The glaucoma toolbox is expanding to include laser, drug delivery systems and minimally invasive glaucoma surgery.
The glaucoma toolbox is expanding to include laser, drug delivery systems, and minimally invasive glaucoma surgery (MIGS). This allows glaucoma specialists to tailor the treatment options to their patients, according to Dr Inder Paul Singh.
“The earlier the intervention, the higher the target IOP, the less aggressive physicians have to be,” said Dr Singh, of The Eye Centers of Racine & Kenosha in Wisconsin.
Patient adherence has historically been low or nonexistent due to a number of factors, and the reason for the advent of so many new technologies in the subspecialty. “Patients are basically [nonadherent],” he stated.
Considering this, Dr Singh explained his newly adopted philosophy. Glaucoma progression and controlled glaucoma are defined by IOP, visual fields, and the optic nerve, but he has added quality of life to the mix. Patients with ocular tearing, redness, and crusting are not adherent and do not have controlled glaucoma.
His new treatment regimen starts with selective laser trabeculoplasty (SLT) as the first-line therapy, followed by MIGS and laser or subconjunctival MIGS. He uses drug delivery and medication as needed. All the therapies can be used at the time that is best for dealing with adherence, he explained.
Dr Singh’s argument for using SLT as a first-line therapy is that it is physiologic and helps to address the actual pathology of the disease. He cited the results of the LiGHT trial, in which 356 patients were treated with SLT and 362 received latanoprost eye drops. The respective percentages that reached the target IOP were 95% and 93.1%; almost three-fourths of those treated with SLT did not need drops for 3 years after the laser treatment.
“No one in the SLT group progressed to needing incisional surgery, and 11 patients in the [eye] drop group needed surgery,” Dr Singh said. “SLT was also more cost-effective [and] as a first-line therapy makes sense. There is a better response when SLT is the first-line treatment.”
Dr Singh’s pearl for helping patients accept the idea of undergoing SLT as their first glaucoma therapy is to avoid using the word “laser.” Instead, he describes it as a “beam of light” that enters the eye during an office-based procedure requiring about 1 minute. He explained that the treatment excites the eye’s natural draining ability to produce the release of enzymes to rejuvenate the drain. Importantly, the procedure is covered by insurance.
In cases in which SLT alone is insufficient, drug delivery can be the next step. Bimatoprost SR (sustained-release; Durysta, Allergan) is a biodegradable implant used to treat open-angle glaucoma or ocular hypertension. The drug is released over a minimum of 4 months and relieves the need for drop instillation; in some patients, the insert can last up to 2 years.
The insertion procedure is performed at the slit lamp without the need for a speculum. The patient is instructed to look at a fixation target and the patient experience is similar to an IOP measurement. The physician presses a button to insert the implant and exits the eye.
Drug delivery can be used in patients with adherence issues to treat any glaucoma type.
Surgeons have a number of MIGS options from which to choose depending on the patient.
“The introduction of [the] MIGS procedure has spawned a great deal of new research and technology advancements,” Dr Singh said.
Conventional outflow MIGS includes outflow stents approved for use at the time of cataract surgery (iStent inject, Glaukos; Hydrus Microstent, Alcon); MIGS that dilates the outflow system that is approved for use with cataract surgery and as a stand-alone procedure (iTrack/ABiC, Ellex; Visco 360 Viscosurgical System/Omni Surgical System, Sight Sciences); and trabecular meshwork stripping or removal (Kahook Dual Blade/Trabectome, New World Medical; gonioscopy-assisted transluminal trabulectomy/Omni, Sight Sciences) also approved for use during cataract surgery and as a stand-alone procedure.
“My advice to ophthalmologists is to become familiar with the new treatments and devices and pick one from each of the categories,” Dr Singh said.
He also recommended that ophthalmologists obtain the best view possible gonioscopically, regardless of the treatment used.
“The view is key to any MIGS procedure,” he stated.
Mixing the MIGS procedures is also an option. For example, viscodilation and inserting a stent simultaneously may be beneficial, especially for patients taking multiple medications.