The silent sinus syndrome consists of painless facial asymmetry characterized by
unilateral enophthalmos. Reabsorbed bone with displacement of the orbital floor
is a constant finding. It is secondary to chronic maxillary sinus atelectasis.
The onset of symptoms is usually slightly progressive but can be brisk due to
sudden collapse of the orbital thin bony floor. The diagnosis is suggested by
clinical findings including endonasal endoscopic examination and confirmed on the
basis of computed tomography and magnetic resonance imaging. The restitution
treatment of the silent sinus syndrome involves functional endoscopic sinus
surgery and plastic reconstruction of the floor of the orbit via
transconjunctival approach; an additional vestibular incision may be necessary to
treat the malar region. Four cases of this rare and therefore relatively unknown
disease are fully discussed