The lateral view in the radiology of the rectum and rectosigmoid

Width of the presacral space in Nigerian adults

The width of the presacral space and the thickness of the rectal valve were measured on lateral radiographs obtained during barium enema examinations performed on 182 Nigerian adult patients over a 5-year period (1980-1984). The mean width of the presacral space was 0.78 cm, the value in men being significantly higher than in women (p less than 0.01). Although these values are similar to those reported among Caucasians, a wider range of normal values was obtained in this study. There is also no significant difference between the mean value of the rectal valve thickness of 4.3 mm obtained in this study and that obtained from previous studies.

The retrorectal space

Ninety-nine adults with an enlarged retrorectal space on barium enema examination have been evaluated. Measurements were based on previously described methods using the lateral view of the barium filled rectum. In 38.4% of the cases there was no lesion (normal variations). The rest were classified as inflammatory conditions, tumours, and miscellaneous lesions. It is concluded that an increased width of the presacral space per se does not necessarily connote a lesion. Pathological widening of the space is usually associated with changes of the contour of the rectum, abnormalities of the sacrum, or other alterations of the presacral soft tissues.