 | Glaucoma: What Every Patient Should Know |  |
|---|---|---|
| Previous Section | Next Section |
| Glaucoma: What Every Patient Should Know | |
|---|---|---|
| Previous Section | Next Section |
Almost 40 years ago, a brilliant doctor named David Worthen tried to lower eye pressure by shining laser energy (ALT) at the meshwork in a controlled trial. Considering that he was working with advanced glaucoma eyes, the beneficial effect was pretty impressive, though small. Five years later, Dr. James Wise reported that when he treated fairly early glaucoma patients, their eye pressures fell impressively, and since then, a large controlled trial (the Glaucoma Laser Trial) showed that there is sustained lowering of pressure by this treatment as initial therapy. The meshwork runs all around the eye in a circle, so treatment generally is either half the circle or all the way around (360 degrees). Even more recently, a study in the United Kingdom found that initial SLT laser treatment was a very promising approach and outperformed initial eye drops in some important measures. It needed to be repeated in some persons and 25% still required taking eye drops after 36 months to reach the intended eye pressure lowering.
The good points of laser angle treatment are that it is nearly impossible to hurt vision or the eye when done properly, and, having laser treatment doesn’t prevent a person from later using other treatments to lower eye pressure if the laser doesn’t work. The eye is numbed with a drop and it takes about 5 minutes to do. During the procedure, a person can feel a sensation of pressure from the examining lens that holds the eye open and allows the doctor to see where the treatment is done. When it is over, there is a feeling of light sensitivity and grittiness of the eye, but the vision is nearly normal immediately.
Sometimes we recognize that laser angle treatment has stopped working and that drops or surgery are now needed. Every glaucoma treatment approach sometimes stops working after a period of control. This can be because the disease gets worse and the baseline pressure is rising, making it look like the treatment has become less effective. Continued monitoring in the doctor’s office is needed to be sure that initial treatment continues to work.
During the last 10 years, a different type of laser energy has become popular and tested extensively (including in the United Kingdom study discussed above). Selective laser trabeculoplasty or SLT, delivers the laser light over a wider area and at lower power. SLT, like ALT, can be later repeated after a period of successful IOP-lowering. The way in which both types of LTP work is most likely by producing a micro-injury to the trabecular meshwork that is treated, releasing beneficial chemicals (cytokines) that over a month or so alter the eye tissues to allow aqueous humor to later get out of the eye faster.
If you would like to support the cost of providing and maintaining this book with a charitable donation of any size, please click here.