Ab interno Schlemm's Canal Surgery.

Area of Science:

• Ophthalmology
• Glaucoma Surgery
• Intraocular Pressure Management

Background:

• Primary open-angle glaucoma involves resistance to aqueous outflow at the trabecular meshwork (TM) and inner wall of Schlemm's canal.
• Augmenting the conventional outflow pathway can lower intraocular pressure (IOP).
• Internal filtration surgeries represent a novel approach to enhance conventional outflow.

Purpose of the Study:

• To review novel surgical approaches for enhancing the conventional outflow pathway in open-angle glaucoma.
• To categorize and describe ab interno Schlemm's canal surgical techniques.
• To highlight the safety and efficacy of these internal filtration procedures.

Main Methods:

• Categorization of four novel ab interno Schlemm's canal surgical approaches.
• Description of specific surgical devices and techniques within each category.
• Review of published results on safety and efficacy.

Main Results:

• Ab interno Schlemm's canal surgery encompasses trabecular meshwork removal, microstent implantation, TM disruption, and canal dilation.
• Specific procedures include ab interno trabeculectomy, microstent bypass, ab interno trabeculotomy, and ab interno canaloplasty.
• Published data indicate these internal filtration surgeries are safe and effective for open-angle glaucoma.

Conclusions:

• Ab interno Schlemm's canal surgeries offer a minimally invasive, internal approach to treating open-angle glaucoma.
• These procedures enhance physiologic outflow by targeting the conventional pathway.
• Current evidence supports the safety and efficacy of these novel surgical options.