<prompt> In extended supraomohyoid neck dissection, lymph Node dissection is done up to:IIIIIIVV  <response>: Selective Neck Dissection - Supraomohyoid neck dissection: Removal of level I-III LNs - Extended supraomohyoid neck dissection: Removal of level I-IV LNs - Posterolateral Neck Dissection: Removal of level II-V LNs suboccipital LNs retro auricular LNs - Lateral neck dissection: removal of level II-V LNs Internal jugular vein - Central compament neck dissection: Removal of level VI LNs 