 Aqueous flow rate: Participants will be asked to self-administer 3 to 6 drops depending on their age of fluorescein sodium 2 topically into both eyes at 5 minute intervals on the night before the fluorophotometric scans. Fluorophotometry will be performed using a scanning ocular fluorophotometer from 9:00 am -12:00 midday. Four sets of triplicate scans will be collected at 1 hour intervals to determine the aqueous flow rate Ft. The 3 scans are done in quick succession, taking approximately 2 seconds in total to complete the set. Following each set of scans, IOP will be measured using pneumatonometry. and rebound tonometry. IOP will be recorded as the mean of a total of 12 measurements per eye: 3 measurements every hour alternating between eyes. 