Your swelling pattern—especially worsening during or after eating—can occur with a parotid salivary-duct blockage or narrowing, even if an ultrasound did not clearly show the duct. Small stones, mucus plugs, or duct strictures may be missed on routine ultrasound.
Please see an ENT/head-and-neck surgeon who manages salivary-gland disease and performs sialendoscopy. An oral and maxillofacial surgeon may also be helpful if the swelling appears to be arising from the cheek, teeth, or maxillary sinus rather than the parotid gland.
Next Steps
Useful next steps are:
Review your previous CT scan and ultrasound images—not only the written reports.
A dedicated ultrasound of the parotid gland and duct, ideally performed when symptomatic or after a sour stimulus.
If still unclear: MR sialography, contrast CT/MRI of the face/neck, or diagnostic sialendoscopy to look for narrowing or a small obstruction.
If a focal lump is seen, it may need needle sampling.
FESS/septoplasty can cause postoperative changes, but meal-related swelling warrants a focused salivary-gland assessment rather than assuming it is from the sinus surgery. Seek urgent review if you develop fever, redness, severe pain, pus in the mouth, rapid progression, eye symptoms, or facial weakness.