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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 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.

It is already established that a nitrogen content in carbon fibres induces poor high tensile strength properties of the fibres. Up to now the nitrogen localization in the fibre, particularly along the diameter, was not known, due to the small size of the fibres (7 μm) and the insufficient sensitivity of the usual analytical techniques, using X-rays or ion beam for instance, for such low atomic number elements (nitrogen and carbon). By using electron Energy Loss Spectroscopy (EELS) in a Philips EM 400T microscope equipped with a V.G. electron spectrometer, we have determined this distribution for the Toray 300 carbon fibre. The measurements have been made by using the carbon and nitrogen K edge intensity when EEL spectra correspond to thin enough samples, thickness ≤ 500 A. The accuracy of this determination is on the order of 10%. In this way, we have measured a NC atomic concentration varying from 2 to 7%. For all the Toray 300 fibres a similar variation of the ratio is observed. The nitrogen content is low in the core of the fibre, about 2%. It remains practically constant in the whole center of the fibre and grows rapidly to 6–7% in the periphery. These measurements reveal a skin core concentration gradient effect in the high tensile strength fibres. They confirm that it is necessary to avoid this structure if one desires ultra-high mechanical properties for the fibres.

A 16-day-old female newborn was admitted to the emergency department after cardiopulmonary arrest. Total-body radiographs and non-enhanced CT of the brain showed fracture of the right clavicle, pericerebral hemorrhage and brain damage with reversal sign. The infant died on the day of her hospital admission. Because child abuse was suspected, a medicolegal autopsy was ordered by the legal authorities. Prior to autopsy, total-body MRI and CT were performed. Results of the ante- and postmortem investigations were compared with each other and then with the autopsy findings. Postmortem brain imaging showed persistence of the reversal sign. To the best of our knowledge, this is the first case describing hypoxic ischemic damage of the brain parenchyma on antemortem CT and persisting on postmortem imaging in a child abuse case.

MRI has been clinically only used for investigation of intervertebral disc disorders. In this study, MR images were used and a new 3D modelling of the intervertebral discs was proposed. MRI examination had been performed on fourteen girls presenting an idiopathic scoliosis and wearing a first CTM brace. Using an in-house image processing software and the pre-post processing software Patran, geometrical models were obtained with and without brace for each patient. These models included the outline of the intervertebral high intensity zone, composed of the nucleus and a part of the annulus. The shift forward between disc high intensity zone centres and body centres was found to be varying from 0 to 8mm. The sagittal and coronal shifts forward appeared in the curvature convexity and were maximum at the curvature apex. The intervertebral disc wedging was found to be varying from -10 degrees to +10 degrees. On these fourteen analysed patients, the CTM brace decreased the coronal shift forward between disc high intensity zone centres and body centres, and increased the sagittal intervertebral wedging. The intervertebral disc informations obtained represented new data in the scoliotic deformation description. But this method was not adapted for a clinical use. The qualitative and quantitative data obtained will help the orthopaedist in the brace design and also the clinician in the scoliosis comprehension.

The aim of the study was to implement a methodology to quantify in vivo and from magnetic resonance imaging (MRI) the 3D geometrical properties of intervertebral discs (IVDs) in early idiopathic scoliosis with small curves. MRI data were posttreated using a custom-made image processing software to semiautomatically determine the location of disc centres, the location of the nucleus pulposus (NP) and the ratio between the NP volume and the disc volume. MRI was performed in a clinical protocol involving 14 patients having an early idiopathic scoliosis. First, the 3D reconstruction errors were quantified using a reproducibility test (intraoperator and interoperator) in one IVD (L5-S1). The maximal errors in location were 0.79 mm in the frontal plane, 1.84 mm in the sagittal plane and 0.76 mm in the vertical plane. The maximal error in relative volume was 42%. Second, the nucleus migration and relative volume were quantified in discs T5-T6 to L5-S1. No significant relative volume variation was detected. Concerning the disc migration, no significant differences were found in the sagittal and axial planes. In the frontal plane, significant differences were observed at the apex of the scoliotic curvature when the Cobb angle was > or =20 degrees . This innovative study in early scoliosis showed reproducible preliminary results, and its application to improve diagnosis and follow-up will be established in an enlarged patient database.

This paper deals with the problem of modeling influence on the control algorithm. Long range adaptive predictive control algorithms are described, based on three different system descriptions: a linear model, a cascade of nonlinear and linear part, and a nonlinear model. These control laws have been applied to a continuous fermentation plant, and their performance are compared. >

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.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.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.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.

