الفهرس 
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Abstract
Improvements in cross-sectional imaging have led to a rise in the detection of renal masses in recent years. The use of US for the identification of renal masses and tumors continues to be the gold standard, with CT and MR employed for improved detection, characterisation, and staging.
Appropriate case treatment, aid in staging and prognosis, and the ability to distinguish surgical lesions from nonsurgical lesions all depend on an accurate characterisation of renal masses.
Diffusion-weighted imaging (DWI) is a functional imaging method that uses the differential movement of water molecules in tissues to create an image’s tonal contrast.
DW pictures are taken at three distinct b-values (250, 500, 1000) so that an ADC map can be calculated, allowing for more nuanced interpretation. Quantitative examination of diffusion in individual tissues may be performed by manually outlining areas of interest on an ADC map and then calculating the corresponding ADC values. Instead, qualitative analysis may be performed by only looking at the b-value pictures and the related ADC map to derive conclusions. Signal loss from water molecules is amplified in images captured at high b-values (i.e. 1000 s/mm2).
Therefore, regions of retained (bright) signal on high b-value pictures and regions of low signal intensity on the related ADC map with low ADC value indicate biological tissues such as tumors that demonstrate the highest degree of limited diffusion.
Patients at risk for nephrogenic systemic fibrosis or nephrotoxicity due to renal insufficiency may benefit greatly from DW MRI’s noninvasive approach to evaluating renal and upper urinary tract malignancy since it does not need intravenous contrast.
Our research was to determine whether diffusion weighted MR imaging may aid in the characterisation of renal malignancies, and we found that benign renal masses had a considerably higher ADC value than malignant renal masses.
Classification of lesions:
Histopathological findings were compared with imaging and/or MR follow-up outcomes for each patient.
Twenty lesions were verified by pathology. 12 patients received radical resection, 4 got partial resection, and 4 were verified by Tru-cut biopsy; in all, 16 patients underwent surgical resection.
The most common malignancy was renal cell carcinoma (14/28), followed by lymphoma (2), Angiomyolipoma (2), oncocytoma (1%), and Wilm’s tumor (1%).
Lesions’ signal strengths on T1, T2WI were documented.
T1 Weighted imaging revealed that 14 of the 18 lesions (70%) produced weak signal, 4 of the 18 lesions (20%) produced intermediate signal, and 2 of the 18 lesions (10%) produced isointense signal.
Nine lesions (45%) showed up as strong signal on T2 Weighted images, whereas eleven lesions (55%) showed up as low signal.
Image diffusion and the relative importance of ADC:
Normal renal parenchyma and renal lesions with b value 250, 500, and 1000 s/mm2 had their respective ADC values determined.
When comparing the ADC values of normal renal parenchyma, benign lesions, and malignant lesions at a b value of 250 s/mm2, the normal renal parenchyma ADC varied from 1.621 to 2.591 x 103 mm2/s (mean 2.016 0.15).
In the case of benign renal lesions, the ADC value was on average 1.99 0.88 x 10-3 mm2/s, with a range of 1.19 to 2.947 x 10-3 mm2/s. Malignant renal lesions had an ADC value that varied between 0.7543 and 1.579 x 10-3 mm2/s (mean 1.15 0.26 x 10-3 mm2/s).
Using a b value of 500 s/mm2, we compared the ADC values of normal renal parenchyma to those of benign and malignant tumors.
Typical renal parenchyma had an ADC of 2.016 0.15 x 103 mm2/s (range, 1.621–2.591).
Normal renal lesions had an ADC of 1.74 0.73 x 103 mm2/s (range, 1.031–2.954 x 10-3 mm2/s). Cancerous renal lesions had an ADC of 1. 0.22 x 10-3 mm2/s (range, 0.665–1.377 x 10-3 mm2/s).
Three-way comparison of ADC values at b = 1000 s/mm2 between normal renal parenchyma and benign and malignant lesions:
Typical renal parenchyma had an ADC of 2.016 0.15 x 103 mm2/s (range, 1.621–2.591).
To put it another way, benign renal lesions had an ADC value between 1.001 and 1.997 x 103 mm2/s (mean 1.49 0.49 x 10-3 mm2/s). Malignant renal lesions had an ADC of 0.546-1.167 x 103 mm2/s (mean 0.86 0.19 x 10-3 mm2/s).
As the ADC values of benign and malignant lesions vary widely and overlap, relying just on ADC value alone to evaluate renal lesions might be problematic. It is possible to improve diagnostic accuracy while evaluating renal lesions by combining traditional MRI with ADC value.
Since DWI with low and high b values (b 250, 500, and 1000) and quantitative ADC measurements is a relatively accurate method for renal lesion characterization and may be helpful in differentiating benign and malignant renal lesions, we propose incorporating it into a routine renal MR imaging protocol.