Many infants prenatally exposed to high levels of alcohol show one particular anomaly of the corpus callosum.
BACKGROUND
Effects of prenatal alcohol exposure on the brain are seen at every age. The earlier they can be quantified, the better the prognosis for the affected child. Here we show measurable alcohol effects at birth on a structure currently used for nosology only much later in life.


METHODS
Midline shape of the corpus callosum was imaged in infants via averaged unwarped transfontanelle ultrasound. We compared measures of these shapes among 23 infants prenatally exposed to high levels of alcohol and 21 infants unexposed to alcohol or only lightly exposed.


RESULTS
A particular feature of the corpus callosum, the appearance of a "hook" (obtuse angle) between the splenium and the long diameter of the arch in this plane, is strongly associated with prenatal alcohol exposure. In half of the high-exposed infants, the splenium angle is larger than in any of the unexposed brains. Simply characterizing this angle as less than or greater than 90 degrees detects 12 of the 23 exposed infants as anomalous with only 1 false positive among the unexposed. This apparently direct effect of prenatal ethanol exposure on the details of the callosum in about half the at-risk subjects cannot be attributed to any of several plausible competing exposures or other confounding factors applying during or after gestation.


CONCLUSIONS
An average of the images for the unexposed subjects has the geometry of textbook images of normal babies; but the average for the subgroup of high-angle subjects may serve as a template or guide to this regional damage parallel to the familiar photographic exemplars that help to assess facial signs.
Bookstein
Fred L
FL
Fetal Alcohol and Drug Unit, Department of Psychiatry and Behavioral Sciences, The University of Washington, Seattle, Washington 98195, USA. flb@stat.washington.edu
Connor
Paul D
PD
Huggins
Janet E
JE
Barr
Helen M
HM
Pimentel
Kristi D
KD
Streissguth
Ann P
AP
D000328:Adult; D000375:Aging / Q000502:physiology; D000428:Alcohol Drinking / Q000523:psychology; D001724:Birth Weight; D003337:Corpus Callosum / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D063647:Fetal Alcohol Spectrum Disorders / Q000000981:diagnostic imaging / Q000473:pathology*; D005865:Gestational Age; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D007231:Infant, Newborn; D011247:Pregnancy; D012727:Sex Characteristics; D019966:Substance-Related Disorders / Q000150:complications; D011795:Surveys and Questionnaires; D014463:Ultrasonography