Objectifs L’hemangioendotheliome kaposiforme est une tumeur vasculaire rare qui peut se compliquer d’un syndrome de Kasabach Merritt (SKM). Ce syndrome induit une thrombopenie majeure a une coagulopathie intra vasculaire disseminee pouvant mettre en jeu la vie du patient. De nombreuses alternatives therapeutiques medico-chirurgicales sont proposees dans la litterature mais leur efficacite et leur toxicite ne permettent pas de definir un consensus clair de prise en charge. Materiel et methodes : Nous decrivons le cas d’un enfant de 2 ans presentant un hemangioendotheliome kaposiforme cervico-occipital avec un SKM en echec therapeutique medicamenteux et sans recours chirurgical envisageable. Resultats Une adaptation de la compression mecanique decrite en 1984 par Stringel, par realisation d’un casque compressif sur mesure a ete initiee avec des resultats cliniques et biologiques tres satisfaisant des 2 mois de traitement. Aves un an de recul, aucune recurrence du SKM n’est survenue sans aucun traitement adjuvant. Conclusions A la lumiere de cette observation, nous pensons que les possibilites de compression doivent etre systematiquement etudiees dans la prise en charge du SKM chez l’enfant quelle que soit sa localisation.

Piezoelectric aluminum nitride (AlN) thin films have been developed to realize ultrasonic transducers. AlN up to 1.5m is deposited at low temperature (140 degree(s)C) by reactive DC magnetron sputtering of an Al target in argon and nitrogen on Si, Si/SiO2/Al, and Si/Al substrates, and is wet etched (rates from 0.1 micrometers /min to 0.2 micrometers /min and selectivity of 1:10 with Al, and no etching with Si). SiO2/Al/AlN/Al, Al/AlN/Al and Si/AlN/Al square and circular membranes, from 10 micrometers to 1.5 mm size are fabricated using silicon deep reactive ion etching (DRIE), which gives etch profiles about 90, which allows larger integration density than wet anisotropic etching for ultrasonic transducers arrays. By varying size and thickness of membranes, resonance frequencies from 10 kHz to 20 MHz are expected, acoustic and electrical measurements are in progress. Ultrasonic transducers using this technology will be used to measure flows velocity by Doppler method. Other potential applications for ultrasonic transducers include medical ultrasounds and sonar. Other structures are also in progress such as Thin Film Bulk Acoustic Resonator (TFBAR), and Lamb wave devices using this technology.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

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 (p0.05). The air--bone gap was also significantly larger in Group 1 (p0.05). 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 (p0.05). BC thresholds were also lower in Group 2 than in the control group and the difference was significant (p0.05). 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.

To investigate a narrow internal auditory canal (IAC) syndrome using functional magnetic resonance imaging (fMRI) of the auditory cortex.The study design was a case report. The follow-up period lasted 18 months.The study was carried out in the audiology clinic of an ear, nose, and throat department and in the department of pediatric neuroradiology at a university hospital.Age-appropriate observational audiometry, objective audiovestibular tests, computed tomography (CT), magnetic resonance imaging (MRI), and (fMRI) of the auditory cortex were performed to analyze in detail the profound deafness of a young child.Audiovestibular examination demonstrated both measurable hearing and normal vestibulo-ocular reflex, and CT showed narrow IACs combined with normal labyrinths. Axial MR images completed by sagittal sections perpendicular to the IAC delineated a single nerve that was initially supposed to be the facial nerve. No cochleovestibular nerve was identified. However, fMRI performed with the patient under general anesthesia demonstrated activation of the primary auditory cortex during 1-kHz monaural stimulation on the left side.The absence of cochleovestibular nerve on MR studies cannot exclude connections between the inner ear and the central auditory pathways. This might be caused by a lack of spatial resolution of anatomical MR studies. The single nerve delineated within the IAC might also carry both facial and cochleovestibular fibers. Functional MRI can assess the cortical response to acoustic stimuli when aplasia of the cochleovestibular nerve is suspected. This case study illustrates a novel and atypical presentation of cochlear nerve dysplasia.

