Research compares glaucoma laser options

June 20, 2014

AHS seeks best procedure for repeat treatments

Story by Greg Harris; photo by Paul Rotzinger

Bruce MacArthur has been using eye drop medication to control his glaucoma since his late 30s, when he was first tested.

The condition runs in his family – his grandfather went blind because of it and his mother currently uses drops in both eyes to control hers.

Now 56, MacArthur has volunteered for a new research study in Calgary that’s weighing the merits of two types of laser therapy used to treat glaucoma.

Dr. Andrew Crichton examines the eye of glaucoma patient Bruce MacArthur“If some of the newer technology could free me from the daily need for drops, that would be great,” MacArthur says.

An Alberta Health Services ophthalmologist is part of a national study assessing whether selective laser trabeculoplasty (SLT) or argon laser trabeculoplasty (ALT) offer the best options for repeat treatments for glaucoma.

Glaucoma is a buildup of pressure in the eye that can lead to blindness if it goes untreated. There is no cure, and the condition can only be managed with eye drops, laser therapy or, in more serious cases, surgery. Glaucoma also tends to affect people as they age and is more common with certain conditions, such as diabetes.

“Surgery carries with it the risk of complications, so if we can offer patients the option of repeating laser therapy, that would generally be preferable,” says Dr. Andrew Crichton, the principal investigator of the Calgary arm of the study.

Although both types of laser therapy have been in use for a number of years, it’s not well understood which is best for repeat treatments.

ALT is the older of the two and has more of a heating effect than SLT. Theoretically, SLT might be more repeatable but the research has yet to bear that out. SLT is currently used more frequently than ALT. Patients in the study receive laser therapy at the Eye Clinic at Rockyview General Hospital.

“If an initial laser treatment has lost its effect, are you better off repeating the same laser or using the old-style laser? This is one of the questions we hope the research will help address,” Dr. Crichton says.

The research study is being led by the Lawson Health Research Institute, which is part of the London Health Sciences Centre in Ontario. Researchers are looking for 144 participants in five centres across Canada, of whom about 30 will be from Calgary.