The following picture is the post-mortem specimen of anterior segment.

What does the picture show?

Answer
Soemmering's ring.
 

What is the mechanism for its formation?

Answer
The ring occurs when there is a break in the anterior capsule 
resulting in trapping of cortical material in the equatorial regions. 
The ring has a doughnut configuration.
 

Suggest two possible causes in this specimen.

Answer
Incomplete removal of cataract.
Trauma