There is a new technique for differentiating normal bowel from that involved with regional enteritis. At the time of operation, direct sky blue dye was injected beneath the serosa of the bowel. The distribution of the dye within the subserosa and mesenteric lymphatics was used to determine the site of bowel transection. Gross and microscopic findings were correlated with the test results. Six patients have undergone bowel resection with use of this test. No evidence of microscopic disease was found at the margins of the dissected specimens. The patients have been observed from seven months to one year and remain asymptomatic.
Lorenzo GA, Poticha SM, Beal JM. Mesenteric Lymphatics in Regional Enteritis. Arch Surg. 1972;105(2):375–378. doi:10.1001/archsurg.1972.04180080219037