Post-mortem confirmation of fetal brain abnormalities: challenges highlighted by the MERIDIAN cohort study.

OBJECTIVES

To assess and analyse the concordance between post-mortem findings and in utero magnetic resonance imaging (iuMRI) in the MERIDIAN (MRI to enhance the diagnosis of fetal developmental brain abnormalities in utero) cohort.

DESIGN

Prospective cohort study.

SETTING

Fetal medicine units in the UK.

POPULATION

Pregnant women with a diagnosis of fetal brain abnormality identified on ultrasound at 18 weeks of gestation or later.

METHODS

All pregnancies from the MERIDIAN study that resulted in a abortion were included and the rate of uptake and success of post-mortem examinations were calculated. In the cases in which diagnostic information about the fetal brain was obtained by post-mortem, the results were compared with the diagnoses from iuMRI.

MAIN OUTCOME MEASURE

Outcome reference diagnosis from post-mortem examination.

RESULTS

A total of 155 from 823 pregnancies (19%) ended in a termination of pregnancy and 71 (46%) had post-mortem brain examinations, 62 of which were diagnostically adequate. Hence, the overall rate of successful post-mortem investigation was 40%, and for those cases there was a concordance rate of 84% between iuMRI and post-mortem examination. Detailed information is provided when the results of the post-mortem examination and the iuMRI study differed.

CONCLUSIONS

We have shown tissue-validation of radiological diagnosis is hampered by a low rate of post-mortem studies in fetuses aborted with brain abnormalities, a situation further compounded by a 12% rate of autopsy being technically unsuccessful. The agreement between iuMRI and post-mortem findings is high, but our analysis of the discrepant cases provides valuable clues for improving how we provide information for parents. TWEETABLE ABSTRACT: iuMRI should be considered a reliable indicator of fetal brain abnormalities when post-mortem is not performed.