Diaphragmatic plication

I have Phrenic Nerve Palsy and an elevated right hemidiaphragm.  An extensive array of hospital checks/tests have ruled out other physical problems/contributors (a solid CPEX; other analytical tests, and confirmed paralysis on a sniff test).  My pulminologist has now referred me to a cardiothoracic surgeon for a possible diaphragmatic plication.  In layman's terms what does this procedure entail, and what are the expected benefits from the procedure.  Thank you.