**Author details**

Tsvetelina Teneva1 \*, Aleksandar Zlatarov2 and Rozen Grigorov3

1 Department of Imaging Diagnostics, Medical University Prof. Dr P. Stoyanov, Varna, Bulgaria

2 Department of General and Operative Surgery, Medical University Prof. Dr P. Stoyanov, Varna, Bulgaria

3 Medical University Prof. Dr P. Stoyanov, Varna, Bulgaria

\*Address all correspondence to: tenevaz@gmail.com

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