PERICEREBRAL FLUID COLLECTION - DIFFERENTIATION OF ENLARGED SUBARACHNOID SPACES FROM SUBDURAL COLLECTIONS WITH COLOR DOPPLER US

PURPOSE: To determine if the cerebral cortical vein sign seen on magne tic resonance (MR) images can be used with color Doppler ultrasound (U S) to differentiate enlarged subarachnoid space from subdural collecti on. MATERIALS AND METHODS: Eighteen infants with pericerebral fluid co llection were prospectively examined with color Doppler US and MR imag ing. Patients were classified into two groups: group A, with positive cortical vein sign (visualization of color-coded cortical veins that c ross fluid collections at cerebral convexities); and group B, without the sign. RESULTS: Positive cortical vein sign was seen at US in 12 pa tients (group A): nine with benign enlargement of subarachnoid spaces, two with brain atrophy, and one with meningococcal meningitis. The ve ins were displaced and embedded within the echogenic pia-arachnoid tha t surrounds the brain or were trapped in the subarachnoid spaces betwe en the neomembrane and cortical surface (group B, negative cortical ve in sign) in four patients with meningitis, two victims of child abuse, and one patient with leukemia. Findings from subsequent MR imaging co nfirmed the color Doppler US findings. CONCLUSION: Color Doppler US de piction of the cortical vein sign appears to be as effective as MR ima ging in differentiating enlargement of the subarachnoid fluid space fr om subdural effusion.