(c)  

Ultrasound biomicroscopy
Study	Location	Year	Study design	Number of eyes	Major findings
Char et al. [23]	United States	2002	Prospective case series	SCC (4)	20 MHz high frequency ultrasound demonstrates deep involvement of tumor into the sclera, globe, or orbit and is a useful tool for tumors with deep invasion. It is of otherwise limited utility in tumors without deep extension.
Finger et al. [11]	United States	2003	Retrospective case series	Conjunctival intraepithelial neoplasia and SCC (11)	20 and/or 50 MHz high frequency ultrasound helps delineate tumor thickness, shape, and internal reflectivity and is particularly helpful in determining if the tumor has extended into the sclera, eye, and orbit.