Can health insurance deny claim after pre-authorization

How likely is it & under what circumstances can a health insurance company deny a claim if they had pre-authorized the treatment earlier.
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Yes, its possible that a claim can be denied after a pre-authorization. But only under very specific circumstances. For example... If you have a change in coverage between the time that the service was pre-authorized and the time the service happens. If your coverage is canceled completely. (You need to be eligible for insurance coverage on the date the services are actually done.) If it is determined that your pre-authorization was fraudulent. (ex- you or your doctor submitted false information to get the approval) If the services you have done and your provider bills for don't match up with the pre-authorization. (Ex - you get pre-auth for one specific type of surgery, but you actually have something slightly different.) If you get pre-authorization for a specific doctor to do a service, but end up having a different doctor do the service without notifying the insurer in advance. Those are just some examples. Basically if you have the exact same procedure that was pre-approved and absolutely nothing has changed about the terms of your coverage on the policy, you should be fine. The problems that could arise come from either a change in your policy/coverage or a change in the procedure that was actually done.
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