Inverted diverticulum

Fig. 13.3a,b. Inverted diverticulum pseudopolypoid shape on virtual endoscopic images. On 2D images, these lesions contain some air, residual stool, or fat attenuation because of a central umbilication in the inverted part of the diverticulum or due to an inclusion of perisigmoidal fat. (Used with permission of Lefere et al. 2003)... 

Fig. 5.13. Lead-point lesion in intussusception, a Adenomatous polyp, b Inflammatory polyp, c Inverted Meckel s diverticulum seen as cystic mass...

A diverticulum may occasionally invert into the colonic lumen and produce a pseudopolypoid lesion. 

Click SN (1991) Inverted colonic diverticulum air contrast harium enema findings in six cases. Am J Roentgenol 156561-964... 

Differential diagnostic problems can occur if a diverticula inverts into the colonic lumen or is impacted with stool. A diverticulum may occasionally invert into the colonic lumen and produce a pseudopolypoid lesion on 2D and 3D images. The corresponding VE image is nonspecific and shows a polypoid lesion (Fig. 13.3a,b). The 2D images are essential to arrive at the correct diagnosis inverted diverticula with pseudopolypoid shape sometimes... 

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