Objective: To determine the value of prenatal MRI in the third trimester in the foetus with intracranial lesions established by ultrasonography.
Design: Descriptive.
Method: During a period of one year, prenatal MRI was performed in 12 patients after ultrasonography had revealed intracranial lesions in the foetus. Postnatally, ultrasonography, MRI or postmortem examination of the brain was performed in 11 children. The MRI examination was carried out in a 1.5 Tesla field. Rapid, T2-weighted images were obtained. To immobilize the child, the pregnant women were sedated.
Results: In 5 cases, prenatal ultrasonography and prenatal MRI resulted in the same diagnosis. In seven cases, MRI provided more information. Postnatal examination confirmed the prenatal diagnosis in 10 of the 11 cases. In one case, maceration rendered supplementary examination impossible.
Conclusion: MRI may be regarded as a valuable alternative diagnostic aid if prenatal ultrasonography is incomplete or the findings are uncertain or limited.