Patent ID: 8016845

Claim:
An instrument for cutting tissue guided along a guide wire comprising: a proximal end having a housing; a shaft extending from said housing to a distal end of the instrument, said shaft having at said distal end an opening to outside of said instrument; a guide tube extending from said shaft through said opening of said shaft in which said guide tube comprises an outer tubular surface, two ends, and an opening extending through said guide tube between said ends of said guide tube; a path through at least said opening of said guide tube; a guide wire extendable along at least said path; and means for longitudinally cutting tissue guided along the outer tubular surface of said guide tube through said opening of said shaft, said means comprising a blade extendable and retractable through said opening of said shaft to cut tissue when present outside of said instrument, wherein said longitudinally cutting means further comprises a blade shuttle attached to said blade having a longitudinal channel within which said guide tube is located to linearly guide said blade shuttle travel along the outer surface of said guide tube.