fast axonal transport is in the range of few millimeters per hour moreover the highest brimonidine auc in the neuronal tissues was found in the corpus callosum table 2 177 higher than in the right optic nerve p lt 0 01 118 higher than in the left optic nerve p lt 0 01 123 higher than in the right optic tract p lt 0 05 and 111 higher than in the left optic tract p lt 0 10 despite the fact that there are no direct connections between the optic tracts and the corpus callosum in conclusion our data provide the first case of good cns availability after ocular application of conventional ophthalmic therapeutic agent through non systemic routes it is highly likely that the pathway of drug delivery through the cns is different depending on the particular type of compound that is being administered thus while further experimentation is needed the results indicate that ocular dosing of conventional ophthalmic therapeutics may be useful to achieve good drug availability in the cns it will be understood by those of ordinary skill in the art that the same can be performed with a wide range of therapeutic agents and conditions without affecting the scope of the invention or any embodiment thereof accordingly the.