Ocular GvHD is diagnosed in approximatley 40 to 60% of leukemia patients who undergo a stem cell transplant. I did not escape the odds this time. I spent the last week and a half at the Alkek Eye Institute at Baylor College of Medicine in Houston. Doctors there are fitting me for the PROSE system (prosthetic replacement of the ocular surface ecosystem) of scleral lenses developed by Boston Sight. As suspected, the ocular GvHD resulting from my stem cell transplant caused such a severe dry eye condition that I actually had areas of erosion in the surface of my corneas. The PROSE system consists of large hard contact lenses that hold a reservoir of saline solution against the corneas to encourage healing and to decrease pain. The lenses are very large, sit on the whites of the eyes, and are very hard to insert. The process of fitting and manufacturing new lenses until the fit is perfect could take up to 6 months. I have worked all week to learn how to insert the lenses and have reduced the failure rate from 15 attempts per eye down to about 5 attempts per eye. Mary Pat and our neighbors have learned a few new curse words in the process.
As part of the treatment, my doctor experimented with a new device designed to send an electric shock into the sinuses to stimulate tear production. The True Tear system from Allergan was approved by the FDA to stimulate tear production. The theory is that sometimes the neural pathway designed to communicate to the tear glands that the eyes are dry does not work properly. The electric shocks are designed to bypass that pathway to encourage the tear glands to secrete tears in the eys. My doctor tried the device on me but unfortunately, it did not work. Apparently, the ocular GvHD has damaged the lacrimal (tear) glands themselves such that they cannot produce sufficient tears even if they are stimulated with electric shocks. That’s too bad. It would be a lot simpler to simply shock them into overdrive whenever my dry eyes started causing pain. Mary Pat asked if she could use a dog shock collar on me instead. That’s something she has been threatening to do for years. My doctor was amused but assured her that a shock collar would not help my eyes even though it might help our marriage.