Cystic Lesions of the Orbit

Abstract

Orbital cystic lesions encompass an array of congenital and acquired conditions with diverse aetiologies, ranging from benign, asymptomatic cysts to sight-threatening infectious or malignant disease. 1,2 They account for 14% to 21% of all orbital lesions. 2 Macroscopically, cystic lesions appear as saccular, fluid-filled structures encapsulated by a clearly demarcated wall. 1 They are commonly classified according to the cellular origin or etiology. 3,4 In a 2004 review of childhood orbital lesions, Shields and Shields 5 categorized cystic lesions by cellular origin (surface epithelium-derived, teratomatous, neural, secondary, infectious, and noncystic lesions with a cystic component). Another classification system, proposed by Kaufman et al, 6 in 1998, organizes cystic lesions by etiology; that is, congenital, acquired, or secondary cysts arising from adjacent structures. This review will expand upon the latter scheme, employing the following classifications; congenital (epithelial and nonepithelial), vascular, infectious and inflammatory, neoplastic, and miscellaneous. True cysts and cyst-like lesions, that is, those which appear cystic on imaging, will be covered, with a particular focus on the radiologic characteristics seen.Congenital lesions, such as dermoid cysts and orbital teratoma, generally present in infancy or early childhood and are usually benign; those which present later in life are more likely acquired, although lesions such as deep orbital dermoids may present in adulthood. [6][7][8] Clinical features vary depending on the size, depth, and aggressiveness of the underlying lesion. Superficial cysts often present with a painless,