Criteria for the design of tissue-mimicking phantoms for the standardization of biophotonic instrumentation

Abstract

The reliability and reproducibility of experimental results are crucial in the development and regulatory approval of medical technologies, yet represent a challenge for biophotonic instrumentation due to a lack of accepted standards and phantoms suitable for successful technical validations. Here, we discuss the general design considerations for the preparation of tissue-mimicking biophotonic phantoms and then critically review the existing literature on phantom materials and fabrication across the field in light of these criteria and of recent developments at the state-of-the-art. We then focus on three representative examples of biophotonic standardisation related to different modalities, presented in order of their relative maturity: diffuse optical imaging and spectroscopy, fluorescence guided surgery, and photoacoustic imaging. Finally, we provide a perspective on future phantom development and the unmet needs of the biophotonic field, identifying a set of criteria, termed the “4Cs”, for biophotonic standardisation which highlight the need for characterisation, collaboration, communication and commitment to maximise the achievements of ongoing standardisation efforts.