Exploring Memory Systems After Pediatric Posterior Fossa Tumor: From Memory Profile Comparisons in Nonirradiated Versus Irradiated Patients to Episodic Memory Tests Capable of Detecting Radiation-induced Hippocampal Damage.

AIMS: Pediatric posterior fossa tumor (PFT) survivors experience long-term cognitive sequelae, including memory disorders, for which irradiation is one of the main risk factors. The aims of the present study were to (1) explore the profile of impairment in episodic, semantic, working and procedural memory systems in irradiated versus nonirradiated PFT survivors, and (2) test whether an autobiographical questionnaire and a two-phase ecological test (Epireal) assessing episodic memory are more sensitive to radiation-induced hippocampal damage than commonly used tests. MATERIALS AND METHODS: A total of 60 participants (22 irradiated PFT survivors, 17 nonirradiated PFT survivors, and 21 controls) were included in the prospective IMPALA study. They all underwent a broad battery of tests assessing the different memory systems in two 2-day sessions 3 weeks apart. We performed between-groups comparisons and analyzed impairment profiles, using -1.65 SDs as a cut-off. For irradiated patients, correlations were calculated between mean radiation doses to key brain structures involved in memory (hippocampus, cerebellum, and striatum) and corresponding memory scores. RESULTS: PBT survivors performed significantly more poorly than controls (p < 0.001) on conventional tests of episodic, semantic and working memory: 64% of irradiated patients and 35% of nonirradiated patients had a deficit in at least two memory systems, with episodic memory impairment being more specific to the irradiated group. Epireal had a larger effect size than the other episodic memory tests, allowing us to detect deficits in a further 18% of irradiated patients. These deficits were correlated with the mean radiation dose to the left hippocampus. CONCLUSION: Memory impairment is a frequent long-term cognitive sequela in PFT survivors, especially after radiation therapy. New ecological tests of episodic memory that are more sensitive to radiation-induced deficits than conventional tests could yield specific markers of the toxicity of medial temporal lobe irradiation.

A Prospective Study of Arterial Spin Labelling in Paediatric Posterior Fossa Tumour Survivors: A Correlation with Neurocognitive Impairment.

AIMS: Posterior fossa tumours (PFTs), which account for two-thirds of paediatric brain tumours, are successfully treated in about 70% of patients, but most survivors experience long-term cognitive impairment. We evaluated arterial spin labelling (ASL), a common, non-invasive magnetic resonance imaging (MRI) technique, as a biomarker of cognitive impairment in a paediatric PFT survivor population. MATERIALS AND METHODS: Sixty participants were prospectively analysed. PFT survivors were at least 5 years post-treatment and had been treated as appropriate for their age and type of tumour. Group 1 had received radiotherapy and Group 2 had not. Group 3 were healthy controls matched to Group 1 for age, sex and handedness. All participants underwent cognitive assessment and multimodal MRI, including an ASL perfusion sequence. We used semi-quantitative ASL methods to assess differences in mean perfusion in the thalamus, caudate, putamen and hippocampus. RESULTS: Statistically, no significant associations between cognitive data and radiation doses were identified. Compared with healthy controls, Group 1 patients had significantly lower overall mean perfusion values (20-30% lower, depending on the cerebral structure) and Group 2 had slightly lower mean perfusion values (5-10% lower). Perfusion values did not correlate with total prescribed irradiation doses nor with doses received by different cerebral structures. Episodic and semantic memory test scores were significantly lower in Group 1 and correlated with lower mean absolute perfusion values in the hippocampus (P < 0.04). CONCLUSIONS: These preliminary results indicate that radiotherapy affects the perfusion of specific cerebral structures and identify perfusion as a potential biomarker of hippocampus-dependent memory deficit.

[Treatment and prognosis of idiopathic intracranial hypertension in children. Retrospective study (1995-2009) and literature review]. / Traitement et pronostic de l'hypertension intracrânienne idiopathique de l'enfant. Étude rétrospective (1995-2009) et revue de la littérature.

