Photodisruption is a form of

minimally invasive surgery Minimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition ...

used in

ophthalmology Ophthalmology (, ) is the branch of medicine that deals with the diagnosis, treatment, and surgery of eye diseases and disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a ...

, utilizing infrared Nd:YAG lasers to form plasma ("lightning bolt"), which then causes acoustic shock waves ("thunderclap") which then in turn affects tissue. The tissue ruptures as a result of the vapor bubble produced by the laser; the temperature required to produce this effect is between 100 and 305 °C. Because the infrared laser is invisible to the surgeon's eye, typically a companion HeNe laser is used in conjunction. However, the eye lens acts as a prism, so the infrared light bends at a shallower angle than the red light, causing

chromatic aberration In optics, chromatic aberration (CA), also called chromatic distortion, color aberration, color fringing, or purple fringing, is a failure of a lens to focus all colors to the same point. It is caused by dispersion: the refractive index of the ...

. This means the area highlighted by the HeNe laser is not precisely the area being affected Nd:YAG laser, and therefore some surgical lasers have an added adjustment to compensate. The first successful use of photodisruption was in 1972, on a case of trabecular meshwork. Photodisruption came to wide use in the early 1980s for the treatment of extracapsular cataract extraction. The technique is most commonly used for

lithotripsy Lithotripsy is a procedure involving the physical destruction of hardened masses like kidney stones, bezoars or gallstones, which may be done non-invasively. The term is derived from the Greek words meaning "breaking (or pulverizing) stones" ( lit ...

urinary calculi Kidney stone disease (known as nephrolithiasis, renal calculus disease, or urolithiasis) is a crystallopathy and occurs when there are too many minerals in the urine and not enough liquid or hydration. This imbalance causes tiny pieces of cry ...

and the treatment of posterior

capsulotomy Capsulotomy (BrE /kæpsjuː'lɒtəmi/, AmE /kæpsuː'lɑːtəmi/) is a type of eye surgery in which an incision is made into the capsule of the crystalline lens of the eye. In modern cataract operations, the lens capsule is usually not removed. ...

of the lens. When used in corneal surgery, picosecond and nanosecond disruptors are used on the lamellae of the corneal stroma, and the method may be preferable as it leaves the

epithelium Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of man ...

and

Bowman's layer The Bowman's layer (Bowman's membrane, anterior limiting lamina, anterior elastic lamina) is a smooth, acellular, nonregenerating layer, located between the superficial epithelium and the stroma in the cornea of the eye. It is composed of strong, ...

unharmed. This modifies the outer corneal curvature, which affects the refractive property of the eye.

References

{{Eye procedures Eye surgery