What modifier to use?

Our OB/GYN doctor was asked to consult during a surgery by another physician in another practice. The patient was already opened up and found to have a right ovarian lesion, so our GYN doctor performed a right salpingo-oophorectomy (58940) only and then the other surgeon continued on with other surgery on the abdomen. Can I add modifier 62 to the CPT® of 58940 even though there were two different procedures going on? Also is this considered a reduced surgery, since our doctor did not open up the patient?

Thanks for assistance in this coding matter.

re: What modifier to use?

This is not co-surgery (same procedure). Modifier-52 is used to describe circumstances in which services provided were reduced in comparison to the full description of the service.