The value of T1 mapping magnetic resonance imaging in detecting renal parenchymal edema, inflammation, and fibrosis associated with urinary tract stone disease

Urinary stone disease can cause kidney damage via renal parenchymal edema, inflammation and fibrosis, especially when it causes obstruction. T1 mapping magnetic resonance imaging (MRI) may contribute to the diagnosis of such damage. The purpose of our study was to evaluate the stone-related parenchymal edema-inflammation-fibrosis in patients with unilateral renal pelvis - ureter stones, by measuring the T1 relaxation time of the parenchyma of kidney with stone [stone (+)] and the kidney on the other side [(stone (-)]. Thirty-five patients with unilateral urinary stone were prospectively analyzed by T1 mapping MRI. In the stone (+) and stone (-) system, T1 signal values of the renal cortices were measured on the transverse and coronal planes. The consistency of the measurements obtained by two different radiologists and also the correlation of the measurements with the parameters such as age, gender, stone area, stone size, hydronephrosis degree were statistically evaluated. The mean age of the patients (12 male, 23 female) were 41.11 ± 16.37 years. T1 values measured by two radiologists were found to be highly concordant (p<0.05). T1 values measured on transverse and coronal images were found to be significantly higher in the stone (+) system than in the stone (-) system (p<0.05). There was a significant difference between the genders in terms of T1 values (p<0.05). The degree of hydronephrosis was affecting the T1 value while parameters such as stone size, stone region, patient age was not affecting. It was determined that as the T1 value increased in the stone (+) system, there was an increase in the stone (-) system as well. In conclusion, it is thought that T1 mapping MRI can contribute as an auxiliary method in showing changes such as edema, inflammation and fibrosis in the renal parenchyma due to urinary tract stones.