Prenatal diagnosis of microcephaly through combined MRI and ultrasonography: Analysis of a case series

Abstract

Introduction: Intrauterine microcephaly is a complex and lifelong condition that poses significant ethical challenges for clinicians and parents. The prognosis of microcephaly is highly variable and depends on the underlying cause and severity. In addition, microcephaly is often associated with various comorbidities, including intellectual disability, developmental delay, and epilepsy. Ultrasonography (US) is currently the most commonly used imaging modality for detecting microcephaly in the second trimester of pregnancy. However, antenatal brain magnetic resonance imaging (MRI) is increasingly being used as a more sensitive tool to identify structural abnormalities that may suggest a specific diagnosis. In this study, we report a case series of microcephaly diagnosed through the combination of MRI and US.

Patient concerns: How to utilize a combination of MRI and US to screen for fetal microcephaly.

Diagnosis: Based on the results of US and MRI examinations, patient 1 was found to have other craniocerebral malformations, patient 2 demonstrated macrogyria, and patient 3 exhibited skull irregularities.

Interventions: The pregnancies of all 3 patients were terminated through the induction of labor by injecting Rivanol into the amniotic cavity.

Outcomes: The 3 patients were discharged after a period of observation.

Conclusion: US is an important tool for diagnosing fetal microcephaly. However, MRI can overcome the limitations of US and detect additional brain structural abnormalities, thereby providing more specific and valuable prenatal diagnostic information. Therefore, combining MRI and US has significant diagnostic value for fetal microcephaly.

Figure 1.

BPD and HC growth chart. The magnitude of BPD and HC measured by ultrasound was plotted using the x-labels. BPD = biparietal diameter, HC = head circumference.

Figure 2.

Prenatal fetal MRI findings. (A) Thinning of the white matter in the temporal and frontal parietal areas of both sides of the brain, as well as patchy shadows under the frontal lobe cortex on both sides. Compared to a normal fetus at 37 wks of gestation, it was determined that the white matter in the brain of the fetus was dysplastic. (B) The brain contour exhibited the “8” character sign, and a curved T2 high signal shadow was observed in the frontal parietal cortex. The width of the posterior horn of the left and right ventricles was approximately 11 and 10.4 cm, respectively, with a transparent compartment cavity present. No obvious widening was observed in the cisterna magna, and the cerebellar vermis was visible. (C) A normal signal. MRI = magnetic resonance imaging.