Gold Micro-Shunt offers good IOP reduction without bleb

The SOLX Gold Micro-Shunt (GMS, OccuLogix) is a novel approach to treating increased IOP in patients with open-angle glaucoma that does not respond to other therapies and is a good alternative to trabeculectomy, according to Shlomo Melamed, MD, an investigator based in Tel Aviv, Israel.

The GMS device, made of 24-karat medical-grade gold, is implanted within the supraciliary space, allowing for enhanced aqueous flow between the anterior chamber and the suprachoroidal space. The pressure gradient along the uveoscleral pathway is the driving force for flow through the shunt. The device, which measures 5.2 mm in length and is 2.1 mm at the head and 3-mm wide at the tail, received CE Mark approval in October 2005 and an FDA clinical trial is under way in the United States, noted Dr. Melamed, who spoke at the SOLX educational breakfast symposium Saturday morning.

Dr. Melamed described his implantation technique using a scleral approach. First he creates a fornix-based conjunctival flap and dissects the sclera about 2-mm posterior to the limbus. He exposes the ciliary body and then dissects forward into the anterior chamber and backwards into the superciliary space. He carefully inserts the head of the GMS device into the anterior chamber and then inserts the tail of the device into the supraciliary space. He closes with one to two scleral sutures, he said.

"We are very excited about this technology," Dr. Melamed said. "More investigators are joining us. This device is a good alternative to trabeculectomy."

The shunt offers good IOP lowering as shown in a study of patients with the device implanted compared with those receiving the Ahmed valve, Dr. Melamed said. These patients with glaucoma had uncontrolled IOP. The average IOP at 6 months follow-up with either device was about 17 mm Hg and the number of medications that the patients were taking also decreased.

Ike Ahmed, MD, of Toronto, another investigator of the GMS, offered his surgical pearls for implantation and emphasized the need to understand the anatomy of the eye for accurate dissection and device placement.

Modi Goldenfeld, MD, of Tel Aviv, Israel, described the use of the SOLX Titanium:Sapphire 790 Laser (OccuLogix) for Titanium:Sapphire Laser Trabeculoplasty (TLT) compared with argon laser trabeculoplasty (ALT). The 790 Titanium:Sapphire Laser is available in Europe and Canada. The device is still under investigation in the United States.