POAG was diagnosed based on high IOP (>21 mmHg) at the time of diagnosis, typical glaucomatous optic disc and visual field changes, and normal anterior chamber angle. In contrast, PEX glaucoma diagnosis was based on high IOP (>21 mmHg) at diagnosis and typical glaucomatous optic disc and visual field changes, plus the presence of PEX material or hyperpigmentation in the anterior chamber angle and the presence of PEX material at the pupillary margins or the anterior lens on anterior segment examination after pupil dilation. The control group consisted of healthy individuals with normal anterior and posterior segment findings and IOP less than 21 mmHg.