An elderly woman was moderately injured Monday after she fell asleep and crashed into a fence in Excelsior Springs.  The accident occurred at about 4:00 p.m. on Highway 69, less than a mile north of Vickie Drive.  The Highway Patrol reports Mary Johnson, 76, of Excelsior Springs, was northbound on Hwy 69 when she over corrected, struck a ditch, and became airborne.  She was transported to Excelsior Springs Hospital.