Orbital venous anomalies

The purpose of the study is to establish the natural history, probable nature, and optimal treatment of lesions within the orbit described previously as lymphangiomas or orbital varices.

The clinical and radiologic records of 158 patients with these lesions were reviewed. Of these, 91 had surgery, and histologic specimens from 57 were re-examined.

Most patients were infants or children with a dark blue swelling in the superomedial part of the orbit, orbital hemorrhage, or proptosis. Computed tomography showed smooth, contoured lesions denser than brain extending posteriorly. Half enlarged with the Valsalva maneuver, 31% contained phleboliths. Surgery was performed in 91 patients, mainly for cosmesis. Excised tissue included endothelium-lined channels containing blood in the orbit and clear fluid in many superficial specimens.

The behavior of these lesions and their prevalence in infancy and childhood favor a hamartoma. The authors observed a seamless range of clinical features that they could not subdivide, particularly in relation to any connection with the orbital veins. Many bleed and enlarge permanently and need excision, but surgery is difficult and management should be as conservative as possible. The origin of these lesions cannot be determined by histopathologic analysis, although the authors have evidence of venous features in the orbit and lymphatic features more superficially. The authors' clinical findings support a venous origin. Two-thirds have either a free venous connection or phleboliths. Their distribution corresponds with that of the normal orbital veins, and at surgery they derive from or replace those veins. "Orbital venous anomaly" is the most accurate term for their description.