A prospective randomized controlled trial was conducted at Al Watany Eye Hospital in Egypt. Patients with refractory primary or secondary childhood glaucoma who glaucoma specialist has decided to perform a tube implant to control their intraocular pressure are randomized to receive either Paul or Ahmed glaucoma drainage devices.
Patients will be followed up for at least one year during which the following data are collected.
Age, sex, laterality, preoperative and postoperative intraocular pressure and glaucoma medications at 1,3,6, 9, and 12 months visits. Any intraoperative or postoperative complications will be recorded
