Indigo Carmine unlike the vital stains (which are taken up by tissues), is not absorbed by gastrointestinal epithelium. It pools in crevices between epithelial cells, highlighting small or flat lesions and defining irregularities in mucosal architecture, particularly when used with high-magnification or high-resolution endoscopy.
It is used primarily in the colon for the detection and evaluation of colorectal neoplasia and is the most common form of chromoendoscopy applied in the colon. Indigo Carmine is used to evaluate pit patterns . These patterns can help discriminate between hyperplastic polyps (which have a typical “pit” pattern) and adenomatous polyps (which have a “groove” or “sulci” pattern) . Pit patterns can also aid in the diagnosis of minute, flat, or depressed colorectal tumors and increase the detection of flat adenomas . Indigo carmine can assist in the detection of dysplastic changes in patients with ulcerative colitis undergoing surveillance colonoscopy, as well as aid in the detection of adenomas in patients with hereditary nonpolyposis colorectal cancer.
Non-absorptive contrast stain for Chromoendoscopy: During continuous extubation, indigo carmine (0.4%) is gently applied to achieve diffuse coverage of the entire mucosal surface. Only a small volume of dye is applied to avoid excess dye accumulation. Re-examine after excess dye has been aspirated. Indigo carmine is easily applied using a special dye-spray catheter. Prior application of acetic acid has also been used in the upper gastrointestinal tract in some studies. An effective result can also be achieved by utilising the foot pump for spraying Indigo Carmine. See link below. NB: The stains used for Chromoendoscopy are transient, unlike the stains used to tattoo lesions
Polyp Delineation : To perform EMR a fluid is injected beneath the lesion to produce a sub-mucosal lift. A plasma expander is routinely used, as there is evidence to suggest that this lasts longer and leads to fewer resection pieces than saline. A small amount of adrenaline in the solution is used to avoid oozing and ensure a bloodless field. Indigo Carmine in the solution is used to stain the submucosa. The ideal solution should produce:
1) A long lasting high elevation
2) An avascular field
3) Good delineation of tissue planes
|PDYZ-0405||indigo carmine 5mL pre-filled syringe (box 5)|
|DYZ-0415||indigo carmine 15mL bottle (box 10)|