“Omics” revolution during the last few decades has vastly increased the understanding of the biological processes that remained obscure in part due to the lack of quality data. Genomics, transcriptomics, epigenomics, proteomics, lipidomics, metabolomics, and microbiomics form an invaluable array of fields that contribute holistically to a global understanding of the intertwined roles of the basic constituents of life and how they comprehensively paint a picture of disease. Metabolomics, in particular, is the study of metabolites, which are the products of cellular metabolic processes (small molecules, i.e., fatty acids, amino acids, or carbohydrates, are part of metabolomics). In this chapter, it is explained how to achieve a metabolomics profiling of aqueous humor using a special isotopic carbon labeling, a novel technique that combines a tremendous effectiveness with simplicity. The very nature of this technique guarantees the exclusion of false positives, since the algorithms are based on the recognition of unique isotopic patterns.