showed increased hippocampal Ih current and seizure susceptibility, characteristics also seen after FS in rats. Of the seven genetically diverse mouse strains screened for FS susceptibility, C57BL/6J mice were among the most susceptible, whereas A/J mice were among the most resistant. Strains genetically similar to C57BL/6J also showed a susceptible phenotype. Our phenotypic data suggest that complex genetics underlie FS susceptibility and show that the C57BL/6J strain is highly susceptible to FS. As this strain has been described as resistant to convulsants, our data indicate that susceptibility genes for FS and convulsants are distinct. Insight into the mechanisms underlying seizure susceptibility and FS may help to identify markers for the early diagnosis of children at risk for complex FS and TLE and may provide new leads for treatment.

Inflammatory processes in cortical tubers and subependymal giant cell tumors of tuberous sclerosis complex

Cortical tubers and subependymal giant cell tumors (SGCT) are two major cerebral lesions associated with tuberous sclerosis complex (TSC). In the present study, we investigated immunocytochemically the inflammatory cell components and the induction of two major pro-inflammatory pathways (the interleukin (IL)-1beta and complement pathways) in tubers and SGCT resected from TSC patients. All lesions were characterized by the prominent presence of microglial cells expressing class II-antigens (HLA-DR) and, to a lesser extent, the presence of CD68-positive macrophages. We also observed perivascular and parenchymal T lymphocytes (CD3(+)) with a predominance of CD8(+) T-cytotoxic/suppressor lymphoid cells. Activated microglia and reactive astrocytes expressed IL-1beta and its signaling receptor IL-1RI, as well as components of the complement cascade, such as C1q, C3c and C3d. Albumin extravasation, with uptake in astrocytes, was observed in both tubers and SGCT, suggesting that alterations in blood brain barrier permeability are associated with inflammation in TSC-associated lesions. Our findings demonstrate a persistent and complex activation of inflammatory pathways in cortical tubers and SGCT.

Overlapping neurologic and cognitive phenotypes in patients with TSC1 or TSC2 mutations

OBJECTIVE

The purpose of this study was to systematically analyze the associations between different TSC1 and TSC2 mutations and the neurologic and cognitive phenotype in patients with tuberous sclerosis complex (TSC).

METHODS

Mutation analysis was performed in 58 patients with TSC. Epilepsy variables, including EEG, were classified. A cognition index was determined based on a comprehensive neuropsychological assessment. On three-dimensional fluid-attenuated inversion recovery MR images, an automated tuber segmentation program detected and calculated the number of tubers and the proportion of total brain volume occupied by tubers (tuber/brain proportion [TBP]).

RESULTS

As a group, patients with a TSC2 mutation had earlier age at seizure onset, lower cognition index, more tubers, and a greater TBP than those with a TSC1 mutation, but the ranges overlapped considerably. Familial cases were older at seizure onset and had a higher cognition index than nonfamilial cases. Patients with a mutation deleting or directly inactivating the tuberin GTPase activating protein (GAP) domain had more tubers and a greater TBP than those with an intact GAP domain. Patients with a truncating TSC1 or TSC2 mutation differed from those with nontruncating mutations in seizure types only.

CONCLUSIONS

Although patients with a TSC1 mutation are more likely to have a less severe neurologic and cognitive phenotype than those with a TSC2 mutation, the considerable overlap between both aspects of the phenotype implies that prediction of the neurologic and cognitive phenotypes in individuals with tuberous sclerosis complex should not be based on their particular TSC1 or TSC2 mutation.

Cognitive impairment in tuberous sclerosis complex is a multifactorial condition

OBJECTIVE

In patients with tuberous sclerosis complex (TSC), associations between tuber number, infantile spasms, and cognitive impairment have been proposed. We hypothesized that the tuber/brain proportion (TBP), the proportion of the total brain volume occupied by tubers, would be a better determinant of seizures and cognitive function than the number of tubers. We investigated tuber load, seizures, and cognitive function and their relationships.

METHODS

Tuber number and TBP were characterized on three-dimensional fluid-attenuated inversion recovery MRI with an automated tuber segmentation program. Seizure histories and EEG recordings were obtained. Intelligence equivalents were determined and an individual cognition index (a marker of cognition that incorporated multiple cognitive domains) was calculated.

RESULTS

In our sample of 61 patients with TSC, TBP was inversely related to the age at seizure onset and to the intelligence equivalent and tended to be inversely related to the cognition index. Further, a younger age at seizure onset or a history of infantile spasms was related to lower intelligence and lower cognition index. In a multivariable analysis, only age at seizure onset and cognition index were related.

CONCLUSIONS

Our systematic analysis confirms proposed relationships between tuber load, epilepsy and cognitive function in tuberous sclerosis complex (TSC), but also indicates that tuber/brain proportion is a better predictor of cognitive function than tuber number and that age at seizure onset is the only independent determinant of cognitive function. Seizure control should be the principal neurointervention in patients with TSC.

Familial occurrence of brain arteriovenous malformations: a systematic review

BACKGROUND

Brain arteriovenous malformations (BAVMs) are thought to be sporadic developmental vascular lesions, but familial occurrence has been described. We compared the characteristics of patients with familial BAVMs with those of patients with sporadic BAVMs.

