Patent ID: 7651469

Claim:
A marked wire guide apparatus for insertion into a patient comprising: a mandrel having a coating disposed on at least one segment thereof, the coating having a low coefficient of friction and being comprised of at least one of polymeric and hydrophilic material, wherein the coating is at least partially removed from portions of the at least one segment; a plurality of distinct non-removed coating areas disposed on the at least one segment of the mandrel, the plurality of distinct non-removed coating areas comprising the coating and having a first thickness; and a plurality of distinct removed coating areas located on the at least one segment of the mandrel at about every 5 cm to 20 cm, the plurality of distinct removed coating areas having a second thickness less than the first thickness and defining depth marks indicated by the coating at least partially removed from the mandrel with said depth marks being configured to determine the length of the mandrel inserted into a patient; and a catheter for advancement over the mandrel having a length based upon the determined length of the mandrel.