AIM: Idiopathic intracranial hypertension (IIH) may cause severe visual loss due to the optic nerve damage. Routine management involves mainly medical treatment. The aim of this study was to improve diagnosis and management of IIH in children. METHODS: The medical records of all patients with definite IIH seen at the children's hospital of Toulouse between 1995 and 2009 were reviewed. Cases of secondary intracranial hypertension were included because they did not present any cerebral lesions and underwent a similar therapeutic approach. The clinical and ophthalmological data at the beginning and at the end of their treatment was collected. RESULTS: Eighteen children were included in this study. The average age was 10 years and the sex-ratio was equal to 1. There were 3 cases of secondary idiopathic intracranial hypertension in this pediatric group. The main features encountered were headache (15 children) and diplopia (8 children). Abnormal neurological examination was found for 11 patients with abducens nerve paresis in 8 cases, rachialgia in 6 cases, and neurogenic pains (neuralgia, dysesthesia, paresthesia, hyperesthesia) in the other cases. Papilledema was noted in 16 patients. At the initial phase, loss of visual acuity was documented in 6 patients and altered visual field in nine patients. All patients had a medical treatment. When recurrence occurred, each new treatment was documented, for a total of 23 treatments analyzed. Lumbar puncture was the only treatment for 2 patients. In 16 cases, first-line treatment was acetazolamide and it was the second choice in 1 case, with an average dosage of 11.2mg/kg and a mean duration of 2.5 months (15 treatments could be analyzed). This treatment was effective in 11 cases out of 15. Steroids were the initial treatment in 4 cases and second-line treatment in 4 cases (after failed acetazolamide therapy). The dosage was 1.5-2mg/kg for a mean duration of 1.5 months (6 treatments could be analyzed). This treatment was effective in 5 patients out of 6. One patient had dual therapy. No surgical procedure was necessary in this pediatric cohort. Three patients presented relapses of IIH. The outcome was good with no residual visual impairment in the 13 patients analyzed. One patient was still under medication. COMMENTS: Therapeutic management of IIH in a pediatric population is essentially medical, in some cases limited to lumbar puncture. The first-line treatment is acetazolamide, but this study shows that low doses and short duration are usually chosen. Doses must be increased and treatment prolonged to avoid the use of corticosteroids as a second-line treatment and prevent possible relapses that require close monitoring of visual function. CONCLUSION: The visual prognosis is generally better for this age group compared to adults and no risk factors for visual sequelae were identified. A standardized protocol for management of IIH was proposed.

[The outcome of children presenting with a prenatally diagnosed arachnoid cyst]. / Devenir des enfants présentant un kyste arachnoïdien de diagnostic anténatal.

AIM: Evaluate the outcome of children with prenatally diagnosed arachnoid cysts. MATERIAL AND METHODS: Retrospective study of seventeen cases of children who were diagnosed with an arachnoid cyst during prenatal MRI between July 1994 and January 2007 and followed up for a mean 6 years and 6 months. Follow-up was based on evaluation of clinical files and contacts with the physicians who were following the children. The children were divided into three groups: group 1 normal development, group 2: minor clinical signs, normal schooling, group 3: major clinical symptoms, schooling disturbed. RESULTS: Eight of the 17 patients included in this study underwent derivation surgery for the cyst. Eight of the 17 children were in group 1, and 3 in group 2. Four of the 6 children in group 3 had associated symptoms. Two of the children in group 3 present with a supratentorial cyst, and 4 with a cyst of the posterior fossa. CONCLUSION: The prenatal diagnosis of a arachnoid cyst should be accompanied by a search for associated lesions. The risk of hydroencephalitis should be explained to the parents.

[Optic pathway gliomas in neurofibromatosis type I. Longitudinal study of 30 cases in two multidisciplinary practices]. / Les gliomes des voies optiques dans la neurofibromatose de type 1. Etude longitudinale de 30 cas suivis dans deux consultations multidisciplinaires.

UNLABELLED: The aim of this study was to analyse the outcome of optic pathway gliomas in 30 children with neurofibromatosis type 1, the indications of treatment, and the follow-up and screening protocol. PATIENTS AND METHODS: All patients with a minimal two years follow-up (median six years, range two to 19 years), in two multidisciplinary consultations of Saint-Vincent-de-Paul (Paris) and Purpan (Toulouse) hospitals, were included in the study. In our series, we practiced systematic screening MRI in children under six years' of age or with neuropsychological deficiency that may imply an unreliable ophthalmological examination. RESULTS: Thirty-seven percent (11 patients) had progressive ophthalmological signs and were treated, and 63% (19 patients) were not progressive. Our study confirmed that most of optic pathway gliomas were stable during evolution, but rare cases may have bad prognosis. CONCLUSION: Our study supported the importance of close ophthalmological follow-up during childhood for which screening methods are discussed. There is a consensus to limit treatment for patients with progressive ophthalmological symptoms.

[Neurofibromatosis 1: recommendations for management]. / Neurofibromatose 1: recommandations de prise en charge.

Twenty experts, members of a French medical network devoted to neurofibromatosis 1 have elaborated recommendations for the management of the disease. Bibliography was obtained through a Medline of articles from 1966 to 1999 for the terms neurofibromatosis, NF1, neurofibroma and from textbooks. A consensual document was written taking into account extracted data. An annual careful clinical examination is recommended except in cases with complications. Screening investigations are not recommended due to the rarity of complications, generally symptomatic and easily detected during the clinical follow-up. The only controversial exception might be magnetic resonance imaging for early detection of optic pathway gliomas in young children. A co-ordinated follow-up in specialised multidisciplinary centres, providing patients with a rational management, is recommended.

[Chronic meningococcemia: 3 cases in the immunocompetent child]. / Méningococcémie chronique: trois cas chez l'enfant immunocompétent.

