First MR imaging with 3T SWI of a 41-year-old male who traveled to high altitude from sea level within 1 day. Patient developed typical symptoms of HACE (headache, fatigue, confusion, ataxia) at 9745 feet (2970 meters). There are diffuse microbleeds with a "black pepper-like" appearance with a predilection for white matter tracts, including the middle cerebellar peduncles (A) and corpus callosum (B), and subcortical white matter (C).
