Is lymphatic status related to regression of inflammation in Crohn's disease?

Figure 1 Healthy small bowel. A: the Patent Blue injected into the subserosal layer outlines a lymphatic vessel which rectilinearly goes into the mesenterium towards the lymph-node (arrow). Lymphatic vessels longitudinally directed are not observed; B: Small bowel affected by Crohn’s disease: the Patent Blue injected at the level of a skip lesion outlines a lymphatic vessel longitudinally directed in the small bowel wall and only from this site can it spread into the mesenterium.

Figure 2 Small bowel affected by Crohn’s disease. The Patent Blue injected into the subserosal layer soon leads to a high pressure spillage from the site of injection which highlights the absence of lymphatic drainage pathways (arrow).

Figure 3 Intestinal tracts previously treated by Heineke-Mikulicz strictureplasty, that do not appear macroscopically affected by recurrence of Crohn’s disease. The injection of Patent Blue soon highlights a lymphatic vessel which rectilinearly goes into the mesenterium towards the lymph node (arrows).

Figure 4 Previously performed side-to-side isoperistaltic strictureplasty. A: The lymph vessels appear straight and thin and easily reach the mesentery and the lymphnodes (arrows); B: Once the side-to-side isoperistaltic strictureplasty was resected, Crohn’s disease remission was visible at the internal site of dye injection, by the normal aspect of the mucosa.

Figure 5 Intestinal tract previously treated by Heineke-Mikulicz strictureplasty, that appears macroscopically affected by recurrence of stenosis in Crohn’s disease. A: the injection of Patent Blue quickly highlights a lymphatic vessel which rectilinearly goes towards the mesenterium; B: However, the vessel is cut off before entering into the mesenterium; in the meantime a lymphatic vessel that runs tangential to the wall of the ileum is drawn (arrow).