A method is described for optimizing ungual treatment. The method can include (a) providing a nail having at least two spaced apart holes formed from a surface thereof and extending into the nail, and (b) topically applying a radiolabeled pharmaceutical composition to the nail. At least a portion of the composition is received in the at least two holes. The method also includes (c) sectioning a portion of the nail proximate the at least two holes into a plurality of sections, (d) determining, for each of the plurality of sections, a concentration of radioactivity in the section as a function of position with respect to the at least two holes, and (e) optimizing a spacing between the at least two holes based at least partially on the determinations in step (d). A method of ungual treatment using the optimized spacing is also described.
