'Gold standard' in diagnosis of GERD is

24-hour pH recording is the 'gold standard' for diagnosis of GORDNormally endoscopy with biopsy is done. If the typical appearance of reflux oesophagitis, peptic stricture or Barrett's oesophagus is seen, the diagnosis is clinched,In patients with atypical or persistent symptoms despite therapy, oesophageal manometry and 24-hour oesophageal pH recording (ideally with impedance measurement) is done.Manometry and pH recording are essential in patients being considered for antireflux surgery.A CT scan gives the best appreciation of gastro-oesophageal anatomy. This may be impoant in the context of surgery for rolling or mixed hiatus hernias,Ref: Bailey and Love 27e pg: 1078