SAN DIEGO – Color coding reference marks on a specimen and a Mohs map preserves orientation, no matter what happens on the way to the microscope, according to Dr. Howard Steinman.
Reference marks, he explained, are small nicks made with a scalpel, sutures, or staples that serve as extensions of imaginary reference lines extending across the wound.
To distinguish them, he said he designates a 12 o’clock position at the top of the field, makes a double nick, and inks it blue, since that’s the color of the sky.
At the 6 o’clock position, he makes a single nick and marks it green, for the earth.
A third and fourth color can be designated for the 3 and 9 o’clock positions for further clarity, suggested Dr. Steinman, director of dermatologic and skin cancer surgery at Scott and White Healthcare in Temple, Tex.
Some surgeons mark the center yellow.
One day, when you least expect it, "your specimen will end up on the floor," he predicted. "This will happen to you ... [and you’ll say], thank God for the double nick."
With the ink as a guide, it will become clear to you, a technician, or a pathologist which way is up on the specimen, he said at the meeting sponsored by the American Society for Mohs Surgery.
When using green ink, remember that it’s a vital dye and can stain counters and other surfaces, noted Dr. Steinman.
"Mark before excising the specimen, because the specimen is going to rotate and contract," he said.
Dr. Steinman said he also color codes important histologic features on the Mohs map, which functions as a pathology report, medical record, and medicolegal document.
"Mark the tumor in red and everything else in black," specifically labeling all nontumor findings such as dense inflammation, incomplete margins, scars, or unrelated tumors.
Dr. Edward Yob, a dermatologic surgeon in private practice in Tulsa, Okla., said he color codes his slides as well.
"If it’s the fourth stage, it’s going to be pink," he said. Consistency is key.
Dr. Steinman said the Mohs map, with its legend and color coding, will serve as an essential document for later reference.
"Without the human, without the slides, 15 or 16 years later I can tell you exactly what I did and why," he said.
Dr. Steinman and Dr. Yob said they had no relevant financial disclosures.