12/4/2015 I have the following financial interests and relationships to disclose: MIGS: Alcon Laboratories S Maybe Its Glaucoma Surgery! Allergan C,S New World Medical S NIH-NEI S Joseph Caprioli RPB S Simms-Mann Foundation S Transcend C Other Philanthropic Support S Why MIGS? • Compliance with meds huge problem • Complications of surgery are considerable • Search for bleb-less approaches – Blebitis – Endophthalmitis Ophthalmology 2015 1
12/4/2015 Opinionated Facts MIGS • Trabeculectomy is effective, with • Evolving approaches and devices acceptable risk-benefit ratio in patients at • Current definition is fuzzy risk for visual loss • A group of alternative glaucoma surgeries intended to cause less tissue disruption and fewer – But you have to do it correctly! complications than traditional procedures – Real surgery for real glaucoma • It should be a bona fide glaucoma operation, not a – Better than tubes for first surgery, especially cataract surgery add-on (to bill for) for low target IOPs See Editorial on TVT Study, AJO May 2011 Minimally Invasive Glaucoma Surgery - Definition Met: Implantable Devices • Intended to lower IOP via outflow • Ab-interno or ab-externo approach • Limited scleral dissection Sustained release Anterior chamber injection Dissolvable polymer – needle or device penetration of sclera OK Definition Not Met: – procedures with significant scleral dissection excluded • Minimal conjunctival manipulation – limited peritomy or small incision OK 2
12/4/2015 MIGS Effectiveness: What Locations To Which Aqueous Can We Expect? is Directed by MIGS Device • IOP reduction based on anatomy and • Influence efficacy and safety of physiology of aqueous outflow pathway new devices • Schlemm’s canal is not continuous; flow –Schlemm’s canal into the collector channels and veins is –Suprachoroidal Space segmental –Sub-conjunctival Space MIGS Effectiveness: What Can We Expect? • Flow in aqueous veins is pulsatile • There is almost no circumferential flow within Schlemm’s canal • If entire TM is opened, outflow resistance is reduced by 75% (Grant) 3
12/4/2015 Safety and Efficacy Considerations Minimally Invasive Glaucoma Surgery • Safety and efficacy are linked, LION • While all procedures should have • Ultimately the “MIGS” classification measurable efficacy… should be earned, based on: – Safer procedures may have modest efficacy • at least some efficacy – Procedures with greater risk should have • an enhanced safety profile as determined greater efficacy by appropriately controlled clinical trials My Opinion • Goal of safe, minimally invasive surgery with measurable efficacy to treat real glaucoma has not been attained • Efforts to reinvent the wheel have failed • Some promising areas – Ab-interno suprachoroidal shunts – Injection of sustained release drugs • We are not not there yet, but need to keep trying 4
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