This brief report of a case of uric acid ureteral calculus illustrates a novel means of diagnosis, as demonstrated by the accompanying roentgenographic print.
A diagnosis of uric acid stone usually depends on the waxtipped catheter, or a visual demonstration of dilatation of the ureter and pelvis above the obstructing stone by means of a pyelogram and ureterogram. In a few instances, after the injection of collargol into the pelvis of the kidney and subsequent draining off of the collargol, an otherwise obscure calculus has become evident on Roentgen examination because of the adherence of some of the collargol to the rough surface of the calculus. In this following case, the urate stone appears on the roentgenogram as a vacuole in the dense shadow thrown by thorium injected into the ureter.
The patient, a man, aged 51, was admitted to the medical side of Bellevue Hospital, Sept. 30, 1916, and