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Les méningo-encéphalocèles (MEC) sincipitaux sont des malformations congénitales rares qui se manifestent par une hernie de tissu cérébral ou méningé à travers une ouverture dans l'étage antérieur de la base du crâne. Ces malformations touchent toujours l'os frontal, plus précisément la région glabellaire et l'angle naso-frontal. Une collaboration entre Médecins du Monde et le Children's Surgical Center de Phnom Penh a permis de prendre en charge plus de quatre cents cas sur vingt ans. Les patients n'ont généralement pas eu d'examens radiologiques, les stratégies chirurgicales étant basées sur les observations cliniques et peropératoires. Il existe plusieurs formes cliniques de MEC : naso-frontales, naso-ethmoïdales, et naso-orbitaires. La classification de Suwanwela de 1972 reste la plus pertinente. Les MEC naso-frontales sont souvent associés à une importante expansion cutanée sans déformation osseuse majeure, contrairement aux MEC naso-ethmoïdales, qui entraînent des déformations significatives et sont les plus fréquentes. Les MEC naso-orbitaires, plus rares, provoquent le plus souvent une augmentation du volume orbitaire. La nature du tissu hernié et le volume de la hernie sont déterminants pour la stratégie chirurgicale. La canthopexie, un élément clé de la reconstruction, doit être précise et répond à des règles strictes pour assurer un résultat esthétique. Le remodelage fronto-nasal finalise la réparation. La chirurgie des MEC suit des principes bien codifiés. Le contexte humanitaire influence la prise en charge, avec un accent sur la sécurité chirurgicale et la transmission des compétences. Le traitement repose sur une vision clinique plus que radiologique, même si les avancées en imagerie sont aujourd'hui disponibles au Cambodge. Le suivi à long terme, surtout chez les enfants, reste un défi à documenter pour évaluer les impacts sur la croissance et la stabilité des résultats chirurgicaux. Sincipital meningoencephaloceles (MECs) are rare congenital malformations characterized by the herniation of brain or meningeal tissue through an opening in the anterior floor of the skull base. These malformations always affect the frontal bone, specifically the glabellar region and the naso-frontal angle. A collaboration between Médecins du Monde and the Children's Surgical Center in Phnom Penh has enabled the treatment of over four hundred cases over twenty years. Patients typically have not undergone radiological examinations, with surgical strategies based on clinical and intraoperative observations. There are several clinical forms of MECs: naso-frontal, naso-ethmoidal, and naso-orbital. The 1972 classification by Suwanwela remains the most relevant. Naso-frontal MECs are often associated with significant skin expansion without major bone deformity, unlike naso-ethmoidal MECs, which lead to significant deformities and are the most common. Naso-orbital MECs, being rarer, most frequently result in an increased orbital volume. The nature of the herniated tissue and the volume of the hernia are critical in determining the surgical strategy. Canthopexy, a key element of reconstruction, must be precise and adhere to strict rules to ensure an aesthetic result. The fronto-nasal remodeling completes the repair. The surgery for MECs follows well-codified principles. The humanitarian context influences management, with an emphasis on surgical safety and skill transmission. Treatment relies more on clinical assessment than radiological, although imaging advancements are now available in Cambodia. Long-term follow-up, especially in children, remains a challenge to document in order to evaluate the impacts on growth and the stability of surgical outcomes. [ABSTRACT FROM AUTHOR]

Objectif: Nous rapportons la prise en charge anté et post natale d’un enfant porteur d’une fente médiane faciale associée à une méningo-encéphalocèle fronto-èthmoidale. Matériel et méthode: Au cours de l’échographie fœtale à 35 SA chez une femme de 29 ans caucasienne primigeste, une tumeur faciale est découverte chez le fœtus de sexe masculin. Une IRM fœtale à 37 SA est réalisée afin de préciser cette anomalie. Cet examen met en évidence une lésion naso-labiale médiane de tonalité liquidienne, développée au dépend du maxillaire supérieur. Aucune anomalie cérébrale n’est décelée. L’accouchement est déclenché à 39 SA. A l’examen physique post-natal, l’enfant présente une tumeur pédiculée implantée sur la ligne médiane du maxillaire supérieur, associé à une fente labiale bilatérale. Le reste de l’examen clinique est sans particularité. Une première intervention chirurgicale ; réalisée à J1 de vie, consiste en l’exérèse de cette tuméfaction ainsi qu’en la fermeture de la fente labiale. L’examen anatomopathologique de la masse diagnostique d’une méningo-encéphalocèle fronto-éthmoidale associée à une fente labiale bilatérale. Une tomodensitométrie ainsi qu’une IRM cérébrale réalisées à J7 et J12 de vie, mettent en évidence une disjonction des structures osseuses et cartilagineuses médianes faciales, avec présence d’une image liquidienne développée entre l’étage antérieur de la base du crâne et le cartilage septal. Les structures cérébrales sont par ailleurs normales. La cure neuro-chirurgicale de la méningo-encéphalocèle est réalisée au 10eme mois de vie de l’enfant par voie bicoronale ; dans le même temps, on procède à la correction de la bifidité nasale. Les suites opératoires sont simples. Le recul est de 5 ans, avec un développement psychomoteur de l’enfant normal. Conclusion: Ce cas clinique, en rapportant l’association de ces 2 malformations neurologique et faciale peu fréquentes, soulève la question de leur étiopathogénie. Nous insistons par ailleurs sur le fait qu’une IRM anté-natale peu sousestimer la fente osseuse médiane. D’autre part, la prise en charge par une équipe multidisciplinaire de ces enfants et de leurs parents, dès le temps anté-natal, permet une meilleure gestion de la pathologie dans son ensemble. [Copyright &y& Elsevier]

