Three-Dimensional Imaging Of The Lower Esophageal Sphincter In Gastroesophageal Reflux Disease,Healthy Subjects And Achalasia

Objective: It is reported that the inner semicircular clasp fibers and the slinglike obliqe gastric fibers at the gastroesophageal junction may plays an important role in the formation of the high pressure zone(HPZ) of the lower esophageal sphincter(LES). The human LES is not a muscular ring. The resistance provided by the manometric HPZ at the gastroesophageal junction, is the major barrier against gastroesophageal reflux in man. Traditional manometric evaluation of the HPZ at the gastroesophageal junction usually is performed by measuring its resting pressure or the length of the HPZ, this method has been shown to be inadequate to identify individual patients with mechanically defective sphincters because of the large overlap with normal subjects. There remained a large number of patients with adequate sphincter pressure who had increased esophageal acid exposure on 24-hour esophageal pH monitoring. The new techinique (three dimensional(3D) imaging of the LES) allowed intergration of the sphincter length and pressure into one parameter, termed the sphincter pressure vector volume(SPW). We compared 3D imagingof the LES with traditional manometry in some patients with gastroesophageal reflux disease (GERD). Based on this, we can select the techinique that provided the best discrimination of the patients with GERD. The effect of Nissen fundoplication and Heller myotomy on the 3D sphincter pressure profile also was evaluated.Materials and Methods: fourty healthy volunteers, fifteen patients with GERD, eight patients with achalasia, were selected in this study. Medications known to interfere with gastro-intestinal secretory or motor function were discontinues at least 48 hours before the test, and food or water were prohibited at least 6 hours before the test. The manometric catheter assembly was passed through an anesthetired nostril into the stomach, and the gastric pressure pattern was confirmed. The catheters were perfused with distilled water at a constant rate of 0.6ml/min using an Arndorfer pneumohydraulic low-compliance perfusion pump. We pulled the catheter untill it passed the position of LES. The recorder transported the data into computer, which can analysis the data and show the 3D imaging. This study concluded four ports: 1. In 20 healthy volunteers, the normal range of the SPVV were evaluated. 2. 15 patients with GERD and 20 normal volunteers were used to calculate the sensitivity of the SPVV and the resting pressure, then we compared the two methods. 3. Using the new method, the same 15 patients with GERD had follow-up studies 2 weekesafter Nissen fundoplication. We compared the postoperative SPVV with preoperative SPVV. 4. 8 patients with achalasia were used to obtain the preoperative SPVV and the postoperative SPW, then we compared the two groups.Results: 1. The 3D imaging showed that there is a high pressure zone at the gastroesophageal junction and it is the position of the LES. Manometric 3D images of the LES showed a marked radial and longitudinal asymmetry. Radial pressure were highest toward the left posterior direction. 2. The normal range of human LES pressure vector volume is 4526-7409 mmHg2cm. 3. SPVV of normal volunteer were higher than SPVV of the patients wish GERD (p<0.05). postoperative SPVV were higher than preoperative SPVV (p<0.05). Postoperative SPVV had no difference with normal volunteers (p>0.05). 4. The SPVV of patients with achalasia were higher than normal volunteer' s (p<0.05). Postoperative SPVV were lower than preoperative SPVV (p<0.05). Postoperative SPVV were higher than normal volunteer' s (p>0.05). 5. The sensitivity of the resting pressure was 73.3%. The sensitivity of the SPVV was 93.3%. There is a difference between two methods (p<0.05). The latter is more sensitive.Conclusions: 1. Three dimensional imaging of the lower esoohageal high pressure zone showed a marked radial and longitudinal asymmetry. 2. 3D imaging of the LES with calculating its SPW is superior to the traditional manometry with measuring its resting pressure, it should become...