Surgical Correction of Presbyopia

Lenticular, Corneal, and Scleral Approaches

Michael Greenwood, MD; Shamik Bafna, MD; Vance Thompson, MD


Int Ophthalmol Clin. 2016;56(3):149-166. 

In This Article

Presbyopic Femtosecond Laser Ablation (Intracor)

The use of femtosecond laser pulses that are applied in a concentric ring inside the corneal stroma is another technique used to induce changes in the corneal shape without cutting a flap. This procedure is called Intracor and was performed and published by Ruiz et al[45] for the first time using a Technolas Femtosecond Laser (Bausch and Lomb Technolas, Munich, Germany). During this procedure the pattern of laser delivery is entirely intrastromal, impacting neither the endothelium, Descemet membrane, Bowman layer, nor epithelium at any point during the operation, creating a central steepening of the anterior corneal surface. Advantages to this procedure include: no epithelial disruption, no pain and inflammation related to the absence of epithelium, and quick recovery. Early results showed a significant and stable gain of UNVA and corneal steepening, without a significant loss of endothelial cells or corneal thinning up to 18 months postoperatively. No significant regression of visual acuity or further corneal steepening occurred during the follow-up period.[46,47] There are also some concerning disadvantages. This procedure can lead to a reduction of mesopic contrast sensitivity and an increase of glare sensitivity.[48] The authors suggested that possible consequences on night driving ability should be discussed with potential patients before treatment. Very recently, a case of keratectasia after intracor combined with Supracor LASIK enhancement was reported in an eye without risk factors for keratectasia.[49]

The above-mentioned disadvantages of the PresbyLASIK and Intracor raise concerns on the mechanical stability of the cornea. These types of procedures are the most worrisome to the authors of this paper and feel that further studies with larger number of eyes are required to assess the safety, efficacy, and long-term stability of these new procedures.