Master-slave enhanced optical coherence microscopy for real-time optical biopsy imaging

Diagnosing skin cancer, such as basal cell carcinoma, requires a biopsy, which is a time-consuming and expensive process. Therefore, it is essential to explore alternative diagnostic methods that are both more efficient and effective. We developed a handheld optical coherence microscopy (OCM) imaging device to achieve high-resolution optical biopsies in real-time. The instrument uses a variable focus liquid lens that allows fast shifting of the focus inside the sample, resulting in high-resolution lateral images throughout an extended axial imaging range. Our instrument can produce images with an axial resolution of approximately 5 mu m, currently limited by the light source employed, and better than 2 mu m transversal resolution images. The acquisition, data processing, and display of the 3D volumes are performed in real time, primarily enabled by the Master-Slave approach employed to produce the optical biopsies. The acquisition rate of the current camera used in the spectrometer was limited to 50 kHz. Our benchmarking shows that the real-time operation of the instrument can be sustained even at over 250 kHz solely by utilizing the computing power of the CPU, with no need to employ graphic cards or FPGAs. The instrument's capability is showcased through images featuring various samples, such as an IR card and skin.