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.

Desmoplastic infantile astrocytoma with benign histological phenotype and multiple intracranial localizations at presentation.

Desmoplastic infantile astrocytoma (DIA) and desmoplastic infantile ganglioglioma (DIG) are rare intracranial tumors that mostly occur in the first 2 years of life and involve superficial cerebral cortex. Despite the large size of these lesions and some worrisome histological and radiological features, prognosis is generally favorable after gross total resection. We report an original observation of a desmoplastic infantile astrocytoma in a 5-year-old boy with multiple localizations on initial presentation, including the unusual subtentorial region. Magnetic resonance imaging showed a temporal tumor with prepontine and interpeduncular extension, and two other distinct localizations in cisterna magna and left cerebellar hemisphere. Leptomeningeal enhancements were present around the basal cistern. The surgical samples, corresponding exclusively to subtentorial lesions, were devoid of anaplastic features; the temporal lesion was untouched because of the interpeduncular extension. Adjuvant chemotherapy was applied, with shrinkage of lesions. DIA and DIG are more generally unifocal at initial presentation. When the tumor is large, multilobular involvement is common, but multiple location of DIG is, on the contrary, very rare. Previously, only five cases of DIG/DIA located in two or more separate locations have been published. We report the sixth, and first noninfantile, case of DIA/DIG with multifocal initial presentation.

[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.

[Orbital tumors in children: CT and MR imaging features]. / Tumeurs orbitaires chez l'enfant: revue iconographique en TDM et IRM.

The purpose of the article is to review the CT and MR imaging features of orbital tumors in children. Tumors in children are usually different than those in adults. Clinical symptoms are usually non-specific. Clinical examination combined with US may be sufficient for diagnosis and follow-up of benign and superficial lesions. CT and/or MRI are needed for deep or malignant lesions. CT is valuable for osseous and/or calcified lesions. MR is advantageous because of its superior spatial resolution and non-ionizing nature. Malignant tumors correspond to about 20% of lesions and include primary tumors (retinoblastoma, rhabdomyosarcoma) and metastases. Benign pathology is more frequent (80%) with dermoid cyst corresponding to about 50% of orbital masses.

[Fragile X syndrome and white matter abnormalities: Case study of two brothers]. / Syndrome de l'X fragile et anomalies de la substance blanche : à propos d'une fratrie.

Fragile X syndrome is the most usual cause of hereditary intellectual deficiency. Typical symptoms combine intellectual deficiency, social anxiety, intense emotional vigilance, and a characteristic facial dysmorphy. This is subsequent to a complete mutation of the FMR1 gene, considering a semidominant transmission linked to the unstable X. The expansion of the CGG triplet greater than 200 units combined with a high methylation pattern lead to a transcriptional silence of the FMR1 gene, and the protein product, the FMRP, is not synthesized. This protein is involved in synaptic plasticity. Brain MRI can show an increased volume of the caudate nucleus and hippocampus, combined with hypoplasia of the cerebellar vermis. Fragile X Associated Tremor Ataxia Syndrome (FXTAS) syndrome is a neurodegenerative disorder occurring in carriers of the premutation in FMR1. Brain MRI shows an increased T2 signal in the middle cerebellar peduncles. This syndrome is linked to a premutation in the FMR1 gene. We report here the case of two brothers presenting a typical fragile X symptomatology. Brain MRI showed hyperintensities of the middle cerebellar peduncles. Such MRI findings support the assumption of a genetic mosaicism.

[Reversible cerebral vasoconstriction syndrome: A rare pediatric cause of thunderclap headaches]. / Syndrome de vasoconstriction cérébrale réversible : une cause de céphalée en coup de tonnerre peu connue chez l'enfant.

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by thunderclap headaches with diffuse segmental constriction of cerebral arteries that resolves spontaneously within 3 months. We report on a case of a 13-year-old boy presenting with acute severe headaches, triggered by physical exertion. His past medical history was uneventful. Moderate headache persisted between exacerbations for 4 weeks. He secondarily presented with signs of intracranial hypertension. Brain magnetic resonance angiography (MRA) revealed multifocal narrowing of the cerebral arteries. A glucocorticoid treatment was started based on the hypothesis of primary angiitis of the CNS. The symptoms rapidly improved, and repeat angiography at 3 months showed no vasoconstriction. Although pediatric cases are rare, RCVS should be considered in a child complaining of severe headache, especially after the use of vasoactive drugs or after Valsalva manoeuvres. RCVS is attributed to a transient, reversible dysregulation of cerebral vascular tone, which leads to multifocal arterial constriction and dilation. Physical examination, laboratory values, and initial cranial computed tomography are unremarkable, except when RCVS is associated with complications. Thunderclap headaches tend to resolve and then recur over a 1- to 4-week period, often with a milder baseline headache persisting between acute exacerbations. Angiography shows segmental narrowing and dilatation of one or more arteries, like a string of beads. Despite the absence of a proven treatment, important steps should be taken during the acute phase: removal of precipitants such as vasoactive substances, giving the patient rest, lowering blood pressure, and controlling seizures. Drugs targeted at vasospasms, such as calcium channel inhibitors, can be considered when cerebral vasoconstriction has been assessed. In most patients, the RCVS symptoms resolve spontaneously within days or weeks. Ischemic and hemorrhagic stroke are the major complications of the syndrome. A diagnosis of RCVS can only be confirmed when the reversibility of the vasoconstriction is assessed.

