Prevalence of incidental Bochdalek's hernia in a large adult population

OBJECTIVE. The purpose of this study was to determine the prevalence and ch aracteristics of adult Bochdalek's hernia in a large patient population. MATERIALS AND METHODS. We retrospectively reviewed all abdominal CT scans o btained at our hospital in 1998, Patients in our study were identified thro ugh a keyword search of our database for "Bochdalek," "hernia," and "diaphr agm." The individual patient studies identified were reviewed in a soft-cop y format. We noted the location and side of the body on which the diaphragm atic hernia arose and the contents of the sac. We also performed a chart re view for each patient included in the study, noting the patient's sex, age, and symptoms. RESULTS. Incidental Bochdalek's hernia was diagnosed in 22 patients (17 wom en, five men), which represents an incidence of 0.17% based on 13,138 abdom inal CT reports we reviewed. The mean age of the patients was 66.6 years. N one of the patients were symptomatic. Sixty-eight percent of the hernias we re on the right side of the body, 18% were on the left side, and 14% were b ilateral. Seventy-three percent contained only fat or omentum, whereas 27% had solid or enteric organ involvement including the spleen, small intestin e, or large intestine. CONCLUSION, Bochdalek's hernia is not rare, and the incidence of Bochdalek' s hernias that contain enteric tract is higher than previously reported. Th is incidence likely represents a conservative estimate because some Bochdal ek's hernias may have been overlooked or unreported.