Michael Petri

Stereomicroscopic examination of stained rectal biopsies.

The normal mucosal surface morphology in the rectum has been described by investigation of 15 rectal biopsies using a semimacroscopic technique. The structures of the mucosal surface were rendered visible by staining the biopsies as whole mounts with Alcian Green. A regular pattern of the crypt openings was found, and the goblet cells were observed in and just around the crypt openings. The density of crypt openings was calculated as the number of crypt openings per square millimetre (104 +/- 23 openings per mm2, mean and S.D.). Histologic examinations of the same biopsies were performed, and the density of crypt tubules was calculated from serial, horizontal sections (130 +/- 34 tubules per mm2, mean and S.D.). The ratio of crypt openings/crypt tubules was 1:1.25, indicating some branching of the mucosal glands in the rectum.

Stereomicroscopic Examination of Stained Rectal Biopsies in Ulcerative Colitis and Crohn's Disease

Rectal biopsy samples from 22 healthy control subjects, 54 patients with ulcerative colitis, and 34 with Crohns disease with involvement of the colon or rectum were investigated in a stereomicroscopic study. Samples were stained as whole mounts with Alcian Green before the stereomicroscopic examination. In ulcerative colitis, biopsies almost constantly showed changes in the mucosal surface pattern, including irregular, enlarged crypt openings filled with exudate, granulated and bulging surface, and patchy localization of the goblet cells. There was a close correlation between the stereomicroscopic findings and the clinical disease activity, the sigmoidoscopic findings, and the histologic activity. Apart from the stereomicroscopic observation of small superficial erosions in one fourth of the biopsies, no changes of diagnostic value were observed in Crohns disease.