OBJECTIVE Endoscopic sphincter of Oddi manometry (ESOM) allows direct assessment of motor function in the sphincter of Oddi. However, variations in examination conditions and duodenal motility may have a critical effect on the results of ESOM. The aim of the present study was to develop a new method sphincter of Oddi video manometry-based on simultaneous ESOM and real-time endoscopic image analysis, and to investigate the usefulness of video manometry for detecting manometric artefacts during ESOM. METHODS Seven consecutive patients who had undergone cholecystectomy and were referred with a suspicion of sphincter of Oddi dysfunction were investigated. Sphincter of Oddi pressure and endoscopic images (20 frames/s) were recorded simultaneously on a Synectics PC Polygraf computer system with a time-correlated basis, and then compared. RESULTS On ESOM, 69 sphincter of Oddi phasic contractions were identified, with an average amplitude of 153.9+/-85.0 mm Hg and a duration of 7.9+/-1.2 seconds. Visual analysis of the real-time endoscopic images, replayed in cine loop by the computer, revealed 236 separate duodenal contractions, with an average frequency of 3.5+/-2.4/min (range: 1-12/min). On the ESOM tracing, 78% of the duodenal contractions had a corresponding pressure wave with an average duration of 2.8+/-0.4 seconds and an amplitude of 71.9+/-16.7 mm Hg. Other artefacts on the ESOM tracings, such as catheter movements, pseudocontractions, hyperventilation, or retching, were also easily recognized using simultaneous ESOM and real-time endoscopic image analysis. CONCLUSIONS Video manometry of the sphincter of Oddi is a promising new method for improving the analysis and documentation of ESOM tracings. It has several advantages over the conventional technique, allowing visual detection of duodenal activity and enabling enhanced recognition of other manometric artefacts.