ghost is very much incorrect in this situation, you have only 700 odd chips left with around 1400 already in the pot and you have top pair top kick against a guy who sounds fairly maniacal and bad in general, thus its an insta all in. The only mistake you made in the hand was not shoving over his preflop reraise in th first place. Basically in this hand you were destined to go broke looking at the flop and the fact dean was willing to get it all in pre with his 88.