MASTERCLASS: NEUROLOGÍA FETALTRANSTORNOS DE DESARROLLO CORTICAL

*ENFASIS EN MICROCEFALIAADELITA HÍJAR SIFUENTES

GINECÓLOGA – OBSTETRA

FELLOW MEDICINA MATERNO FETAL

ULTRASONIDO EN GINECO OBSTETRICIA Y DIAGNÓSTICO PRENATAL DE III NIVEL

(Clínica Universitaria Colombia – Fundación Universitaria Dexeus)

NEUROSONOGRAFÍA FETAL – NEUROLOGÍA FETAL

(Maternal Fetal Medicine Group)

ECOCARDIOGRAFÍA FETAL

(Clínica Universitaria Colombia – Fundación Clinic de Barcelona)

SERVICIO DE MEDICINA FETAL HONADOMANI SAN BARTOLOMÉ

CLÍNICA SAN FELIPE

OCTUBRE 2016

TRANSTORNOS DEL DESARROLLO CORTICAL• El desarrollo de la corteza cerebral fetal y la formación de giros y

sulcos es un proceso ordenado que se superpone con hitos bien definidos.

• Este proceso incluye:• Proliferación de neuronas y células gliales• Migración desde la zona periventricular• Organización de neuronas

TRANSTORNOS DEL DESARROLLO CORTICAL• Injurias durante este proceso produce un amplio rango de

malformaciones corticales que podrían devenir en déficit neurológico y/o convulsiones.

• Las malformaciones del desarrollo cortical podrían ser debido a:• Factores genéticos• Lesiones prenatales

• Trauma• Infecciones• Teratógenos

• The cerebral cortex is a modular structure: modules of neurons are induced in a neuroepithelial sheet and subsequently differentiate, migrate and organize into a functioning cerebral cortex.

• Neuronal induction is regulated by interplay between intrinsic genetic mechanisms and extrinsic information relayed to cortex by thalamocortical input and other, largely unknown, factors.

• Although details of the neural cell proliferation differ among mammalian species.

HISTOLOGÍA: CORTEZA CEREBRAL FETAL

Group I: malformations secondary to abnormal neuronal and glial proliferation or apoptosis• Groups I.A and III.D: microcephaly• Group I.B: megalencephalies• Group I.C: cortical dysgeneses with abnormal cell proliferationGroup II: malformations due to abnormal neuronal migrationA. Lissencephaly/subcortical band heterotopia. B. Cobblestone complex/ congenital muscular dystrophy syndromes.C. Heterotopia: subependymal, subcortical, marginal. Group III: malformations secondary to abnormal postmigrational developmentD. Polymicrogyria and schizencephaly. E. Cortical dysplasia without balloon cells. F. Microdysgenesis.

SIGNOS ECOGRÁFICOS DE MDC

TRANSTORNOS DE PROLIFERACIÓN: MICROCEFALIA• Antenatally is even more difficult, because affected fetuses have usually

normal cranial measurements in early gestation, that only decline in late gestation or after birth.

• The incidence is estimated to be 1.6 per 1000 singlebirth deliveries. Only 14 % of all microcephalic infants diagnosed by the first year of age had been detected at birth.

• The available literature suggests that the risk of mental retardation with an head circumference between – 2 and – 3 SDs is in the range of 10-30%, rising to 50-60% for measurements below – 3 SDs.

abnormal neurologic

development

small head

MICROCEPHALY

G.MALINGER G.MALINGER

G.PILU

Daniel-Spiegel et al—Establishment of Fetal Biometric Charts Using Quantile Regression Analysis. J Ultrasound Med 2013; 32:23–33 | 0278-4297

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TRANSTORNOS DE PROLIFERACIÓN: MACROCEFALIA• Head circumference above the 98th percentile or more than 2

standard deviations above the mean.

• Macrocephaly is relatively frequent in children and adults and is a common cause for genetic consultation.

• The diagnosis assumes that other obvious causes of head enlargement, such as hydrocephalus and cerebral tumors, have been excluded. Usually, macrocephaly is familial and benign and frequently it manifests only late in pregnancy or after delivery.

TRANSTORNOS DE PROLIFERACIÓN: MACROCEFALIA

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TRANSTORNOS DE PROLIFERACIÓN: HEMIMEGALENCEFALIA• Sobrecrecimiento de un hemisferio cerebral

Aislado (50%) o asociado a síndromes neurocutáneos.

• Clínica: ConvulsionesHemiparesia Retraso mental Hemihipertrofia en resto del cuerpo

Unilateral hypertrophy of the affected hemisphere, often associated with ipsilateral ventricular dilatation and midline shift.May be hemihypertrophy of the cerebellum, brainstem and body.Thought to occur as a result of an insult to the germinal matrix between 8 and 16 post menstrual weeks of gestation.May find focal increased echogenicity of the affected hemisphere.No abnormal karyotypic abnormality has been described.

TRANSTORNOS DE MIGRACIÓN

TRASNTORNOS DE MIGRACIÓN: LISENCEFALIA

Lissencephaly, type I is characterized by agyria with or without pachygyria, a wide cortical mantle and minimal or no hydrocephalus. Four layer cortex.· Miller-Dieker syndrome (17p13 deletion) has lissencephaly combined with dysmorphic facial features and other possible associated anomalies.· Norman-Roberts syndrome· Isolated type I lissencephaly

Lissencephaly, type II. Vascular bundles and fibroglial tissue are present in the cortex and subarachnoid space. Lissencephaly, type II typically has hydrocephalus and additional serious central nervous system defects. It is usually part of a syndrome.· HARD+/-E syndrome, an acronym for Hydrocephalus, Agyri, Retinal dysplasia, Encephalocele (Walker-Warburg syndrome) · COMS (Cerebro-oculomuscular syndrome)· Other subtypes of type II lissencephaly are possible

Lissencephaly is found in Neu-Laxova syndrome, lethal autosomal recessively inherited disorder consisting of growth retardation, microcephaly, lissencephaly, corpus callosum agenesis, intracranial calcifications, cerebellar hypoplasia, facial dysmorphism, microophthalmia, exophthalmus, cataracts, absent eyelids, hydrops, ichthyosis, contractures of extremities and syndactyly.

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• Malformación severa de corteza cerebral, que resulta de falla en migración neuronal durante el 3° y 4° mes de gestación.• Clínica:

Retraso psicomotor severoRetraso del desarrolloConvulsionesRetraso en crecimiento

• Este defecto acarrea un mal pronóstico del RN, con RM y alta tasa de recurrencia, si está ligado a defectos genéticos.

TRANSTORNOS DE MIGRACIÓN: HETEROTOPIA (CORTICAL – PERIVENTRICULAR)

TRANSTORNOS DE ORGANIZACIÓN

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