a. Referring to the picture above. Name the structures labelled a-d as 
    seen through a gonioscopic lens.

b. Referring to the picture above. Name the abnormal sign in this 
    gonoscopic view. Name two conditions in which this sign can occur.

 
Answer a
a. Schwalbe's line.
b. Trabecular meshwork.
c. Scleral spur.
d. Ciliary body.
 

Answer b
Sampaolesi 's line (a ring of pigment located along Schwalbe's line and anteriorly).
This is seen in:
pigment dispersion syndrome
pseudoexfoliation syndrome
trauma
iris melanoma