METHODS

We systematically reviewed the literature on patients with familial BAVMs. Three families that were found in our centre were added. Age, sex distribution and clinical presentation of the identified patients were compared with those in population based series of patients with sporadic BAVMs. Furthermore, we calculated the difference in mean age at diagnosis of parents and children to study possible anticipation.

RESULTS

We identified 53 patients in 25 families with BAVMs. Mean age at diagnosis of patients with familial BAVMs was 27 years (range 9 months to 58 years), which was younger than in the reference population (difference between means 8 years, 95% CI 3 to 13 years). Patients with familial BAVMs did not differ from the reference populations with respect to sex or mode of presentation. In families with BAVMs in successive generations, the age of the child at diagnosis was younger than the age of the parent (difference between means 22 years, 95% CI 13 to 30 years), which suggests clinical anticipation.

CONCLUSIONS

Few patients with familial BAVMs have been described. These patients were diagnosed at a younger age than sporadic BAVMs whereas their mode of presentation was similar. Although there are indications of anticipation, it remains as yet unclear whether the described families represent accidental aggregation or indicate true familial occurrence of BAVMs.

[Intracranial EEG monitoring for epilepsy surgery using electrode grids--results in the first 22 Dutch patients]

OBJECTIVE

Description of initial experiences with subdural electrode grids in patients with refractory focal epilepsy as additional diagnostic tool for epilepsy surgery. Using these electrodes, the attacks were recorded during a number of days and the cerebral cortex was electrically stimulated in order to map the functional areas.

DESIGN

Retrospective.

METHOD

Data were collected from patients in whom subdural electrode grids had been placed between 1 September 1999 and 31 August 2004. All patients underwent a neurological examination and a neuropsychological test before the implantation. At the follow-up examination, the results with regard to function and the frequency of attacks were noted, as well as the complications.

RESULTS

Electrodes were placed in 22 patients: 9 women and 13 men with an average age of 27 years (range: 5-42). The implantation lasted for an average of 7 days (range: 3-10). In 4 patients, increased seizures during implantation required intravenous anticonvulsant treatment. Severe but transitory complications were seen in 4 patients (meningitis, subdural haematoma and ischaemia). 19 patients underwent a therapeutic resection. A postoperative decline in language skills was noted in 1 patient, while another 2 scored poorer in verbal tests. A permanent decline in sensorimotor function was seen in 1 patient, but this had been foreseen. Of the 16 operated patients with a duration of follow-up of at least 1 year, so were (practically) free of attacks, and another 3 patients had significantly fewer attacks.

CONCLUSION

Registration with intracranial electrodes makes it possible to treat epileptic patients surgically by excision of brain tissue near critical areas. Such intensive monitoring is, however, not without risk and this must be weighed against the potential benefits.

Propofol and thiopental for refractory status epilepticus in children

To assess safety and efficacy of propofol and thiopental for refractory status epilepticus (RSE) in children, the authors reviewed 34 episodes of RSE. Thiopental was effective in most patients, but there were serious side effects. Propofol was used according to a strict protocol. It was effective in most patients, so that thiopental was not needed. Side effects were infrequent, of minor severity, and fully reversible. The authors suggest the use of propofol before thiopental.

Thrombin-stimulated glutamate uptake in human platelets is predominantly mediated by the glial glutamate transporter EAAT2

Glutamate toxicity has been implicated in the pathogenesis of various neurological diseases. Glial glutamate transporters play a key role in the regulation of extracellular glutamate levels in the brain by removing glutamate from the extracellular fluid. Since human blood platelets possess an active glutamate uptake system, they have been used as a peripheral model of glutamate transport in the central nervous system (CNS). The present study is aimed at identifying the glutamate transporter on blood platelets, and to asses the influence of platelet activation on glutamate uptake. Platelets from healthy donors showed Na+-dependent glutamate uptake (Km, 3.5+/-0.9 microM; Vmax, 2.8+/-0.2 pmol glutamate/75 x 10(6)platelets/30 min), which could be blocked dose-dependently by the EAAT specific inhibitors DL-threo-E-benzyloxyaspartate (TBOA), L-trans-pyrrolidine-2,4-dicarboxylic acid (tPDC) and high concentrations of the EAAT2 inhibitor dihydrokainate (DHK). Analysis of platelet homogenates on Western blots showed EAAT2 as the predominant glutamate transporter. Platelet activation by thrombin caused an increase in glutamate uptake, which could be inhibited by TBOA and the EAAT2 inhibitor DHK. Kinetic analysis showed recruitment of new transporters to the membrane. Indeed, Western blot analysis of subcellular fractions revealed that alpha-granules, which fuse with the membrane upon thrombin stimulation, contained significant EAAT2 immunoreactivity. Inhibition of the second messengers involved in alpha-granule secretion (protein kinase C, phosphatidylinositol-3-kinase) inhibited thrombin-stimulated uptake, but not basal uptake. These data show that the glial EAAT2 is the predominant glutamate transporter on blood platelets and suggest, that thrombin increases glutamate uptake capacity by recruiting new transporters (EAAT2) from alpha-granules.

