Silent sinus syndrome without opacification of ipsilateral maxillary sinus

Silent sinus syndrome (SSS) is a rare disease characterized by spontaneous enophthalmos and hypoglobus secondary to collapse of the orbital floor in patients with asymptomatic maxillary sinusitis. Radiographic findings include ipsilateral maxillary sinus opacification, lateralization of the uncinate and middle turbinate, and infundibular occlusion. We present a case series of three patients with clinical and radiographic evidence of SSS but without maxillary sinus opacification. Although uncommon, an aerated maxillary sinus in patients with unexplained enophthalmos, hypoglobus, and maxillary atelectasis should not exclude the diagnosis of SSS. Laryngoscope, 128:2004-2007, 2018.