Comparative Sutdy of MR Urography and Retrograde Pyelography in the Diagnosis of Patients with Urinary Tract Obstructiive Diseases

Objective:To compare the diagnostic value of magnetic resonance urography (MRU) and retrograde pyelography (RP) in patients with obstructive urinary tract diseases.Methods:15 patients with obstructive urinary tract lesions were examined with both MRU and RP at the same period and the diagnostic results with these two examination modalities were individually and correlatively compared with those of the pathological findings.Results:There were 2 cases of ureter tumors,6 cases of congenital ureter stricture,4 cases of ureter calculi and 3 cases of inflammatory fibrous stricture in our collection of 15 cases.Both MRU and RP were able to show the obstructive sites at the ureter clearly,and the lesion localization accuracy rates of the two modalities were identical,however,MRU was higher than RP in specificity (pathological nature) diagnosis accuracy.Conclusion:Higher accuracy rates of lesion localization and nature specificity were acquired with non-invasive MRU than with RP in the examination of patients with obstructive ureter diseases.MRU was believed capable of replacing RP as a role of imaging examination and the first choice of imaging modality in patients with obstructive ureter diseases,especially in those who were contraindicated to and intolerant of RP.