Role of visual dysfunction in postural control in children with cerebral palsy

Introduction: Deficient postural control is one of the key problems in cerebral palsy (CP). Little, however, is known about the specific nature of postural problems of children with CP, nor of the relation between abnormal posture and dysfunction of the visual system. Aim of the study: To provide additional information on the association of abnormalities in postural control and visual dysfunction of the anterior or posterior part of the visual system. Methods: Data resulting from ophthalmologic, orthoptic, neurological, neuro-radiological, and ethological investigations of more than 313 neurologically impaired children were retrospectively analyzed. Results: Abnormal postural control related to ocular and ocular motor disorders consisted of anomalous head control and subsequent abnormal head posture and torticollis. The abnormal postural control related to retrochiasmatical damage of the visual system consisted of a torticollis combined with adjustment of the upper part of the body, as if at the same time adapting to a combination of defects and optimizing residual visual functions. Conclusion: Visual dysfunctions play a distinct role in the postural control of children with CP.

Epilepsy surgery does not harm motor performance of children and adolescents

The impact of epilepsy surgery on motor performance, activities of daily life (ADL) and caregiver assistance was assessed in 37 children (age range 0.1-15.4 years) with pharmacologically untreatable epilepsy, 17 of whom were also diagnosed as having spasticity of cerebral origin. All patients underwent epilepsy surgery between 1996 and 2001 at the Wilhelmina University Children's Hospital and were assessed using a standard protocol at fixed intervals: before surgery and 6 months, 1 year and 2 years after surgery. The type of surgery was hemispherectomy (n = 14) and temporal (n = 14), frontal (n = 4), parietal (n = 2) and central (n = 2) resection. One child underwent callosotomy. Engel's classification was used to determine seizure outcome. Impairments were measured in terms of muscle strength, range of motion and muscle tone. Motor performance of infants and children without spasticity was measured using the Movement Assessment Battery for Children (M-ABC). The Gross Motor Function Measure (GMFM-88) was used in children with spasticity, the severity of motor disability in this group being determined by means of the Gross Motor Function Classification System (GMFCS). Daily activities and caregiver's assistance were measured in all children using the Pediatric Evaluation of Disability Inventory (PEDI). Twenty-four months after surgery 74% of the children could be classified as Engel class 1, indicating a significant seizure reduction. Impairments revealed some decrease in muscle strength and range of motion in the group with spasticity. Scores improved statistically significantly at group level on M-ABC and GMFM (P < 0.05). Improvement in activities of daily life and caregiver's assistance could not be measured in children without spasticity because of the ceiling effect of the PEDI, but children with spasticity improved significantly with respect to these parameters (PEDI) (P < 0.05). Hence, epilepsy surgery does not harm motor performance in children with or without spasticity.

Differential localization of hamartin and tuberin and increased S6 phosphorylation in a tuber

In a tuberous sclerosis patient with a mutation in the TSC1 tumor suppressor gene, no second-hit mutation was found in a resected cortical tuber. Tuber giant cells showed predominantly nuclear hamartin, cytosolic tuberin, and hyperphosphorylation of S6. Differential accumulation of hamartin and tuberin in separate cellular compartments of giant cells may prevent formation of the hamartin-tuberin complex, resulting in increased S6 phosphorylation. These data provide an alternative mechanism for tuberogenesis.

Functional consequences of hemispherectomy

Using the International Classification of Functioning Disability and Health (ICF) (WHO, 2001), impairments, activities and social participation are reported in 12 children (mean age at surgery 5.9 years) who were investigated before and three times over a 2-year period after hemispherectomy. Impairments were assessed (i) in terms of seizure frequency (Engel classification) and seizure severity (HASS) and (ii) with respect to muscle strength (MRC), range of motion (JAM score) and muscle tone (modified Ashworth scale). Activities were assessed in terms of gross motor functioning (GMFM) and self-care, mobility and social function (PEDI). Participation was assessed in terms of epilepsy-related restrictions and quantified by means of the Hague Restrictions in Childhood Epilepsy Scale (HARCES). Nine out of 12 children could be classified as free of seizures (Engel class I), and in the remaining three seizure frequency was Engel class III. HASS scores showed maximum improvement in 10 out of 12 children and near-maximum improvement in the two remaining children. Muscle strength and muscle tone on the side of the body contralateral to the hemispherectomy, which were already decreased preoperatively, decreased even further in the first 6 months after surgery, but returned to the presurgical baseline thereafter, except for the distal part of the arm. Range of motion was abnormal prior to operation and remained so after operation. Mean GMFM increase was 20% after 2 years (95% confidence interval 10-33); all five dimensions improved statistically significantly (P < 0.05). Mean PEDI increase was more than 20 scale points (95% confidence interval 10-35); again, all domains improved significantly (P < 0.05). In nearly all children, HARCES scores had normalized 2 years after surgery. In conclusion, decrease of seizure frequency and severity widens the scope of motor and social functioning, which overrides the effects of remaining motor impairments.

Alternative splicing of glutamate transporter EAAT2 RNA in neocortex and hippocampus of temporal lobe epilepsy patients

RATIONALE

Altered expression of glutamate transporter EAAT2 protein has been reported in the hippocampus of patients with temporal lobe epilepsy (TLE). Two alternative EAAT2 mRNA splice forms, one resulting from a partial retention of intron 7 (I7R), the other from a deletion of exon 9 (E9S), were previously implicated in the loss of EAAT2 protein in patients with amyotrophic lateral sclerosis.

