A 60 years old man who underwent phacoemulsification surgery one year back has come with the complaint of blurring of vision in that eye for the past one month. The defective vision was gradual in onset and it was not associated with pain, redness or watering. He says following surgery, his vision was clear. The most common cause is

Secondary / after cataract / posterior capsular opacification - Most common post operative complication of cataract surgery - Younger the age faster the occurrence - Slow painless loss of vision following cataract surgery Types 1 . Elshnig's pearls (more common ) 2 . Sommering's ring Treatment is done by ND YAG LASER . wavelength of this laser is 1064 nm