Glaucoma management: SLT on trial

September 10, 2007

The use of selective laser trabeculoplasty (SLT) in the management of glaucoma is a safe and effective treatment method, according to Shlomo Melamed from the Sam Rothbery Glaucoma Centre in Tel Aviv, Israel, speaking at the Ellex symposium.

The use of selective laser trabeculoplasty (SLT) in the management of glaucoma is a safe and effective treatment method, according to Shlomo Melamed from the Sam Rothbery Glaucoma Centre in Tel Aviv, Israel, speaking at the Ellex symposium.

Lasers have a long history of use in the management of glaucoma, and the Glaucoma Laser Trial (GLT) established the efficacy of argon laser trabeculoplasty (ALT) in lowering intraocular pressure (IOP) in primary open-angle glaucoma (POAG) patients. However, many studies have shown that there are risks involved with this procedure: post-treatment increase in IOP, limited efficacy, coagulative damage and scarring to the trabecular meshwork (TM), and it may also limit the efficacy of further non-surgical therapy. As a result, SLT has been developed as an alternative to ALT, as it does not cause structural or coagulative damage to the TM.

ALT has also been shown to induce positive biological effects on the TM, such as increased phagocytic activity, trabeculitis and shift of aqueous flow. "However, you do not need an 'over-kill' of ALT to achieve this, " said Melamed. "A more gentle treatment of pigmented cells will do this just as well. " In various studies, it has been shown that SLT can increase aqueous outflow and cell permeability (Alvarado, 2007), and 90º treatment is just as effective as 180º (Chen et al., 2004). In a five-year follow-up study of Chinese patients, SLT has demonstrated equal success to medical treatment (Lai et al., 2004), while another study revealed that SLT is as effective as ALT, but causes less inflammation and is better tolerated by patients (Martinez de la Casa et al., 2004). It has also been shown that SLT can be used more than twice (Nagar et al., 2007).

"SLT the safest procedure in glaucoma management, " Melamed said. "It does not produce any side effects and it is not expensive because it eliminates the cost of chronic drug use. "

In a recent study evaluating the use of SLT as a primary treatment for POAG, Melamed found a 30% IOP reduction in a two-year follow-up. "Interestingly, we also found an IOP reduction of over 5 mmHg within one hour in 33% of the eyes tested, " he added.

"As a result of these studies, we believe that SLT is an effective and very safe treatment method for glaucoma, " he concluded. "SLT should therefore be offered as an initial treatment choice in certain POAG, ocular hypertension and pseudoexfoliative glaucoma patients. "