RESUMEN
OBJECTIVE: To measure prospectively apparent diffusion coefficient (ADC) values between 28 and 32 weeks of gestation in different cerebral territories of fetuses with estimated fetal weight (EFW) ≤ 5th centile, and analyze their association with adverse perinatal outcome. METHODS: This was a prospective study involving six tertiary-level perinatal centers. In the period 22 November 2016 to 11 September 2017, we included singleton, small-for-gestational-age (SGA) fetuses with EFW ≤ 5th percentile, between 28 and 32 weeks of gestation, regardless of the umbilical artery Doppler and maternal uterine artery Doppler findings. A fetal magnetic resonance imaging (MRI) examination with diffusion-weighted sequences (DWI) was performed within 14 days following inclusion and before 32 weeks. ADC values were calculated in the frontal and occipital white matter, basal ganglia and cerebellar hemispheres. An ultrasound examination was performed within 1 week prior to the MRI examination. The primary outcome was a composite measure of adverse perinatal outcome, defined as any of the following: perinatal death; admission to neonatal intensive care unit with mechanical ventilation > 48 h; necrotizing enterocolitis; Grade III-IV intraventricular hemorrhage; periventricular leukomalacia. A univariate comparison of median ADC values in all cerebral territories between fetuses with and those without adverse perinatal outcome was performed. The association between ADC values and adverse perinatal outcome was then analyzed using multilevel logistic regression models to adjust for other common prognostic factors for growth-restricted fetuses. RESULTS: MRI was performed in 64 patients, of whom five were excluded owing to fetal movement artifacts on DWI and two were excluded for termination of pregnancy with no link to fetal growth restriction (FGR). One intrauterine death occurred secondary to severe FGR. Among the 56 liveborn neonates, delivered at a mean ± SD gestational age of 33.6 ± 3.0 weeks, with a mean birth weight of 1441 ± 566 g, four neonatal deaths occurred. In addition, two neonates required prolonged mechanical ventilation, one of whom also developed necrotizing enterocolitis. Overall, therefore, seven out of 57 (12.3%) cases had an adverse perinatal outcome (95% CI, 3.8-20.8%). The ADC values in the frontal region were significantly lower in the group with adverse perinatal outcome vs those in the group with favorable outcome (mean values of both hemispheres, 1.68 vs 1.78 × 10-3 mm2 /s; P = 0.04). No significant difference in ADC values was observed between the two groups in any other cerebral territory. A cut-off value of 1.70 × 10-3 mm2 /s was associated with a sensitivity of 57% (95% CI, 18-90%), a specificity of 78% (95% CI, 63-88%), a positive predictive value of 27% (95% CI, 8-55%) and a negative predictive value of 93% (95% CI, 80-98%) for the prediction of adverse perinatal outcome. A mean frontal ADC value < 1.70 × 10-3 mm2 /s was not associated significantly with an increased risk of adverse perinatal outcome, either in the univariate analysis (P = 0.07), or when adjusting for gestational age at MRI and fetal sex (odds ratio (OR), 6.06 (95% CI, 0.9-37.1), P = 0.051) or for umbilical artery Doppler (OR, 6.08 (95% CI, 0.89-41.44)). CONCLUSION: This first prospective, multicenter, cohort study using DWI in the setting of SGA found lower ADC values in the frontal white-matter territory in fetuses with, compared with those without, adverse perinatal outcome. To determine the prognostic value of these changes, further standardized evaluation of the neurodevelopment of children born with growth restriction is required. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/estadística & datos numéricos , Retardo del Crecimiento Fetal/diagnóstico por imagen , Resultado del Embarazo/epidemiología , Diagnóstico Prenatal/estadística & datos numéricos , Adulto , Encéfalo/embriología , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Peso Fetal , Edad Gestacional , Humanos , Recién Nacido Pequeño para la Edad Gestacional , Valor Predictivo de las Pruebas , Embarazo , Tercer Trimestre del Embarazo , Diagnóstico Prenatal/métodos , Pronóstico , Estudios Prospectivos , Ultrasonografía Doppler , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagenRESUMEN
OBJECTIVES: To assess the added value of intravenous gadolinium injection to magnetic resonance imaging (MRI) -based diagnosis of abnormally invasive placenta (AIP) and to examine this in relation to the radiologist's experience. DESIGN: Retrospective study. SETTING: Between March 2009 and October 2012, 31 pregnant women who had previous caesarean delivery together with a placenta praevia and suspected placenta accreta on ultrasound in the third trimester of pregnancy. POPULATION: All were offered MRI examination, and made aware of the limited (but so far reassuring) data regarding fetal safety of gadolinium. Twenty pregnant women agreed to undergo prenatal MRI (1.5 T), with and without gadolinium injection. METHODS: Two sets of MRI examinations without and with gadolinium were reviewed independently 2 months apart by two senior and two junior radiologists; all were blinded to the outcome (known in all cases). Histopathological findings and clinical signs of AIP were considered as the defining criteria of diagnosis. MAIN OUTCOME MEASURE: accuracy of MRI with and without gadolinium was assessed. RESULTS: Eight of the 20 women had confirmed abnormal placental invasion. The overall performance of both sets of readers in detecting AIP increased with gadolinium-sensitivity and specificity of 75.0% (42.0-100%) and 47.9% (19.9-75.9%) increasing to 87.5% (57.1-100%) and 60.4% (33.9-86.9%), respectively (P = 0.04). The added value of gadolinium remained irrespective of radiologist's experience, although senior radiologists performed better overall (sensitivity and specificity of 87.5% and 62.5% versus 62.5% and 33.3%, respectively, increasing with injection to 93.8% and 70.8% versus 81.3% and 50%, respectively; P < 10-4 ). CONCLUSION: There was an association between gadolinium use and improvement in MRI-based diagnostic accuracy for the diagnosis of AIP, for both junior and senior radiologists. TWEETABLE ABSTRACT: Gadolinium injection improves MRI performance of radiologists for the diagnosis of placenta accreta.
