Piano Man' hitmaker Billy Joel was recently diagnosed with a brain disorder called NPH or Normal Pressure Hydrocephalus, which led him to cancel his upcoming concerts. But what is NPH? Read on and find out.

Rock legend Billy Joel, aged 76, has been diagnosed with normal pressure hydrocephalus (NPH), a neurological condition that has forced him to cancel his upcoming tour.

N.P.H. occurs when excess cerebrospinal fluid accumulates in the brain, causing difficulty walking, trouble controlling one’s bladder and memory problems.