The list of first-line therapies for glaucoma has grown in recent years. We’ve seen the addition of new drug options and combinations, as well as the evidence that selective laser trabeculoplasty (SLT) is a robust first-line option, rather than just a second-tier choice after medication. Many in ophthalmology are exploring how to approach the decision of first-line therapy: Should they prescribe drops first or start with SLT?

Both are effective glaucoma therapies, but you have to consider several factors when deciding on what to prescribe to each patient, including the patient’s individual disease state, overall health and lifestyle considerations.

SLT AS FIRST-LINE THERAPY

Determining candidates

When I see a patient who is newly diagnosed with glaucoma and makes a good candidate for SLT, I offer the procedure as first-line therapy. I suggest drops as an alternative choice and allow patients to make the decision after I explain both options. Patients who are good SLT candidates are those with open-angle glaucoma, including low-tension glaucoma, pseudoexfoliative glaucoma, and pigmentary dispersion syndrome. For these patients, I use two different SLT devices at different locations: the Ellex Solo and the Lumenis Selecta.

Evidence and benefits

SLT has long been an excellent choice for early treatment, introduced more than 20 years ago by Lumenis; however, medication has typically remained the first step in treatment. In 2018, the Laser in Glaucoma and Ocular Hypertension (LiGHT) study gave practitioners a high degree of confidence in the safety and efficacy of SLT as a first-line therapy for open-angle glaucoma. (See “Key points from the LiGHT study”.) Specifically, SLT patients were within their target pressures at more follow-up visits (93% of visits vs 91.3% with medication), did not need surgery for glaucoma (0 cases vs 11 cases) and were less likely to show disease progression (23 vs 36 cases).¹

In addition to potentially offering better pressure control, SLT has other advantages over medication. For younger patients, SLT can prevent or delay the long-term side effects caused by decades of medication use. In older patients, the practical benefits shine. For some, arthritis or neck problems make it physically difficult to use eyedrops. Low vision and poor dexterity can also impair their ability to use eyedrops.

Compliance is a problem in all age groups, whether the problem is cognitive impairment or simply a busy schedule. If ocular surface problems make it uncomfortable to instill eyedrops, compliance is even more challenging. Any compliance problem can make a patient fall short of goals for pressure control.

Patient and referral education

In my experience, patients have some trepidation about undergoing a procedure, but many are curious about laser procedures or about getting the most advanced therapy. When properly explained, the ease of the SLT procedure is very attractive to patients and they become very open to the procedure. Discussions should include the fact that SLT can be done the same day in the office with topical anesthesia, they can drive themselves home and there are no restrictions after SLT. Also, images and video can be used to educate patients about the relative ease and speed of SLT, which help make it a good first-line option. I have not yet trialed the new Digital Duet SLT/YAG platform from Lumenis, but the system incorporates image and video capture to support patient education as well as our other needs.

In my practice, we host CME events to update referring optometrists on the efficacy and safety of SLT and make sure they understand that they can refer patients before starting them on medication. We want them to know how today’s advanced laser technologies, optics and outcomes have been studied and proven to be very promising. A close comanagement partnership between educated ophthalmologists and optometrists ensures that patients have access to SLT and other advanced procedures for glaucoma.

MEDICATION AS FIRST-LINE THERAPY

Patient selection

Medication is my first recommendation for patients who are not good candidates for SLT. Patients might not be candidates for SLT if they have a prior history of uveitis, herpetic disease in the eye, narrow angles, angle recession or corneal issues that prevent getting a good view of the angle. In addition, some patients choose medication over SLT because they are newly diagnosed with glaucoma and do not yet feel comfortable agreeing to a procedure. Those patients usually start with drops as they learn about their disease process and become more comfortable with the diagnosis — and with me as their new glaucoma specialist.

