<prompt> Which laser is used in the management of after cataracts?ArgonKryptonNd-YAGExcimer  <response>: Ans. is c ie Nd-YAG Ref: Parson, 19e, p297; Khurana, 3e, p208 Nd: YAG Neodymium-Yttrium-Aluminium-Garnet laser is used for posterior capsulotomy in cases of after cataract. After cataract, secondary cataract or posterior capsule opacification PCO, is the opacity which follows extracapsular extraction of the lens. After ECCE the lens is composed of the remaining capsule and the residual epithelial cells and cortical fibres that were not removed at the time of surgery. These epithelial cells still possess the capacity to proliferate, differentiate and undergo fibrous metaplasia. Accumulation of these cells lead to after cataract. After cataract or PCO can be of three type Fibrosis type. Pearl type Elschnig pearls Soemmerrings ring Fibrosis type the proliferated epithelial cells deposit on the posterior capsule and form multiple layers which leads to frank opacification. Elschnigs pearls at times, the subcapsular cells proliferate and instead of forming lens fibres, develop into large balloon-like cells which sometimes fill the papillary aperture. Soemmerrings ring the proliferated fibres sometimes, form a ring, enclosed between the two layers of the capsule k a Soemmerrings ring. Treatment after cataract if thin, can be cleared centrally by Nd-YAG laser capsulotomy. If thick, especially in children, they may require discission or can be removed by vit. reous cutter. LASERS USED IN OPHTHALMOLOGY LASER CLINICAL APPLICATION Nd: YAG Posterior Capsulotomy, iridotomy, vitreolysis Frequency-doubled Nd: YAG Retinal photocoagulation, cyclophotocoagulation Argon green Trabeculoplasty, iridoplasty, pupillo mydriasis, retinal photocoagulation Diode laser Retinal photocoagulation Krypton red Retinal photocoagulation Excimer Argon fluoride Photorefractive keratectomy PRK Phototherapeutic keratectomy PTK LASIK, LASEK 