Also, why did they put you on prednisone? What did the doctors tell you as the diagnosis for the head pain? Is there an underlying condition involved?
Ice packs can help migraine pain... so if you find this helpful, yes it is wise, it won't hurt you at all... so, unless it makes your own pain worse for some reason (different things can aggravate different people's pain differently... it's very individual), using an icepack is not an unwise thing to do. If it helps, it's actually a very wise thing to do! I use icepacks when I have migraines all the time! :)
Vicodin is not a good drug to use if you have migraines at all!!! It is a very bad drug to use because it has acetaminophen in it and acetaminophen can actually cause rebound migraine pain... so vicodin can actually make your migraine pain much worse... not better. The dilaudid, also called hydromorphone, is a MUCH better medication to use because it is a pure opiate, it doesn't have any sort of medication in it that will make your migraines worse. I use hydromorphone and it is the only medication on the market that will Completely take my migraine pain away... BUT! For some people, like yourself, opiates do NOT work on their migraine pain... if opiates do NOT work for you, then I do not suggest that you continue taking them... if they do work, then they are life-saving miracle medications that patients should not ever worry about taking what so ever, but, if they do NOT work, then patients should not continue to take them because if they Don't work then it is highly possible to develop dependency issues quickly when using such medications, or other nasty side-effects... and the last thing you need is to deal with is dependency on an opiate or opiate related side-effects in addition to your migraines. And... hydropmorphone, in my opinion, is one of the BEST pain killers on the market in the opiate class of pain killers... so, if it is not working for you... those types of pain killers probably won't work for you... there ARE even stronger pure opiates on the market, but, these are usually only prescribed to patients who are actually dying of cancer or AIDS, or patients who have untreatable constant neuropathy who do not respond to other opiates... as such opiates come with a bunch of other side-effects and stuff... so, it really comes down to, how much the quality of life will be improved vs. all of the side-effects that the patient will have to deal with.
Now, something you didn't mention in the message was actual acute migraine medication... have you tried that for these pains... since you called them migraines? Migraine medication is called triptans. I suggest zomig nasal spray... or maxalt quick dissolve wafers. Your case sounds severe, so, maybe also sumatriptan by injection (this is what they tend to prescribe when all other triptans don't seem to work... as its what they give in the hospital) would be appropriate. Triptans are different from pain killers as they actually work to interrupt the physiology of the migraine to stop the migraine from happening. So, if you aren't using triptans, I would really suggest getting a prescription for triptans from your doctor and using them as soon as your feel those sharp shooting pains... because they might completely stop the problem entirely.
Also, if the topamax isn't working for you, you might want to consider trying a different daily treatment. How long have you been taking the topamax? If you have given it at least a 3 month trial... it might be time to switch to something else. There are three classes of daily meds: anticonvulsants, antidepressants and beta blockers. You are currently taking an anticonvulsant. You could try a different anticonvulsant such as valproic acid (as long as you are not trying to get pregnant). You could also try the ntidepressant called amitriptyline as it is used to treat migraines. Or, you could try one of the beta blockers used to treat migraines... I currently take Nadolol as an example (I also take topamax too).
If none of the daily medications work for you, you could try something like botox. It is used to treat migraines. Surgery is another option... although these days, botox is used instead of surgery... and it is safer and easier and you can walk out of your doctors office on the same day after you get it done.
You could also try taking 400mg of B2, 400mg of magnesium and 300mg of CoQ10 daily. These vitamins and minerals have all been shown effective at reducing the number of migraines and severity of migraines in patients with migraines in scientific clinical trials... double blind placebo trials, etc. You can ask your neurologist about it. You can pick one of these to give a try for 3 months... and then try another one of them... or you can give them all a shot at once. It just depends on if you can afford to try them all at once or if you don't mind taking that many pills in the morning. I personally tried the magnesium first, then the B2 and now I am trying the CoQ10. I still take the B2 daily too.