Table 1.

Narrowband imaging (NBI) International Colorectal Endoscopic (NICE) Classification^∗

	Type 1	Type 2	Type 3
Color	Same or lighter than background	Browner relative to background (verify color arises from vessels)	Brown to dark brown relative to background; sometimes patchy whiter areas
Vessels	None, or isolated lacy vessels may be present coursing across the lesion	Brown vessels surrounding white structures∗∗	Has area(s) of disrupted or missing vessels
Surface pattern	Dark or white spots of uniform size, or homogeneous absence of pattern	Oval, tubular or branched white structures∗∗ surrounded by brown vessels	Amorphous or absent surface pattern
Most likely pathology	Hyperplastic & sessile serrated polyp (SSP)∗∗∗	Adenoma∗∗∗∗	Deep submucosal invasive caner

NICE, NBI International Colorectal Endoscopic Classification.

^∗Can be applied using colonoscopes with/without optical (zoom) magnification.

^∗∗These structures (regular or irregular) may represent the pits and the epithelium of the crypt opening.

^∗∗∗In the WHO classification, sessile serrated polyp and sessile serrated adenoma are synonymous. SSPs often demonstrate some dark, dilated crypt orifices.

^∗∗∗∗Type 2 consists of Vienna classification types 3,4, and superficial 5 (all adenomas with either low or high grade dysplasia, or with superficial submucosal carcinoma). The presence of high grade dysplasia or superficial submucosal carcinoma may be suggested by an irregular vessel or surface pattern, and is often associated with atypical morphology (e.g. depressed area).