Dangling Choroid Plexus: An Early Sign of Fetal Anomaly

Area of Science:

• Prenatal diagnosis
• Fetal medicine
• Medical imaging

Background:

• The dangling choroid plexus sign is a potential indicator of fetal abnormalities.
• Establishing normal ranges for fetal ventricular measurements is crucial for accurate diagnosis.

Purpose of the Study:

• To investigate the association between the dangling choroid plexus sign and fetal abnormalities.
• To define normal lateral ventricular width and choroid plexus-to-ventricle ratio at 14-17 weeks gestation.

Main Methods:

• Retrospective analysis of ultrasound images from two tertiary fetal medicine centers.
• Inclusion of routine scans and assessments of high-risk pregnancies.
• Determination of normal ventricular measurements using a cohort of unaffected fetuses.

Main Results:

• Normal mean lateral ventricular width: 6.90 mm; mean choroid plexus-to-ventricle ratio: 0.85.
• Dangling choroid plexus identified in 0.16% of routine and 3.6% of high-risk scans.
• 37 of 38 cases with dangling choroid plexus showed structural defects, chromosomal, or genetic abnormalities, including trisomy 21.

Conclusions:

• The dangling choroid plexus sign is a significant sonographic marker for fetal abnormalities.
• Its presence necessitates detailed anatomical evaluation and consideration of genetic testing.
• Normal ranges for ventricular measurements were established for early fetal anatomy scans.