Which measurement is used to determine the size of a lesion?

• A. Measuring with a small clear ruler in centimeters
• B. Estimating size by sight
• C. Using a ruler marked in inches
• D. Weighing the lesion

Answer: (A)

Accurate lesion size is documented using a small clear ruler marked in centimeters to capture the true dimensions. This method provides a precise, reproducible measurement that can be reliably recorded and tracked over time, which is essential for monitoring growth or response to treatment. A clear ruler helps you align with the lesion’s edges and reduce parallax error, giving you the longest diameter (and, if needed, the perpendicular width). Estimating by sight is subjective and varies between clinicians, and using inches is less consistent in many medical records that favor metric documentation. Weighing the lesion doesn’t measure its size at all.