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O Delalande

Publications and source records attributed to O Delalande.

At least 19 recordsLinked to original sources
PubMed2005

[Recent advances in pathogenic concepts and therapeutic strategies in Rasmussen's encephalitis].

Rasmussen's encephalitis (RE) is a rare inflammatory brain disease mainly affecting children and characterised by intractable epilepsy involving a single hemisphere that undergoes progressive atrophy. RE is characterized by refractory focal seizures, often associated with epilepsia partialis continua, progressive unilateral motor defect, slow EEG activity over the entire contralateral hemisphere, with focal white matter hyperintensity and insular cortical atrophy on neuroimaging. Surgical exclusion of the affected hemisphere is the only treatment that interrupts progression of the disease. Pathogenic concepts have considered viruses, autoimmune antibodies and autoimmune cytotoxic T lymphocytes that might contribute to the initiating or perpetuating events in the central nervous system. Based on these concepts, different therapeutic strategies have been pursued, such as antiviral agents, plasmapheresis, immuno-adsorption, immunosuppression or immunomodulation with intravenous immunoglobulins. However, due to the lack of large studies, to date there is no established therapeutic strategy for this devastating condition. In this review, we give an overview of the current state of immunopathogenic concepts for Rasmussen's encephalitis and discuss the different therapeutic options for future perspectives.

Early Diagnosis↗
PubMed2004

Behavioural epileptic seizures: a clinical and intracranial EEG study in 8 children with frontal lobe epilepsy.

We report on eight children who underwent prolonged invasive video-EEG recording (IC-EEG) for intractable frontal lobe epilepsy and whose seizures consisted of behaviour changes. Seizures were recorded on a BMSI computer with 128 channels connected to the Gotman software of a stellate system; their identification was made both clinically and by automatic detection of paroxysmal electrical events. Behavioural epileptic seizures (BES) consisted of various clinical signs comprising mood change, sudden agitation, unexpected quietness, and subtle change of awareness or awakening. In 2 patients, seizures consisted in repetitive movements that we referred to as epileptic stereotypes. BES came from the prefrontal areas of the brain. Most of them were overlooked or misdiagnosed as behavioural manifestations, especially in children with mental deficiency and autistic features. Given the improvement of behaviour and mental functions following surgery, we assume that BES may contribute to generate mental and behavioural dysfunction.

Autistic Disorder↗
PubMed2004

[Surgery for intractable focal epilepsy in children].

Surgery of drug resistant epilepsy in children is a functional surgery which aims at the suppression of the epileptogenic focus. The surgical decision is adopted or rejected as a result of the clinical examination and complementary investigations following a multidisciplinary discussion in which the benefit-risk ratio is being carefully weighed. The objective of the presurgical investigations, dominated by scalp-recorded video-electroencephalography and magnetic resonance imaging, is the localization of the epileptogenic focus. The invasive surgical investigations with intracranial electrode placement are indicated when the limits of a planned resection have to be defined precisely or when the focus is located nearby a functionally eloquent region (sensori-motor and language region). Their identification is possible by means of electrical stimulation. Two methods of exploration are available: The combination of subdural and intracerebral electrode placement through craniotomy and the stereotactic placement of intracerebral depth electrodes (Stereo-EEG). The choice of either of these two methods depends on the child's age and on the topography of the epileptogenic focus. Surgery can be either palliative, with the purpose of reducing the intensity and/or the frequency of a certain seizure type (callosotomy, multiple subpial transsections) or curative, aiming at a suppression of the epileptogenic focus through a resective or a disconnective surgical procedure. We have operated on a population of 148 children and infants between 3 months and 10 years of age during the years 1993 to 2001: In the infant group, dysplastic lesions represented the predominant etiology. In the age group of 3 to 10 years, the underlying pathology was more distributed (dysplastic lesions, epileptogenic tumors, Rasmussen's encephalitis, hypothalamic hamartomas). Extratemporal focal resections required, in the majority of cases, an invasive preoperative exploration and hemispherotomy was frequent in this group (44 p. 100). Sixty-seven percent of the children were seizure-free, with an acceptable morbidity rate, primarily due to shunt placement following hemispherotomy in children with dysplastic lesions. Our preliminary results concerning quality of life and socialization are encouraging and favor surgical treatment at an early stage.

