1. Department of Surgery, University Hospital ‘Tzaritza Joanna - ISUL', Medical University of Sofia, Sofia, Bulgaria
2. Department of Medical Imaging, University Hospital ‘Tzaritza Joanna - ISUL', Medical University of Sofia, Sofia, Bulgaria
3. Department of General and Clinical Pathology, University Hospital ‘Tzaritza Joanna - ISUL', Medical University of Sofia, Sofia, Bulgaria
4. Department of Surgery, MBAL ‘Higia', Pazardzhik, Bulgaria