Dandy-Walker malformation complex: correlation between ultrasonographic diagnosis and postmortem neuropathology.
OBJECTIVE
This autopsy-based study was designed to evaluate sonographic and neuropathologic findings of fetuses diagnosed prenatally with Dandy-Walker malformation complex.


METHODS
The retrospective study encompassed a series of 44 autopsy cases from 2 tertiary referral centers with a prenatal ultrasound diagnosis of Dandy-Walker malformation complex between 1995 and 2003. Ultrasound and pathology data from the cases and from age-matched controls were reviewed in a blinded manner. An unequivocal diagnosis of Dandy-Walker malformation complex from ultrasonography or pathology archival images required significant hypoplasia or aplasia of the cerebellar vermis.


RESULTS
Neuropathologic examination failed to confirm the prenatal diagnosis of Dandy-Walker malformation complex in 59% (26/44, 95% confidence interval [CI] 44-72) of the cases. After standardized reevaluation of high quality archival sonograms and pathology images, concordance remained poor at 55% (6/11 cases, 95% CI 28-79). Sonographic features that favored concordance included marked enlargement of the cisterna magna (> or = 10 mm), complete aplasia of the vermis, and a trapezoid-shaped gap between the cerebellar hemispheres. This latter finding contrasted with a keyhole-shaped gap in fetuses with no cerebellar neuropathology.


CONCLUSIONS
Correlation between a prenatal ultrasound diagnosis of Dandy-Walker malformation complex and autopsy neuropathology findings is poor. Unequivocal prenatal sonographic diagnosis of Dandy-Walker malformation complex should be reserved for cases with the classic findings of Dandy-Walker malformation, including enlargement of the cisterna magna, aplasia of the vermis, and a trapezoid-shaped, rather than keyhole-shaped, interhemispheric gap.


METHODS
III.
Phillips
Joanna J
JJ
Department of Pathology, University of California, San Francisco, California, USA.
Mahony
Barry S
BS
Siebert
Joseph R
JR
Lalani
Tasneem
T
Fligner
Corinne L
CL
Kapur
Raj P
RP
D000293:Adolescent; D000328:Adult; D002490:Central Nervous System / Q000000981:diagnostic imaging / Q000473:pathology; D003616:Dandy-Walker Syndrome / Q000000981:diagnostic imaging* / Q000473:pathology*; D003951:Diagnostic Errors; D005260:Female; D005333:Fetus / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal