COLORADO SPRINGS, Colo., Jan. 15 -- The Spectranetics Corp. has received approval from the Therapeutic Products Programme (TPP) of Health Canada to expand its study of the use of higher laser energy delivered through Spectranetics' Point 9 mm catheters on difficult-to-treat coronary lesions to 100 patients. In the expanded study, coronary arteries with 80 percent or greater blockages and evidence of calcification, lesions that had previously failed balloon angioplasty, or chronic total occlusions traversable by a guidewire will be treated by Luc Bilodeau., of the Montreal Heart Institute, Montreal, Quebec, and David Hilton of the Royal Jubilee Hospital in Victoria, British Columbia. Bilodeau and Hilton recently completed a successful pilot evaluation involving 36 patients that demonstrated increased efficacy of higher excimer parameters -- blockages were crossed 94 percent of the time using higher laser parameters, compared with 72 percent using normal laser parameters. The expanded study will provide additional data to support the successful pilot study results.FIBER