Corneal Welding Using Hydrogen Fluoride Lasers

Tissue adhesives in ocular surgery

“…Its peak optical absorption is at wavelength 800-810 nm [185], at which the corneal stroma is transparent, and the extensive documentation of its toxicity makes ICG a popular chromophore for tissue laser welding. The chromophore allows selective optical absorption of laser radiation, which enhances photothermal activation of the stromal collagen so that much lower laser power is required than that of direct tissue irradiation without chromophores.…”

“…At NIR, absorption by tissue is minimal and chromophores applied on wound site allow selective and more controllable welding. Ideally, laser irradiation should be confined as it can cause collagen shrinkage, denaturation, photocoagulation and tissue necrosis [185,186].…”

Microscopic characterization of collagen modifications induced by low‐temperature diode‐laser welding of corneal tissue

“…In ophthalmology, experimental studies of laser-induced suturing of corneal tissue on animal models have been reported since 1992 by various authors [23,[25][26][27]. Major potentialities in using lasers for the welding of corneal tissue are a reduction of post-operative astigmatism, surgical time, and foreign body reaction, when used in lieu of conventional suturing.…”

“…Major potentialities in using lasers for the welding of corneal tissue are a reduction of post-operative astigmatism, surgical time, and foreign body reaction, when used in lieu of conventional suturing. Most of the laser welding procedures that have been proposed up to now were based on the use of water as an endogenous chromophore for absorbing near-and far-infrared laser light [25,26,28,29]. However, they did not demonstrate it to be safe enough to reach the clinical phase, since the achievement of successful welding of corneal cuts was frequently accompanied by heat side effects which caused partial stromal coagulation and affected corneal transparency.…”

NIR laser tissue welding of in vitro porcine cornea and sclera tissue

“…Eaton et al used a diode laser (808 nm) in combination with a tissue glue mixture to close scleral tunnels [17]. Burstein et al describe the first successful fusion of corneal tissue from porcine cadaver eyes using a fundamental hydrogen fluoride (HF) wavelength of 2,560 nm at 30 mW and a HF overtone wavelength of 1,340 nm at 320 mW produced from a HF chemical laser [40]. The latter wavelength produced a deeper weld (300 mm) and stronger corneal weld.…”