GLAUCOMA SURGERY: FROM THEN TIL NOW (COPE Course ID: GL)

Transcription

1 MIGS: How did we get here? GLAUCOMA SURGERY: FROM THEN TIL NOW (COPE Course ID: GL) John Gelvin, O.D., F.A.A.O. MOYES EYE CENTER Kansas City, Missouri 1. Tube vs Trabeculectomy? (creating a hole through the eye internally to drain aqueous from the AC into the subconjunctival space.) a. Tube Shunt i. Ahmed shunts ii. Barveldt shunts b. Trabeculectomy i. Trabeculectomy With or without MMC ii. Express Mini-shunt with trabeculectomy 1. 2 sizes. P200 and the P50. P200 soon to be discontinued. 2. Trab performed, yet first mini type device created to assist in maintaining open sclerostomy site. Very good for thinner superior conjunctiva. c. TVT Study (Tube vs Trab) after 5 years of follow up. i. Tube shunt had higher success rate. ii. At 5 years, probability of failure was 29.8% in Tube sx. 1. There was a 5% per year in this study. 3.9% at year one, 15.1% at year 3 and 29.8% at year 5. iii.at 5 years, probability of failure was 46.9% in Trab sx. iv. In Trab with MMC, at 1 year failure rate was 13.5%, at 3 years 30.7% and 46.9% in 5 years. v. In Trab with 5 FU (in the FFSS) 16% failed at 1 year, 29% at 3 years and 51% at 5 years.

2 Barveldt- See Video Ahmed- See Video 2. Trabeculectomy alternatives. (why alternatives? Complications related to external drainage include scarring, hypotony, flat AC, Choroidal effusion, bleb leaks, blebitis.) First KNOW YOUR GLAUCOMA STAGING CODES!!! mild, moderate, severe, indeterminate, Unspecified a. Minimally Invasive Glaucoma Surgery (MIGS) Moving into utilization of Schlemm s canal or the suprachoroidal space as an alternative route of aqueous drainage. i. I-Stent (Glaucos) First implanted in USA by R. Cravens st to be approved by FDA. I-Stent is involving going through the TM only. Approved for Mild disease. Average IOP 16mmHg. ii. In the pipeline is i-stent Inject- an injector with 2 preloaded stents. Both stents will be placed through the TM into Schlemm s canal. May see the dual injector early See Video iii.cy-pass Micro-Stent (Alcon) 2 nd approved by FDA. Designed to vent into the supraciliary (or suprachoroidal ) space. We are still NOT getting reimbursed by Humana Both of these are approved for mild to moderate POAG in conjunction with cataract surgery. Similar safety profile to phaco surgery alone. 70% of eyes achieve and maintain an IOP reduction of at least 20%. Those who respond well, 93% are off all glaucoma medications. We are currently seeing IOP of 8-13 mmhg. iv. XEN-gel stent (Allergan) Recently launched. Payments??? 6 mm stent implanted through the trabeculum into the subconjunctival space. Approved for OAG or refractory glaucoma who will be unresponsive to max meds therapy. No adverse reports of tx. ¼ of these patients may require bleb needling in office.

