RT Book, Section A1 Sullivan, John H. A2 Riordan-Eva, Paul A2 Cunningham, Emmett T. SR Print(0) ID 55783581 T1 Chapter 13. Orbit T2 Vaughan & Asbury's General Ophthalmology, 18e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-163420-5 LK accessmedicine.mhmedical.com/content.aspx?aid=55783581 RD 2024/03/28 AB Orbital disease usually arises within the orbit or by spread from adjacent structures, particularly the paranasal sinuses. The etiology may be inflammatory, due to infection; neoplastic, either benign or malignant and arising from bone, muscle, nerve, blood vessels, or connective tissue; or due to vascular anomalies, including arteriovenous malformations and arterial fistulas. Orbital lesions may also be due to metastatic tumors. Thus, orbital disease may be due to serious and sometimes life-threatening entities.