Eye Didn't Know!

Are we due for a new class of glaucoma medications?

Did you know? It has been twelve years since there have been any significant additions to our supply of medications for glaucoma. In 1996 Xalatan was introduced, the first of the prostaglandin agents which quickly took over first-line therapy for most glaucoma patients. The prostaglandins simply worked better with fewer side effects than the other medications available.

A new class of medication may be on the horizon. Rho-kinase inhibitors, (ROCK-inhibitors) are molecules which relax smooth muscle, a muscle which is found, among other places, in the drainage system within the eye.

When this drain does not work properly, the pressure within the eye rises, which can lead to damage to the optic nerve within the eye. When this happens, vision can be lost, and we call it glaucoma. Relaxing the mesh-like tissue within this drain can apparently cause pressure to be lowered.

Several pharmaceutical companies are looking into these molecules. Studies in monkeys have shown a larger pressure lowering effect than Xalatan!

Will these studies result in a new class of glaucoma medications? Only time will tell. Ophthalmologists and glaucoma patients could benefit from a new arrow in our quiver!

More information can be found here.

Did you also know? Statin drugs (lipid-lowering agents) such as Lipitor, Zocor and Crestor are also ROCK-inhibitors.

Measuring Eye Pressure

Did you know? Until 1905 there was no objective way to measure pressure within the eye. In that year, Norwegian ophthalmologist Hjalmar Schiotz invented the first tonometer, which now bears his name, the Schiotz tonometer.

Until this time, doctors estimated pressure within the eye by pushing on the eye through the eyelid, and guessing, much like you might push on a bicycle tire with your thumb and guess the pressure. The Schiotz tonometer actually works in much the same way, it measures the weight necessary to indent the cornea a standard amount.

Knowing the pressure more accurately allows us to better diagnose and treat glaucoma, a disease usually caused by elevated eye pressure damaging the optic nerve.

The Schiotz tonometer is still used in many parts of the world, and when I trained, it was what most doctors used as a portable tonometer.

Did you also know? Dr. Schiotz was also responsible for introducing the concept of sterilizing surgical instruments (by boiling) to Norway.

"You use lasers to remove cataracts, right?

Did you know that cataracts are NOT removed with a laser? Ophthalmologists use many types of lasers for dozens of indications, but removing cataracts is not one of them! The state of the art in cataract removal today is called phacoemulsification, which uses a tiny probe to dissolve the cloudy lens and remove it from inside the eye. After the cataract is removed, a soft, rolled-up implant made of silicone or acrylic is inserted through a three millimeter incision, and unfolds in place within the eye. Because the tiny incision heals very quickly, it is unusual to have any restrictions on activities after surgery.

Did you also know? Most modern cataract surgeries take less than 15 minutes, and many doctors only use eyedrops (no needles!) to anesthetize the eye.