In vivo geometrical evaluation of Cheneau-Toulouse-Munster brace effect on scoliotic spine using MRI method.

OBJECTIVES: The aim was to quantify the immediate effect of the Cheneau-Toulouse-Munster brace (worn at night) on scoliotic curvatures in vivo.Design. A three-dimensional geometrical model of the spine was developed using magnetic resonance images. BACKGROUND: Many corrective ortheses were proposed for the orthopaedic treatment of idiopathic scoliosis. Simple radiographs were not sufficient to analyse the three-dimensional spinal deformations. So, three-dimensional geometrical models were developed using stereoradiography and axial tomography. MRI has been only used clinically for investigation of intervertebral disc disorders. METHOD: MRI examination had been performed on 14 girls having an idiopathic scoliosis and wearing a first Cheneau-Toulouse-Munster brace. The protocol investigated was performed with and without brace. Using an in-house image processing software and the pre-post processing software Patran, two geometrical models of the spine (spine without brace and spine with brace correction) were obtained, respectively, for each patient, the models including the vertebral bodies. RESULTS: Our method reproducibility was found to be 0.5 mm on the displacements and 2.5 degrees on the rotations. The Cheneau-Toulouse-Munster brace decreased the coronal shift forward, the coronal tilt, the axial rotation, and increased the sagittal shift forward and the sagittal vertebral tilt. DISCUSSION: The results showed that the Cheneau-Toulouse-Munster brace had a three-dimensional and personalised action on vertebrae. This technique using MRI provides no irradiation and allows the soft tissue visualisation, but actually is not dedicated for clinical use and is limited to the lying position. RELEVANCE: The qualitative and quantitative data obtained allowed a better description of the Cheneau-Toulouse-Munster brace effect on scoliotic spine, and will help the orthopaedist in the brace design and the clinician in the scoliosis comprehension.

Sensorineural hearing loss and otosclerosis: a clinical and radiologic survey of 437 cases.

The aim of this study was to determine if a relationship exists between bone level thresholds and the extension of otosclerotic foci within the otic capsule. The study consisted of a retrospective case review in a university hospital. We included patients who underwent surgery for otosclerosis in our department and who had a CT scan prior to surgery. We analyzed the data charts and CT scans of 437 cases (386 patients). On CT scan, we distinguished patients with fenestral otosclerosis and/or with a pericochlear focus. A pericochlear focus could be extended (Group 2) or not (Group 1) to the cochlear endosteum. Data for Groups 1 and 2 were compared with those for the control group of all patients for whom CT scan showed no cochlear focus (Group 3). Of the 437 CT scans, 399 were positive (91.3%). An anterior focus was reported in 305 cases (69.8%), a footplate thickening in 21 cases (4.8%) and both anomalies were encountered in 60 cases (13.7%). A pericochlear focus was reported in 53 examinations. This focus was extended to the endosteum in 14 cases (26.4% of the pericochlear foci). In Group 1, preoperative air conduction (AC) thresholds were significantly lower than in the control group (p < 0.05). The air--bone gap was also significantly larger in Group 1 (p < 0.05). Bone conduction (BC) thresholds were lower in Group 1 than in the control group but the difference was not significant. In Group 2, preoperative AC thresholds were significantly lower than in the control group (p < 0.05). BC thresholds were also lower in Group 2 than in the control group and the difference was significant (p < 0.05). As a result of this study, we assume that there may be a relationship between bone level thresholds and the radiological extension of otosclerosis within the otic capsule.

[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.

Doppler ultrasound study of the anterior cerebral artery in neonates.

In neonates doppler ultrasound of the anterior cerebral artery (ACA) enables cerebral haemodynamics to be studied in a non-invasive manner at the patient's bedside. The signal of the pericallosal artery is recorded through the fontanelle with a 7.5 mHz real-time probe. Two parameters are monitored: Pourcelot's resistance index and mean velocity which reflects blood flow rate. Having established normal values according to the gestational and post-natal ages, the authors describe the changes in cerebral circulation observed in such pathological situations as intraventricular haemorrhage, apnoea, patent ductus arteriosus, hydrocephalus and post-asphyxia syndrome.

