The GER was assessed by using real -
time ultrasonography (SSA - 220A ultrasonographer; Toshiba Diagnostic Equipment, Rome, Italy) according to the procedure described (6).
Additional diagnostic procedures may include electroretinography (ERG), gonioscopy, ocular
ultrasonography, tear film break - up
times, blood pressure measurements, neuro - ophthalmic testing, nasolacrimal duct cannulation and irrigation.