Epidural Lipomatosis refers to an excess of fat in the spinal canal that may put pressure on the spinal cord or exiting nerve roots. Google yields a ton of good results, including,
http://www.aans.org/education/journa...04/16-4-11.pdf
Regarding your second question, we hear many stories of people recovering without surgery. Moderate stenosis may be completely asymptomatic. Those of us with stenosis may have something pressing on a nerve causing some symptoms.... if it moves 1/2 a mm in one direction, our symptoms can go away. If it moves 1/2 mm in the other direction, our symptoms become severe.
Each case is unique. I'd want to be evaluated by surgeons who have the option to use the latest technology.
Mark