Fast computation of Mom matrix elements

i have found some papers on how to computate the elements of mom matrix elements fast which are used to analyze the microstrip antennas.But all of them do not consider the attachment currents at the junction of probe and patch, and not include the probe surface currents either. if i take these currents into account, are there good schemes to computate the Z matrix fast? can anybody help me?

it is urgent

thanks a lot