Affiliation:
1. Richard D. Wood Jr. Center for Fetal Diagnosis and Treatment The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
2. Perelman School of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
3. Department of Radiology The Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
Abstract
ABSTRACTObjectiveTo determine the diagnostic performance of ultrasound markers associated with life‐limiting fetal skeletal dysplasia in a fortified cohort.MethodsRetrospective review from 2013 to 2023 of pregnancies with suspected fetal skeletal dysplasia. Ultrasound evaluation included measurements predictive of a life‐limiting dysplasia: thoracic circumference/abdominal circumference (TC/AC) < 0.6, femur length/abdominal circumference (FL/AC) < 0.16, and thoracic circumference (TC) < 2.5th percentile. Demographics, ultrasound findings, genetic testing, and fetal/neonatal outcome were reviewed.ResultsOf 96 fetuses with complete outcome data, 47 (49%) had a non‐life‐limiting dysplasia and 49 (51%) had a life‐limiting dysplasia. 22 (23%) had no life‐limiting markers, 42 (44%) had one, 27 (28%) had two, and 5 (5%) had three. FL/AC < 0.16 and TC < 2.5th percentile were associated with life‐limiting dysplasia (p < 0.001; p < 0.001), while TC/AC < 0.6 was rare and did not reach statistical significance (p = 0.056). The positive predictive value (PPV) for predicting life‐limiting dysplasia increased from 50% to 78% to 100% with one, two, or three markers. The PPV of the two life‐limiting markers was significantly higher in those diagnosed at < versus ≥ 28 weeks (90% vs. 43%, p = 0.02) but the analysis was limited by small numbers in the ≥ 28 weeks cohort. The negative predictive value of no life‐limiting markers was 91%.ConclusionsIn our cohort, the presence of two life‐limiting ultrasound markers prior to 28 weeks was highly suggestive of a life‐limiting dysplasia, whereas the absence of life‐limiting markers was strongly associated with a non‐life‐limiting dysplasia throughout gestation. Nonetheless, individual markers had a poor predictive value of lethality, and a life‐limiting diagnosis ≥ 28 weeks is challenging based on ultrasound markers alone. This highlights the importance of integrating thorough sonography, genetic testing, and balanced parental counseling.