UNLABELLED: Chronic meningococcemia is a part of extra meningeal manifestations of meningococcal disease. Its diagnosis can be difficult because of lack of sensitivity of blood cultures. CASE REPORT: Three cases, concerning immunocompetent children, respectively aged of 14, 10 and 4 years are reported. The clinical course was characterized by recurrent fever, inflammatory joint manifestations and diffuse maculopapules secondary centered by petechiae. Microbiological findings revealed in one case a positive throat culture and presence of meningococcal soluble antigens in blood and urine. In the other two cases, diagnosis was done after done after positive blood culture at the 7th, and 13th days of course. CONCLUSION: The diagnosis should be considered in any children with a prolonged, recurrent fever and cutaneous and joint manifestations even if blood cultures remain negative. The response to therapy by usual antimeningococcal antibiotics is dramatic and curative while a prolonged untreated course may be complicated by metastatic infection.

[Clear cell meningioma: recurrent intraspinal tumor in a child]. / Méningiome à cellules claires: tumeur rachidienne récidivante chez un enfant.

BACKGROUND: Meningiomas represent 1.5% to 4.3% of cerebral and medullar primary tumors in children. CASE REPORT: A 9-year-old girl had a history of thoracolumbar scoliosis. An intracanalar and extramedullar tumor was confined to the lumbar region. Resection identified a clear cell meningioma. A symptomatic and tumoral recurrence occurred 5 months later in the same region. After a second resection, the patient received radiotherapy. At 8 months follow-up, no recurrence was documented. CONCLUSIONS: A stiff and painful scoliosis can be predictive of expansive intracanalar tumor. The recurrent or multifocal evolution of clear cell meningioma show the "aggressive behavior" of this histological type. A preventive radiotherapy could be proposed, depending on the age of the patient and the localization of the tumor.

[Acute orbital myositis and idiopathic inflammatory pseudotumor in children: three cases]. / Myosite orbitaire aiguë et pseudotumeur inflammatoire idiopathique de l'enfant: trois cas.

UNLABELLED: Orbital pseudo-tumors account for approximately 8% of the orbital tumors. They are scarcely described in children and raise diagnostic dilemas, especially when they present as an isolated extra-ocular muscle swelling called idiopathic orbital myositis (IOM). CASE REPORTS: A diagnosis of inflammatory orbital pseudotumors (IOPT) was made in three children aged 7, 13 and 14 years from clinical and CT scan and/or MRI findings associated with histological data in two of them. Two of these IOPT presented as IOM. Analysis was made in a effort to eliminate intra-orbital tumors, especially rhabdomyosarcoma. CONCLUSION: The abrupt onset of the orbital signs, often related in the literature, was not a specific diagnostic criterion regarding to embryonic rhabdomyosarcoma. The inconstant presence of inflammatory signs and the absence of local osseous defect could be more discriminating. Although diagnostic procedure, including histological documentation, was difficult, even dangerous, surgical biopsy should be recommended. Eventually, considering the mandatory multidisciplinary care, steroid therapy response should be evaluated as a diagnostic test.

[Pseudotumor forms of neurosarcoidosis in children. Diagnostic difficulties and therapeutic management]. / Formes pseudo-tumorales de la neurosarcoïdose chez l'enfant. Difficultés diagnostiques et prise en charge thérapeutique.

In systemic sarcoidosis, neurologic manifestations are possible and occurred in 5 p. 100 of cases. The diagnosis is easier when sarcoiddosis is known, but in half case neurologic symptoms are inaugural. In these cases, involvement of other sites (liver, lung, eyes or skin) by the disease is needed to confirm sarcoidosis. Main manifestations in neurosarcoidosis are cranial nerve palsy, diabetes insipidus or chronic aseptic meningitis, but sometimes sarcoidosis can present as an intracranial mass. The diagnosis of neurosarcoidosis may be difficult and could be confused with infection (such tuberculosis or mycosis), with inflammatory diseases (such multiple sclerosis) or with neoplasm, particularly in case of oedema. Brain biopsy may be necessary in isolated neurosarcoidosis if no peripheral histology evidence of noncaseating granulomas has been obtained. Treatment with steroids alone is the best choice for initial therapy but must be prolonged. It is difficult to predict accurately the response to steroids and relapse may be possible after a long time. Other immunosuppressive therapeutics or radiotherapy have been used in patient with refractory neurosarcoidosis. Sequential magnetic resonance imaging is the useful mean for the follow-up of neurosarcoidosis.

[Association of venous angioma and cavernoma of the posterior fossa]. / Association d'un angiome veineux et d'un cavernome au niveau de la fosse postérieure.

BACKGROUND: Association of venous angioma to cavernous malformation is rare. If bleeding occurs, it must be assigned to the cavernous malformation. CASE REPORT: A 4 year-old boy suffered from an acute ataxia. Investigation showed a venous angioma and a cavernoma malformation in the posterior fossa. The patient was admitted again at the age of 8 years for a new episode of acute ataxia due to cerebellar hematoma. A conservative treatment was settled because of the risk of venous infarction. CONCLUSION: Venous angiomas are rarely symptomatic and are considered as normal venous variants. Indeed, the cavernomas are true malformations with a high bleeding potential. When both lesions are associated and bleeding occurs, only the cavernous malformation has to be removed if surgically accessible.