OP15.07: Can syndromic macrocephaly be diagnosed in utero?

Abstract

of 103 babies (median 8 years, range 2-19 years) shows normal intellectual ability in 79 cases (76.6%). Prenatal VM correlates with postnatal IQ: babies with absent VM shows normal intellectual ability in 84.2% (mean IQ = 95.4), whereas babies with progressing prenatal VM had normal outcome in 66.6% (mean IQ = 85). The ability to walk is present in 63 cases (61.2%); the sfincterial function shows severe impairment in 64 cases (62.1%). In comparing 2 periods in our series, February 1980-June 1994 and July 1994-February 2010 Objectives: Ventricle measurements at the level of the atrium are routinely performed as part of routine prenatal ultrasound examination. Though this measurement may vary across GA, a measurement above 10 mm is usually considered as abnormal. It is also commonly consider that VL may vary according to fetal size and gender. This study was undertaken to evaluate the relationship of GA-adjusted VL with fetal gender and size. Methods: During a study period of four years, a single operator unaware of the subsequent analysis, prospectively and routinely performed cerebral ventricle width measurements at the level of the atrium. Measurements were transformed into Z-scores based on previously published charts. The relationship between VL Z-scores, fetal gender, fetal head circumference (HC) and estimated fetal weight (EFW) was investigated by means of robust regression. Results: VL Z-score was available in 4735 cases. Mean (SD) of VL Z-score was −0.003 ± 1.000. VL Z-score was significantly different according to fetal gender, HC Z-score and EFW Z-score. In multivariate analysis, gender (β = 0.16, P < 10-4) and HC Z-score (β = 0.17, P < 10-4) remained significant predictors of VL Z-score. Conclusions: Our findings support the usual belief that large for GA males have larger ventricle measurements. OP15.06Increasing of fetal intraorbital optic nerve diameter during pregnancy: evaluation by sonography Prenatal Medicine Unit, Modena and Reggio Emilia University, Modena, ItalyObjectives: To assess the diameter of fetal intraorbital portion of the optic nerve in different gestational ages. Methods: In this prospective study 41 fetuses from 19 to 37 gestational weeks were evaluated: 8 fetuses were at 19-20 gestational weeks, 4 at 25-27, 20 at 29-33 and 5 at 35-37 gestational weeks. During the standard two-dimensional examination the optic nerve was visualized in axial view of the brain in intraorbital portion and the diameter was measured. In one case of agenesis of cavum septum pellucidum the diameter of optic nerve was measured longitudinally starting from 20 to 35 gestational weeks in association with two RMI (resonance magnetic imaging) performed at 20 and 32 gestational weeks. Results: The mean value of the optic nerve diameter at 19-20 gestational weeks was 1.3 mm (0.9-1.8 mm), at 25-27 1.6 mm (1.4-1.9 mm), at 29-33 2.7 mm (2-3.3 mm) and at 35-37 2.8 mm (2.2-3.4 mm). In case of cavum septum pellucidum agenesis the diameter of the optic nerve increased from 1 mm at 20 gestational weeks to 2.1 mm at 28;...

Clinical and molecular data in cases of prenatal localized overgrowth disorder: major implication of genetic variants in PI3K‐AKT‐mTOR signaling pathway

“…Generally, MEG and HMEG are associated with macrocephaly, related to expansion of brain parenchyma, and do not show enlargement of subarachnoid spaces, intracranial tumors or abnormalities of the skull 4 . In contrast with MEG, in which overgrowth is diffuse and symmetrical, HMEG is defined by asymmetrical brain overgrowth, with midline shift 5 . Definitions of MEG and HMEG differ, depending on whether diagnostic criteria are based on imaging (ultrasound, magnetic resonance imaging (MRI)) or pathology 4–6 .…”

“…In contrast with MEG, in which overgrowth is diffuse and symmetrical, HMEG is defined by asymmetrical brain overgrowth, with midline shift 5 . Definitions of MEG and HMEG differ, depending on whether diagnostic criteria are based on imaging (ultrasound, magnetic resonance imaging (MRI)) or pathology 4–6 . Limb overgrowth involves bones and soft tissue (subcutaneous fatty tissue and muscle), and may be associated with slow‐flow vascular malformations, particularly lymphatic malformations (LM) 7 .…”

Fetal macrocephaly: Pathophysiology, prenatal diagnosis and management

“…As in osteodystrophies, these often become apparent later in infancy, although some can present prenatally. Examples include mucopolysaccharidoses and other lysosomal storage disorders, as well as Alexander (GFAP mutation), Canavan disease (ASPA deficiency) and megalocephalic leukoencephalopathy with subcortical cysts (MLC1) 4,25 . Metabolic storage diseases such as mucopolysaccharidoses and mucolipidoses can also produce macrocephaly due to the deposition of abnormal metabolites in the meninges and arachnoid granulation, resulting in cerebrospinal fluid malabsorption 26 …”

Antenatal counselling for prospective parents whose fetus has a neurological anomaly: part 2, risks of adverse outcome in common anomalies

“…Most cases are familial in origin, and it is worth measuring and plotting the biological parents’ head circumference to determine if their head sizes are large. Reported developmental outcomes from small studies are usually typical in isolated cases 54–56 …”

“…Reported developmental outcomes from small studies are usually typical in isolated cases. [54][55][56] Where there are other malformations, possible aetiologies include Sotos syndrome (NSD1 gene), mutations in the NFIX gene, neurofibromatosis type 1, Klippel-Trenaunay syndrome, conditions associated with capillary malformations, including the macrocephaly-capillarymalformation syndrome, and Cowden syndrome, which is associated with hamartomas, and mutations in the PTEN gene. 57,58 Other aetiologies include fetal tumours, expanding intracranial cysts, megalencephaly, and glutaric aciduria type 1.…”