A newly developed imaging approach that combines laser microscopy with computational analysis may make it easier to spot ovarian cancer cells that have spread to other organs, called metastasis, a study found. The new technique was described in a paper, titled "Two-photon images reveal unique texture features for label-free identification of ovarian cancer peritoneal metastases," which was published in Biomedical Optics Express. Cancer cells that have spread to distant organs are called metastases, and detecting these cells accurately and early on is critical for treatment. One way to find these cells is to look at tissue biopsies under a microscope — but this may miss small metastases. Now, researchers developed a method to better identify these cells. The method uses two-photon microscopy, which involves firing short bursts of light at a sample. Then, based on how the light reflects and refracts off parts of the sample that have different shapes and textures, computer programs can make inferences about the biology of the cells. In this use, they can determine if the cells are normal tissue or cancerous metastases. Importantly, unlike many other microscopy techniques, this method doesn't require much sample preparation before a slide is put under a microscope. There are no added chemicals used to label different cell types.