IONTOPHORESIS of therapeutic agents capable of ionization has been shown to give high intraocular concentrations of these substances. Since the epithelium of the excised cornea not only is virtually impermeable to electrolytes1 but also possesses a high degree of electrical resistance,2 the undamaged cornea would seem to be unsuited to the iontophoretic transfer of ions.
The appearance of a transient epithelial haze after the use of iontophoresis has been noted by several investigators.3 This is usually reported as clearing within a few hours, but in 1 case a 4 mm. nebula persisted three weeks after treatment.3a These observations considered with the finding that damage to the corneal epithelium increases its permeability to penicillin4 lead one to suspect that the reported efficacy of iontophoresis may be due to epithelial injury. Von Sallmann clearly demonstrated by in vivo experiments that the iontophoretic transfer of penicillin into and
DYSON C. INFLUENCE OF IONTOPHORESIS ON THE PERMEABILITY OF THE EXCISED CORNEA. Arch Ophthalmol. 1949;42(4):416-421. doi:10.1001/archopht.1949.00900050424007