New Devices in Glaucoma

Abstract

Glaucoma remains a leading cause of blindness globally. Minimally invasive treatment techniques are rapidly expanding the availability of therapeutic options for glaucoma. These include devices aimed at enhancing outflow through the subconjunctival space, Schlemm's canal, and suprachoroidal space, sustained-release drug delivery devices, and extraocular devices aiming to reduce glaucomatous progression through other novel means. In this review, we provide an overview of several novel devices either newly available or in development for the medical and surgical management of glaucoma. Further studies are required to determine the long-term efficacy of these devices and how they will integrate into the current landscape of glaucoma management.

Keywords: Delayed-action preparation; Excimer laser trabeculostomy; Glaucoma; Glaucoma drainage implants; MINIject; Minimally invasive glaucoma surgery; Minimally invasive micro sclerostomy; Multi-pressure dial; Visiplate; iDOSE.

Fig. 1

Visiplate aqueous shunt [73]. A Image of the device (balanced on the finger tip) demonstrating its profile. B The material consists of microchannels intended to create multiple outflow pathways while maintaining resistance to prevent hypotony. C Serial optical coherence tomography images of an implant in a human eye. The device remained in position through month 3, extending from the anterior chamber to the subconjunctival space with a shallow bleb overlying the plate

Fig. 2

GORE glaucoma drainage implant (GDI) concept [12]. A Current design of the GORE GDI, with a tube connected to an inflatable reservoir composed of proprietary bilayered GORE ePTFE. B Electron microscopy of a sheet of the bilayered ePTFE. The external facing surface is designed to facilitate tissue ingrowth and is backed by an aqueous permeable cell exclusion layer. C Two sheets of the bilayered material are joined and sealed to form a pocket. Aqueous is shunted into the reservoir via the tube and then percolates through the GORE material into the surrounding tissues

Fig. 3

Minimally invasive micro-sclerostomy (MIMS) procedure [74, 75]. A Mitomycin C and viscoelastic are delivered to the subconjunctival space to the area where aqueous will be shunted via the sclerotomy. B A side port is created, and the the anterior chamber is filled with viscoelastic. C The MIMS surgical device is inserted ab interno and advanced above the iris plane towards the angle. D, E The MIMS footpedal is used to create the drainage channel, and a cylinder of scleral tissue is removed, F allowing for flow from the aqueous chamber to the subconjunctival space

Fig. 4

Excimer laser trabeculostomy [73]. A A probe applies laser energy directly to the trabecular meshwork using a foot pedal system. B Blood and microbubbles are often seen post-intervention

Fig. 5

iSTAR MINIject [73]. A The device is 5 mm × 1 mm and made of proprietary silicone material. B Final placement of device in the suprachoroidal space (red arrow). Proper placement is achieved when the green ring is at the level of scleral spur

Fig. 6

Iantrek biostent [73]. A The implant is inserted into a cyclodialysis cannula for ab interno delivery. B Once deployed, the biostent reinforces an iatrogenic cyclodialysis cleft, allowing for drainage around and through the porous device into the suprachoroidal space

Fig. 7

iDose implant [73]. A The device is anchored into the scleral tissue behind the trabecular meshwork. B Image of the implant in the anterior chamber angle nasally in a human eye.

Fig. 8

Multi-pressure dial (MPD) [73]. The device consists of airtight goggles attached to a titratable negative pressure pump