Twin Pregnancy Complicated by Subdural Hematoma: A Case Report

Introduction: Subdural hematoma (SDH) is caused by venous bleeding between the dura and arachnoid matter in the subdural space. Limited data exists on the incidence and prevalence of SDH due to the failure to diagnose this condition during mid-trimester ultrasounds. Etiology of intrauterine SDH is unknown in many cases. Ultrasonography, along with confirmatory magnetic resonance imaging allows for higher diagnostic accuracy. We present a case of monochorionic diamniotic twins with abnormal neuroanatomy consistent with SDH.

Case Report: A 25-year-old G3P1 presented for an anatomical survey @ 18^5/7 weeks. Prenatal care was complicated by frequent admissions for hyperemesis gravidarum, and an abnormal maternal Quad screen for borderline ONTD. All other prenatal laboratory findings were normal. Sonographic findings noted a monochorionic diamniotic twin pregnancy. Twin B was noted to have massive ventriculomegaly. Patient was referred for a higher level of care for management. Upon transfer, @ 20^5/7 weeks, repeat ultrasound, MRI and genetic amniocentesis was undertaken; karyotypic analysis revealed two genetically normal males. MRI revealed: “Twin A—large bilateral supratentorial/infratentorial subdural hematoma causing enlarged biparietal diameter/suspected hypertelorism; Twin B—severe ventriculomegaly with enlargement of the BPD. There is abnormal heterogeneity of the posterior fossa structures c/w subdural hematoma in the region with suspicion for cerebellar hypoplasia and hemorrhage. The patient underwent extensive counseling and opted for termination of pregnancy. She delivered both twins breech vaginally. She declined autopsy.

Discussion: Fetal intracranial hemorrhage is a complication associated with significant fetal mortality and morbidity. Fetal subdural hematoma is a type of intracranial hemorrhage where blood collects between the dura and arachnoid matter and is extremely rare. While the underlying cause of SDH is often unidentified, maternal injury, maternal use of anticoagulants, maternal and or fetal autoimmune thrombocytopenia and maternal Vitamin K deficiency caused by hyperemesis gravidarum, are among the more common causes.

Currently, ultrasound is the initial and principal screening imaging modality for detection and diagnosis of intrauterine subdural hematoma. MRI is additionally utilized to aid in more detailed imaging of cerebral architecture, showing more distinct boundaries between tissues of different echodensities compared with that obtained from ultrasound.

Upon diagnosis of fetal SDH, thorough counseling on the possible fetal and neonatal outcomes should be provided to the parents. As the data remains limited, along with the high likelihood of a poor prognosis, open discussion concerning termination is warranted.

Fig. 1 MRI (20 weeks 4 days). Twin A, bilateral Ventriculomegaly with infratentorial subdural hematoma measuring up to 17 -mm in thickness, causing enlarged head size.

Fig. 2 MRI (20 weeks 4 days). Twin B, bilateral severe ventriculomegaly, measuring approximately 22-23 mm in diameter. There is enlargement of biparietal diameters. There is partial defect in the septum pellucidum. There is abnormal heterogeneity of the posterior fossa structures with suggestion of cerebellar injury/hemorrhage.

Publication History

Article published online:
17 September 2021