It is not surprising that small fragments of bone, cartilage or lining tissue may remain in the area of surgery after a rhinoplasty. Most of the time these do not cause a problem. Occasionally fragments of mucous or lining tissue are implanted deeper in the nose and can cause a small cyst to develop. These are called mucous cysts and are filled with a liquid mucous secretion.
These cysts can occur anywhere in the nose but are most common on the bridge and, if the nose was broken, along the fracture line. The swelling gradually increases in size and can take many months or even years to be noticed. They may be associated with some redness or inflammation.
The treatment is to remove the cyst surgically usually through an incision inside the nose.