PERIANAL/PERIRECTAL FISTULA OR ABSCESS(last updated 11/13/2020, last reviewed 02/10/2022)
INDICATION: Perianal fistula, Crohn's.
SEQUENCES
Ax HASTE whole pelvis
Cor HASTE whole pelvis
Ax fat sat TSE T2 small FOV rectum, anus, perineum (small FOV ~22cm)
Cor fat sat TSE T2 small FOV rectum, anus, perineum
Sag fat sat TSE T2 small FOV rectum, anus, perineum
Ax T1 small FOV rectum, anus, perineum
Ax 3D VIBE (fat sat) small FOV rectum, anus, perineum pre
Ax 3D VIBE (fat sat) small FOV rectum, anus, perineum post
Cor 3D VIBE (fat sat) small FOV rectum, anus, perineum post
Sag 3D VIBE (fat sat) small FOV rectum, anus, perineum post
Subtraction images
| ST. JAMES UNIVERSITY MR CLASSIFICATION (imaging) |
0
|
Normal
|
1
|
Simple linear intersphincteric fistula
|
2
|
Intersphincteric fistula with intersphincteric abscess or secondary tract
|
3
|
Trans-sphincteric fistula
|
4
|
Trans-sphincteric fistula with abscess or secondary tract within ischioanal or ischiorectal fossa
|
5
|
Supralevator or translevator disease
|

Grade 1

Grade 2

Grade 3

Grade 4

Grade 5

Parks Classification (surgical)
A intersphincteric
B transsphincteric
C suprasphincteric
D extraspincteric