METHODS

By RT-PCR we studied the occurrence of I7R and E9S in neocortical and hippocampal specimens from TLE patients and non-neurological controls.

RESULTS

Both splice forms were found in all neocortical specimens from TLE patients (100% I7R, 100% E9S). This was significantly more than in controls (67% I7R, 60% E9S; P < 0.05). We also detected I7R and E9S in all seven motor cortex post-mortem samples from patients with amyotrophic lateral sclerosis. Within the TLE patient group, both splice variants appeared significantly more in non-sclerotic (100%), than in sclerotic hippocampi (69%, P < 0.05).

CONCLUSION

These data indicate that the epileptic brain, especially that of TLE patients without hippocampal sclerosis, is highly prone to alternative EAAT2 mRNA splicing. Our data confirm that the presence of alternative EAAT2 splice forms is not disease specific.

Interrater agreement of the diagnosis and classification of a first seizure in childhood. The Dutch Study of Epilepsy in Childhood

OBJECTIVE

To assess the interrater agreement of the diagnosis and the classification of a first paroxysmal event in childhood.

METHODS

The descriptions of 100 first paroxysmal events were submitted to two panels each consisting of three experienced paediatric neurologists. Each observer independently made a diagnosis based on clinical judgment and thereafter a diagnosis based on predefined descriptive criteria. Then, the observers discussed all patients within their panel. The agreement between the six individual observers was assessed before discussion within each panel and after that, between the two panels.

RESULTS

Using their clinical judgement, the individual observers reached only fair to moderate agreement on the diagnosis of a first seizure (mean (SE) kappa 0.41 (0.03)). With use of defined descriptive criteria the mean (SE) kappa was 0.45 (0.03). The kappa for agreement between both panels after intra-panel discussion increased to 0.60 (0.06). The mean (SE) kappa for the seizure classification by individual observers was 0.46 (0.02) for clinical judgment and 0.57 (0.03) with use of criteria. After discussion within each panel the kappa between the panels was 0.69 (0.06). In 24 out of 51 children considered to have had a seizure, agreement was reached between the panels on a syndrome diagnosis. However, the epileptic syndromes were in most cases only broadly defined.

CONCLUSIONS

The interrater agreement on the diagnosis of a first seizure in childhood is just moderate. This phenomenon hampers the interpretation of studies on first seizures in which the diagnosis is only made by one observer. The use of a panel increased the interrater agreement considerably. This approach is recommended at least for research purposes. Classification into clinically relevant syndromes is possible only in a very small minority of children with a single seizure.

Diazepam-enhanced beta activity in Sturge Weber syndrome: its diagnostic significance in comparison with MRI

OBJECTIVES

This study was performed to assess the extent of functional involvement of the affected hemisphere in Sturge Weber syndrome in comparison with the uninvolved hemisphere. To this end beta activity in the electroencephalogram (EEG) was measured, both before and after administration of diazepam intravenously (i.v.).

METHODS

In 9 patients asymmetry in beta band activity was studied before and after diazepam administration. Several beta bands and asymmetry parameters were calculated. beta band asymmetries were compared with structural abnormalities (magnetic resonance imaging, MRI).

RESULTS

Total beta activity was reduced in the involved hemisphere in all patients after diazepam administration. In 3 patients functional abnormalities were found in brain regions that were structurally intact.

CONCLUSIONS

Decreased diazepam-enhanced beta activity in the EEG is a sensitive criterion of functional abnormality. In patients with subtle structural abnormalities diazepam-enhanced EEG may have added value in diagnosing functional involvement and in monitoring disease progression in patients.

Prevalence of cerebral palsy in The Netherlands (1977-1988)

Children with cerebral palsy (CP) and their families often make strong demands on diagnostic, therapeutic, technical and social facilities. Prevalence estimates are needed to improve treatment and services. As recent Dutch data are not available, the present study aimed to assess the population prevalence of CP in the Netherlands. A representative Dutch area with 1.2 million inhabitants of which 172,000 were born between 1977 and 1988 was studied. To ascertain the children with CP from these birth years, medical practices (such as rehabilitation centres, paediatric and child neurological departments) were consecutively asked to contact their (supposed) CP cases. Next, a parents' organisation and finally regional news media assisted in the ascertainment. In total, 170 'supposed' CP cases underwent an expert examination. Of these 170, 127 children proved to be definite CP-cases, yielding a 'crude' average prevalence of 0.74 per 1,000 inhabitants (95% CI: 0.61-0.87). Under-ascertainment was recognised and quantified. Accordingly, the population prevalence of CP over the birth year period 1977-1988 was calculated as 1.51 per 1,000 inhabitants (average over the 12 birth years). The calculated CP prevalence rose significantly over time: from 0.77 (1977-1979) to 2.44 (1986-1988). This trend is in accordance with other studies.

Breath holding spells in a 3-day-old neonate: an unusual early presentation in a family with a history of breath holding spells

Breath holding spells are common in childhood. They peak about 2 years of age and abate by 5 years of age; they are rare before 6 months of age. We report a case of cyanotic breath holding spells starting at the age of 3 days. There was a family history of breath holding spells including a three-year-old brother, patient's father, his sister, and the paternal great grandfather. Pharmacological intervention with iron replacement therapy and piracetam was not successful. We want to draw attention to the fact that breath holding spells should be included in the differential diagnosis of neonatal cyanotic spells. The course of these neonatal breath holding spells is thought to be "benign", but nevertheless, severe breath holding spells can pose problems for parents and clinicians.

