Radioisotope antegrade pyelography in ureterovesical obstruction

A radioisotope renal scan is commonly used for renal investigation and is especially useful in frequently encountered allergic patients for whom conventional IV pyelography could be hazardous. When retrograde pyelography is technically not feasible in such patients, radioisotope antegrade pyelography provides an effective means for diagnosing, localising and delineating the nature of ureteral obstructions. A case is described of post-operative ureterovesical obstruction with severe septic complications, requiring emergency nephrostomy. Radioisotope antegrade pyelography (nephrostography) with 99mTc-DTPA clearly demonstrated the obstruction and following ureteral reimplantation confirmed free outflow.