Abstract

Dural sinus thrombosis (DST) is a rare fetal cerebral abnormality. We present 6 cases of DST detected prenatally with ultrasound and magnetic resonance imaging (MRI). In 4 cases, the DST spontaneously resolved with good longterm neonatal outcome. Two patients chose to terminate their pregnancies.

The women presented with ultrasound findings of posterior fossa abnormalities or cysts between 20 and 27 weeks gestation. On MRI, the DST was seen as a lesion of low signal intensity with a centrally placed higher signal lesion consistent with a thrombus. The lesion was often continuous with the saggital sinus and transverse sinus with displacement of the cerebellum and occipital horns of the cerebral hemispheres. The remaining brain appeared normal. In all cases, MRI captured the spontaneous resolution.

There is a lack of information on longterm prognosis because of the small numbers of cases reported. In many cases, parents opt for termination of pregnancy because of the uncertainty about the longterm prognosis.

In conclusion, from our case series and review of the literature, it appears that spontaneous resolution of DST in the antenatal period may suggest a good long term neonatal prognosis. Where the thrombus remains extensive, prognosis should be guarded. MRI is useful for delineating resolution or regression of the thrombus. MRI can be an essential adjunct to ultrasound in the diagnosis and management of DST.