sliding hiatal hernia

"axial hernia," "concentric hernia"

99% of hiatal hernias
portion of peritoneal sac forms part of wall of hernia
etiology: rupture of phrenicoesophageal membrane due to repetitive stretching with swallowing
incidence: increases with age

Findings:

UGI
- epiphrenic bulge
- distance between B ring and hiatal margin > 2cm
- tortuous esophagus
- gastroesophageal reflux
- > 6 thick gastric folds within suprahiatal pouch
CT
- dehiscence of diaphragmtic crura > 15 mm
- pseudomass within/above distal esophagus
- fat (omemtum) surrounding distal esophagus