RESUMO
BACKGROUND: Colonic manometry is a widely used method to assess digestive tract function and is of crucial importanoe in evaluating colonic activity disorder.OBJECTIVE: To analyze the kinematic and kinetic eatures f intestinal tract pressure signal of healthy volunteers and patients with abnormal colonic pressure.DESIGN: Contrast observation experiment.SETTING: People's Hospital of Shanghai Pudong New Area.PARTICIPANTS: Two groups of participants were organized. The patient group consisted of six patients ith abnormal colonic function. They received treatment in the People's Hospital, Shanghai Pudong New Area etween January 2000 and August 2001. These patients were not allowed to take any medicine or foods that ould affect intestinal motility within two weeks prior to the study. The control group consisted of nother 2 healthy volunteers who received health examination homeochronously. Informed consents were btained from all the participants. Gastrointestinal tract functionamonitor manufactured by CTD2SYNETICS ompany (Sweden) was employed.METHODS: Participants were asked to lie down on their left sides for 30 inutes quietly before the manometer entered the ileum with the help of an enteroscope. A water bag was ttached to the end of manometer and was filled with water to increase the end weight. The enteroscope was sed to inhale the intra-intestinal gas while it was pulled out. Afterwards, the water bag was emptied. Easurement began after the participant was asked to lie down for another 30 minutes to deplete the bnormal contraction of intestinal tract caused by enteroscope. Every inspection took about 20 minutes. Ubsequently, the water bag was filled with 50 mL water and the gas bag with 50 mL air to simulate the timulation of faeces. The simulation inspection also lasted about 20 minutes. During the measurement rocess, the precise position was determined by a B-type ultrasonic inspection system. The manometer was hen pulled out 20 cm and the same inspection process was repeated. Fractal dimension of intestinal tract ressure was calculated with the method from Higuchi to distinguish normal and abnormal colonic pressure ignal.MAIN OUTCOME MEASURES: Fractal dimension analysis of intestinal tract pressure signals.RESULTS: xtensive analysis was conducted for pressure signals of two healthy volunteers and six patients. The racta dimensions of intestinal tract pressure data from normal subjects basically kept around a certain alue, while those from patients varied greatly. There was something wrong with colonic contractions of ntestinal tract of the patients, as the associated fractal dimensions, were around "1".CONCLUSION: ractal imension of intestinal tract pressure signals is calculated, and the resultant fractal dimension can be sed as an index to distinguish normal and abnormal colonic pressure signals.