Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Role of diffusion-weighted MRI in acute pyelonephritis: a prospective study. Acta Radiol 2015 Feb;56(2):244-9 PMID: 24443116


BACKGROUND: Imaging is vital in diagnosis of complicated pyelonephritis and has been traditionally performed by computed tomography (CT). However, CT with contrast agents cannot be performed in patients with renal failure. Diffusion-weighted (DW) magnetic resonance imaging (MRI) has the potential to overcome this disadvantage.

PURPOSE: To prospectively evaluate the accuracy of quantitative apparent diffusion coefficient (ADC) values to differentiate nephritis from renal abscesses in patients with pyelonephritis.

MATERIAL AND METHODS: Forty-two patients with clinical and laboratory diagnosis of pyelonephritis underwent CT and DW MRI examinations. Diffusion images were obtained by using a non-breath-hold, single-shot echo-planar sequence with b values of 0, 600, and 1000 s/mm(2). Circular regions of interest were places on areas of nephritis, normal renal parenchyma, and renal abscesses as localized by CT and DW MRI images to obtain the ADC values of each of these regions. The ADC values of these three different tissue types were statistically compared using the one-way analysis of variance test for statistical significance. A P value <0.05 was considered to be statistically significant.

RESULTS: For the diagnosis of pyelonephritis, DW MRI had a higher sensitivity of 95.3% as compared to that of non-contrast CT (66.7%) and contrast-enhanced CT (88.1%). Areas of nephritis had significantly lower ADC values (P < 0.001) than the normal renal cortical parenchyma. Also, renal abscesses had significantly lower ADC values (P < 0.001) than areas of nephritis. However, CT is more useful for the diagnosis of renal calculi and emphysematous pyelonephritis.

CONCLUSION: ADC values derived from the diffusion sequence have significantly lower values in renal abscesses than in areas of nephritis.

Author List

Rathod SB, Kumbhar SS, Nanivadekar A, Aman K


Sachin Kumbhar MD Assistant Professor in the Radiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged, 80 and over
Diagnosis, Differential
Diffusion Magnetic Resonance Imaging
Image Enhancement
Image Interpretation, Computer-Assisted
Middle Aged
Reproducibility of Results
Sensitivity and Specificity
Tomography, X-Ray Computed

View this publication's entry at the Pubmed website PMID: 24443116
jenkins-FCD Prod-164 dfc08cb8c9ba6489ef52627ede450784778aa7cb