WILMINGTON, Del., Sept 22 -- Bausch & Lomb Inc.'s surgical subsidiary, Bausch & Lomb Surgical Inc., is being sued by VISX, a laser vision correction provider, for alleged violation of a VISX patent for performing laser vision correction.VISX filed papers in Delaware's US District Court claiming that Bausch & Lomb Surgical's Technolas 217 Excimer Laser System is in violation of VISX's 388 patent. The Patent and Trademark Office issued a re-examination certificate for the company's patent earlier this week after VISX amended the patent's five previous claims and added 60 new ones. Bausch & Lomb anticipated the claim, saying it would defend its right to market the Technolas 217 Excimer System.