Iโ€™ve already deleted the video twice. Since there arenโ€™t any Korean-language videos online about this rare inherited retinal disease I have, I felt like I should make one myselfโ€”not as a doctor, but as a patientโ€”sharing my experience and giving a general explanation of the condition. But every time I finish the video, I keep finding issues in my explanation, deleting it, and starting over again. 

The error I discovered this time was the order in which the structures of the eye degenerate in choroideremia

I had understood it as RPE (retinal pigment epithelium) โ†’ photoreceptors โ†’ choroid, but it turns out itโ€™s not something that can be stated so definitively. 

The main factor that keeps the choroidal blood vessels healthy is the VEGF signal sent from the RPE. So even before it reaches the photoreceptors, degeneration of the RPE alone is enough to drive degeneration of the choroid. 

But at the same time, photoreceptors are affected from the moment the RPE starts to fail. The RPE must function properly to recycle vitamin A, process outer segments, and break down the toxic byproducts formed when outer segments meet vitamin A derivatives. If the RPE canโ€™t perform these functions, photoreceptors die. And as the choroid atrophies and oxygen supply decreases, photoreceptors are further affected. 

So after the RPE is compromised, itโ€™s very difficult to say with 100% certainty whether photoreceptors die first or the choroid degenerates first. To understand diseases like this, researchers create explanatory modelsโ€”โ€œthis is probably how the disease developsโ€โ€”and depending on how that model is constructed, the interpretation can differ. Itโ€™s similar to how many different atomic models existed throughout history, evolving as new observations were made. Which means itโ€™s not something I, as a non-researcher, can claim with confidence. 

Iโ€™m struggling with how to adjust the tone of the video. Itโ€™d be nice to just upload it and forget about it, butโ€ฆ itโ€™s such an obscure topic that hardly anyone searches for it anyway!