Category: Ultrasound/Imaging
Poster Session IV
Obtaining an accurate midsagittal plane is paramount to providing consistent detailed first-trimester fetal neurosonography. The definitive midsagittal plane is only identified when the falx cerebri is seen as a midline echogenicity that extends from the midbrain to the cranium. Since this is not currently required as criteria for nuchal translucency, it is possible to have a slight cranial deviation during the 11-13 6/7 week NT scan. Our goal was to determine if this important marker is consistently seen when criteria for nuchal translucency are utilized.
Study Design:
Patients undergoing nuchal translucency imaging from 11 to 13-6/7 weeks at a single MFM referral practice were evaluated from 2020 to present. Presence of the falx cerebri in the midsagittal plane was confirmed if there was complete echogenicity from midbrain to cranium. Deviation from the midline was confirmed if the choroid plexus was seen and the echolucent lateral ventricle was interposed between the choroid and the cranium. The "flash" is obtained as the transducer is angled through the midsagittal midline.
Results:
There were 2567 patients reviewed. The midline echogenic falx was documented in only 23% (590/2567) of the images meeting NT criteria. There was significant improvement from 18.5% (404/2182) in 2021 to 48.3% (186/385) in the first few months of 2022 (p < 0.05).
Conclusion:
The true mid-sagittal plane is a necessity for consistent detailed first-trimester neurosonography. Visualization of the falx cerebri confirms the true midsagittal plane for detailed fetal CNS assessment. This ultrasound marker can be missed when incorporating the typical nuchal translucency criteria. We conclude that the falx flash should be a necessary criterion in detailed first-trimester sonography.
David N. Jackson, MD (he/him/his)
MFM
High Risk Pregnancy Center
Las Vegas, Nevada, United States
Bobby Brar, MD (he/him/his)
Department of Obstetrics and Gynecology, Johns Hopkins University School of Medicine
Baltimore, Maryland, United States
Pooja Patil, MD
Department of Obstetrics and Gynecology, University of Nevada Las Vegas School of Medicine
Las Vegas, Nevada, United States
Paula Chenevey, RDMS
High Risk Pregnancy Center
Las Vegas, Nevada, United States
Parker Sheldon, MD
George Washington University Milken Institute of Public Health
Washington, District of Columbia, United States
Maryam Farooqui, BS
MS 3
Touro University Nevada
Henderson, Nevada, United States
Spencer Klatt, BS
MS 1
Touro University Nevada
Las Vegas, Nevada, United States
Garrett K. Lam, MD
High Risk Pregnancy Center
Draper, Utah, United States