Anticonvulsants↗
PubMed2003

Ictal SPECT in children with epilepsy: comparison with intracranial EEG and relation to postsurgical outcome.

In order to validate the ability of ictal single photon emission computed tomography (SPECT) to localize the epileptogenic zone (EZ) in children, we compared in 20 patients aged from 10 months to 17 years (mean 6.5 years) the topography of the area of increased ictal perfusion (IPA), determined on the basis of ictal minus interictal scan values, with that of the EZ determined by intracranial EEG recordings and assessed its relationship with the postsurgical outcome. Eighteen patients had symptomatic epilepsy and 10 had extratemporal epilepsy. All patients except one had an ictal injection (mean time lag from clinical seizure onset was 18 s). Ictal and interictal SPECT images were successively co-registered, normalized, subtracted, smoothed and superimposed on MRI. All patients with ictal injection exhibited one or several IPAs. The topography of the 'highest' IPA, i.e. the maximal cerebral blood flow (CBF) change between ictal and interictal SPECT, significantly colocalized with the site of onset of the discharge, and that of the lower IPAs with that of the area of propagation (P < 0.0001). At a threshold of 30% of the maximal CBF change, the IPAs detected the onset of the discharge with a sensitivity of 0.80 and a specificity of 0.70. The highest IPA localized the EZ in 12 out of 15 patients. In the three others it missed the EZ and showed the area of propagation because of rapid seizure propagation or of infraclinical seizure onset. Among the patients with favourable surgery outcome, the highest IPA colocalized with the resected area in 70% of cases. Ictal SPECT could therefore plays an important role as a non-invasive presurgical method of investigation by optimizing the placement of intracranial electrodes, thus improving the postsurgery outcome of paediatric partial epilepsy.

Adolescent↗
PubMed2002

Docking study of cistanoside C to telomeric DNA fragment.

Experiments show that the natural products phenyl propanoid glycosides (PPGs) extracted from the plant Pedicularis spicata are capable of repairing DNA damaged by oxygen radicals. Based on kinetic measurements and experiments on tumor cells, a theoretical study of the interaction between PPG molecule Cistanoside C and telomeric DNA fragment has been carried out. The docking calculations performed using JUMNA software showed that the Cistanoside C could be docked into the minor groove of telomeric DNA and form complexes with the geometry suitable for an electron transfer between guanine radical and the ligand. Such complexes can be formed without major distortions of DNA structure and are further stabilized by the interaction with the saccharide side-groups.

Catechols↗
PubMed1999

Callosotomy for epilepsy after West syndrome.

PURPOSE: To analyze the results of callosotomy in 17 children with symptomatic generalized epilepsy after West syndrome, according to the different seizure types and surgical procedures, to define selection criteria for candidates to callosotomy. METHODS: Callosotomy was performed in two successive stages. Partial callosotomy, anterior in 13 and posterior in three, was followed by completion in 14 cases in all but four patients (complete callosotomy in one stage in one, no completion in three). All patients had clinical, video-EEG, and neuropsychological evaluation before and after each stage of callosotomy, with a mean final follow-up of 4 years. RESULTS: Seizure frequency improved in only two of 13 patients after anterior callosotomy, in none of three after posterior callosotomy, but in nine of 14 after complete callosotomy. After complete callosotomy, spasms disappeared in 80% of the cases, and drop attacks, the most severe ictal event, completely stopped or were dramatically reduced in 90% of the children. One patient no longer had episodes of status epilepticus, and another one acquired the ability to walk after complete callosotomy. From the cognitive viewpoint, nine patients with improved seizure frequency after complete callosotomy also had improved behavior and cognitive functions, but two others experienced speech deterioration after posterior callosotomy at age 11 years and completion of callosotomy at age 16 years. CONCLUSIONS: As in other severe generalized epilepsies in childhood, drop attacks provide the best indication for complete callosotomy in patients with previous West syndrome. Because drop attacks can be identifiable by falls only, the previous acquisition of walking should be considered as a key feature for any benefit to be obtained.