The existence of two sources in rolandic epilepsy: confirmation with high resolution EEG, MEG and fMRI

In benign rolandic epilepsy seizure semiology suggests that the epileptic focus resides in the lower sensorimotor cortex. Previous studies involving dipole modeling based on 32 channel EEG have confirmed this localization. These studies have also suggested that two distinct dipole sources are required to adequately describe the typical interictal spikes. Since in benign epilepsy invasive validation is prohibited, this study tries to further establish these results using a multi-modal approach, involving 32 channel EEG, high resolution 84 channel EEG, 151 channel MEG and fMRI. From one patient interictal spikes were recorded and analyzed using the MUSIC algorithm in a realistic volume conductor model. In an fMRI experiment the same patient performed voluntary tongue movements, thus mimicking a typical seizure. Results show that EEC, MEG and fMRI localization converge on the same area in the lower part of the sensorimotor cortex, and that high resolution EEG clearly reveals two distinct sources, one in the post- and one in the pre-central cortex.

Distribution of glutamate transporters in the hippocampus of patients with pharmaco-resistant temporal lobe epilepsy

In patients suffering from temporal lobe epilepsy (TLE), increased extracellular glutamate levels in the epileptogenic hippocampus both during and after clinical seizures have been reported. These increased glutamate levels could be the result of malfunctioning and/or downregulation of glutamate transporters (also known as EAATs; excitatory amino acid transporters). In this study, the distribution of protein and mRNA of EAAT subtypes was examined in the hippocampus of TLE patients with hippocampal sclerosis (HS group) and without hippocampal sclerosis (non-HS group), and in autopsy controls without neurological disorders. EAAT protein localization was studied by immunohistochemistry on paraffin sections using specific poly- and monoclonal antibodies against the glial glutamate transporters EAAT1 and EAAT2 and the neuronal glutamate transporter EAAT3. Antibody specificity was shown by immunoblotting. In the HS group, a small decrease in EAAT1-immunoreactivity (IR) was observed in CA4 and in the polymorphic and supragranular layer of the dentate gyrus, compared with the control group. The strongest changes were found for EAAT2 levels. In the non-HS group, increased EAAT2-IR was detected in the CA1 and CA2 field, compared with non-epileptic controls. EAAT2-IR was decreased in the HS compared with the non-HS group. Fewer EAAT3-positive cells were found in the HS group than in the non-HS and control group. In both TLE groups, increased EAAT3 levels were observed in individual neurones. In the HS group, the percentage of EAAT3-IR neurones was increased in CA2 and in the granule cell layer of the dentate gyrus. Radioactive in situ hybridization for EAAT1-3 confirmed our immunohistochemical results. Non-radioactive in situ hybridization showed that not only astrocytes, but also neurones express EAAT2 mRNA. Taken together, differences in both mRNA and protein levels of glutamate transporter subtypes were found in specific regions in the TLE hippocampus, with most severe changes found for EAAT2 and EAAT3 levels. The results indicate an upregulation of EAAT2 protein expression in CA1 and CA2 in neurones in the non-HS group. This is in line with decreased EAAT2 protein levels in the HS group, since these hippocampi are characterized by severe neuronal cell loss. The functional consequences (glutamate transport capacity) of the reported changes in EAAT2 and EAAT3 remain to be determined.

The variety of visual perceptual impairments in pre-school children with perinatal brain damage

To study the selectivity of visual perceptual impairment in children with early brain injury, eight visual perceptual tasks (L94), were administered to congenitally disabled children both with and without risk for cerebral visual impairment (CVI). The battery comprised six object-recognition and two visuoconstructive tasks. Seven tasks were newly designed. For these normative data are presented (age 2.75-6.50 years). Because the recognition tasks required object naming, each item included a canonical control drawing and visual perceptual ability was evaluated relative to the non-verbal intelligence level, instead of chronological age. In 22 multiple disabled children with no indications of CVI, the frequency of impairment did not exceed that in the reference sample for any L94 task. In contrast, in 57 5-year-old children who were at risk for CVI due to pre-maturity or birth asphyxia, a significant increase in the frequency of impairment was seen on six L94 tasks (range 12-38%). However, only five children had more than two impairments, indicating that the deficits were selective, not pervasive. We conclude that early brain lesions interfere with the functioning of particular visual subsystems, yet leave other subsystems intact and functioning within the normal range.

Neuromuscular scoliosis: clinical evaluation pre- and postoperative

Neuromuscular scoliosis concerns a wide variety of disorders, all with a different approach to surgical intervention. The impact of these disorders on a patient is discussed in terms of pulmonary, cardiac, bowel and bladder function and complications in the perioperative and postoperative period such as gastric ulcers, pathologic fractures, wound healing, and nutrition is described. These difficult patients need a multidisciplinary approach. The 'Utrecht team' set-up is described in an 'as we do it' way. Items on preoperative clinical and radiological examination are provided, as well as points of special attention in perioperative care. Early detection, decision-making and intervention makes it possible to correct and stabilize the spine in these children with a short stay in hospital and a quick recovery.

