초록 ▼

The invention features improvements in PRK procedures that relate to preventing non-uniform removal of material from the corneal surface. It has been realized that photoablation by-products resulting during the PRK procedure can affect the accuracy and the predictability of the procedure. Under cert

The invention features improvements in PRK procedures that relate to preventing non-uniform removal of material from the corneal surface. It has been realized that photoablation by-products resulting during the PRK procedure can affect the accuracy and the predictability of the procedure. Under certain conditions, the plume of photoablation by-products that have left the corneal surface can non-uniformly redeposit onto the ablation area and thus affect the uniformity of subsequent material removal. The plume of photoablation by-products, in the space above the corneal surface, can also non-uniformly affect the escape of further photoablation products from the surface. In addition to the plume effects, it has been realized that the hydration level of the corneal tissue during the PRK procedure can vary over the ablation area and likewise non-uniformly affect the PRK procedure.

대표청구항 ▼

[ What is claimed is:] [1.]1. A photo-refractive keratectomy system for producing a desired refractive correction in an ablation area in a cornea of a patient's eye comprising:a source of a beam of photoablating radiation capable of ablating the cornea of the patient's eye during a photo-refractive

[ What is claimed is:] [1.]1. A photo-refractive keratectomy system for producing a desired refractive correction in an ablation area in a cornea of a patient's eye comprising:a source of a beam of photoablating radiation capable of ablating the cornea of the patient's eye during a photo-refractive keratectomy procedure; anda humidified gas flow producer, disposed between the source and the ablation area, for removing material from a surface of the ablation area in a manner substantially preventing a plume of ablation products produced by the photoablating radiation from causing non-uniform ablation of the patient's cornea, by producing a plume-altering flow of humidified gas through an orifice as a series of intermittent puffs of the gas and at a velocity sufficient to substantially prevent non-uniform ablation of the patient's cornea, the puffs being delivered to the ablation area at a plurality of times substantially synchronized with an incidence of the photoablating radiation upon the ablation area.