Fungal nail infection (Onychomycosis) is the most difficult of superficial fungal infections to treat, because most topical treatments are unable to penetrate the nail plate to reach the active infection in the nail bed (the skin under the nail). Fenestration involves drilling micro holes into the nail using specialised equipment. This then allows your foot specialist to apply an antifungal agent such as Lamisil spray directly to the infected area. Daily self treatment of topical antifungal medication is required to stop fungal spread, and the damaged nail will eventually grow out. This is a painless procedure as the nail is ‘dead’.