Calcium Oxalate Crystals Within Ocular Tissues

Abstract
For a number of years, pathologists at the Armed Forces Institute of Pathology had recognized nonstaining anisotropic crystalline deposits within certain ocular tissues and had recorded the lesions in which they occurred under the tentative heading of "protein crystals" in the Registry of Ophthalmic Pathology. The chemical nature of the crystals, however, remained unknown. We became curious about them early in 1954, when the studies to be reported herein were initiated. A new histochemical procedure devised by Johnson1 furnished strong presumptive evidence that they contained calcium oxalate. The occurrence of these deposits was recognized in two main types of cases, one of which was phacolytic glaucoma. Hence, brief mention was made of their presence in the sclerotic nuclei of Morgagnian cataracts in the paper on phacolytic glaucoma by Flocks, Littwin, and Zimmerman.2 Independently, and without knowledge of our interest in these crystals, Dr. David G. Cogan and his