Ultra-thin three-wavelength SFDI endoscope for early cancer detection

There is a clinical need for a cost-effective imaging device capable of detecting pancreatic cancer at early stages [1]. Here, we present a modified design for an ultra-thin (3 mm diameter) endoscope prototype that uses Spatial Frequency Domain Imaging (SFDI) at three wavelengths (450, 515 and 660nm) to achieve enhanced image contrast [2]. Spatial Frequency Domain Imaging (SFDI) is a low-cost optical imaging technique that works by projecting fringes over a sample and measuring the diffuse reflectance, from which optical properties that serve as cancer indicators can be calculated: the absorption and reduced scattering coefficients [3]. To prepare the prototype for clinical applications, we incorporate a Spatial Light Modulator (SLM) (60 Hz frame rate) to automate pattern projection and explore the use of our shortest wavelength (450 nm) to achieve enhanced contrast of blood capillaries [4]. We validate the system on 16 calibrated tissue-mimicking phantoms, showing the potential of the prototype to produce near real-time measurements of cancer indicators. DOI: [1] 10.3390/diagnostics10110869 [2] 10.1117/1.JBO.29.2.026002 [3] 10.1117/1.JBO.24.7.071613 [4] 10.1117/1.1695563