Advances in Cataract Surgery

Majed Alkharashi; Walter J Stark; Yassine J Daoud


Expert Rev Ophthalmol. 2013;8(5):447-456. 

In This Article

Peripheral Corneal Relaxing Incisions

Peripheral corneal relaxing incisions (PCRIs) are called limbal relaxing incisions (LRIs) in older literature, but this term is inaccurate because the limbus is not incised. The incisions reduce corneal astigmatism by flattening the cornea in the steep meridian and steepening the cornea in the flat meridian. PCRIs are useful for treating 1–1.5 D of regular corneal astigmatism when implanting non toric IOLs. Beyond 1.5 D, the risks associated with PCRI use begin to outweigh the potential benefits compared with toric IOLs. To achieve consistent incision depth, PCRIs should be performed at the beginning of surgery before altering the intraocular pressure. Unwanted under corrections may occur if relaxing incisions are made after a globe is penetrated.[59] Also, the axis marking should be placed while the patient is in the upright position to prevent axis misalignment due to cyclorotation of the eye in the supine position. An axis misalignment of LRI of just 5° results in a 17% reduction in effect.[60] Because of risk of corneal perforation or inducing higher order aberrations, PCRIs should be avoided on corneas with ectasia.[58]

PCRIs could be performed by laser during femtosecond laser-assisted cataract surgery with more precision of depth, axis and length. Also, the epithelium could be left intact to be opened postoperatively if needed.