The application and use of calibration strips in quantitative digital imaging

Digital Macro Imaging in modern medicine has the potential to significantly improve patient outcomes if accurate data can be extracted efficiently and valid meta data can be added to a clinical database. At the present time much data from standard photographic images is not quantitative and is therefore of limited use. Our approach is to develop simple tools and methodologies that make it possible to internally calibrate images and our subsequent goal is to develop an online analytical tool set that will import, display, calibrate, save and share images and data in a clinically secure setting. In this paper we describe the process of developing a range of calibration strips that can be used by clinical staff with little or no experience of photography in most environments including, the clinic, the ward, the GP surgery or the home. The imaging strips provide an internal calibration standard that help ensure the wound, lesion, or dermatology is properly framed for downstream linear, colour and shape measurements. Once photographed, the calibrated imaged can then be used in a quantitative way for longitudinal or comparative analysis. We believe this approach has the potential to benefit benefit to the clinical photography department, the clinician, the researcher, clinical trials specialist and, most importantly, the patient.