Polycrystalline Aluminum Nitride (AIN) films were deposited on Si(100), A1/Si(100), and A1/SiO,/Si substrates by reactiveDirect Current (DC) magnetron sputtering of an Al target, under different conditions of substrate temperature, pressure, N7 I N7 + Ar ratio. The film properties were investigated by X-Ray Diffraction (XRD), scanning electron microscopy (SEM)and atomic force microscopy (AFM). Deposition rates in the range of 1 .2 to 1 .8 trn/h were obtained, the film grain sizewas around 4Onrn. To fabricate test structures, wet chemical etching was developed to etch A1N with a good selectivityrespect to Al and Si.Visual aspect and surface roughness show that the maximum temperature must be less than 300°C. X-Ray Diffractiontogether with dielectric constant measurement show that films are better oriented on Si(lOO) than on Al/Si(100).First results give relative dielectric constant S1 (T: free displacement) = 9.5 to I 1 , Eb, = 200 to 5OOV/trn, piezoelectriceffect, good crystal orientation.Membranes were also fabricated using deep reactive ion etching plasma (DRIE), to characterize the film and to fabricateMEMS sensors and actuators, and acoustic wave devices.Keywords: A1N, piezoelectric thin film, reactive DC sputtering, MEMS, acoustic wave devices

Pure sensorineural hearing loss is not a rare finding in otological practice. Numerous aetiologies could be at the origin of such a deficit. However, otosclerosis is very rarely cited as a cause of pure sensorineural hearing loss. We present one such case of pure sensorineural hearing loss linked to otosclerosis in a 30-year old caucasian male and underline the high contribution of computed tomography to confirm such a diagnosis. Pure sensorineural hearing loss due to otosclerosis is a rare event and can be misdiagnosed. The clinical diagnosis of such a disease may be difficult. In these cases, CT-Scan is the exam of choice to confirm the diagnosis.

Pituitary stalk transection is a non-negligible cause of growth hormone (GH) deficiency.We studied 22 children (13 boys, nine girls) aged at the first clinical manifestations from 2 days to 10 years (average = 5.33 +/- 2 years). Pituitary stalk transection was assessed by the means of magnetic resonance imaging (MRI). The children's past history showed fetal distress in 12 cases (54.5%), cranial trauma in three (13%) and a midline anomaly in three (13%). The first clinical manifestations were neonatal hypoglycemia (two cases), decreased growth velocity (18 cases) and diabetes insipidus (two cases).GH deficiency was complete, present from the onset in 19 of 22 cases and isolated in four. Fifteen of 22 cases had adreno-corticotrophic hormone (ACTH) and thyroid stimulating hormone (TSH) deficiency. Diabetes insipidus was present in six cases and revealed the syndrome in two. All children older than normal age of puberty (n = 10) had gonadotropin deficiency. In our study, these hormonal anomalies progressed from isolated GH deficiency to multiple hormonal deficiencies.The recently described stalk transection syndrome is relatively frequent and should be suspected after cranial trauma or fetal distress syndrome. The outcome is progressive evolution towards panhypopituitarism and these patients require regular clinical survey and hormonal controls.

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).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.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.

Spinal cord abscesses are extremely rare, even in intravenous drug abusers. They usually have a poor prognosis unless diagnosed and treated promptly. MRI is the best imaging modality for diagnosis and follow-up. We report a 42-year-old man, an active intravenous drug user, HIV negative, who developped subacute tetraplegia from an intramedullary abscess caused by Staphylococcus aureus. Immediate decompressive surgery and antibiotic treatment led to progressive recovery.

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 to cavernous malformation is rare. If bleeding occurs, it must be assigned to the cavernous malformation.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.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.

Telangiectasias are vascular malformations corresponding to dilated capillary separated by nervous parenchyma. They are generally asymptomatic and discovered during autopsy.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.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.

International audience; The physicochemical properties of SiC-based deposits, obtained from the thermal decomposition of CH3SiCl3(MTS) in hydrogen, under conditions of reduced pressure (P < 20 kPa) and low temperature (T < 1400 K), are studied. The morphology, the structure, the nainostructure and the chemical composition of the deposits are discussed from a kinetic and a thermodynamic point of view. They are closely related to the kinetic control regime (either mass transfer or chemical reactions). The silicon excess has a pronounced influence on the morphology and the nanostructure of the deposits.