Relation between visual perceptual impairment and neonatal ultrasound diagnosis of haemorrhagic-ischaemic brain lesions in 5-year-old children

Visual-perceptual abilities were assessed in 5-year-old children with the following neonatal neurological conditions: born preterm with normal ultrasound scan (NL, n=17); born preterm with ultrasound diagnosis of intraventricular haemorrhage (IVH, n=17); born preterm with ultrasound diagnosis of periventricular leukomalacia (PVL, n=12); born term with hypoxic-ischaemic encephalopathy (HIE, n=11). Visual-perceptual ability was evaluated with the L94: eight visual-perceptual tasks designed to evaluate different aspects of visual perception at the preschool level in children with multiple disabilities. Impairment was established in comparison to the performance age obtained on non-verbal intelligence subtests, instead of chronological age. Frequency of L94 impairment was highest in children with PVL, while children with IVH did not differ from the NL control group. Impairment rates were increased also in children with transient periventricular echodensities, and in children with HIE. Impairments were only moderately related to the delay of visual acuity maturation in infancy.

Fetal pain?

During the last few years a vivid debate, both scientifically and emotionally, has risen in the medical literature as to whether a fetus is able to feel pain during abortion or intrauterine surgery. This debate has mainly been inspired by the demonstration of various hormonal or motor reactions to noxious stimuli at very early stages of fetal development. The aims of this paper are to review the literature on development of the pain system in the fetus, and to speculate about the relationship between "sensing" as opposed to "feeling" pain and the number of reactions associated with painful stimuli. While a cortical processing of pain theoretically becomes possible after development of the thalamo-cortical connections in the 26th week of gestation, noxious stimuli may trigger complex reflex reactions much earlier. However, more important than possible painfulness is the fact that the noxious stimuli, by triggering stress responses, most likely affect the development of an individual at very early stages. Hence, it is not reasonable to speculate on the possible emotional experiences of pain in fetuses or premature babies. A clinically relevant aim is rather to avoid and/or treat any possibly noxious stimuli, and thereby prevent their potential adverse effects on the subsequent development.

Subcortical laminar heterotopia in two sisters and their mother: MRI, clinical findings and pathogenesis

MR imaging, clinical data and underlying pathogenesis of subcortical laminar heterotopia (SCLH), also known as band heterotopia, in two sisters and their mother are presented. On MR imaging a different degree of SCLH was found in all three affected family-members. The inversion recovery sequence was considered most useful in the demonstration of the heterotopic band of gray matter and the assessment of cortical thickness. The younger sister presented with epileptic seizures at the age of five months and a delayed achievement of developmental milestones. The older sister of seven years had epileptic seizures since the age of one year, and developmental delay. Their mother has only had one seizure-like episode at the age of 39. Her psychomotor development had been normal. Investigation of DNA samples of the three female family-members revealed a mutation in the X-linked doublecortin gene. Within families with band heterotopia, this gene has also been related to male family members with lissencephaly.

Malignant pancreatic tumour within the spectrum of tuberous sclerosis complex in childhood

A 12-year-old boy with tuberous sclerosis complex (TSC) presented with a large retroperitoneal tumour. Exploratory surgery revealed an infiltrative tumour originating from the pancreas, with local metastases to the lymph nodes. The histologal diagnosis was a malignant islet cell tumour. Retrospectively measured pancreatic hormone levels, however, were normal. A connection between the malignancy and TSC was demonstrated by loss of heterozygosity of the TSC2 gene in the tumour. The primary mutation Q478X in this patient was identified in exon 13 of the TSC2 gene on chromosome 16.

CONCLUSION

Pancreatic islet cell tumours have been mainly associated with multiple endocrine neoplasia syndrome type 1. In our case we demonstrate a direct relationship of this tumour to tuberous sclerosis complex, in the absence of further signs of multiple endocrine neoplasia syndrome type 1.

Influence of infant-walkers on motor development: mimicking spastic diplegia?

We discuss two patients, who used an infant walker during the period in which they learned to walk. The influence on qualitative and quantitative motor development is illustrated in this report. A disharmonic and delayed motor development, contractures of the calf-muscles and motor development mimicking spastic diplegia are considered to be caused by the early use of infant walkers. As illustrated by the literature, infant walkers do not have any positive effect on improving motor development. Vulnerability of infants with regards to accidents is increased. In our opinion, the use of infant-walkers should be discouraged.

Development of visual function in hemihydranencephaly

This study reports on the findings of longitudinal follow-up of visual function in a 12-year-old girl affected by congenital right hemihydranencephaly. This extremely rare unilateral brain malformation allowed the authors to gather new information on neuronal plasticity and functional compensations of the visual system across a period of 10 years. An extension of the preserved right visual hemifields above the middle line and strategical eye or head positions developed to increase visual functions are discussed. In addition, ophthalmological and orthoptical findings, as well as the development of monocular grating and linear acuity, are described.

