الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 168 |  |  |
| | | from | 168 | | |
Abstract
H
ypervascular hepatic focal lesions may be benign or malignant. Therapy requires an accurate diagnosis, which in turn relies primarily on appropriate imaging and image-guided biopsy.
MRI having many sequences, markedly helps in the detection of small lesions and in reaching the diagnosis easily even without contrast injection or the need for biopsy as in hemangiomas.
For hepatic focal lesions detection and characterization, conventional MRI relies on T1-weighted, T2-weighted, and dynamic gadolinium-enhanced T1-weighted imaging.
DW MRI in the liver is a relative new and increasingly used imaging technique. It has the advantage that it can be obtained during a single breath-hold, there is no need to use contrast media and it provides unique information that reflects tissue cellularity and organization. The ADC maps can also provide quantitative measurements of tissue water diffusivity, which can be used not only for disease assessment, but also for the evaluation of disease response to treatment and/or detection of residual or early recurrent lesions.
In our study we concluded that diffusion-weighted MRI sequence with quantitative ADC measurements can be useful in the differentiation of benign and malignant hypervascular hepatic focal lesions.
Both qualitative evaluation of high b-value DW-MR images and quantitative evaluation of ADC maps are employed for lesion characterization. The ADC values of benign lesions are significantly higher than those of malignant lesions, with variable degrees of overlap between the pathological entities.
DWI proved to have value in the assessment of hypervascular hepatic focal liver lesions especially in detection of small lesions that are not clearly depicted by conventional sequences, but should always be used in conjunction with traditional MRI since there is great overlap between ADC values of benign and malignant lesions. It seems reasonable to use DWI in conjunction to conventional imaging for proper radiological characterization of the hypervascular hepatic focal lesions.