Learning objectives
To go into detail about ABER tecnique is performed and its anatomic interpretation
Background
The additional sequence with the patient's arm ABducted and Externally Rotated (ABER view) in MR arthography exam,
can enhance interpretive and diagnostic accurancy for labral and rotator cuff tendons patology.
Fig. 1 Fig. 2
This position stresses the anteroinferior glenohumeral labroligamentous complex and releases tension on the cuff relativa to the normal coronal view obtained with the arm in adduction.
This reduced tension anables intraarticular contrast material to flow into any defect,
increasing the diagnosis of partial thickness tears.
Despite the benefits of ABER sequence,...
Imaging findings OR Procedure Details
The true ABER position (90° of abduction and 90° of flexion of the arm) is not possible with closed-bore MR scanners.
After conventional MR sequences are developed,
patient is relocated in ABER position,
with the hand placed behind the head or neck and the elbow flexed.
Fig. 3
A coronal localizer sequence is acquired.
Repeat this step to make sure that scout images are passing through the glenohumeral joint space,
if it’s required Fig. 4
Axial oblique ABER images will be perpendicular to the glenoid...
Conclusion
An additional sequence done with the arm in abduction and external rotation (ABER) has been useful in explaining equivocal findings or making diagnoses not detected on conventional positions in shoulder MR arthrography.
Nevertheless some patients cannot keep ABER position secondary to pain and adding an extra sequence prolongs examination time
In our experience,
the total additional time for ABER positioning and scanning is only 5 minutes and the use of some anatomic landmarks enhances understading
The ABER view is an excellent tool for detecting anteroinferior...
References
Jin Young Jung,
Doo Hoe Ha,
Sang Min Lee,
Marcia F.
Blacksin,
Kyung Ah Kim,
Jae Wha Kim.
Displaceability of SLAP lesion on shoulder MR arthrography with external rotation position Skeletal Radiol.
2011; 40:1047–1055
Tirman P,
Bost F,
Steinbach L,
et al.
MR arthro- graphic depiction of tears of the rotator cuff: benefit of abduction and external rotation of the arm.
Radiology 1994; 192:851–856
Cvitanic O,
Tirman P,
Feller J,
et al.
Using abduction and external rotation of the shoulder to increase the sensitivity of...