Stamp LK, et al. - Investigators assessed the data to analyze the clinical efficacy of multi-energy spectral photon-counting CT in crystal arthritis. They noticed bone erosions with overhanging edges in plain X-ray of the gouty finger. They found monosodium urate (MSU) crystal deposits while inspecting with dual-energy CT (DECT) and multi-energy spectral photon-counting CT (SPCCT). They suggested multi-energy SPCCT in the diagnosis of crystal arthropathies as it precisely detected, recognized and quantified calcium pyrophosphate (CPP) within an osteoarthritic meniscus, and differentiated them from hydroxyapatite (HA) crystal deposits.