International audience; The inhibitory role of HCl and oxygen in the chemical vapour deposition of SiC-based ceramics from the SiCHCl system, is pointed out in terms of nucleation and growth process on the basis of experimental and theoretical approaches. The addition of HCl to methyltrichlorosilane MTS-H2 gaseous precursors (i) decreases the nucleation and growth rate, (ii) induces a transition from a diffusion to a reaction rate control of the deposition process, (iii) improves the smoothness of the films surface, (iv) results in a transition from anisotropic films with columnar microstructure and Si, C and O concentration gradients to nanocrystallized materials with quite constant Si, C and O contents. These behaviours are tentatively explained by assessments of the gas phase super saturation and calculations of the chemisorbed layer composition. The occurrence of oxygen within the nanocrystallized films is then related to the growth inhibition effect and the presence of silicon excess shown by EELS analyses.

Several (Al,Si,N) compounds have been obtained by LPCVD in a vertical hot-wall reactor using aluminium trichloride, silicon tetrachloride and ammonia as source gases, with nitrogen as the carrier gas. In order to determine both their structure and local chemical composition, several deposits have been examined by analytical transmission electron mimscopy combining electron diffraction (ED), high resolution electron microscopy (HREM) and electron energy loss spectroscopy (EELS). It has been confirmed that the chemical composition of the materials as well as the size of the "nanocrystals" observed in the deposits are strongly dependent on the temperature and the reactive gas flow. It has also been shown that for the range of temperature (1273 K-1373 K) used in this work these "nanocrystals" have the wurtzite structure of aluminium nitride.

Immunoreactivity, cytochemical, immunocytochemical characteristics and subcellular distribution of neutrophil alkaline phosphatase (NAP) were investigated in blood and/or smear samples from 18 women aged 23-46 years (mean 32.5 years) with trisomy 21 fetuses (17-21 weeks) and 28 women aged 20-42 years (mean 31 years) with normal fetuses (17-22 weeks). Immunochemical NAP investigations were carried out in 8 pathological and 8 normal pregnancies; cytochemical and immunocytochemical procedures were carried out in 18 pregnant women with trisomy 21 fetuses and 28 controls. NAP from women with trisomy 21 fetuses is characterized by: (1) a significant decrease in reactivity with anti-liver-type alkaline phosphatase (AP) and anti-NAP antisera; (2) low or very slight reactivity with antiplacental or anti-intestinal antibodies; (3) marked dispersion of NAP lead citrate reaction products or anti-NAP antibody colloidal gold-labelling in neutrophil cytoplasms, as detected by electron microscopy. This subcellular AP distribution (extramembranous) is different from that of normal NAP sites associated with plasma membrane, nuclear membrane and secretory vesicles. The NAP immunochemical and cytochemical characteristics suggest that neutrophils of a woman with a trisomy 21 fetus contain two AP isoenzymes: the liver/bone type and an atypical AP.

International audience; Disk-shaped Y2O3 nanoprecipitates were observed to appear systematically in Ba-deficient YBa2Cu3O7 (YBCO) films obtained by thermal MOCVD. These disks have an average size of 30nm in diameter and 4nm thick, and face parallel to the (001) YBCO planes. The observation by HREM reveals the epitaxial growth of the Y2O3 inclusions without affecting the stacking sequence of the surrounding YBCO matrix.

International audience; Y2O3 inclusions locally embedded in MOCVD YBCO films have been unambiguously identified by HREM and associated image calculations. The nanoprecipitates exhibit rectangular shapes, with their largest interfacial facets lying parallel to the (001) plane. The interfaces features can be interpreted at an atomic scale on the basis of lattice-matching arguments.

The prognosis for congenital brain tumors is usually poor, so that their management during pregnancy is difficult.Case 1. A large cystic mass was revealed by ultrasound at the 37th week of pregnancy; it was located near the brain stem and was associated with ventricular dilation. The newborn was delivered by cesarean section because of an abnormally enlarged head. The CT scan confirmed the presence of this mass containing a fluid that was found to be normal after needle aspiration. Surgical shunting of excess fluid was ineffective, and progressive deterioration prevented further exploration and/or treatment. The child is still living, confined to his bed, at the age of 5 years. Case 2. Ultrasonography at the 30th week of pregnancy showed a tumor located near the brain stem with dilation of the entire ventricular system. Post mortem examination after abortion revealed a capillary and cavernous hemangioma. Case 3. Ultrasonography at the 34th week of pregnancy showed dilation of the ventricular system. As a result, birth was induced. CT scan and MRI of the newborn showed a mixed, solid and liquid, mass in the posterior fossa. Post mortem examination showed a papilloma of the choroid plexus.These rare congenital tumors are usually revealed by ultrasonography showing ventricular dilation. Advances in imaging techniques, especially MRI of fetal brain, should help in the management of such tumors.