Child↗
PubMed1999

Early diagnosis of subependymal giant cell astrocytoma in children with tuberous sclerosis.

OBJECTIVES: Intraventricular astrocytomas (subependymal giant cell astrocytomas) of tuberous sclerosis have a poor prognosis due to the obstruction of CSF flow. The aim of this study was to determine whether they could be differentiated during childhood and at an early preclinical stage, from subependymal nodules without any growing potential. METHODS: The first two MRIs of all children referred to this neuropaediatric centre between 1987 and 1996 were retrospectively blindly reviewed. RESULTS: Out of 60 patients, 24 disclosed subependymal nodules localised near the foramen of Monro, and eight of the 24 developed astrocytomas. Subependymal nodules were first detectable on MRI from 1 year of age in all cases and the first MRI evidence of growth occurred between 1 and 9 years (mean 4 years). At an early stage, subependymal nodules had different characteristics in patients who developed subependymal giant cell astrocytomas from those who did not. The nodules over 5 mm in diameter that were incompletely calcified and enhanced by gadolinium were at higher risk of growing, particularly in children with a familial history of tuberous sclerosis. To detect the subependymal giant cell astrocytomas earlier in tuberous sclerosis, it is advisible to systematically perform an MRI examination before 2 years of age and to repeat it every year if the patient has risk factors for developing astrocytomas.

Brain Neoplasms↗
PubMed1998

Focal cortical dysplasia and hemimegalencephaly: histological and neuroimaging correlations.

BACKGROUND: The classification of cerebral cortical dysplasia is difficult and there are histological similarities between focal cortical dysplasia (FCD) and hemimegalencephaly. Objectives. To correlate the MR features and histological data of cortical dysplasias. MATERIALS AND METHODS: The MR appearances of 17 brains were examined. According to the signal intensity within the pathological area on T2-weighted (T2-W) sequences we selected two groups. RESULTS: Group 1 comprised ten patients with high signal in the dysplastic area on T2-W images. This group included five hemimegalencephalies, three frontal quadramegalencephalies, and one gyral dysplasia. The pathological hemisphere was reduced in size in one case. The cortex was thickened in all cases on T1-weighted (T1-W) images. There was loss of delineation between white matter (WM) and grey matter (GM) in all cases on both T1-W and T2-W sequences. The differential diagnosis with tumour, neoplastic-like malformation or polymicrogyria was questionable. Group 2 comprised seven patients presenting without increased signal within the dysplastic area on T2-W images. WM and GM were of similar signal intensity in six cases, and delineation between white and grey matter was absent in all cases. There were mild abnormalities on T1-W sequences in all cases. The dysplasias were limited to a lobe in five cases and a gyrus in two cases. In all cases, depiction of the malformation was a greater diagnostic problem than the differential diagnosis. CONCLUSIONS: A constant MR sign in our series was the loss of delineation between WM and GM in the dysplastic area. This correlated well with the observed histological disorganisation. Markedly high signal within the dysplastic area seems to be related to myelin abnormalities rather than glial cell abnormalities.

Adolescent↗
PubMed1998

[Surgery and epilepsy].

Corpus callosotmy was introduced in 1940 as a palliative treatment for generalized epilepsies. The improvement of the surgical technique, and the simplification of the initial "total commissurotomy" made that procedure proposed in order to decrease the frequency and the severity of the seizures occurring in the secondary geralzed epilepsies. However the indication criteria remain unclear, due to the difficulty for analysing the results and the feterogenity of the series. A careful selection requiring a comprehensive epilepsy team remains mandatory despite the relative simplicity of the procedure.

Brain Diseases↗
PubMed1997

Chiari I malformation associated with syringomyelia and scoliosis.

