The present invention relates to methods for treating microbial infections on the surfaces of an implant or other surfaces near an implant in a patient. In particular, the methods are useful for treating biofilm infections. The methods include the use of minimally invasive techniques, including the use of ultra sound for facilitating the detection of biofilm infections on the implant or other surface of a patient and destroying the infection by administering an anthocyanin or an anthocyanidin or metabolite thereof. In particular, the administration of protocatechuic acid (PCA) or 2,4,6 trihydroxybenzaldehyde (2,4,6 THBA) for the treatment of an infected implant or other surface of a patient is described herein.