Raman hyperspectral imaging detects novel and combinations of crystals in synovial fluids of patients with a swollen joint

The identification of synovial crystals is important for diagnosing rheumatic diseases. Currently, rheumatologists worldwide use compensated polarized light microscopy (CPLM) crystal identification, but this technique flawed. Raman spectroscopy might offer an objective, accurate alternative. We have tested hyperspectral imaging on fluid samples 28 patients with swollen joints, measuring 5–10 in each these. Reference spectra were measured using patient material, synthetic compounds, and oxalate kidney stones. Additionally, RRUFF PANGAEA databases used to identify spectra. identified the classical pathological monosodium urate gout calcium pyrophosphate deposition disease (CPPD). Hydroxyapatite, lipid spherules, monohydrate also been observed had previously fluids. Other crystals, which not CPLM, as well: calcite, aragonite, anatase, rutile, thenardite, dolomite, a carotenoid. In addition, we found combinations 13 out patients. propose that large variation detectable from small population number per has significant ramifications diagnosis CPPD. Further studies are required learn clinical significance these human arthritis.