Table 1.

Criteria for histological scoring of intestinal biopsies after ischemic injury

					Evidence Regeneration Crypt Epithelium				Evidence Differentiation Crypt Epithelium
Classification	Surface Epithelium (% covered)	Villi (Contracted/Absent/Normal)	Percentage of Crypts Lined by Epithelium	Normal Crypts Epithelial Cells	Basophilic Cells	Loss Polarity	Cuboidal	Mitoses	Loss of Basophilia	Basal Polarity	Tall Columnar
Normal	90%–100%	Normal	95%–100%	Yes
Peracute	<25%	Contracted	>75%	Yes
Acute	<25%	Absent	<25%	No	No	No	No	No	No	No	No
Early regeneration	<40%	Absent	25%–80%	No	Yes	Yes	Yes	Prominent	No/rare	No/rare	No/rare
Late regeneration	>25%	Absent/blunted	>75%	No	No/rare	No/rare	No/rare	Rare	Yes	Yes	Yes