Pure cystine and urate calculi can be clearly visible using survey digital radiography.

Cystine and urate calculi are considered nonradiopaque to faintly radiopaque. Two canine cases in which these types of calculi are radiopaque and clearly apparent in vivo on survey digital radiography are described. The densities of cystine and urate calculi, as determined in vitro with computed tomography, are compared to other pure calculi and mixed or compound calculi to further explore the relative attenuation characteristics. Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.