trying to identify a certain scrolling shooter game, HELP!

I've searching the internet for days now. Downloading roms, looking at screens shots left and right trying to figure out what scrolling shooter I have such a fond memory of. What I can tell you is that from the ones I have seen, I am fairly convinced it is one of the "Raiden" games, but I am not positive. I was able to download the rom for the first Raiden game however to my disappointment that was not it. I would know the game if I played it for sure. The only thing I can tell you for sure is that on the last level a giant dragon swallows you up into a volcano. Then the last boss is a giant dragon head (I believe). I know that is not very much info at all, but if anyone knows or maybe even think they know which game I am talking about please help me out. Thanks