A painless, swollen finger (for 20 years) Dr Anton Alexandroff, PhD, Nigel Kirkham, MD, Neena Nayak, MRCP The Lancet Volume 371, Issue 9618, (March 2008) DOI: 10.1016/S0140-6736(08)60487-0 Copyright © 2008 Elsevier Ltd Terms and Conditions
Figure Gout (A) The swollen interphalangeal joint. (B) Negatively birefringent crystals. Birefringence is double refraction, and occurs with materials that are anisotropic: they scatter light unevenly. In pseudogout, joints contain positively birefringent crystals of calcium pyrophosphate dihydrate. The Lancet 2008 371, DOI: (10.1016/S0140-6736(08)60487-0) Copyright © 2008 Elsevier Ltd Terms and Conditions