The excimer laser was first introduced clinically in 1996 for corneal surface ablation.1 This device enabled precise tissue removal and, as a “cool” laser, prevented thermal damage to surrounding tissues. Ultimately, interest expanded to glaucoma, and an excimer laser application was developed for full-thickness sclerostomy. Next, the focus shifted to the TM, and the trabeculostomy technique emerged.2
When excimer lasers were first used to treat glaucoma, phacoemulsification was in its early stages. ALT and SLT were gaining popularity, but the industry was focused on new glaucoma medications, especially prostaglandin analogues. Since the advent of MIGS, a dramatic increase in procedural interventions has occurred, and interest in laser technology has grown. Advances in the ELIOS excimer laser system and probe have led to a more sophisticated, user-friendly approach.
ELIOS: Technical Aspects and Potential Benefits
The ELIOS laser emits energy through an intraocular fiberoptic probe to create microchannels through the TM up to the inner wall of SC with high precision. The ab interno, nonthermal approach protects adjacent tissues and collector channels and yields minimal scarring and inflammation. ELIOS can be performed as a standalone procedure or in combination with phacoemulsification. The learning curve is short, especially for those familiar with intraoperative gonioscopy.
Initial Outcomes With ELIOS
My colleagues and I analyzed early outcomes of phaco-ELIOS in 21 eyes of 13 patients.3 We found that mean IOP decreased from 15.1±3.9 mm Hg at baseline to 12.7 ±4.3 mm Hg at 1 month and 12.5 ±2.9 mm Hg at 3 months. The mean number of medications decreased from 2.2 ±1.3 at baseline to 1.8 ±1.4 at 1 month and 1.6 ±1.4 at 3 months. Success (>20% IOP reduction or reduction in medication) was achieved in 76% of eyes (n = 16). Overall, our first impressions have been very encouraging, and we are motivated to continue to offer this treatment to patients.
Current Evidence
Published studies report a 20% to 40% IOP reduction and a decrease in medications with ELIOS.2,4 Phaco-ELIOS may yield greater IOP lowering than standalone ELIOS or cataract surgery. In one randomized controlled trial, ELIOS yielded greater IOP lowering than SLT, although the sample size was small and not all findings were statistically significant.5 Complications, while rare, are generally early, mild, and transient.
Two long-term studies of ELIOS and phaco-ELIOS6,7 have shown sustained IOP lowering to the midteens for up to 8 years and a decrease in the number of medications for several years. The safety profile of ELIOS was favorable in both investigations.
1. Vogel M, Lauritzen K, Quentin CD. Targeted ablation of the trabecular meshwork with excimer laser in primary open-angle glaucoma. Ophthalmologe .1996;93(5):565-568.
2. Berlin MS, Toteberg-Harms M, Kim E, et al. Excimer laser trabeculostomy: the laser-based MIGS procedure for open-angle glaucoma. In: Samples JR, Ahmed IIK, eds. New Concepts of Glaucoma Surgery Series. 2020; 231-244.
3. De Crom RMPC, Beckers HJM. Initial results of combined phaco-emulsification with excimer laser trabeculostomy in glaucoma patients in The Netherlands. Poster presented at: the EGS meeting. June 2024; Dublin.
4. Babighian S, Caretti L, Tavolato M, et al. Excimer laser trabeculotomy vs 180 degrees selective laser trabeculoplasty in primary open-angle glaucoma. A 2-year randomized, controlled trial. Eye (Lond). 2010;24(4):632-638.
5. Durr GM, Toteberg-Harms M, Lewis R, et al. Current review of excimer laser trabeculostomy. Eye Vis (Lond). 2020;7:24.
6. Riesen M, Funk J, Toteberg-Harms M. Long-term treatment success and safety of combined phacoemulsification plus excimer laser trabeculostomy: an 8-year follow-up study. Graefes Arch Clin Exp Ophthalmol. 2022;260(5):1611-1621.
7. Berlin MS, Shakibkhou J, Tilakaratna N, et al. Eight-year follow-up of excimer laser trabeculostomy alone and combined with phacoemulsification in patients with open-angle glaucoma. J Cataract Refract Surg. 2022;48(7):838-843.
