i HAVE NEVER DONE THIS ON THE WRITABLE SIDE OF THE DISC, BUT IT MIGHT WORK, ANYWAY AND NOT DO FURTHER DAMAGE.  I HAVE REMOVED SHARPIE INK OFF OF THE BACK SIDE OF A DSIC WITH A Q-TIP AND 90% RUBBING ALOCHOL OR THE TYPE INTENDED FOR ELECTRONICS.  YOU MIGHT TRY THIS.
                 jEANNE
                
 August 2007