REGIONAL DIFFERENCES IN PASSIVE ELASTIC WALL PROPERTIES OF THE ESOPHAGUS - AN IMPEDANCE PLANIMETRIC STUDY IN PIGS

Regional differences in biomechanical properties of the oesophagus wer e studied in seven healthy Goettingen minipigs by means of impedance p lanimetry. The investigation was done during anaesthesia by stepwise p ressure-induced balloon distensions with concomitant measurement of pr essure and luminal cross-sectional area (CSA) in the oesophagus 5, 10 and 15 cm above the gastro-oesophageal junction (GEJ). The compliance and wall tension were computed from measurements of the pressure and s teady-state CSA. Probably due to the anaesthesia, only scant peristals is was recorded and the CSA always reached steady state during balloon distension. The CSAs were highest in the distal oesophagus (P < 0.01) . At the highest induced pressure, the figures were 665 +/- 57, 529 +/ - 50 and 452 +/- 47 mm2 for the locations 5, 10 and 15 cm from the GEJ , respectively. Hysteresis did not differ between the measuring points . The oesophagus was significantly more compliant at low pressures (1- 3 kPa) 5 cm above the GEJ compared to the more proximally located meas uring points (P < 0.05). In conclusion, regional variations occurred i n passive biomechanical properties of the oesophagus with the highest distensibility occurring 5 cm above the GEJ.