Ob-Gyn Coding Alert

Question: I have a tough case that I need help with. The physician suspected a recurrence of a patient’s endometriosis causing a fallopian tube occlusion. The endo was treated by another doctor with cautery about 18 months ago, but the recurrence rate of endo after cautery is quite high, and the patient’s preoperative symptoms were consistent with endo. A previous doctor performed an HSG 6 months ago. X-rays from that HSG show a right proximal tubal occlusion, with no dye spillage at the distal end. The left tube had complete but patchy dye flow on the HSG 6 months ago, but it was not a formal tubal occlusion like the right tube appeared to have.

To address the previously investigated tubes, the physician performed 58345,50 (HSG with Bilateral tubal catheterization). The physician noted regular tubal pressures, but incomplete dye spillage on both tubes, which necessitated the catheterizations. On the left tube, the physician was only able to insert the metal wire about 1/3 down the tube; however, dye spilled freely down the left tube after the wire was removed, so the final Dx on the left tube was patency, and although an occlusion may have prevented the guide wire from being inserted all the way down the tube, this is not totally certain, and nothing obstructed the dye the second time.

On the right tube, the physician was able to insert the metal wire down the entire length of the tube-no tubal occlusion of any sort was discovered. Dye spilled freely down the right tube after the wire was removed, so the final Dx on the right tube was patency, as well, so final Dx was Bilateral patent tubes.

Should this be billed as N97.8 only, because that is what the physician may have treated? Or should I report Z31.41 only, because a physical occlusion was never formally discovered and documented as such in the Operative Note? Or, would Z31.41 as primary Dx and N97.8 secondary Dx be the “best of both worlds” here? I think that coding any of the N80 codes (for endo) is incorrect, because endo was not formally discovered, and you’re supposed to code what you find. Although we may discover endo as the cause of the just-treated apparent occlusions in a future laparoscopy, we do not have definitive evidence of this being the case yet, so an endo Dx needs to wait for another day, or in this case, another claim. Which is correct?

Codify Subscriber

Answer: He was doing the procedure to test for tubal patency, and the only reason to do that is because she was having problems getting pregnant. As this was a diagnostic procedure, you should go with Z31.41 (Encounter for fertility testing). You would not use a N97 code (Female infertility …) unless you have confirmed she is infertile.