Fig. 4.

Scatter plots of the correlations between the number of positive slices and age. There is a significant positive correlation between the number of slices with a positive enhancement and age. The Spearman’s rank correlation coefficient was 0.755 (P < 0.01). Note that the gadolinium based contrast agent (GBCA) leakage from the cortical veins into the surrounding cerebrospinal fluid (CSF) was positive in all elderly patients (37 years and above), but negative in all five younger patients (under 37 years). IV-SD-GBCA, intravenous administration of single dose gadolinium based contrast agent; CSF, cerebrospinal fluid.