P38.02: Aqueductal stenosis caused by fetal intracranial hemorrhage and leptomeningeal infection: two unusual cases of third trimester ventriculomegaly

Abstract

Objectives: The term macrocephaly signifies a head circumference (HC) that is more than 2 standard deviations above the mean or exceeds the 97th percentile. Benign familial macrocephaly is a dominantly or recessively inherited disorder in which the head size of otherwise normal newborn. In this study we report prenatal diagnosis of a benign familial macrocephaly case. Methods: The patient was a 20-year-old woman, gravida 1. She had an ultrasound examination at 11 weeks’ gestation. Ultrasound scanning at 18 weeks’ gestation showed a HC measurement above 97th percentile. Femoral length and abdomen circumference measurement were above 50th percentiles. Results: The serial scans demonstrated that HC had continued to growth above 97th percentile. Paternal HC was 62 cm (above 97th percentile) and family pedigree showed more than 14 other affected members with this disorder. At gestational age of 37+5 weeks, because of the large head size and premature rupture of membranes Cesarean section was performed and evaluation of the male infant at birth showed a HC 39 cm (above 98th percentile). No other physical abnormalities were detected. Follow-up evaluation by MRI and physical examination at 6 months of age showed a normal neurologic evaluation but persistent macrocephaly. Conclusion: In this disorder, serial measurement of HC demonstrates a proportional rather than an excessive rate of growth. In this condition, measurements of parental head size often reveal macrocephaly in one parent. This case report highlights the necessity of combining appropriate family history and serial measurement of HC for diagnosis of benign familial macrocephaly.