- BACKGROUND: Conventional 3-dimensional endoluminal US was modified to evaluate peristaltic contractions in the esophagus. METHODS: Two-dimensional US images and simultaneous intraluminal pressures were acquired during peristaltic contractions by locating the transducer at fixed positions in the esophagus in 6 normal volunteers during swallowing. Three-dimensional images were reconstructed by using a computer-based 3-dimensional algorithm with time as the x axis. RESULTS: The peristaltic contraction sequence was viewed as a 3-dimensional US image. The geometric configuration of the esophagus, the muscle thickness, and corresponding pressures were evaluated. The 3-dimensional images demonstrate 4 phases of the peristaltic contraction sequence. CONCLUSIONS: Three-dimensional time-resolved reconstruction of endoluminal US images of the esophagus and simultaneous recording of manometric data allow visualization of geometric changes and correlation with pressure changes during peristaltic contraction. Four phases of the peristaltic contraction sequence are demonstrated clearly on the 3-dimensional space-time images.