Question: When the ED physician removes a benign lesion, how should I measure the excision size (the diameter of the wound)? Also, when should we measure the excision area — before or after the lesion goes to pathology?
Missouri Subscriber
Answer: When calculating lesion excision size for coding purposes, you’re selling yourself short if you just measure the lesion: for optimal return on your coding, report the total excised diameter on the claim.
First, find out the exact size of the lesion. According to CPT®, code selection is determined by measuring the greatest clinical diameter of the apparent lesion plus that margin required for complete excision (excision diameter plus the most narrow margins required equals the excised diameter).
So let’s say the ED physician treats a lesion on the patient’s left leg. The operative report indicates that the lesion was benign; the lesion was 2.6 cm at its widest point, and the ED physician also had to remove a margin of 0.3cm on either side of the lesion.
To come up with total excised diameter, add the lesion diameter (2.6) and the margin (0.3 + 0.3), and the diameter would be 3.2cm. On the claim, you would report 11404 (Excision, benign lesion including margins, except skin tag [unless listed elsewhere], trunk, arms, or legs; excised diameter 3.1 to 4.0 cm) for this encounter.
Lesions will shrink during the pathologist’s analysis, so have the physician measure and document the excision area, then send the lesion to pathology.