I have tried to write a letter of thanks but don’t know what to say or even how to begin. I don’t know the persons I am writing to, but part of their loved one is literally now a part of me.

It began with a phone call from my brother. “Jim, what the hell is Fuchs’ Dystrophy anyway – do you have it too?”

I racked my brain and tried to dust off distant learning from medical school, but I had to turn to the Internet for answers. My brother had begun to have hazy vision and could no longer follow the flight of a golf ball, or even a hard line drive in baseball. He couldn’t read clearly until early afternoon. The problem was that his cornea (the outer layer of the eye) was waterlogged. Blowing a hairdryer into his eyes helped some as did a strong solution of salt water – but these really didn’t help enough and the problem was worsening.

His ophthalmologist explained to him that this was an inherited disease. Our parents had passed away and we knew that their eyesight wasn’t the greatest in their 80’s and 90’s but they were never diagnosed with Fuchs. The treatment options were explained to him: no treatment (leading possibly to scarring and blindness), the traditional corneal transplant, or the relatively new Descemet’s membrane transplant (called DSAEK which is basically a partial corneal transplant).

The cornea, I discovered, is an absolutely amazing part of our body. This window for our vision has five layers and, with its curvature, provides two-thirds of the refraction needed for clear vision. The innermost layer, the endothelium, produces Descemet’s membrane. The function of this region is to pump water out of the cornea to keep it crystalline clear. So basically it’s our own sump pump built into the cornea. In Fuchs, the endothelial cells start to die off prematurely and consequently the cornea starts to swell affecting vision.

So my brother underwent the DSAEK procedure in both eyes and had a stunning result. He’s now back to golf (without a spotter) and has excellent vision.

But then it was my turn. I thought initially it was cataracts, but it turned out that I was, like my brother, in the unlucky 50% inheritance chain. The procedure felt strange. I was in my own clinic where I knew everyone, but they appropriately kept a professional demeanor asking my name and birth date three times as part of the safety controls. The corneal surgeon had extensive experience and my confidence was high. The procedure was under local with “conscious sedation.” After an tiny incision and stripping a button of the ineffective endothelium from my eye, a similar sized button from a cadaver was inserted. An air bubble was then introduced to keep the graft in place while I laid on my back for an hour before going home and lying on my back some more. Amazingly the vision after 4 days cleared, the images were sharp and the halos gone.

So what about the cadaver? I hadn’t given my donor much thought until I tried to write a letter of thanks to the loved ones. My transplant of course was pretty minor compared to a kidney or lung transplant, yet every time I open my eyes I’m most thankful that someone was so thoughtful in giving part of themselves to others.

I had so many questions. What happened to my donor? How old? Was it expected or sudden? How can I really express my thankfulness? I’ve always checked the box “organ donor” on my driver’s license but never really given it much thought. But the fact is I now am literally seeing more clearly through another’s eyes as I write this. An anonymous gift of one person to the person of another. I still must try to write the letter.

Jim deMaine is a pulmonary physician who blogs at End of Life – thoughts from an MD.

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