I was recently reading Christof Koch's The Quest for Consciousness, and several times he mentioned how important some patients with sad and terrible brain injuries were for the understanding of the working of the brain.
It made me wonder how brain researchers as Koch and others find such patients. I expect that only a small number happen to see an expert-brain researcher who understands that this patient could be important for brain research, especially for such people in less developed countries.
More generally, I wonder the same for patients with very rare injuries or diseases, which could potentially be significant for medicin- and biology-research:
Is there a global database for patients with very rare deseases or injuries, making it possible for medical experts in the field to find them?
Even if the expert can not help the individual person, I imagine that such patients could be very important for future understanding/curing of the injury/disease. I hope to get some literature references or suggestion.