Predicting Urinary Stone Composition Using X-Ray Coherent Scatter: A Novel Technique With Potential Clinical Applications

Purpose: Coherent scatter properties depend on the molecular structure of the scattering medium and measured scatter patterns are often characteristic of a chemical species. We explored the usefulness of coherent scatter analysis as a basis for identifying urinary calculus composition.Materials and Methods: A laboratory system for collecting coherent scatter signals from biological specimens was developed. This technique uses a diagnostic x-ray tube and image intensifier, and measures coherent scatter from intact renal stones. The coherent scatter signatures of 6 common stone components (calcium oxalate monohydrate, calcium phosphate, calcium phosphate dihydrate, cystine, magnesium ammonium phosphate and uric acid) were acquired from pure chemical samples and stones identified by infrared spectroscopy as having a uniform composition. In addition, a sample of calculus identified as containing only calcium oxalate dihydrate was examined. The same fragmented stone samples analyzed by infrared spectroscopy we...