Visualization of the fetal lip and palate: is brain-targeted MRI reliable?

Objective : To evaluate the ability of brain-targeted magnetic resonance imaging (MRI) to assess the anatomy of the fetal upper lip and palate. Design : Two independent readers made a blind retrospective review of 60 brain-targeted MRIs of fetuses from 20 to 38 gestational weeks (GW). Fifty-five MRIs were normal and five had orofacial anomalies, including one isolated cleft lip and four cleft lip and palate. Both normal and cleft MRIs had postnatal confirmation. The upper lip, primary palate, secondary palate, and nasal septum were scored into four levels, from evidently normal to evidently abnormal. In case of a suspected pathology, the readers attempted a diagnosis. Setting : Collaboration between a university hospital and a large private practice MRI center. Results : Interobserver agreement (weighted kappa) was 0.79 for the upper lip, 0.70 for the primary palate, 0.86 for the secondary palate, and 0.90 for the nasal septum. The scoring levels of the readers did not change significantly across gestational age. Normality was correctly scored in 96% to 100% of the normal lips and primary palates and in 93% to 97% of the normal secondary palates depending on the reader. A deviated septum was only scored in two fetuses with unilateral cleft palates. The readers identified all pathological cases. Conclusion : Brain-targeted fetal MRI in experienced hands seems to be highly accurate for the evaluation of the lip and palate in fetuses above 20 GW, regardless of gestational age. The assessment of the secondary palate may be slightly more limited than the lip or primary palate.

[Merosin-positive congenital muscular dystrophy, white matter abnormalities, and bilateral posterior occipital cortical dysplasia]. / Distrofia muscular congénita merosina positiva, anormalidades da substância branca e displasia cortical occipital posterior bilateral.

Congenital muscular dystrophy (CMD) is one of the most frequent dystrophies of childhood, which is commonly characterized by neonatal muscle impairment with or without clinical evidence of central nervous system involvement. CMDs were classified into five clinically distinct forms: the two classical CMDs with and without deficit of the a2 laminin chain (merosin) caused by mutations on chromosome 6q2, the Fukuyama CMD (severe form, initially described in Japanese patients and recently linked to the chromosome 9q31-33), Walker-Warburg syndrome and the muscle-eye-brain disease described in Finnish patients. The majority of these forms have severe clinical and imagiological involvement of SNC. This aspect is rarely observed on classical CMD, particularly in the merosin-positive form. We describe a case of a 28 year-old woman, with clinical and histopathological signs of classical CMD merosin-positive (no deficient), without mental retardation, but with epilepsy. MRI T2 weighted images, revealed diffuse and symetrical high signal white matter of both cerebral hemispheres, affecting corpos calosum, posterior arms of internal capsules and the piramidal tract to mesencephalon. It also disclosed diffuse and symetrical high signal of basal ganglia, specially, the head of caudate nuclei. These were associated with bilateral occipital posterior cortical dysplasia. The observed imagiological pattern could represent a new subtype of CMD, hybrid between classical CMD and the severe forms, however it is not clear where it fits in the spectrum. This case denotes the possible envolvement of SNC in patients merosin-positives. Based on this findings we suggest doing MRI scans to all patients with CMD no deficient in merosin.

[Choroidal type aneurysmal malformation of the vein of Galen associated with Dandy-Walker malformation in an adult]. / Malformação aneurismática da veia de Galeno do tipo coroidal num adulto associada a malformação de Dandy-Walker.

Lasjaunias differentiated true vein of Galen aneurysmal malformations (MAVG), which drain to the median prosencephalic vein of Markowski, the embryonic precursor of the vein of Galen, from the aneurysmal dilatations of vein of Galen (VGDA), which reveal venous drainage into a dilated vein of Galen, but already formed. In angioarchitectural terms, MAVG can still be divided in two subtypes: the mural form and the choroidal form, the most common. The authors describe the clinical case of a 18 years-old female, without symptoms until July 2001, who presented an episode of impaired equilibrium associated with vomits and non-specific vision disturbances. This episode had an approximate duration of 6-8 hours with complete recovery. Neuroimaging studies were performed including CT, MRI and digital angiography, disclosed an aneurysmal vein of Galen malformation of choroidal type and Dandy-Walker malformation, association that the authors couldn't found so far described in the literature.