Diffusion-weighted magnetic resonance imaging findings of kidneys with obstructive uropathy: differentiation between benign and malignant etiology.

Tugce Ozlem Kalayci,Melda Apaydin,Fitnet Sönmezgöz,Melike Bedel Koruyucu,Sinan Çalık

doi:10.1155/2014/980280

Tugce Ozlem Kalayci, Melda Apaydin + Show 3 more

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https://doi.org/10.1155/2014/980280

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Journal: TheScientificWorldJournal	Publication Date: Jan 1, 2014
Citations: 4	License type: CC BY 3.0

Affiliation: Fırat University

Abstract

Purpose. In this study, we aimed to evaluate the capability of diffusion-weighted magnetic resonance imaging (DWI) in differentiation between benign and malignant etiology of obstructive uropathy. Materials and Methods. DWI was performed in 41 patients with hydronephrotic kidneys and 26 healthy volunteers. MR imaging was performed using a 1.5 T whole-body superconducting MR scanner. The signal intensities of the renal parenchyma on DWI and apparent diffusion coefficient (ADC) maps were noted. DWI was performed with the following diffusion gradient b values: 100, 600, and 1000 s/mm2. A large circular region of interest was placed in the corticomedullary junction of the kidneys. For statistical analysis, the independent-samples t test was used. Results. The mean renal ADC values for b100, b600, and b1000 in hydronephrosis patients with benign and malignant etiology and the healthy volunteers of the control group were analysed. ADC measurements of renal parenchyma in all hydronephrotic kidneys with benign and malignant etiology were found to be statistically low compared to those of normal kidneys (P < 0.05). Conclusions. There were significant differences in the ADC values of obstructed kidneys compared to those of normal kidneys. Obstructed kidneys with malignant etiology had lower ADC values for b1000 compared to obstructed kidneys with benign etiology, but these alterations were statistically insignificant.

Highlights

Diffusion-weighted magnetic resonance imaging (DWI) is used to show the Brownian motion of the spins in biologic tissues and can be used to differentiate between normal and abnormal tissue structures
No papers have been published on DWI in obstructive uropathy patients for discrimination between benign and malignant etiology
The colour change was observed on the apparent diffusion coefficient (ADC) maps that were created from DW echoplanar images, depending on increasing b value and decreasing ADC coefficients; the colour shift from red to yellow/green was observed much more in hydronephrotic kidneys than in normal kidneys to be compatible with lower ADC values (Figure 2)

Summary

Introduction

Diffusion-weighted magnetic resonance imaging (DWI) is used to show the Brownian motion of the spins in biologic tissues and can be used to differentiate between normal and abnormal tissue structures. The apparent diffusion coefficient (ADC), as the main quantitative parameter used to interpret DWI, combines the effects of capillary perfusion and water diffusion in the extracellular extravascular space [1]. With the advent of echoplanar imaging (EPI) in conjunction with breath-holding, DWI of the abdomen has become possible with fast imaging times, minimizing the effect of gross physiologic motion from respiration and cardiac movement. With its complex anatomic structure and physiology, the kidney is extremely challenging for DWI [3, 4]. Obstructive uropathy can occur due to some benign and malignant conditions. No papers have been published on DWI in obstructive uropathy patients for discrimination between benign and malignant etiology

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