Researchers are developing an endoscopic imaging tool that could aid in the diagnosis of cancer without the need for tissue staining.

This tool could enable quick and accurate diagnosis in vivo, in part because staining for histologic analysis by a pathologist would not be necessary. Early diagnosis of cancer typically results in better prognosis.

This handheld fiber optic probe records simultaneous nonlinear imaging modalities using an ultrafast LASER. The probe is 8 mm in diameter.

In addition to aiding endoscopic diagnoses, this probe, which functions as a miniaturized microscope, could be used in surgery.

The kinds of images the probe can simultaneously record are coherent anti-Stokes Raman scattering (CARS), second harmonic generation (SHG), and 2-photon excited auto-fluorescence (TPEF).

The probe does not require moving parts or electric power.

Researchers showed that the probe could acquire CARS, SHG, and TPEF of healthy human skin samples at 2048 by 2048 pixels in an area of 300 by 300 micros, which is a sufficient resolution for the successful identification of tumor borders.

Researchers next plan on testing the probe in animal models.


1. Lukić A, Dochow S, Bae H, et al. Endoscopic fiber probe for nonlinear spectroscopic imaging. Optica. 2017;4(5):496-501.