1. THE ROLE OF MRI AND DWI IN THE DIFFERENTIAL DIAGNOSTIC DILEMMA - METASTATIC MALIGNANT MELANOMA OR HAEMANGIOMA?
Bilal Imsirović, Emir Gušo, Zulejha Merhemić,
Anesa Čengić, Zlatko Handžić, Tamara Jovović Sadiković, Mirza Palo

2. Introduction
In everyday radiological practice, different focal changes in the liver often represent a differential diagnostic problem. The correct diagnosis, especially for cancer patients, is crucial for the proper therapeutic effect. Often there are situations when certain focal lesions, with their radiological characteristics, "imitate" some other, and in the diagnostic sense are misleading. Ultrasound and computed tomography in spite of their advantages (availability, simplicity, cost), are often limited by to certain aggravating factors (pain, obesity, gas in intestines, ionizing radiation) and on the other side Magnetic resonance imaging, wherever possible, is imposed as superior method of examination.

3. Case informations
In this case report we present case of 33 years old female patient with diagnosed Malignant Melanoma on right arm, operationally and histologically confirmed metastases in regional lymph nodes, and the ultrasonic diagnosis (PHILIPS EnVisor M2540A ultrasound system) of metastatic lesions in the liver. After an MRI processing (SIEMENS Magnetom Avanto, 1.5 T, Erlangen, Germany), in the liver parenchyma were verified multiple focal changes of which several of them were, by their MRI characteristics, indisputably suit as haemangioma, while some them with peripheral nodular dyeing, which is characteristically for haemangioma, but the restriction of diffusion of free water, visible on diffusion sequences (ADC and DWI), was pointing to their metastatic origin.

4. Restriction of difussion-patognomonic for metastasis
Focal lesion (metastasis of Malignant Melanoma) in liver parenchyma, located near IVC
T1W-hypointense
T2W-hyperintense
T1W arterial phase
discrete marginal dyeing
T1W extended phase
discrete marginal noduar dyeing
DWI-hyperintense
ADC-hypointense
Restriction of difussion-patognomonic for metastasis

5. No restriction of difussion
Focal lesion (haemangioma) in liver parenchyma, located in right lobe (segment IV and VII)
T1W-hypointense
T2W-hyperintense
T1W arterial phase
discrete marginal dyeing
T1W extended phase
discrete marginal noduar dyeing
DWI-hyperintense
ADC-hyperintense
No restriction of difussion

6. Conclusion
The versatility of MR recording and the amount of diagnostic informations obtained from MRI examination is huge. Comparison of MRI sequences obtained, facilitate interpretation of these findings. Obtained MRI information and available literature, correlating with other diagnostic modalities (ultrasound and CT) facilitate understanding of the specific pathology.