Table 1: Niemeier classification:

types of gallbladder perforation.

Type

Features

1

Chronic perforations: the fistulous tract is seen between the gallbladder and some other viscera

2

Subacute perforations: the gallbladder is surrounded by an abscess and adhesions in the peritoneal cavity

3

Acute perforation: free perforation into the abdominal cavity