STUDY DESIGN: A retrospective review of a series of 12 children who underwent suboccipital foraminotomy and duroplasty for Chiari I malformation. OBJECTIVE: To assess the effects of this surgery on associated syringomyelia and scoliosis. SUMMARY OF BACKGROUND DATA: Suboccipital foraminotomy for the treatment of syringomyelia associated with Chiari I malformation was greatly stimulated by Gardner's hydrodynamic theory, and its results proved to be encouraging. However, several authors reported improvement or stabilization of associated scoliosis after this surgery. METHODS: A retrospective review was conducted on 12 patients who underwent suboccipital foraminotomy for Chiari I malformation associated with syringomyelia. Neurologic Impairment, extent of syringomyelia, and severity of associated spinal deformity were assessed preoperatively and at a 4.5-year average follow-up (range, 2.1-12 years). Anomaly of superficial abdominal reflexes was found in all cases, and para or tetraparesis in three cases. Syringomyelia was of variable localization and extent. Scoliosis was present in 7 cases (greater than 40 degrees in 5 cases). RESULTS: Diminution or complete disappearance of syringomyelia was observed in 11 cases, 3 months to 1 year after surgery. Superficial abdominal reflexes anomaly improved in four cases. Minimal neurologic deficit persisted in one case. Scoliosis improved in one case, remained unchanged in one case, and progressed in the five cases with preoperative severe deformity, requiring instrumentation and fusion. CONCLUSIONS: Improvement of syringomyelia and neurologic deficit, observed with suboccipital foraminotomy, supports the theory that abnormal hydrodynamics of the cerebral spinal fluid is most likely to cause these deficits.

Adolescent↗
PubMed1997

[Late cerebral radionecrosis of cystic aspect].

Two cases of delayed cerebral radionecrosis with cystic presentation are reported. The patients had received radiation therapy for a cutaneous tumor 16 and 12 years before. Surgical extirpation of the cerebral lesion permitted to confirm the diagnosis and to treat the patients with success. A cystic aspect has been reported rarely in the neuroradiologic descriptions of the cerebral radionecrosis in the literature. Its mechanism is discussed. The treatment of the delayed cerebral radionecrosis is not clearly established, but a cystic presentation is an argument for surgery.

Adult↗
PubMed1996

[Problems related to neurosurgical treatment of epilepsy in children].

Neurosurgery of epilepsy in children has undergone rapid development during the past decade. This was justified by the high incidence of intractable epilepsy and its consequences on cognitive development. Any decision in the area of surgery must take in account specific etiology and the rapid maturation of the infant's brain. As in adulthood, both the epileptogenic and the functional zones must be identified, but this is a challenge when the brain is not mature and the functions not yet developed. In addition, the ability to recover must be determined. At the present time no precise methodology can be advised for presurgical work-up and surgical indications.

Age Factors↗
PubMed1994

Transsphenoidal surgery for pituitary adenomas in children.

The authors have reviewed the results of transsphenoidal surgery for pituitary adenomas done on 66 children (younger than 16 yr of age) between 1966 and 1992. Ninety-four percent (62 of 66) showed clinical evidence of pituitary hormonal hypersecretion. The most common type was the adrenocorticotropic hormone-secreting adenoma (n = 36), followed by the prolactinoma (n = 18) and the growth hormone-secreting types (n = 8). There were four cases of nonfunctioning adenomas. Adrenocorticotropic hormone-secreting tumors in children had presentations and surgical results similar to those seen in adults. Twenty-three of 33 patients with Cushing's disease had simple adenomectomy or subtotal hypophysectomy without symptomatic recurrence. Four of 10 initial treatment failures had subsequent successful surgical intervention, resulting in an overall cure rate of 78%. Postoperative hypocortisolism was suggestive of surgical success but was not absolute. Of three patients with Nelson syndrome, none were successfully treated with surgery alone and two developed invasive disease. Prolactin-secreting and growth hormone-secreting tumors in children occurred more commonly with suprasellar expansion than did their adult counterparts. Transsphenoidal surgery was capable of controlling disease in only 12% (1 of 8) of growth hormone-secreting tumors, and 67% (12 of 18) of prolactin-secreting tumors required postoperative medical therapy or radiotherapy for persistently elevated prolactin levels. Special difficulty was noted in boys with prolactinomas and in girls with primary amenorrhea. As in adults, preoperative prolactin levels correlated with ultimate surgical success rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