Abstract
Background: Foetal thrombosis of the torcular herophili is a rare entity, usually detected during the 2nd
trimester. Prognosis and risk factors for severe outcome are yet poorly characterized, but important for
counselling and management.
Aim: To describe two new cases of foetal thrombosis of the torcular herophili and review the literature,
focusing on prognosis and predictive factors.
Methods and Results: We retrospectively reviewed clinical data, antenatal and postnatal MRI findings
of two cases of foetal torcular herophili thrombosis diagnosed prenatally. Foetal MRI was performed at
36 and 32 weeks’ GA, after abnormal ultrasounds at 32 and 31+5 weeks’ GA, respectively. Last clinical
and MRI postnatal follow-up was performed at 5 years and 15 months, respectively. Both patients had
ischaemic brain lesions and neurological impairment. We found 66 cases reported in the literature. The
overall mortality rate was 15% while a favorable outcome was seen in 87% of surviving patients. Risk
factors for neurological disability were male sex and ischemic brain lesions, while dural arteriovenous
shunt or signs of foetal decompensation were associated with foetal demise or post-natal death.
Conclusion: Posterior fossa foetal ultrasound allow suspicion of foetal dural sinus thrombosis, which is
confirmed by foetal MRI. Outcome ranges from foetal demise to complete spontaneous regression with
normal development. Identified foetal neurological risk factors will help the management of this rare and
potentially life threatening conditio