摘要 |
Disclosed is an esophageal catheter that is capable of simultaneously measuring impedance, hydrostatic pressure and contact pressure in an esophagus from peristaltic waves, esophageal fluid and the transit bolus in a single test episode. Circumferential impedance sensors include sensing electrodes that are oppositely disposed on the circumferential impedance sensor, and reference electrodes that are also oppositely disposed on the circumferential impedance sensor and interspersed between the sensing electrodes. Accurate impedance measurements can be made in this fashion in a transverse direction in the esophagus. A hydrostatic pressure sensor is disposed at the distal tip of the esophageal probe that has a rigid cover to protect the hydrostatic pressure sensor from contact pressures of the esophagus. In this manner, the hydrostatic pressure sensor can provide purely hydrostatic pressure data from the fluids in the esophagus. Disposed above the hydrostatic pressure sensor, at the distal end of the probe, is an optical contraction sensor that detects both hydrostatic and contact pressure, by detecting the occlusion created by a flexible membrane disposed between an optical source and an optical detector mounted longitudinally in the probe, in response to contractions at the esophagus. The output of the hydrostatic pressure sensor and the optical contraction sensor permits estimations to be made of the contact pressures created by the esophagus.
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