Femtosecond lentotomy: generating gliding planes inside the crystalline lens to regain accommodation ability

Abstract

Based on Helmholtz Theory for accommodation the increasing sclerosis of lens nucleus and cortex is the main cause for the developments of presbyopia. Existing therapies, however, do not reverse the stiffness of the crystalline lens and thus do not regain real accommodation ability. A new approach to restore the flexibility of the lens could be realized by photodisruption using ultrafast laser pulses. This process, known as fs-lentotomy, was used to create micro-incisions which act as gliding planes inside the crystalline lens without opening the eye globe.

Safety evaluation of femtosecond lentotomy on the porcine lens by optical measurement with 50‐femtosecond laser pulses

“…On the other hand, postoperative crystalline lens collagen fibroblasts found in previous research, as well as in our trials, appeared to be burnt at the laser cutting sites as long as 6 months after surgery, although the cataract was always absent . The remaining cutting pattern, when residual bubbles moved to the optical axis, induced dazzle and a halo effect to the postoperative eye, which negatively affected the patients' vision.…”

The Mechanical Properties of Ex Vivo Bovine and Porcine Crystalline Lenses: Age-Related Changes and Location-Dependent Variations

“…Laser-induced incisions, created by femtosecond laser (femtosecond lentotomy), can make the hardened crystalline lens softer thus allowing to focus a near object clearly (Schumacher et al, 2008; Ripken et al, 2008; Lubatschowski et al, 2010). Potentially, the microbubble-based approach could be combined with femtosecond lentotomy to measure the mechanical properties of the crystalline lens in vivo for guidance and better outcome of the surgery.…”

Optical side-effects of fs-laser treatment in refractive surgery investigated by means of a model eye

“…Therefore, a line by line pattern within a rigid CL (CL10 µm ) and crystalline lens (1L10 µm , 3L10 µm ) were tested. Furthermore, we investigated the amount of rainbow glare when the optical axis (d spared = 2 mm) remains untreated (1 spared L10 µm ), as proposed by Lubatschowski et al (d spared = 1 mm) [30]. For lower laser repetition rates (⪅500 kHz), more complex laser patterns may be applied, among which the most common is a spiral pattern [29].…”