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Gadolinio , Imagen por Resonancia Magnética/métodos , Placenta Accreta/diagnóstico , Placenta Previa/diagnóstico , Placenta/patología , Administración Intravenosa , Adulto , Medios de Contraste , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Embarazo de Alto Riesgo , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía Prenatal/métodosRESUMEN
PURPOSE: To determine the reliability and variations of apparent diffusion coefficient (ADC) values in normal fetuses. Materials and methods. Retrospective study (2007-2008) on 22 normal fetal MR examinations, performed between 30 and 34 of gestation, using a routine protocol (T1W and T2W images in 3 planes, b=1,000 diffusion-weighted imaging) without sedation. ADC values were measured by placing 3 adjacent regions of interest (ROI) including a centrally located ROI over the right frontal and occipital white matter (6 ROI). STATISTICAL ANALYSIS: reproducibility of adjacent ADC values (intraclass correlation coefficient: ICC) and comparison between frontal and occipital ADC values (Wilcoxon). RESULTS: The mean ADC value was 1.78 mm(2)/s for the frontal white matter (+ or - 0.10) and 1.66 mm(2)/s for the occipital white matter (+ or - 0.12) with excellent reproducibility (ICC=0.91 in the frontal lobe) and good reproducibility for adjacent measurements (ICC=0.7). A linear inverse correlation existed between ADC values and gestational age in the occipital lobes, and a significant fronto-occipital gradient existed after 32 weeks of gestational age. CONCLUSION: ADC value measurements are reliable and inversely correlated with gestational age due to fetal brain maturation. The existence of a fronto-occipital gradient after 32 weeks of gestational age could be a marker of normal maturation used in clinical practice.
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Encéfalo/embriología , Encéfalo/crecimiento & desarrollo , Imagen de Difusión por Resonancia Magnética , Feto/embriología , Humanos , Estudios RetrospectivosRESUMEN
PURPOSE: To determine the imaging features of hemorrhagic infarction in neonates. PATIENTS AND METHODS: Retrospective study (1998-2008) of 19 children (17 premature and 2 term deliveries) with early lobar hyperechogenicity on transfontanel US (TFUS). Group I: 11 born infants with clinical as well as TFUS and MRI follow-up. Group II: 8 premature infants deceased within a week from multisystem pathology, with neuropathological study available in 3 cases. RESULTS: Group I (n=11): periventricular hyperechogenicity in a frontal (7), frontoparietal (2), parietooccipital (1) and temporoparietal (1) distribution with developing cavitary change (n=6). MRI showed a cortex sparing intraparenchymal hematoma. Group II (n=8): periventricular hyperechogenicity in a frontal (4), frontoparietal or parietal (3) and occipital (1) with developing cavitary change (3). Neuropathological examination showed characteristic lesions of venous hemorrhagic infarction. Clinical outcome was generally favorable for the surviving infants with contralateral motor deficit (n=5) non-correlated to the extent of the initial lesions. CONCLUSION: Venous hemorrhagic infarction mainly affetcs premature infants and typically involves the periventricular frontal white matter. Prognosis is generally favorable. It is thus important to differentiate this entity from asymmetrical cystic periventricular leukomalacia with much different prognosis.
