Dog paralyzed in RIGHT side legs. Blood clot, tumor or viral/bacterial infection?

[Krendog]

Monday our 12yr old lab was running around fine outside in the garden (we live in the country) and by Thursday he has become bedridden and unable to move his right side limbs. We took him to the vet and they said it probably is a tumor or blood clot that’s preventing the blood flow to the spine. I do not recall any tests being administered but I don’t want to euthanize my best buddy if it’s just a viral/bacterial infection that could be causing this as well. We won’t have a CT scan done or anything because they’re so expensive but how could they give this sort of a diagnosis? Also, I’m not an expert but it just seems very odd to me that the onset of symptoms would progress at such a rapid rate for it to be a tumor or blood clot. In the span of 3-4 days he went from fine to completely immobile. Any thoughts? Idk if it matters but he can still wag his tail.

[Krendog]

So we had him taking prednisone 50mg every 12 hrs for 3-4 days and it just only helped his mobility throughout his body a little bit but didn’t fix the paralysis in his legs and in just 5-6 days you could see he had already lost so much muscle. It was frustrating him so much to not be able to stand or even get up. It was the cutest thing; We put him on a little 2inch thick foam mat so we could transport him around the house (he weighed 104lbs). We took him for one last car ride (those were his favorite), we gave him some steak and we spent the last couple days loving him up. He had his mind but just didn’t have the body. Yesterday we said our goodbyes, made sure he knew how much we loved him and always will, bawled our eyes out (still continuing the bawling as I write this) and we let him go. My heart breaks for all of you that have to say goodbye to your little members of the family.

[Krendog]

Anyone have any ideas? He's been on the prednisone for 2 days now. Taking 50mg every 12 hours and we've seen slight improvements but he still doesn't seem to be able to move his right legs. We've seen him flex them straight out and he can bare weight on them but still can get up or walk. I've found that the back of his neck approx. 1 inch below the base of his cranium is tender and and if I travel down another 4 inches and massage, he also responds to that pressure. He doesn't whine or yelp, he just gets ancy and wiggly as if it's tender that I press on it. Is this probably more consistent with a lesion that is blocking the nerves to his right legs? Why aren't his left legs affected at all? Is this paralysis probably permanent?

[specialmom]

Ahh, your poor pup!  Did they not offer any remedy such as medication?  Even pain relieving medication for your dog?  I would get a second opinion.  

[Krendog]

Well I wasn’t there in person to witness what was all said and done. They did confirm that he had no sense of feeling in his right side. As of 2 hours ago we thought we were going to be putting him down but my engineering troubleshooting wouldn’t have it. I’ve been researching forums and discussion boards and we were able to try him on a prednisone pack. I’m hoping the prednisone will reduce any inflammation caused by tumor, blood clot, etc. that might be causing any reduced blood flow to his spine which in turn has created the paralysis. We’re not going down without a fight! Will keep you posted with any progress.