<unk>  is a procedure that involves correcting or addressing any issues that have arisen from a previous<unk>  surgery. The surgery is more difficult to perform and is more complicated than an initial<unk>  surgery, since the site of the procedure has been operated on before. The reasons for<unk>  surgeries include contour abnormalities, asymmetry and unusually high<unk>  height. The procedure is known to have more complications and issues than initial<unk>  surgeries due to the presence of excess scar tissue at the surgery site.
Eyelid revision
Ocular prosthesis
Pyeloplasty
Fundal massage
Scleral reinforcement surgery
Corrective lens
Boston keratoprosthesis
Endoscopic ear surgery