Ear Dysmorphism Associated with Cystic Hygroma Colli in Second-Trimester Fetuses

To investigate if fetuses with cystic hygroma colli have ear auricle dysmorphism, we studied 16 fetuses with cystic hygroma colli, all of which had 45,X karyotype, and 107 normal fetuses. All the specimens were second-trimester formalin-preserved human fetuses. The ear lengths and widths were measured and ear indices (length/width) calculated. There were no significant differences in the ear measurements of age-matched normal male and female fetuses (P >. 05). Ear growth was less linear in the cystic hygroma colli group than in the normal fetues; Pearson's coefficient. 45 vs. 87 for ear length, and r =. 77 vs. 88 for ear width. The mean (±SD) ear index of the normal fetuses was 1.56 ± 0.22 compared to 2.10 ± 0.36 of the cystic hygroma colli fetuses, P 2SD of gestational age norm) was observed in 6.3% (1/16) of the ear widths, 56.3% (9/16) of the ear lengths, and 62.5% (10/16) of the ear indices. We conclude that cystic hygoma colli fetuses with 45,X have unique ear auricle morphology.