Table 1:

Cohort characteristics

Clinical Characteristics (n = 36)
Age at first imaging (months)19.6 (4.3–59.3)
Sex (F:M)25:11 (2.2:1)
Diagnosis18q deletion (18q-) - 23 (64) Trisomy 18 - 7/tetrasomy 18 - 1 (Total 8 [22]) Ring chromosome 18 - 4 (11)18q inversion 1 (3)
Clinical data (denominator indicates cases who underwent dedicated assessment for the specific feature and available documentation)
 Microcephalya13/19 (68)
 Short staturea13/14 (93)
 Visual impairment11/15 (73)
 Hearing impairment9/15 (60)
 Cleft palate4/12 (33)
 Epilepsy8/18 (44)
 Genitourinary9/14 (64)
 Cardiac11/16 (69)
Imaging characteristics (n = 36, 50 MRIs)
At least 1 abnormal MR imaging: 33/36 (92, n = 50 for the rows below)
 Abnormal white matter35 (70)
 Abnormal CC30 (60)
 Dysplastic/agenetic CC8 (16)
 CC-APD <3rd percentilea18/47 (38)
 Body and/or splenium thickness <3rd percentilea25/47 (53)
 APD pons <3rd percentilea10 (20)
 CCD vermis <3rd percentilea14 (28)
Other findings
 Periventricular nodular heterotopia3
 Ectopic posterior pituitary3
 Holoprosencephaly variant (thickened lamina rostralis and fused fornices, CNPAS with SMMCIb absent olfactory bulbs), aqueductal stenosis, polymicrogyria1 each

  • ↵a Criteria based on <3rd percentile for age- and sex-matched referenced data. Numbers in parentheses indicate percentages.

  • ↵b Congenital Nasal Pyriform Aperture Stenosis with Solitary Median Maxillary Central Incisor Syndrome.