Pathological expansion of paranasal sinuses is a rare diagnosis made radiographically given the pathognomonic CT appearance. The expected findings on CT are an air-filled expansion of a sinus beyond the normal anatomical limits with or without associated cortical bone thinning. Although nomenclature of this condition is complicated, a simplified approach of naming all the lesions as air cysts is preferred because management is dictated by symptomatology.

From the manuscript

Maxillary Air Cyst

Abstract
Pathologic dilatation of the maxillary sinus by air is a rare condition with unclear etiology. We present a case of a 17 year old male with a maxillary air cyst diagnosed by computed tomography. The CT demonstrated air-filled expansion of the maxillary sinus beyond the normal anatomical limits with associated cortical bone thinning. The case report highlights the pathognomonic computed tomography findings of this rare entity and discusses the perplexing nomenclature, proposed etiologies and various treatment options.