What is the role of OCD in coma?

OCD & Coma? If one were comatose, s/he would not be awake to be obsessing or doing compulsive behaviors. Unless i'm completely missing the meaning of your question, i'd say that OCD is completely unrelated to coma.
OCD means what. Please do not use acronyms when addressing questions. Explain what you mean. By using acronyms you introduce a significant chance for confusion. I've been practicing medicine for 45 years and have no idea what you are talking about. If you mean obsessive compulsive disorder, what relevance does this have in coma? None. Or do you mean oculocerebral dystrophy? Or.....?