The aim of our study was to assess the utility and reliability of magnetic resonance imaging (MRI) in antenatal diagnosis of craniosynostosis. We retrospectively reviewed the MRI examinations of the head of 15 fetuses requested over a period of 11 years on the basis of sonographic suspicion of craniosynostosis. The postnatal diagnosis was available for 14 neonates. No termination of pregnancy was performed. There were four neonates with sporadic multisuture craniosynostoses, three of which were syndromic, including one Crouzon and one Pfeiffer syndrome. Eight neonates were normal, two showed cranial vault deformities without synostosis, and one was lost to follow-up. MRI showed a high predictive value for craniosynostosis, as there were no false-negative or false-positive diagnoses. However, the severity of the abnormalities were underestimated in two neonates. We suggest that prenatal MRI has diagnostic value when synostosis is suspected on ultrasonography. Moreover, MRI is accurate in the detection of associated brain abnormalities, which is an important prognostic issue in this diagnosis. Prenatal diagnosis of craniosynostosis is difficult and could benefit from three-dimensional ultrasonography and three-dimensional CT. [ABSTRACT FROM AUTHOR]

Cerebral cavernous malformations (CCMs) are hamartomatous vascular malformations characterized by abnormally enlarged capillary cavities without intervening brain parenchyma. They cause seizures and cerebral hemorrhages, which can result in focal neurological deficits. Three CCM loci have been mapped, and loss-of-function mutations were identified in the KRIT1 (CCM1) and MGC4607 (CCM2) genes. We report herein the identification of PDCD10 (programmed cell death 10) as the CCM3 gene. The CCM3 locus has been previously mapped to 3q26-27 within a 22-cM interval that is bracketed by D3S1 763 and D3S1262. We hypothesized that genomic deletions might occur at the CCM3 locus, as reported previously to occur at the CCM2 locus. Through high-density microsatellite genotyping of 20 families, we identified, in one family, null alleles that resulted from a deletion within a 4-Mb interval flanked by markers D3S3668 and D3S1614. This de novo deletion encompassed D3S1763, which strongly suggests that the CCM3 gene lies within a 970-kb region bracketed by D3SI 763 and D3S1614. Six additional distinct deleterious mutations within PDCD10, one of the five known genes mapped within this interval, were identified in seven families. Three of these mutations were nonsense mutations, and two led to an aberrant splicing of exon 9, with a frameshift and a longer open reading frame within exon 10. The last of the six mutations led to an aberrant splicing of exon 5, without frameshift. Three of these mutations occurred de novo. All of them cosegregated with the disease in the families and were not observed in 200 control chromosomes. PDCD10, also called "TFAR15," had been initially identified through a screening for genes differentially expressed during the induction of apoptosis in the TF-1 premyeloid cell line. It is highly conserved in both vertebrates and invertebrates. Its implication in cerebral cavernous malformations strongly suggests that it is a new player in vascular morpho- genesis and/or remodeling. [ABSTRACT FROM AUTHOR]

Craniosynostosis in newborns is caused by the premature closure of the cranial sutures leading to cranial vault deformity. It results in aesthetic imbalance and developmental disabilities and surgery is frequent during the first months of growth. Our study focused on scaphocephaly defined as the premature closure of the sagittal suture. We hypothesised that the effective mechanical properties of sutures were altered as compared to those of the parietal adjacent tissue considered as control. The population consisted of seven males and four females (mean age 4.9 months). Sixteen suture samples and thirty-four parietal tissue samples were harvested during corrective surgery and investigated by using three-point bending tests to obtain the structure-stiffness of specimens. An energy model was used to derive the effective Young's modulus. A histological study complemented the experimental protocol. Fused sutures were thicker than adjacent bone and the natural curvature of sutures did not influence the static mechanical response. The stiffness of stenotic sutures was significantly higher than that of the parietal bone. The effective Young's modulus of stenotic sutures was significantly lower than that of the parietal adjacent tissue. The parietal tissue showed a parallel bone architecture whereas the central stenotic tissue was disorganised with more vascularisation. The stenotic suture differed in structural and mechanical terms from the adjacent bone during calvarial growth in the first year of life. Our study emphasised the alteration of effective tissue properties in craniosynostosis. • Premature closure of sutures causes craniosynostosis and skull deformity. • Fused sutures were stiffer and Young's modules were lower than normality. • Exploration of suture mechanical response may contribute to craniostenosis aetiology. [ABSTRACT FROM AUTHOR]

Discusses the abstract of the study 'International Multicenter Study of Head Injury in Children,' by K.M. Leung, D. Fong et al, presented at the 6th Annual Scientific Meeting of the Hong Kong Neurosurgical Society held on December 4, 1999.