Dog throwing up meals 10-12 hours after eating

I have a three year old dog that I had to take for an emergency appointment his vet a week ago because he was throwing up each meal 10-12 hours after eating. This happened three meals in a row and then I immediately took him in when I noticed it wasnt stopping. It seems like his stomach had the full amount of his meal in it each time. They did an x-ray and barium study with no answers showing why he's throwing up. He was on a pill to stop the throwing up for three days after my visit and also on a ground beef and rice diet the last week with just a small amount of dog food mixed in each day and and he didn't throw up at all. Yesterday was his first day back on just dog food. Unfortunately today at 4:20 am he just threw up again. Same thing, seems like his whole meal that he ate 10 hours ago. ( This is also a new food from when was throwing up last week because he needed something with a lower cal content). He is still going poop and pee, hard to tell if he's lethargic because he's being really restricted because of his front leg issue and he's pretty miserable about that. I don't know what to do anymore to figure this out, I've also been trying to figure out why he suddenly started limping on his right leg like two weeks ago quite bad with no injury prior to either limping episode, for a year on and off he was limping on the left front and the specialist and normal vet couldn't figure out why. Now he has a CT scheduled in two weeks that I absolutely need to show something.  He's on carprofin, which he's taken the past week for that, and gabapentin that he started two days ago... Any advice on what I can do or what might be the cause of throwing up the meals? If I take him back to the vet for another apt I won't be able to afford his upcoming CT. The last throwing up apt was $530 and that pretty much wiped out my extra funds besides what I can put on credit for his CT so if there's a specific test that might help the most for figuring this out it would be so greatly appreciated. ❤️   Thank you so much, Michelle and Charlie

Hello!  Usually by 10 hours after eating I would expect a dogs' stomach to be emptying again, so it's interesting that it is still full of food to the extent that the patient is vomiting.  I wonder if this suggests that the stomach is not pushing food on down the tract as fast as required, which may be a functional neurological problem (of the nerves supplying the gut) or a muscle strength problem (reduction in peristalsis for example), and I have to admit to not being sure how well this would show on a CT scan (dog CT is still relatively specialist in the UK).  Of course I do not know your dogs' specifics, breed etc which your vet does, so they will have a better idea than me what they are searching for.  Nor do I know whether this is true vomit or regurgitation, or whether or not your vets know or have researched how likely it is that something might be found on CT - perhaps by reading papers or asking a specialist in advance, for example.  (I'm afraid that I do not know the answer off the top off my head - although the specialist might).   If this was my dog, I would be asking how well a specialist rated the chances of their finding something you could do something about on this scan?  It sounds as though, even if they find something, there would then be limited money to spend on treatment - which begs the question as to how helpful the scan will be if it shows something? It does sound however as though this could be discussed in a consultation with the right person and although it may increase the cost, it may also turn out to be worth your while.