In instances of severe reflux, surgical treatment can include the “Nissen Fundoplication''. In this procedure, the fundus of the stomach is wrapped around the lower oesophagus and fixed with sutures to prevent sliding, while the right crus of the diaphragm is also tightened with sutures to reinforce the lower oesophageal sphincter. Based on the description of the Nissen Fundoplication, which structures may be at risk in this operation, particularly as the oesophagus passes through its hiatus in the diaphragm?