Is there a different process other than the dye test to find the sentinel node? my passage is most likely blocked due to two previous surgeries there.

Radioisotope used: Whether sentinel node is in the groin or axilla sometimes radiolabelled isotope can be employed. If surgery blocks lymphatic route to sentinel node, the lower axillary nodes can be sampled as well as nodes in region of saphenofemoral junction.. Removal of the fat pad with nodes usually contains the sentinel node while dye or gamma scanning is more efficient.

Lymph node mapping: If a sentinel lymph node biopsy is required in an area of previous surgery, I would recommend using both lymph node mapping performed by nuclear medicine and blue dye in the operating room along with a hand held gamma probe. With both, the chance of locating a sentinel lymph node increases.