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Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/diagnóstico , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/diagnóstico , Ecoencefalografía/métodos , Hematoma/diagnóstico por imagen , Hematoma/diagnóstico , Enfermedades del Prematuro/diagnóstico por imagen , Enfermedades del Prematuro/diagnóstico , Imagen por Resonancia Magnética , Peso al Nacer , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Evaluación de Resultado en la Atención de Salud , Estudios RetrospectivosAsunto(s)
Enfermedades Fetales/diagnóstico por imagen , Orofaringe/diagnóstico por imagen , Teratoma/diagnóstico por imagen , Adulto , Obstrucción de las Vías Aéreas/prevención & control , Obstrucción de las Vías Aéreas/cirugía , Diagnóstico Diferencial , Femenino , Edad Gestacional , Humanos , Recién Nacido , Imagen por Resonancia Magnética/métodos , Orofaringe/patología , Embarazo , Teratoma/embriología , Ultrasonografía PrenatalRESUMEN
Fetal MRI is a specific imaging modality, always performed after a reference ultrasound examination. The decision to perform an MRI-scan must take into account the anxiety constantly generated by the need for this unusual examination during pregnancy. To date, no side-effect associated with 1.5 tesla magnets has been described. Compared to ultrasonography, fetal brain MRI provides better contrast between grey and white matter, as well as better delineation of the brainstem (pontic curvature) and the cerebellum (lobules and fissures). However, it often remains difficult to inform parents about prognosis. Thereby, it is of utmost importance to be familiar with the definite criteria associated with a poor neurological prognosis such as lack of pontic curvature or as diffuse or bilateral cortical malformations. This has to be considered within the framework of French regulations which allow pregnancy termination with no time limit. The optimal timing to perform a fetal MRI-scan depends on the context. The period between 27 and 30 weeks of gestation is a good balance between gestational age and gyration or sulcation development. The main ultrasonographic findings requiring MRI are ventriculomegalies and posterior fossa abnormalities. MRI exploration can sometimes be performed despite a normal ultrasonography in case of genetic disorders such as tuberous sclerosis and lissencephalies. In addition to its diagnostic value towards decision to terminate pregnancy, fetal MRI can be used as "in vivo autopsy", in case of expected technical difficulties or refusal of post-abortion examinations by relatives. Technical advances (real time and specific sequences like diffusion tensor and spectroscopy) and prospective clinical studies will probably improve the efficiency of this method to assess neurological prognosis.
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Encéfalo/embriología , Feto/anatomía & histología , Imagen por Resonancia Magnética/métodos , Encéfalo/anomalías , Encéfalo/anatomía & histología , Encéfalo/patología , Ventrículos Cerebrales/anatomía & histología , Ventrículos Cerebrales/embriología , Cuerpo Calloso/anatomía & histología , Cuerpo Calloso/embriología , Femenino , Edad Gestacional , Humanos , Vaina de Mielina , Embarazo , Tabique Pelúcido/anomalías , Tabique Pelúcido/embriología , Tabique Pelúcido/patologíaAsunto(s)
Labio Leporino/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Procedimientos de Cirugía Plástica/métodos , Lengua/diagnóstico por imagen , Labio Leporino/embriología , Labio Leporino/cirugía , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Mandíbula/anomalías , Mandíbula/embriología , Mandíbula/cirugía , Embarazo , Tercer Trimestre del Embarazo , Factores de Tiempo , Lengua/anomalías , Lengua/embriología , Lengua/cirugía , Resultado del Tratamiento , Ultrasonografía , Adulto JovenRESUMEN
The accurate morphological exploration of the brain is a major challenge in neonatology that advances in magnetic resonance imaging (MRI) can now provide. MRI is the gold standard if an hypoxic ischemic pathology is suspected in a full term neonate. In prematures, the specific role of MRI remains to be defined, secondary to US in any case. We present a state of the art of hardware and software technical developments in MRI. The increase in magnetic field strength (3 tesla) and the emergence of new MRI sequences provide access to new information. They both have positive and negative consequences on the daily clinical data acquisition use. The semiology of brain imaging in full term newborns and prematures is more extensive and complex and thereby more difficult to interpret. The segmentation of different brain structures in the newborn, even very premature, is now available. It is now possible to dissociate the cortex and basal ganglia from the cerebral white matter, to calculate the volume of anatomical structures, which improves the morphometric quantification and the understanding of the normal and abnormal brain development. MRI is a powerful tool to analyze the neonatal brain. The relevance of the diagnostic contribution requires an adaptation of the parameters of the sequences to acquire and of the image processing methods.
