Table 4-8.

Radiopacity of Cystic Calculi on Plain Abdominal Radiographs

Calculus Composition	Density
Calcium oxalate	Radiopaque
Calcium carbonate	Radiopaque
Triple phosphate	Radiopaque—small calculi may be nonradiopaque
Cystine	Variable density—may have radiopaque stippling
Uric acid and urates	Nonradiopaque
Xanthine	Nonradiopaque
Matrix concretions	Nonradiopaque

From Park RD: Radiology of the urinary bladder and urethra. In O'Brien TR, editor: Radiographic diagnosis of abdominal disorders in the dog and cat, Philadelphia, 1978, WB Saunders.