Question: My ob-gyn performed an exploratory laparotomy, partial left salpingectomy, left oophorectomy, right ovarian cystectomy. I billed with 58720 and 58925-51, but the insurance company only paid for 58720. What did I do wrong? Montana Subscriber Answer: You should have added modifier LT (Left side) to 58720 (Salpingo-oophorectomy, complete or partial, unilateral or bilateral (separate procedure)) and modifier RT (Right side) to 58925 (Ovarian cystectomy, unilateral or bilateral). This lets the payer know your ob-gyn performed these procedures on two different sides. The National Correct Coding Initiative (NCCI) does not bundle these codes, but notice how 58720’s descriptor does include “separate procedure.” This might have caused payer problems. Also, you should have billed 58925 first, because it has higher relative value units (RVUs) than 58720.