Comparison of lacrimal gland dimensions and volume in unilateral Ahmed glaucoma valve versus trabeculectomy

Purpose To evaluate radiographic lacrimal gland (LG) volume and dimensions in Ahmed glaucoma valve (AGV)- versus trabeculectomy-treated eyes and contralateral non-treated eyes. Methods In this retrospective cohort study, 1616 medical records acquired between 2010 and 2020 were examined. In AGV-treated (group 1) eyes, there were 19 patients with records sufficient for radiological LG evaluation, and in trabeculectomy-treated (group 2) eyes, there were 18. The hospital workstation software was used to assess high-resolution computed tomography (HRCT) scans conducted under standard protocol using a 128 SL Optima CT 660 scanner. The software (Vitrea™) was used to perform semi-quantitative volumetric measurements. LG dimensions were obtained in the axial and reformatted coronal planes on each side, and four measures were generated using the widest LG tip-to-tip diameters in two planes: coronal length, coronal width (CW), axial length (AL), and axial width. Results The time interval between surgery and HRCT imaging was 50.97 ± 26.25 months. Group 1 had significantly lower LG volume than group 2 (594.11 ± 259.45 vs. 933.67 ± 294.09 mm 3 , P = 0.001). When compared to non-treated eyes, AGV-treated eyes had lower LG volume ( P = 0.065) while trabeculectomy-treated eyes had higher LG volume ( P = 0.031). Further, group 1 had decreased length and width in both the axial and coronal planes as compared to group 2, with AL and CW being significantly different ( P