Spontaneous

I have a serious and very rare medical condition.  Best guesses suggest that it afflicts about 50 out of 1 million people.  It's called Spontaneous Intracranial Hypotension.  I'm leaking cerebral spinal fluid which decreases the pressure surrounding my brain and causes severe head and neck pain when I'm upright.  When I lay down the pain goes away. As a result I've spent the majority of the past 2 months laying down.  

Most often, a CSF (cerebral spinal fluid) leak is caused by a lumbar puncture or an epidural.  In those cases the doctor knows the cause and the exact location of the leak.
Sometimes a CSF leak is caused by traumatic injury. This is a more complicated problem. While the cause is known, doctors still don't know the exact location of the leak, or how big it is.

A spontaneous leak however, has no known cause and is frequently misdiagnosed. It is commonly believed among medical professionals that the dura, the membrane surrounding the spinal cord, is so robust that only major injury or medical puncture could create a hole.  Prior to my diagnosis I had 4 doctors tell me that a spontaneous leak was virtually impossible.  According to current statistics, spontaneous CSF leaks are diagnosed correctly in the ER 0% of the time.