You can try systemic (oral) decongestants and also antibiotics if there is a chance this is acute ie a short term issue. But if the CT does not improve you will need functional endoscopic sinus surgery (FESS). This takes 30 minutes if the issue is not more widespread, and you will be out of hospital in a few hours. It is very safe and should be curative. Just make sure you are referred to an ENT surgeon who is a rhinologist and specialises in this as opposed to a generalist. Asking how many they do each week is a good question - the answer should be at least three
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