3 Mean IOP pre-op 25 mmhg, mean meds 3.5, VF MD -15. At one year, mean IOP 13.5, mean meds 1.7 (39% were drug free). Will not pay for ACG cases, yet, new studies coming out on productive findings. Found to be very effective in Primary Angle Closure Glaucoma: Post surgically, medication was found to be reduced by 72% at one year compared to baseline. All patients with available data at one year had IOP reduced greater than or equal to 20%. The XEN 45 Gel Stent is composed of a gelatin derived from porcine dermis, formed into a tube, and then cross-linked with glutaraldehyde. The durable gelatin is designed to minimally swell, soften, and become flexible when hydrated. The stent s design also aids in retention of the XEN 45 Gel Stent in its intended location after surgical implantation. The XEN 45 Gel Stent dimensions (approximations) for the dry state are: XEN 45 Gel Stent Dimensions XEN 45 Gel Stent: Length 6 mm Inner Diameter 45 um Outer Diameter 150 um. XEN INJECTOR The XEN Injector is a singleuse mechanical delivery system for the XEN 45 Gel Stent, which is preloaded in the XEN Injector for insertion and delivery into the eye. The XEN Injector allows the surgeon to advance and deliver the XEN 45 Gel Stent to the desired location. INDICATIONS The XEN Glaucoma Treatment System is indicated for the management of severe OAG or refractory glaucomas, including cases where previous surgical treatment has failed, cases of primary open angle glaucoma, and pseudoexfoliative or pigmentary glaucoma with open angles that are unresponsive to maximum tolerated medical therapy. CONTRAINDICATIONS Implantation of the XEN 45 Gel Stent is contraindicated under the following circumstances or conditions: x Angle closure glaucoma where angle has not been surgically opened x Previous glaucoma shunt/valve in the target quadrant x Presence of conjunctival scarring, prior conjunctival surgery or other conjunctival pathologies (e.g., pterygium) in the target quadrant x Active inflammation (e.g., blepharitis, conjunctivitis, keratitis, uveitis) x Active iris neovascularization or neovascularization of the iris within six months of the surgical date x Anterior chamber intraocular lens x Presence of intraocular silicone oil x Vitreous present in the anterior chamber. We are currently seeing IOP in the single digits to the low teens postoperatively. Prefer to see IOP lower early in the first 1-2 weeks. MMC is injected into conj for 20 seconds then moved towards back of conj then removed prior to injecting the Xen implant. See Video

4 (Trabectome: We currently do not have the device. It is approved for mild, moderate or severe OAG glaucoma. It is used to excise or strip the TM itself. Usually is striping 4-6 clock hours of TM. Thus, exposing schlemm s canal. So, is not approved for any form of narrow angle or angle closure glaucoma. b. MIGS future tense i. i-stent(glaucos) is working on istent Supra. This will drain into the suprachoroidal space. May still be 2 years out. ii. Hydrus Microstent (Ivantis) Trial information (n=3,000) will be out by end of the year. It s the only device that dilates and reconstructs Schlemm s canal allowing IOP to get to the episcleral collector channels. In 2015, 80% showed at least 20% drop in diurnal IOP after 2 years. This device is introduced using a metal canula that incises the TM then advances into the canal. This works similarly to the Kahook dual blade. 1. A fascinating next step with this device is to attach a 24 hour IOP monitor to the device. They are using prototypes that report though an Iphone app. iii.the MicroShunt (InnFocus) will be the first MIG for the treatment of mild, moderate, severe POAG that promises sustained IOP below 15 mmhg while eliminating gtts for most patients. Device is made of SIBS (now used in cardiac patients). 1. See Video. c. Kahook Duel Blade (New World Medical) New device for the removal of TM. Its is an ab-interno micro-incisional instrument (not an implant). Could be described as abinterno goniotomy. This blade has a pointed tip that penetrates the TM and a ramp that elevates the tissue under pressure. Two blades free the tissue strip from the rest

5 of the meshwork. It is thought that we will see a 5 mmhg IOP drop when used with cataract surgery. Also, 80% of these patients can eliminate at least one medication. 1. See Video. d. idose (Glaucos) working on deposited travoprost which is injected into the sclera to allow medicine to sink into the AC. Phase II trial now. e. Equinox goggles. Our limiting factor in getting to Mars is papilledema. This must be resolved first. Equinox treats glaucoma disease as a condition of two pressures- IOP and ICP. It is the gradient between these two at the optic nerve that destroys vision. Those with glaucoma have lower ICP than matched controls. Normotensive glaucoma patients have even lower ICP. Ocular hypertensives have higher protective ICP. If ICP is higher with normal IOP, the head of the ONH swells which affects 50% of those on the International Space Station. The goggles can increase exterior pressure on the eye, thus mildly raising the IOP, and hopefully be useful in combating papilledema in space. These goggles worn while sleeping reduce the exterior pressure of the eye, effectively lowering IOP relative to ICP.