Calculated Computed Tomography Volumes of Lacrimal Glands and Comparison to Clinical Findings in Patients With Thyroid Eye Disease

Abstract

To describe the range of lacrimal gland volumes on CT in Caucasian patients with thyroid eye disease (TED) and to correlate with clinical findings. With institutional review board approval, 125 orbital CT scans for TED were reviewed. OsiriX software was used to calculate the volume of the lacrimal gland. Comparison of the volumes was made with previously published results of the normal population. Patient race, gender, smoking status, diplopia, tearing, exophthalmometry, superficial punctate keratitis (SPK), lagophthalmos, restriction in motility, and VISA score were collected. The mean volume of the lacrimal gland in patients with TED was 0.890 cm in right orbits (standard deviation [SD] 0.348), 0.851 cm in left orbits (SD 0.350), with no significant difference between right and left (p = 0.311). The mean volume was 0.811 cm in right male orbits (SD 0.386) and 0.911 cm in right female orbits (SD 0.335), with no significant difference between men and women (p = 0.774). These findings were confirmed in an analysis of left orbits. The volume of right and left orbits correlated well (r = 0.777, p < 0.0001). The lacrimal gland volume in patients with TED was greater compared with the normal population using a 2-sample t test (p < 0.0001). Exophthalmometry (right: r = 0.225, p = 0.0115; left: r = 0.267, p = 0.0026) and subjective tearing (right: r = 0.226, p = 0.0138; left: r = 0.197, p = 0.0322) correlated with lacrimal gland volume. This study is the first to report the volume of the lacrimal gland calculated on CT scan for patients with TED. The lacrimal gland is larger in patients with TED and correlates with subjective tearing and exophthalmometry.