<prompt> The central nebular corneal opacity is easily treated with -.Phototherapeutic keratectomyPenetrating keratoplastyGas permeable contact lensSoft contact lens  <response>: Nebular corneal opacity. It is a faint opacitywhich results due to superficial scars involvingBowmans layer and superficial stroma . A thin, diffuse nebula covering thepupillary area interferes more with vision than thelocalised leucoma away from pupillary area.Fuher, the nebula produces more discomfo topatient due to blurred image owing to irregularastigmatism than the leucoma which completelycuts off the light rays. Phototherapeutic keratectomy PTK performedwith excimer laser is useful in superficial nebularcorneal opacities. REF:Comprehensive ophthalmology,AK Khurana,4th edition,pg no.122. 