Methods and systems are disclosed for creating an aqueous flow pathway in the trabecular meshwork, juxtacanalicular trabecular meshwork and Schlemm's canal of an eye for reducing elevated intraocular pressure. Some embodiments described apparatus and methods useful in photoablation of tissues. In some embodiments, a photoablation apparatus is used to perforate a tissue, forming an aperture into a space behind the tissue. Gases formed during a photoablation process can be used to pressurize the space behind the tissue to enhance patency of the space. In some embodiments the tissue is the trabecular meshwork of the eye and a wall of Schlemm's canal, and the space behind the tissue is a portion of the lumen of Schlemm's canal. In some embodiments, the method is useful in the treatment of glaucoma by improving outflow from the anterior chamber of the eye into Schlemm's canal, reducing intraocular pressure.