Arterial spin labeling perfusion is becoming an important clinical tool. We find it particularly useful in children in whom it is difficult to obtain contrast enhanced MR perfusion due to the smaller size of needles used. Here is a case of a balloon cell type cortical dysplasia in the right temporoparietal region 
with low cerebral blood flow on the ASL study. I think that our Blogsite is the ideal place to share these cases with the rest of the Neuroradiology community. Similar findings to the ones shown here were reported in the following article found in the publication preview section of www.ajnr.org:
Pollock J, Whitlow C, Tan H, et al. Pulsed Arterial Spin-Labeled MR Imaging Evaluation of Tuberous Sclerosis. AJNR Am J Neuroradiol. 10.3174/ajnr.A1428
