In this episode of Inside Intrepid, Nate Lighthizer, OD, FAAO, FAAOMS and Justin Schweitzer, OD, FAAO, discuss how research over the last decade has changed the way clinicians view selective laser trabeculoplasty (SLT). They explain why this change happened, how to identify patients who may benefit, and touch on new advancements, such as direct SLT (DSLT).
Dr. Lighthizer is a renowned optometrist, dean, and a professor at Northeastern State University Oklahoma College of Optometry. When he isn’t teaching, Dr. Lighthizer specializes in ocular diseases, such as glaucoma, laser procedures, and electrodiagnostics.
Dr. Schweitzer is an optometrist, published author, and Externship Director at Vance Thompson Vision, in Sioux Falls South Dakota. He has special interests in glaucoma and minimally invasive glaucoma surgery. He’s active in several professional organizations and passionate about sharing his knowledge with others.
SLT as a first-line glaucoma therapy fast facts:
- SLT was traditionally considered a second-line glaucoma treatment, but thanks to a growing body of evidence, many clinicians now use it as a first-line approach.
- The procedure reduces the need for topical glaucoma medications, saving patients time and making treatment easier to manage.
- Patients with higher intraocular pressure (IOP) tend to be the best candidates for SLT, as they often achieve more noticeable results.
- SLT can be incorporated into larger glaucoma treatment strategies, including for patients already using medication.
- The effects of SLT can last for several years, and the procedure can be repeated for most patients once they wear off.
Deeper dive: Reframing SLT as a first-line glaucoma therapy
Dr. Lighthizer and Dr. Schweitzer discussed how much glaucoma treatment has changed over the last decade. They noted that medication and topical treatments, such as eye drops, used to be the first line of defense for patients with open-angle glaucoma or ocular hypertension, while SLT was typically recommended later on, if a patient needed additional help managing IOP.
That thinking started to change with the release of the LiGHT trial, which found that SLT was safer and more effective than eyedrops. Specifically, it found that nearly 70% of eyes treated with SLT remained at or below their target IOP without the need for medical treatment for up to 6 years.1 A subsequent analysis of the LiGHT trial found that SLT slowed visual field progression by nearly 30%.2
“The LiGHT trial really shoved this first line, saying SLT not could be but should be offered as a first-line therapy, supporting a change in clinical practice.”
Why SLT should be considered a first-line treatment
In addition to the new research, Dr. Lighthizer and Dr. Schweitzer highlighted several other reasons clinicians should consider implementing SLT as a first-line glaucoma treatment. These reasons include:
Reduced medication burden
Glaucoma patients often struggle to use prescription eye drops properly. In fact, one study found that up to 50% of these individuals fail to receive the intended benefits of treatment.3 Dr. Schweitzer said SLT can reduce some of that burden and help patients better adhere to their treatment plan.
Potential for improved IOP reduction
SLT may be particularly beneficial for patients with higher baseline IOP. Dr. Lighthizer noted that those with a starting IOP of between 22 and 25mmHg often experience a 20 to 30% drop in IOP.
Long-term disease control
The LiGHT trial found that patients who received SLT as a first-line glaucoma therapy experienced a lower rate of disease progression (19.6%) compared to those who used eyedrops first (26.8%).1
To be clear, SLT isn’t the right solution for everyone. However, since it has such potential, Dr. Lighthizer and Dr. Schweitzer encouraged clinicians to introduce it in their first-line treatment discussions.
Selecting patients who may benefit from first-line SLT
SLT should be considered on a case-by-case basis, but certain patient characteristics can help guide your decision-making.
Dr. Lighthizer and Dr. Schweitzer noted that two factors are particularly important: whether the patient has higher baseline IOP and the number of medications they’re using to manage their glaucoma. Those with higher IOP and on fewer glaucoma medications typically experience a more noticeable IOP-lowering response to SLT.
Another thing to consider is the type of glaucoma a patient has. SLT can be used to treat:
- Primary open-angle glaucoma (POAG)
- Ocular hypertension
- Low-tension glaucoma
- Pigment dispersion and pigmentary glaucoma
- Pseudoexfoliative glaucoma
Finally, Dr. Lighthizer and Dr. Schweitzer emphasized that no two treatment recommendations are exactly alike. SLT and eye drops aren’t either/or. If a patient is already using eye drops, but their IOP remains high, SLT offers an alternative to additional medication.
SLT as part of long-term glaucoma management
“[Patients] need to understand that the effect is going to wear off at some point. But the good news is when the effect wears off, we can do this again. The repeatability is a very strong aspect of SLT.”
Even though SLT is considered a first-line treatment, it isn’t necessarily a one-and-done procedure. There’s no cure for glaucoma, so regular monitoring and ongoing management are necessary to prevent vision loss and other negative outcomes.
Despite that fact, Dr. Lighthizer and Dr. Schweitzer said that SLT can be integrated into long-term glaucoma treatment strategies. They added that many patients only need follow-up treatment every 3 to 5 or 3 to 7 years, and because the laser is gentle, there’s little risk beyond temporary inflammation or elevated IOP.
What about direct selective laser trabeculoplasty?
Direct SLT is a newer type of SLT designed to make treatment faster and more comfortable. As a result, many clinicians are beginning to compare the two procedures.
Research is ongoing, but the GLAURious trial found that while DSLT safely lowered IOP in participants for up to a year, at the 6-month mark it didn’t perform well enough to be considered equivalent to SLT, while at 1 year it was essentially equivalent.4
“Our experience has been that it's probably not quite as effective as SLT, maybe a few mmHG lower, which is what we saw in the GLAURIOUS trial at 6 months, but at 1 year it was basically equivalent.”
Consider SLT as a first-line treatment option
For any clinician specializing in glaucoma, including SLT as a first-line treatment makes a lot of sense. Research confirms that in many cases, SLT is just as, if not more, effective than traditional medications. At the same time, it can support treatment adherence, and its repeatability makes it a steady revenue stream.
Even if you live in a state that doesn’t allow optometrists to perform SLT, Drs. Lighthizer and Schweitzer said you should know enough about it to discuss it with your patients. It can also be beneficial to partner with an ophthalmologist whom you can refer patients to.
Dr. Schweitzer concluded: "To all the optometrists out there listening today: [SLT] has got to be in your arsenal as a discussion point. I love [eye] drops; I use them every single day, and they’re still an important part of the way I manage my patients. But we all have taken the oath in optometry school to do what’s best for our patients. To educate [them] properly."
This article was written by Chad Birt based on the recorded conversation between Drs. Schweitzer and Lighthizer.
