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Intrarenal Injection of Escherichia coli in a Rat Model of Pyelonephritis
Published on: July 18, 2017
Diffusion-weighted imaging and apparent diffusion coefficient values versus contrast-enhanced MR imaging in the
Riccardo Faletti1, Maria Carla Cassinis, Paolo Fonio
1Radiology Institute, Department of Surgical Sciences, University of Torino, Via Genova 3, 10126, Torino, Italy, riccardo_faletti@yahoo.it.
Objective:
To compare contrast-enhanced (CEMR) and diffusion-weighted (DWI) magnetic resonance imaging in diagnosing acute pyelonephritis (APN) and to assess ADC measurement reliability in differentiating among normal renal parenchyma, APN and abscesses.
Methods:
Eighty-eight patients (80 women, mean age 36.5 years) with clinical suspicion of APN were retrospectively reviewed. An experienced observer quantified lesions with a score ranging from 0 to 3. DWI and CEMR were compared on the basis of the assigned score, total examination number (88) and on presence (36)/absence (52) of abscesses. ADC values, calculated at the healthy parenchyma, APN and abscessed were compared to each other.
Results:
Agreement between CEMR and DWI was 94.3 % (83/88 patients; P < 0.05). In the APN group, DWI was awarded the highest visibility score compared to CEMR (P = 0.05), while in the abscess group CEMR had the highest score (P = 0.04). The difference between ADC values of the APN-healthy parenchyma and abscess-APN groups was significant (P < 0.05). The area under the ROC curve of ADC values of the APN-healthy and abscess-APN groups were found to be 0.94 (95 % CI; cutoff value = 2) and 0.78 (95 % CI; cutoff value = 1.2) respectively.
Conclusions:
Diffusion-weighted imaging appears reliable in the diagnosis and follow-up of acute pyelonephritis and could provide a reasonable alternative to contrast-enhanced magnetic resonance imaging.
Insights
Diffusion-weighted imaging (DWI) shows high reliability for diagnosing acute pyelonephritis (APN), offering a viable alternative to contrast-enhanced MRI. ADC values effectively differentiate between healthy tissue, APN, and abscesses.
Area of Science:
- Radiology
- Medical Imaging
- Nephrology
Background:
- Acute pyelonephritis (APN) is a common kidney infection.
- Accurate diagnosis is crucial for effective treatment and preventing complications.
- Contrast-enhanced magnetic resonance imaging (CEMR) is a standard diagnostic tool.
Purpose of the Study:
- To compare the diagnostic performance of diffusion-weighted imaging (DWI) and CEMR for APN.
- To evaluate the reliability of apparent diffusion coefficient (ADC) measurements in distinguishing normal renal parenchyma, APN, and renal abscesses.
Main Methods:
- Retrospective review of 88 patients with suspected APN.
- Comparison of lesion scoring between DWI and CEMR by an experienced observer.
- Analysis of ADC values in healthy parenchyma, APN, and abscesses.
Main Results:
- High agreement (94.3%) between DWI and CEMR.
- DWI showed higher visibility scores in APN, while CEMR was superior for abscesses.
- Significant differences in ADC values were found between healthy parenchyma, APN, and abscesses, with high diagnostic accuracy (AUC 0.94 and 0.78).
Conclusions:
- DWI is a reliable imaging technique for diagnosing and monitoring APN.
- DWI presents a potentially effective alternative to CEMR for APN diagnosis.
- ADC measurements are valuable for differentiating renal conditions.
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