Performance of 5-Year-Old Children on Seven Visual Perceptual Tasks in Relation to Neonatal Ultrasound Abnormalities

We investigated whether neonatal brain damage can give rise to visual perceptual deficits, in addition to the well-documented impairments in visual acuity. To this end, forty-one children (age 5.02 to 5.89 years) were given four visual object identification tasks and three visuo-constructive tasks. These subjects were neonatal at risk owing to prematurity or birth asphyxia. From neonatal ultrasound scans, the occurrence of intracranial hemorrhage (ICH, N = 17), periventricular leukomalacia (PVL, N = 15), and/or white matter damage due to either of these conditions (WMD, N = 9) was determined for each subject. Scans were normal in fourteen of them. The number of subjects performing at or below Pc10 of same-age normal children was significantly above 10% for each task (range 27% – 49%). This was still true when mental instead of chronological age was used for comparison, as shown by the results of nine subjects for which intelligence data were available. This high incidence of impairment is not attributable to loss of visual acuity, since grating acuity was reduced in only four subjects (14 – 19 cycles deg−1). The frequency of scores < Pc10 correlated significantly with WMD in six tasks, with PVL in 4 tasks, but not with ICH. We conclude that neonatal at risk children are more likely to develop impaired visual perceptual skills, independent of mental disability and visual acuity loss. On ultrasound permanent white matter abnormalities are most strongly associated with visual perceptual deficit, whereas intracranial hemorrhage is unrelated.

Early predictors of cerebral visual impairment in infants with cystic leukomalacia

A longitudinal prospective follow-up study looking at the correlation between haemorrhagic-ischaemic lesions on neonatal cranial ultrasound (US) and the development of cerebral visual impairment (CVI) in infancy resulted in the detection of nine infants with severe visual impairment, which was not due to opthalmological abnormalities. Extensive cystic leukomalacia proved to be highly predictive of CVI, as well as of severe mental and motor deficit in these nine infants. The present report outlines the results of different examinations (acuity card procedure [ACP], visual evoked potential [VEPs], magnetic resonance imaging [MRI]) performed during the first 18 months, to find out which combination of examinations would be the most predictive of CVI at an early stage. The results indicated that infants with a gestational age of 35 weeks or more, who sustained extensive cystic leukomalacia during the neonatal period, and were subsequently not fixating at the acuity cards at term and at three months of age, invariably developed CVI. VEPs were also severely abnormal in the infants with the worst visual outcome, but were not providing a more reliable prognosis. Also, a good correlation between MRI-abnormalities of the optic radiations and/or the visual cortex and CVI was found, but MRI was usually performed beyond the age of 12 months.

Long term ocular and neurological involvement in severe congenital toxoplasmosis

AIMS

This study was set up to determine the long term ocular and systemic sequelae in patients with severe congenital toxoplasmosis.

METHODS

Cross sectional and retrospective study of 17 patients with severe congenital toxoplasmosis.

RESULTS

In addition to chorioretinitis (100%), the most common abnormal ocular features were optic nerve atrophy (83%), visual acuity of less than 0.1 (85%), strabismus, and microphthalmos. In 50% of cases we observed iridic abnormalities and about 40% developed a cataract. Overt endocrinological disease, diagnosed in five of 15 patients, included panhypopituitarism (n = 2), gonadal failure with dwarfism (n = 1), precocious puberty with dwarfism and thyroid deficiency (n = 1), and diabetes mellitus and thyroid deficiency (n = 1). The observed endocrinological involvement was associated in all cases with obstructive hydrocephalus with a dilated third ventricle and optic nerve atrophy.

CONCLUSION

The recognition of long term ocular, neurological, and endocrinological sequelae of congenital toxoplasmosis is important for medical management of these severely handicapped patients.

Leukoencephalopathy with swelling and a discrepantly mild clinical course in eight children

An identical syndrome of cerebral leukoencephalopathy and megalencephaly with infantile onset was discovered in 8 children, including 2 siblings. Neurological findings were initially normal or near normal, despite megalencephaly and magnetic resonance imaging (MRI) evidence of severe white matter affection. Slowly progressive ataxia and spasticity developed, while intellectual functioning was preserved for years after onset of the disorder. MRI characteristics included diffuse abnormality in signal intensity and swelling of the cerebral hemispheral white matter with cyst-like spaces in the frontoparietal and anterior-temporal subcortical areas. MR spectra were relatively mildly abnormal. Screening for inborn errors, especially those that cause either megalencephaly or white matter disease or both was negative. A distinguishing feature of the present disorder is the apparently severe abnormality of the cerebral white matter as demonstrated by MRI, which contrasts with the remarkably slow course of functional deterioration.

Haemorrhagic-ischaemic lesions of the neonatal brain: correlation between cerebral visual impairment, neurodevelopmental outcome and MRI in infancy

The relationship between the degree of cerebral visual impairment, established using the acuity card procedure, and the extent of neurological sequelae was assessed in 65 at-risk neonates in a prospective follow-up study. MRI and CT scans were performed in all infants with severe neurological sequelae. 11 of 12 children with an acuity at or below the 10th centile at 18 months developed cerebral palsy: the underlying condition was extensive cystic leukomalacia in all. An acuity above the 10th centile was no guarantee of normal development, as 10 out of 52 such infants developed cerebral palsy. MRI and CT scans showed that periventricular high signal intensity in the occipital area was a non-specific finding with regard to visual function. Extensive periventricular white matter loss and involvement of the striate/parastriate cortex was found in the most severely visually impaired infants.

