Klippel-Trenaunay-Weber (KTW) syndrome: the use of in utero magnetic resonance imaging (MRI) in a prospective diagnosis.

The diagnosis of the Klippel-Trenaunay-Weber (KTW) syndrome is rarely made antenatally. We report the use of both ultrasound and in utero magnetic resonance imaging (MRI) in the prenatal diagnosis of this syndrome. This is the first report of the use of prenatal MRI in the diagnosis of this condition. There was concordance in the findings of both modalities, with limb hypertrophy, and multiple haemangiomata - both subcutaneous and internally - demonstrated with ultrasound and MRI. The patient elected to terminate the pregnancy because of associated oligohydramnios and a small fetal chest noted at 20 weeks. The postmortem examination confirmed the antenatal diagnosis.