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Encéfalo/patología , Imagen por Resonancia Magnética/tendencias , Encéfalo/crecimiento & desarrollo , Encefalopatías/diagnóstico , Humanos , Recién Nacido , Recien Nacido Prematuro , Imagen por Resonancia Magnética/métodosRESUMEN
Ultrasound is the first-line imaging study of the fetal brain performed at 12, 22 and 32 weeks of gestation. The very structured evaluation of biometric and morphological data, facilitated by the use of a checklist, ensures a high quality examination. All patients where an anomaly of any key element is suspected should be referred to a center dedicated to prenatal diagnosis for confirmation irrespective of the gestational age. Prenatal diagnosis plays a significant role in France since medical interruption of pregnancy until term is authorized.
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Encéfalo/anomalías , Ecoencefalografía , Ultrasonografía Prenatal , Femenino , Edad Gestacional , Humanos , EmbarazoRESUMEN
The challenge of fetal imaging is crucial in France because of the law allowing termination of pregnancy (TOP) until the end of pregnancy. Fetal MRI is an imaging tool always used after ultrasonography (US). Its indications are pertinent only in relation with a prenatal center. Fetal MRI raises parental anxiety to take into account before and during the examination. To date, cerebral indications are predominant. Fetal brain maturation can be followed with MRI (gyration and myelination) but the optimal moment of a fetal MRI depends on the suspected pathology: the analysis of gyration is possible only by 28 WG, as before this time, the brain surface is smooth; in contrast, the posterior fossa demonstrates a definitive morphology since 20 WG. The ventriculomegaly is the most frequent call sign and includes various entities. MRI can disclose associated abnormalities (heterotopia, gyration, white matter, median line), which can suggest diagnosis and pronosis. A cystic pouch of the posterior fossa must lead to a careful analysis of cerebellum and brainstem to approach the diagnosis. Extracerebral indications become progressively larger and fetal MRI is a useful complementary tool after US to study tumors, particularly cervicothoracic masses. MRI can help to assess the level of bowel obstruction but multiple stenosis and post-stenotic bowel is difficult to evaluate. Fetal MRI can help to evaluate bilateral important pyelocalicial dilatation.
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Encéfalo/anomalías , Fosa Craneal Posterior/anomalías , Feto/anomalías , Imagen por Resonancia Magnética , Neoplasias/diagnóstico , Ultrasonografía Prenatal , Ventrículos Cerebrales/anomalías , Femenino , Humanos , Obstrucción Intestinal/diagnóstico , Valor Predictivo de las Pruebas , Embarazo , Diagnóstico Prenatal , Pielonefritis/diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía Prenatal/métodosAsunto(s)
Enteritis/complicaciones , Hipocalcemia/complicaciones , Hipoparatiroidismo/etiología , Cloruro de Magnesio/uso terapéutico , Deficiencia de Magnesio/complicaciones , Traumatismos por Radiación/complicaciones , Enfermedad Aguda , Anciano , Femenino , Humanos , Hipocalcemia/sangre , Hipocalcemia/tratamiento farmacológico , Hipoparatiroidismo/sangre , Hipoparatiroidismo/tratamiento farmacológico , Deficiencia de Magnesio/sangre , Deficiencia de Magnesio/tratamiento farmacológicoRESUMEN
We report the first case of infantile hemangiopericytoma explored prenatally by fetal ultrasonography and magnetic resonance imaging (MRI). It was associated with a developmental cerebral anomaly identified on MRI. The largest lesions of the multifocal hemangiopericytoma were located in the soft tissue adjacent to the left temporal bone, and smaller lesions were found in the lumbar area and in the retroperitoneum. MRI showed no connection between the tumor and the fetal brain but there was anomalous cerebral gyration in the region and the Sylvian fissure beneath the tumor was enlarged. The pregnancy was terminated because of the severe brain anomalies and postmortem examination confirmed the prenatal findings. Microscopic analysis of the tumor tissue showed branching vessels which are typical of hemangiopericytoma. The lesions in our case occurred in association with macrosomia with visceromegaly detected at autopsy, suggesting a possible role of tumor suppressor genes.
Asunto(s)
Anomalías Múltiples/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Encéfalo/anomalías , Hemangiopericitoma/diagnóstico por imagen , Imagen por Resonancia Magnética , Ultrasonografía Prenatal/métodos , Anomalías Múltiples/patología , Aborto Terapéutico , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/patología , Ecoencefalografía , Femenino , Macrosomía Fetal/patología , Hemangiopericitoma/complicaciones , Hemangiopericitoma/patología , Humanos , Masculino , Embarazo , Tercer Trimestre del Embarazo , Vísceras/anomalíasRESUMEN
We describe two unusual cases of congenital toxoplasmosis, one occurring after preconception maternal infection with cervical adenopathies and the other occurring after maternal infection at the very end of pregnancy with maternal seronegativity at delivery. These documented cases of congenital toxoplasmosis demonstrate the value of extending the serologic monitoring period during pregnancy, according to the individual clinical context.