Comparing Refractive and Visual Outcomes of MIGS and Traditional Surgeries

Comparing Refractive and Visual Outcomes of Minimally Invasive and Traditional Glaucoma Surgeries

The primary goal of this study is to evaluate refractive and visual outcomes in glaucoma patients who will be having either traditional glaucoma surgery or minimally invasive glaucoma surgery, also known as MIGS.

There is an increasing number of surgical options to lower intraocular pressure (IOP) in patients with glaucoma and ocular hypertension performed with or without concurrent cataract surgery. Today, patients undergoing glaucoma surgery have increasingly higher expectations for their postoperative visual outcomes. Therefore, it is important to understand the influence of various glaucoma surgical procedures on refractive outcomes. This information would aid in patient and surgical procedure selection, pre-operative counseling to set appropriate expectations and may help surgeons adjust their plans and techniques to improve visual outcomes.

The advent of minimally invasive glaucoma surgery (MIGS) procedures further highlights the importance of studying refractive outcomes as many of these surgeries are being performed earlier in the glaucoma severity spectrum where central visual potential is still preserved. Furthermore, this class of surgeries is often performed in combination with cataract surgery.

There remains a lack of data regarding refractive outcomes in patients who have had phaco-iStent, phaco-Cypass, as well as goniotomy (Kahook dual blade (KDB) gonioscopy assisted transluminal trabeculotomy), and Xen gel stent implantation with or without cataract surgery. This information would help during pre-operative patient discussions and lens selection in the context of a combined procedure.

Inclusion Criteria:

Diagnosis of glaucoma or ocular hypertension in the study eye(s) and are consented to receive any of the following procedures:

• Ab interno goniotomy surgery: Gonioscopy-assisted transluminal trabeculotomy (GATT) surgery to decrease intraocular pressure.
• Gelatin stent surgery: Subconjunctival stent (Xen) surgery to decrease intraocular pressure.
• Suprachoroidal stent and cataract surgery: Suprachoroidal stent (Cypass) to decrease intraocular pressure in combination with cataract surgery.
• Trabeculectomy surgery: Glaucoma filtering surgery to decrease intraocular pressure.
• Cataract surgery: Cataract surgery with no glaucoma procedure.

Exclusion Criteria:

Patients with previous corneal ectasia or history of refractive procedures; patients who cannot fixate well due to poor vision (worse than 20/200)