Background and purpose: Fetal SAH is an intracranial malformation. The typical diagnostic features of fetal SAH in ultrasound have not been reported. This study aimed to evaluate the diagnostic value of Sylvian fissure hyperechogenicity by prenatal ultrasound in fetuses with SAH.
Materials and methods: The features on ultrasound and MR imaging of 10 fetuses with SAH were reviewed and summarized. The diagnostic value of the Sylvian fissure in fetal SAH by prenatal ultrasound was evaluated.
Results: The typical and most obvious manifestations of SAH during the prenatal period were hyperechogenicity in the subarachnoid cavity, especially in the Sylvian fissure; all 10 cases (10/10) had such manifestations. Other manifestations included a hyperecho in other sulci (6/10), especially in the subfrontal sulcus, superior temporal sulcus, or parieto-occipital sulcus; a hyperecho in the cisterns (8/10), especially in the suprasellar cistern, posterior cranial fossa, cisterna ambiens, or quadrigeminal cistern; and a hyperecho around the anterior and posterior longitudinal fissures (2/10). Combined hemorrhage in the parenchymal layer or ventricles (9/10) was found. In addition, Doppler ultrasound showed that the peak flow velocity in the MCA increased in 6 cases (6/10).
Conclusions: The homogeneous hyperechogenicity of the Sylvian fissure is an important clue for detecting and diagnosing fetal SAH by prenatal ultrasound. A diagnostic approach has been proposed for fetal SAH, which has great significance in further prognosis.
© 2022 by American Journal of Neuroradiology.