[Dissection of the intracranial arteries. Apropos of 10 cases]. / Dissections des artères intracrâniennes. A propos de 10 observations.

Ten cases of spontaneous dissection of the cerebral arteries are reported. 3 males and 7 females aged 6 to 60 years (mean age 30 years) were investigated in the Department of Neuroradiology of Toulouse between 1989 and 1994 with CT, angiography and MRI. In 5 cases the dissection involved the carotid artery, in 5 cases the vertebro-basilar system. The clinical presentation was of two types: ischaemic stroke (7 cases) or subarachnoid haemorrhage (3 cases). Their evolution is never lethal, contrary to the classical descriptions of the literature. In all cases an initial angiography then follow up has been performed showing an irregular located arterial stenosis. The diagnosis of intracranial dissection is sometimes made in front of a dissequant aneurysm. In case of doubt, magnetic resonance (MR) imaging is helpful showing a linear hypersignal parallel to an arterial segmental stenosis, and angiography MR an irregular aspect and stenosis of the endoluminal artery.

[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.

[Septic arthritis of a lumbar facet joint associated with epidural and paravertebral soft tissue abscess]. / Arthrite septique interapophysaire postérieure lombaire avec abcès épidural et des parties molles paravertébrales.

Septic arthritis of the lumbar facet joint is rare, probably underdiagnosed, often associated with complications such as epidural abscess and paraspinal muscles abscess. Diagnosis is based on imaging evaluation. Plain radiographs of the lumbar spine are not helpful because often nomal. Bone scintigraphy is very sensitive but non-specific. CT scan can confirm the diagnosis and guide the needle biopsy. MRI is the preferred imaging modality for diagnosis. MRI shows early bone and joint involvement and it is helpful in detecting epidural and paravertebral soft tissue lesions.

[Spontaneous resolution of syringomyelia in a child with Chiari I malformation: a case report]. / Résolution spontanée d'une cavité syringomyélique dans le cadre d'une malformation de Chiari I chez un enfant: à propos d'un cas.

Cervicothoracic syringomyelia is a frequent feature in Chiari I malformation. It can be symptomatic or not, and is well demonstrated by magnetic resonance imaging (MRI). Its spontaneous resolution is uncommon. The authors report a case of spontaneous resolution of a thoracic syrinx in an 18-year-old patient with a Chiari I malformation. MRI study performed 6 years previously because of worsening headaches demonstrated a Chiari I malformation associated with a syrinx cavity. The cavity disappearance was noted after improvement of the symptoms.

[Multiple cerebral telangiectasias. Apropos of an anatoma-radioclinical case]. / Télangiectasies cérébrales multiples. A propos d'un cas anatomo-radio-clinique.

UNLABELLED: Telangiectasias are vascular malformations corresponding to dilated capillary separated by nervous parenchyma. They are generally asymptomatic and discovered during autopsy. CASE REPORT: We describe the case of a 2-year-old girl who was admitted for drowsiness and vomitings with craniomegaly and right hemiparesis. The cerebral imaging demonstrated large amounts of calcium in the region of pons and left thalamus with a contrast enhancement throughout these calcifications. The thalamic lesion was cystic with obstruction of the third ventricle and hydrocephalus. There were multiple calcifications scattered throughout the basal ganglia and the white matter. The latter had a low density on CT and high signal intensity on MRI (T2). The cerebral angiographic study showed a blush in the pons and the thalamus. Clinical course was fluctuating or intermittently progressive. Finally, in spite of radiotherapy and oral corticosteroid treatment, the child became quadriparesic with oculomotor palsy. She suddenly died at age 4 years and 6 months from a hemorrhage of the pons. Neuropathological study showed two clusters of telangiectasias with calcifications in the pons and the thalamus. Other calcified vascular malformations were seen in the white matter and the basal ganglia. Near the lesions, astrocytar gliosis and edema were observed. The white matter was malacic with isolated calcifications. CONCLUSION: Cerebral telangiectasias may be multiple and may produce severe neurologic disorders, occurring in infancy with fluctuating clinical course. Arteriography may show these usually cryptic vascular malformations. This diagnostic should be kept in mind in view to the neuroradiological aspect we report here.

[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.

[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.

[Superficial siderosis of the central nervous system: a case report]. / Sidérose superficielle du système nerveux central: à propos d'un cas.

Superficial siderosis of the central nervous system is secondary to chronic subarachnoid bleeding. However, the underlying etiology is not always detected. Superficial siderosis can be diagnosed at MRI by the presence of a hypointense rim along the brain surface on gradient echo T2W images. The authors report a case of superficial cerebral siderosis where the underlying etiology remained undiagnosed in spite of extensive neuroradiological work up.