Serial cranial US for detection of cerebral sinovenous thrombosis in preterm infants.

PURPOSE

To report the incidence of cerebral sinovenous thrombosis (CSVT) in a prospective cohort of preterm infants with a gestational age of less than 29 weeks.

MATERIALS AND METHODS

The local medical ethics review board approved this study, and written parental consent was obtained. Preterm infants with a gestational age of less than 29 weeks who were admitted to the neonatal intensive care unit were prospectively studied with cranial ultrasonography (US). The scanning protocol included visualization with color Doppler imaging of the superior sagittal sinus and transverse sinuses through the anterior (8.5-MHz probe) and mastoid (13-MHz probe) fontanelles. When feasible, magnetic resonance imaging was performed to confirm cranial US-diagnosed CSVT. The differences between preterm infants with and those without CSVT were analyzed by using Mann-Whitney tests for continuous variables and Fisher exact tests for categorical data.

RESULTS

Cranial US was used to document CSVT in 11 of 249 preterm infants with a gestational age of less than 29 weeks. Transverse sinuses were most frequently affected (in all 11 patients with CSVT). All infants with CSVT were asymptomatic. Postnatal age at diagnosis ranged from 5 to 34 days. The mean gestational age was significantly lower in infants with CSVT (25.9 weeks vs 26.8 weeks, P = .038). Of the risk factors studied, only duration of mechanical ventilation was associated with CSVT; it was significantly longer in the CSVT group.

CONCLUSION

Systematic serial cranial US of infants with a gestational age of less than 29 weeks showed a remarkably high incidence of CSVT of 4.4%. Cranial US including color Doppler imaging with scans obtained through the mastoid fontanelle can depict CSVT at an early stage. Treatment of this possibly important condition needs attention.