Tracy, this question came up recently on this forum, and unfortunately I think you're going to have a rough time of it. The good news is that every health insurer is required to have some kind of appeals system by federal law, so if you contact your insurer they will tell you how to file an appeal. Further good news is that, in CA, you have the right to external appeal to the DMHC (dept of managed health care) after you exhaust your internal appeals.
Now the bad news - it is doubtful that the DMHC will overturn your health plan's denial for the VSG because it is still considered investigational. There is no knowledge of longterm results with this operation because it has been done as a "stand alone" operation for only a few years. Moreover, the 3-5 year results that are just becomming available don't look better than for RNY, so it is doubtful that the DMHC will force your insurer to cover something that isn't better than what they offer. A further problem - for people with higher bmi's, the results with vsg even short term are not looking good at all.
There will be some people who are very successful with vsg. But when you look at large groups of people, which is what insurers and reviewers do, the overall results are not great.
However, there is another alternative for you to consider. Have you looked at all at the duodenal switch? The vsg is the top half, so to speak, of the DS. The DS has been around since 1988 and there is documentation in the medical literature of the excellent results in excess weight loss, maintaining that weight loss, and resolution of comorbidities - all superior to rny. It has the best rate of resolution of type 2 diabetes of any wls - 98%. Like the vsg, it would allow you to take NSAIDs, to drink liquids with your meals, and eat a more varied diet than rny or lap band. And no dumping. Also, even if your insurer doesn't cover it, the DMHC review almost always overturns denials in favor of the DS.
Come on over to the DS forum and learn more about this operation. And if you want to read some articles about it for yourself, send me a pm.
Larra