A New Era in Excimer Lasers

The excimer laser has never been better at doing what we ask of it. What defines the new era is how little translation that request may require. Some of the latest platforms can treat eyes directly from the manifest refraction without a surgeon-specific nomogram adjustment; others use modern diagnostics to generate an individualized treatment plan and transfer it directly to the laser. At the same time, these diagnostic instruments help determine which patients will be best served by an excimer laser procedure and which might be better served by another option.

AN EXTRA STEP AND ITS ELIMINATION

For most of the excimer laser's history, outcomes have been refined through nomograms. In many cases, we surgeons use nomogram software such as Internet Based Refractive Analysis (Zubisoft) or Data Link (SurgiVision) to enter our outcomes and receive a nomogram that informs future treatments. This feedback loop works, but it adds a step between measurement and treatment, reflecting a gap between what we measured, what we programmed, and what ultimately produced our best results.

We have pursued a more direct pathway before. More than 15 years ago, the promise of the CustomVue platform (Visx) was that we could capture a diagnostic image, transfer it to the laser system, and achieve 20/20 vision for our patients. In practice, however, accommodation during diagnostic testing and untreated dry eye disease, among other factors, can skew refractive measurements. No ablation profile is immune to unreliable data.

Some of the latest excimer laser systems attempt to address these issues. In the US FDA clinical trial of the Teneo 317 Model 2 excimer laser (Bausch + Lomb), no nomogram adjustments were made. The patient's manifest refraction was entered directly as the treatment input.¹

Alcon has taken a complementary approach with WaveLight Plus, its automated ray-tracing-guided (RTG) treatment profile. The Sightmap (Alcon) creates an individualized optical model of the eye and transfers the ray-traced treatment plan directly to the laser. Here again, more of the planning burden is shifting from the surgeon's spreadsheet to the platform itself.

OUTCOMES

Across platforms, the trend is toward more individualized planning and more direct treatment delivery.

Teneo

The Teneo trial illustrated what direct-manifest treatment can deliver. Approximately 98% of eyes achieved 20/25 uncorrected distance visual acuity (UDVA) or better at 9 months, and 92.7% were within ±0.50 D of the intended correction.¹

Patients' quality of vision is equally relevant. In a prospective study conducted at 10 US clinical sites, 168 patients who underwent LASIK with the Teneo - again with no nomogram adjustments - completed the Patient-Reported Outcomes With LASIK questionnaire preoperatively and 9 months postoperatively.²

Patients' mesopic contrast sensitivity had improved significantly at 3, 6, and 12 cycles per degree with glare and at 6 and 12 cycles per degree without glare. They also reported significantly less difficulty driving at night and fewer starbursts, halos, and episodes of blurry vision. More than 98% of the patients were satisfied with their postoperative vision.^1,2

A similar pattern was observed in an analysis of 155 highly myopic eyes with a mean preoperative spherical equivalent of -7.99 D. At 9 months, 94.8% of these eyes had 20/25 UDVA or better, and 87.7% were within ±0.50 D of the refractive target. No nomogram adjustments were used.³

WaveLight

At the 2026 ASCRS Annual Meeting in Washington, DC, Maya S. Goyal, BSc, and I presented a retrospective comparison of 1,299 LASIK eyes.⁴ All flaps were created with the FS200 femtosecond laser (Alcon), and ablations were performed using wavefront-optimized (WFO), topography-guided (TCAT/Contoura [Alcon]), or WaveLight Plus RTG profiles.

The WFO group achieved a mean UDVA of 20/20, and the TCAT group achieved a mean UDVA that was better than 20/20. Outcomes were better still with RTG, which achieved a mean UDVA of -0.15 logMAR. In separate pairwise analyses, patients' mean UDVA was significantly better (P < .0001) after RTG compared with WFO treatment (48 eyes per group) or TCAT treatment (48 RTG eyes vs 359 TCAT eyes). In a separate 100-eye RTG cohort, 93% of eyes achieved 20/16 UDVA or better, 53% achieved 20/12.5 UDVA or better, and all achieved 20/20 UDVA or better at 3 months.⁴

iDesign

In a prospective, randomized, contralateral-eye trial, 100% of eyes had 20/20 UDVA or better 12 months after undergoing ocular wavefront-guided LASIK planned with the iDesign Advanced WaveScan Studio System (Johnson & Johnson Vision).⁵ In a matched comparison of 4,290 eyes per group, 95.9% of eyes treated with the current-generation system achieved 20/20 UDVA or better at 1 month; 97.3% of patients were satisfied; and glare, starbursts, and ghosting were significantly less frequent than with first-generation wavefront-guided treatment.⁶

MEL 90

The MEL 90 excimer laser (Carl Zeiss Meditec) may be used to treat myopia, hyperopia, and mixed astigmatism.⁷ In a series of 286 myopic LASIK eyes treated with the platform's Triple-A ablation profile and no nomogram adjustments, 92% achieved 20/20 UDVA or better, 88% were within ±0.50 D of the intended correction, and mesopic contrast sensitivity improved significantly.⁸ In the platform's approval study, more than 92% of patients reported being completely or very satisfied with their LASIK results.⁷

DIAGNOSTICS

The new era in excimer lasers is as much about what happens before ablation as what happens during treatment. Modern diagnostic systems can assess the anterior and posterior corneal surfaces, crystalline lens, anterior chamber depth, biometric parameters, and ocular surface during the same workup. This allows us to screen patients more effectively, sometimes leading us to recommend a different procedure.

Patients whose ocular anatomy or refractive error falls outside the comfort zone for corneal refractive surgery may be candidates for a phakic lens. Older patients may be better served by refractive lens exchange, which can also address presbyopic needs.

CONCLUSION

Modern laser systems and diagnostic instruments are helping us select the most appropriate refractive procedure for each patient and simplifying treatment. When the workup indicates that excimer laser ablation is not the best choice, we have a range of alternatives to offer.