Medication choices

Prostaglandin analogs are generally the first choice for primary open-angle glaucoma because these drugs offer an excellent bang for the buck, lowering pressure with one-time dosing in very well-tolerated drops. Many practitioners choose latanoprost (Xalatan, Pfizer), which most insurances prefer patients choose in generic form. If the first-choice medication is not effective in controlling pressure, I try to get a deeper understanding of how noncompliance could factor into the results. We discuss the challenges that patients face so we can factor their individual needs into their pressure management plan. I bring up the SLT option at this point once again, if appropriate. Otherwise, my usual choice for a second medication is a fixed-combination dorzolamide-timolol (Cosopt, Merck) taken 2 times a day in patients without contraindications. If there is any question of compliance with the medication — for example, if I think the patient may have difficulty remembering to use multiple doses — I might stick to a once-daily dosing with a combination of latanoprost and ROCK inhibitor netarsudil (Rocklatan, Aerie). The ROCK inhibitor is the newest class on the market, and this combination has been shown to reduce pressure to 16 mm Hg or below in nearly 60% of patients, compared to 37% with latanoprost alone.²

SECOND-LINE THERAPY

Patient examples

Some of my patients have been using medication long term. Perhaps they were well controlled on medication long before SLT became an accepted first-line option and were not inclined to change. In other cases, I see new patients who have managed glaucoma with practitioners who have not recommended any procedures. These patients find me when they’re searching for alternatives to eyedrops.

When to move from medication

Long-term medication users might need SLT or another minimally invasive procedure because they no longer reach target pressures with medication alone. It’s also common to use SLT as a second-line therapy because of a tolerability problem.

Patients who have been using glaucoma medications for years often develop symptoms of ocular surface disease, such as irritation, dryness, redness and intolerance to their medications. Even patients who have been maintained on a medication regimen for years can develop these symptoms.

One cause of the ocular surface toxicity is the irritating preservatives used in some eyedrop medications. In this regard, some generics have BAK that their brand name counterparts lack (eg, travoprost vs Travatan Z [Alcon], latanoprost vs Xelpros [Sun Ophthalmics]) or higher concentration of drug that may also cause issues (brimonidine and bimatoprost vs Alphagan [Allergan] and Lumigan 0.01 [Allergan]).

Tolerance also can decrease as people age and their meibomian gland function diminishes, weakening one of their eyes’ natural protections. When we perform SLT for these patients, allowing them to reduce or eliminate their use of glaucoma drops, we see clinical improvement in the ocular surface as well as easing of the patient’s symptoms.

LOOKING AHEAD

As the choices we make today between SLT and medications for first-line therapy become routine, the array of choices will no doubt grow and evolve. ROCK inhibitors are a new and promising addition to prostaglandins for bringing patients’ pressures within target range with once-a-day dosing.

I have seen the clarity, accuracy and ease of use for the Ellex Solo and the Lumenis Selecta Duet improve over time, and I’m looking forward to trialing the fully digital Lumenis Digital Duet SLT-YAG platform, which incorporates imaging technologies that can help surgeons teach residents as well as document findings for research.

With advances in both laser technologies and medications, we continually become better positioned to help patients reach target pressures and slow or prevent progression and vision loss from glaucoma. OM

REFERENCES

1. Konstantakopoulou E, Gazzard G, Vickerstaff V, et al. The Laser in Glaucoma and Ocular Hypertension (LiGHT) trial. A multicentre randomised controlled trial: baseline patient characteristics. Br J Ophthalmol. 2018;102:599-603.
2. Asrani S, Bacharach J, Holland E, et al. Fixed-Dose Combination of Netarsudil and Latanoprost in Ocular Hypertension and Open-Angle Glaucoma: Pooled Efficacy/Safety Analysis of Phase 3 MERCURY-1 and -2. Adv Ther. 2020;37:1620-1631.
3. Wong MO, Lee JW, Choy BN, Chan JCH, Lai JSM. Systematic review and meta-analysis on the efficacy of selective laser trabeculoplasty in open-angle glaucoma. Surv Ophthalmol. 2015;60:36-50.

About the Author

Kristin O. Chapman, MD, is a glaucoma specialist and comprehensive ophthalmologist at The Eye Institute of Utah in Salt Lake City.

Dr. Chapman revealed no relevant disclosures.