Board Thread:Questions and Answers/@comment-39718735-20200611060928/@comment-45210418-20200611222849

We can see that DIO can use his blood vessels to connect things, like how Esidisi uses them to shoot his blood. (We see Dio do this during Episode 9 of Phantom Blood, when he is a head). If he used the blood vessels to keep his brain intact even after it is bisected (considering he survived a blow to the brain from Star Platinum), he could have a chance of existing again.