In this episode of Interventional Mindset, Mark Gallardo, MD, of El Paso Eye Surgeons, sits down with Steven R. Sarkisian, Jr., MD, of Oklahoma Eye Surgeons, to discuss 24-month results from the US pivotal trial of the ELIOS System excimer laser trabeculostomy (ELT) combined with cataract surgery (ELIOS-phaco). Both surgeons were trial investigators and lead authors of the 24-month report, published in September 2026 in Ophthalmology Glaucoma.1
ELIOS fast facts
- ELIOS (Bausch + Lomb) uses a non-thermal 308-nm excimer laser to create 10 microchannels, each 210 µm in diameter, across roughly 90° of inferonasal trabecular meshwork, leaving no implant.1
- Excimer photoablation breaks molecular bonds at the tissue surface, producing well-delineated channels with limited inflammation and wound-healing response.1
- ELIOS has been CE-marked in Europe since 2014 but remains investigational in the US.1,2
- In a Swiss cohort of 161 eyes followed 8 years after ELIOS-phaco, mean intraocular pressure (IOP) fell from 19.3 to 15.4 mm Hg, stayed at least 20% below baseline from month 3 onward, and 25.5% of eyes needed subsequent IOP-lowering surgery.3
What the 24-month pivotal data show
Because cataract surgery alone lowers IOP, a phaco-MIGS trial must show benefits beyond phaco. The ELIOS investigators set each performance goal at the upper bound of the 95% confidence interval from pooled phaco-only arms of the Hydrus, iStent inject, and CyPass pivotal trials, so the combined procedure had to beat the most favorable plausible phaco-only result.1
"We always know that the pressure is going to be lower if you do an intervention at the time of phaco besides just phaco."—Steven R. Sarkisian, Jr., MD
The nonrandomized trial enrolled adults with mild-to-moderate POAG at 20 US sites. Eligible eyes had medicated IOP of 24 mmHg or less on one to three medications and unmedicated diurnal IOP (DIOP) of 22 to 34 mmHg after washout.1
Among 318 treated patients, mean baseline unmedicated DIOP was 24.53 mmHg, and 69.8% used one medication at screening. Investigators considered randomization to cataract surgery alone ethically difficult when microinvasive glaucoma surgery (MIGS) is routinely available.1
"The FDA allowed us to treat everybody in the clinical trial with ELT, which I think was very ethical in nature."—Mark Gallardo, MD
Both coprimary endpoints were met at 12 and 24 months:1
- ≥20% reduction in unmedicated DIOP: 84.2% at 12 months (goal >79%) and 76.1% at 24 months (goal >68.5%)
- Mean change in unmedicated DIOP: −8.17 mmHg at 12 months (goal ≤−7.2) and −7.35 mmHg at 24 months (goal ≤−6.15)
- Mean unmedicated DIOP: 15.98 mmHg at 12 months and 16.76 mmHg at 24 months
- Medications: mean 1.5 at screening vs. 0.3 at month 23, when 82.0% of patients were medication-free
However, the treatment response was weaker in two key subgroups: 60.5% of patients on three medications met the 20% threshold at 24 months, and eyes with prior selective laser trabeculoplasty (SLT) averaged −5.42 mmHg vs −7.83 mmHg without it.1
Phaco-only vs. combination procedures
Cautioning against cross-trial comparison, the authors report similar figures for Hydrus Microstent (86% and 77%, meeting the 20% threshold at 12 and 24 months; 78% medication-free) and iStent inject (76% at 24 months; 84% of responders medication-free).1
A retrospective study of 343 eyes at three European centers compared ELIOS-phaco directly with iStent inject or inject W plus phaco: at 12 months, mean IOP fell by a similar amount (21.6% vs. 20.7%), but more ELIOS-phaco eyes reduced medications (46.4% vs. 31.3%; p=0.02).4
In a 5-year post-hoc analysis of the randomized HORIZON trial, visual field loss progressed at −0.26 dB/year with cataract surgery plus a Schlemm’s canal microstent vs. −0.49 dB/year with cataract surgery alone.5
Patient selection for ELIOS
Dr. Sarkisian considers primary open-angle glaucoma (POAG), pseudoexfoliation, and pigmentary glaucoma good candidates and avoids ELT in active uveitic, neovascular, and iridocorneal endothelial syndrome glaucoma; the trial itself enrolled only POAG.1
Because ELIOS treats a defined arc without an implant, it can follow most other angle surgery, but may be particularly beneficial after canaloplasty where only a small goniotomy was performed, or stand alone iStent Infinite where the ELIOS wounds can be placed in the remaining nasal angle. Moreover, a surgeon can always move superiorly and treat in a different quadrant than any prior MIGS.
He estimates the learning curve at 5 to 10 cases. Dr. Gallardo reports pigmented rims around the channel openings in patients 4 years out, which he reads as a sign of sustained outflow through treated areas.
Safety
"It's astonishing how there is simply no sign of damage distal to the wound and in the canal at all."—Steven R. Sarkisian, Jr., MD (describing electron microscopy of ELIOS channels)
Regarding safety findings, no intra-operative adverse events occurred during the ELIOS step, and while 21.7% of patients had a post-operative ocular adverse event, 92.1% of them mild or moderate.1
Additional considerations for the ELIOS System’s safety profile:1
- Secondary surgical intervention: 2.2% through 24 months, vs. about 2.4% for Hydrus and 5.4% for iStent inject in their pivotal trials; a retrospective comparison found similarly low rates with ELIOS-phaco and iStent inject-phaco4
- Microhyphema: 9.4% of eyes at day 1, none from month 3 onward
- Median endothelial cell loss: 8.9% at month 3 and 9.6% at month 24, with no progressive decline
- Corrected distance visual acuity 20/40 or better: 99.3% at 24 months
In closing
Through 24 months, ELIOS-phaco met both coprimary endpoints without leaving an implant in the angle: mean unmedicated DIOP fell 7.35 mmHg from baseline, and 82.0% of patients were medication-free at month 23.1
The clearest candidate is a patient with mild-to-moderate POAG on one or two medications who is already scheduled for cataract surgery; eyes on three medications or with prior SLT respond less.1
Outside this trial, ELIOS-phaco outcomes resemble those reported in the Hydrus and iStent inject pivotal trials, and a retrospective comparison found 12-month IOP reduction similar to iStent inject-phaco; none of these comparisons is randomized.1,4
Because ELIOS preserves most of the trabecular meshwork, it keeps later angle surgery on the table. Take note that US use awaits FDA approval and reimbursement.
This article was produced by our editorial team in collaboration with subject-matter experts. AI may have been used as an editorial tool under the direction of human editors, who reviewed and approved all content.
