It has been suggested that determing whether
marijuana could be effective as a glaucoma
medication would be a long process.

It seems to me that it would not be all that
difficult.  The first step would be to determine
whether oral dosing lowers IOP.

If oral dosing reduces IOP, then marijuana could then
soaked in various solvents and solutions.  If any of
these lowered IOP with oral dosing, then it would
seem natural that direct application to the eye of these
solutions should also lower IOP.