Cerebral visual impairment in cerebral palsy: relation to structural abnormalities of the cerebrum

In patients with cerebral palsy (CP), cerebral visual impairment (CVI) is frequently found in addition to ophthalmological disorders. Lesions in the visual areas are found in CT scans of CP patients with CVI. The aim of the present study was to determine the prevalence of these specific findings in CP patients with CVI. CT scans of 49 cerebral palsy patients were studied; CVI was diagnosed in 36 patients; in 13 patients, visual acuity was normal. In 8 patients, comparison with an MRI scan was possible (6 with CVI, 2 with normal acuity). The CT scans were scored according to the criteria used by Van Nieuwenhuizen (1987): normal, abnormalities of the white matter adjacent to the posterior horns of the lateral ventricles, abnormalities of the white matter located under the visual cortex, abnormalities of the visual cortex and abnormalities elsewhere. Abnormalities in the visual areas were found in 15% of the normal acuity group and in 53% of the CVI group. In 17 of the 19 CVI patients with abnormalities in the visual areas, the lesions were located in the white matter surrounding the posterior horns (89%). MRI imaging revealed the same abnormalities as the CT scans in 6 patients, but in one patient the abnormality was seen in more detail and in one patient the lesion in the occipital area was seen only on MRI. MRI examination seems to detect at least as many, but in some cases even more specific lesions in CVI patients compared to CT scanning, but the numbers were too small to allow any definitive conclusions to be drawn.

Relation between neonatal cranial ultrasound abnormalities and cerebral visual impairment in infancy

A prospective follow-up study was conducted of a cohort of 65 at-risk neonates to assess the predictive value of neonatal cranial ultrasound abnormalities for cerebral visual impairment in infancy. Visual function was assessed using the acuity card procedure and behavioural visual responses were tested. Normal visual function was found in controls as well as in infants with small haemorrhages or mild leukomalacia. Infants with large haemorrhages performed poorly at 40 weeks postmenstrual age, but recovered to within the normal range in the first half year. In contrast, of the infants with extensive cystic leukomalacia, four of nine preterm infants and three of four term infants were severely visually impaired at 18 months. In the more mature infants, the cystic lesions extended deeper into the subcortical white matter, and this appeared to be associated with a worse visual outcome. Cystic leukomalacia proved to be highly predictive of cerebral visual impairment in infancy.

The effect of non-depot ACTH(1-24) on infantile spasms

However, side-effects such as severe infections, hypertension and electrolyte imbalance have been found, assumed to be related to hypercortisolism induced by chronic ACTH treatment. The authors treated 18 patients with infantile spasms with non-depot ACTH(1-24). The therapeutic effect of non-depot ACTH was comparable to that of depot ACTH, with no severe bacterial infection or sepsis. The incidence of hypertension was significantly lower in the non-depot ACTH group, and persistent hypercortisolaemia was not found. Non-depot ACTH(1-24) appears to be as effective as ACTH(1-24) depot therapy in the treatment of infantile spasms, and its side-effects are mild. It would appear that the effect of non-depot ACTH is not mediated by hypercortisolism, but by a direct neurotropic effect on the brain.

Mycotic encephalitis: predilection for grey matter

In mycotic infections of the brain three patterns of abnormality may be observed: meningitis, granuloma, and encephalitis. The first two, consisting of diffuse meningeal enhancement and mass lesion respectively, can easily be visualised by CT or MRI, but are nonspecific. The third pattern has been described histopathologically; as the clinical picture is nonspecific and the diagnosis is often unsuspected, especially in immunocompetent patients, acquaintance with the characteristic CT and MRI patterns of mycotic encephalitis may help in establishing the correct diagnosis, with important therapeutic consequences.

Grating-acuity in children. Normal values of visual acuity in children up to 13 years as assessed by the acuity card procedure

The acuity card procedure proved to be a useful method for assessing visual acuity in children. Normal values of visual acuity measured by this method had already been assessed in children up to four years. To enable application of the test in older children this study obtained values in a group of 396 normal children, aged three months to 13 years. The mean curve as well as the 10th centile was calculated in different age groups. A considerable variation of acuity values causing a 'dip' in the 10th centile was found in the ages 18 to 24 months. A smaller 'dip' was found in the ages 48 to 52 months. This has to be attributed to behavioural properties connected with age. The results obtained in the group of children under four years of age corresponded fairly well with other studies. In schoolchildren a fair agreement could also be found between the data obtained using the acuity card procedure and the data obtained with the Landolt-C rings. Obtaining normal values for the acuity card procedure in children covering a wide age range facilitates recognition of visual handicap in children who are difficult to assess.

The prevalence of cerebral visual disturbance in children with cerebral palsy

Assessment of visual acuity using the visual acuity card procedure in 164 children with cerebral palsy revealed low visual acuity in 71 per cent. Results of ophthalmological examination were available for 74 of these patients, but could not explain adequately the low visual acuity of 36 of the 43 patients (84 per cent) assessed by both the acuity card procedure and other techniques. There is a high probability that cerebral visual disturbance is present in these patients. Awareness of visual disability when compiling a programme of visual and neurodevelopmental stimulation for children with cerebral palsy is essential.