A 52-year-old man presents with right-sided flank pain for three hours. The pain was sudden in onset, has been constant, and is described as 10/10 in intensity, with a decrease to 8/10 after the administration of NSAIDs and morphine. He also experienced two episodes of vomiting. There is no history of chest pain, dyspnea, fever, or bowel/bladder dysfunction. His medical and surgical histories are unremarkable. An ECG, complete blood count, and urinalysis are performed. The former two investigations show no abnormalities, while the latter is only positive for microscopic hematuria, with no pus cells, and negative nitrite and leukocyte esterase dipstick tests.
The ultrasound scan of the renal system appears normal.
There is a solitary, small, radio-opaque mass ~8 mm x 5 mm in size, and ~845 HU (Hounsfield Units) in density, in the proximal third of the right ureter. Both kidneys, the left ureter, and bladder appear normal.
Urine culture reports will be available in 24 to 48 hours.
You realize that intravenous urography is not the most preferable investigation here.