Volume of intracranial structures on three-dimensional ultrasound in fetuses with congenital heart disease

Objective: To investigate the volume of intracranial structures in fetuses with congenital heart disease (CHD).

Methods: Total intracranial volume, frontal lobes volume, thalamus volume and cerebellar volume were prospectively evaluated and compared in 73 fetuses with CHD and 168 normal fetuses using three-dimensional ultrasound combined with post-processing software at 20 + 0 to 36 + 6 weeks of gestation. Multiple regression analyses were performed to identify risk factors for reduced volume of intracranial structures.

Results: From the 28th week of gestation onwards, total brain volumes and those of specific structures became progressively smaller in fetuses with CHD relative to those in controls (P < 0.05). The decrease was largest in frontal lobes volume, followed by total intracranial volume and cerebellar volume, and the smallest decrease was in thalamus volume (P < 0.05). Multivariable analysis showed that the diagnostic category (P < 0.001) was independently associated with smaller brain volumes in fetuses with CHD. The largest differences from controls occurred in hypoplastic left heart syndrome (HLHS), followed by aortic hypoplasia, transposition of the great arteries (TGA) and tetralogy of Fallot (TOF).

Conclusions: The volume of intracranial structures is smaller in fetuses with CHD, particularly in those with HLHS, aortic hypoplasia or TGA. This study highlights the need for routine brain screening and early intervention to improve neurodevelopmental outcomes in fetuses with CHD.