Purpose: To evaluate the role of high resolution B-scan echography in differentiating the causes of optic disc excavation. Methods:  A prospective study was conducted on 30 subjects presenting to Al-Zahraa University Hospital (2009 – 2011) with optic nerve excavation.  Of these patients 10 with coloboma, 10 with cup-shaped posterior staphyloma and 10 with glaucomatous optic nerve cupping were identified. Horizontal and vertical approaches for optic disc excavations were evaluated using B-scan echography. Specific echographic criteria for excavation configurations were successfully estimated. Results & conclusion: High-resolution contact B-scan echography may provide useful differentiation for optic disc excavations in eyes with opaque media.