Photodisruptive lasers working at non absorbing wavelengths can be delivered through the ocular medium and focused to a surgical target to produce optical breakdown. When multiple pulses are used, non-invasive surgical procedures, such as posterior capsulotomy, can be performed. The clinical use of photodisruptive lasers is limited however, due to the large volumes of tissue affected by pulses from commercially available Nd:YAG lasers, which operate in the nanosecond pulse duration range. Photodisruptive lasers with pulse durations in the sub-picosecond or femtosecond range have much lower energy thresholds and secondary shock waves, leading to more localized surgical effects. Due to their limited collateral tissue damage, ultrafast lasers can be used to perform high precision noninvasive intraocular applications, such as corneal and glaucoma surgery.
Ron M. Kurtz,
"Ophthalmic applications of ultrafast lasers", Proc. SPIE 3269, Commercial Applications of Ultrafast Lasers, (8 July 1998); doi: 10.1117/12.312333; https://doi.org/10.1117/12.312333