Abstract:

Purpose. Was to investigate the role of diffusion weighted imaging (DWI) in focal hepatic lesions diagnostic.

Material and methods. Data of 70 patients (20 men) aged 28-78 years with focal hepatic lesions were analyzed. All of them underwent 1,5 T MRI; DWI obtained at b values of 50 s/mm2, 400 s/mm2, and 800 s/mm2. The results of MSCT data, intra-operative visual and ultrasound examination, histology of operation probes, and follow-up data were confermed.

Results. In 70 patients 203 focal lesions sized 3-168 mm: cysts (55), angiomas(36), metastases (89), nodal hyperplasia(5), primary tumors (5), abscesses (5), focal necroses (2) were revealed. DWI is capable of making differential diagnosis of focal hepatic lesions: cysts were not visualized at b = 800 s/mm2, and their ADC was (2,5 ± 0,2) × 10~3 s/mm2. Metastases were visible in all b-values, and had ADC lower than that for cysts (1,2 ± 0,5) × 10~3 s/mm2). Angiomas also were good visualized in all b-values, but ADC of angiomas was higher and varied from 1,5x 10~3 to 2,6 x 10~3 s/mm2. DWI is advantageous in detecting of small (less than 1 cm) foci: even if this kind of lesions was indistinct atT1 and T2 weighed images, DWI showed high intensity and well-defined edges.

Conclusions. Diffusion weighed MRI appeared to play additional role in differential diagnosis of focal hepatic lesions, enhancing detectabi-lity of the small (less than 1 cm) foci. The technique is simple, cost-effective and not time-consuming. 

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