[Ambulatory esophageal pH monitoring: critical review of methodology: (equipment, reproducibility, standards), clinical importance and personal experience].

The authors review the recent literature about the methodology of oesophageal pH monitoring, which has a high sensitivity and a high specificity for assessing gastro-oesophageal reflux. Combined electrodes offer most advantages. Ambulatory recording should be done in hospital under standard conditions (meals), particularly for clinical studies. The best clinical indication is to detect pathological reflux in case of atypical symptoms with negative oesophagoscopy. The authors give their normal values in a series of measurements with two systems as well as their results in a series of cases of oesophagitis of various grades.