Aqueous humor outflow imaging and minimally invasive glaucoma surgeries

Minimally invasive glaucoma surgeries (MIGSs) have exploded in the last 15 years as a glaucoma treatment option. MIGS are safe and effective although greater intraocular pressure reduction is desired. Aqueous humor outflow (AHO) imaging is being developed as a way to better understand outflow biology, pathophysiological ocular hypertension, and as way to improve MIGS. Many methods have been developed, including structural imaging, canalography/channelography, episcleral venous fluid wave, hemoglobin video imaging, and aqueous angiography. None are yet perfect. This chapter outlines the key characteristics for an ideal AHO imaging method that can be used to improve MIGS. Current methods are assessed along these criteria to highlight individual advantages and disadvantages of each technique. Ultimately, with better AHO imaging, improved MIGS or MIGS techniques can be envisioned. Better AHO imaging techniques may also lead to the discovery of improved pharmacological glaucoma treatment options as well.