A medical system includes a tube (102) configured to pass internally into a body and an index (108) disposed on the tube and configured to be visible internally within the tube. An outermost nested cannula (110) component is affixed within the tube with a geometric relationship with the tube as indicated by the index. An imaging device (106) is configured to image an anatomic reference relative to the index such that alignment of the outermost nested cannula component is provided by aligning the at least one index with the anatomic reference.