Role of Crural Diaphragm after Esophagogastrectomy

Cho, Sung Rae; Ha, Hyun Cheol; Lee, Bong Keun; Cho, Bong Gyun

Abstract

BACKGROUND: The high pressure zone(HPZ) at the gastroesophageal junction is an important barrier for prevention of gastroesophageal reflux. Smooth muscle layers in the lower esophageal sphincter mainly contributes to HPZ at the throacoabdominal junction. The purpose of this study was to investigate the manometric characteristics of the thoracoabdominal junction in patients after surgical removal of the lower esophageal sphincter. MATERIAL AND METHOD: Twenty two patients with prior esophagogastrectomy(10 Ivor-Lewis method and 12 left thoracotomy) and 30 normal adults(control group) were studied manometrically. RESULT: Esophageal manometry showed a HPZ and pressure inversion point distal to the anastomosis in 12 of 22 patients(2 of 10 patients with Ivor-Lewis method and 10 of 12 patients with left thoracotomy) and a HPZ in 30 of 30 normal adults. The location of HPZ from nostril was not significant different between the two groups(42.5+/-0.9cm in patients and 43.9+/-2.1cm in the control), while the length of HPZ was shorter in patients than in the control(2.13+/-0.6cm vs 2.83+/-0.59cm). By SPT and RPT, pressures of HPZ at rest were lower in patients(13.78+/-1.63mmHg, 28.58+/-6.06mmHg) than in control(20.3+/-4.95mmHg, 42.80+/-15.91mmHg). The HPZ relaxed partially in response to deglutition(84.4% in patient, 90.5% in control group) and contracted in response to increased intra- abdominal pressure induced by leg lifts(HPZ/ Intra-abdominal pressure= 1.81+/-0.23 in patient, 2.13+/-0.58 in control group).
CONCLUSION
This study shows an HPZ at thoracoabdominal junction after surgical removal of the lower esophageal sphincter. It may be important to perform a crural myoplasty during esophageal reconstruction after esophagogastrectomy because crural diaphragm acts as sphincter like HPZ at the thoracoabdominal junction.