Ultrasound of the Eye—Part 3: A Practical Guide to the Sonographic Anatomy of Emergent Ocular Pathologies

Vision threatening conditions require prompt assessment and timely treatment strategies. Ocular ultrasound is a useful diagnostic tool to complement the clinical examination. Its dynamic nature coupled with high accessibility and portability are advantages that are emphasised by its ability to provide a comprehensive assessment of the posterior segment when funduscopic examination is limited. Commonly, an obstruction to ocular light conducting media, or factors secondary to trauma and/or infection inhibit the clinical examination. The use of ocular ultrasound has also evolved to detect elevated intracranial pressure (ICP) through the measurement of widened optic nerve sheath diameter. To achieve positive patient outcomes, however, the operator must understand the sonographic appearances of ocular pathologies and acknowledge the potential differential diagnoses. As such, this article provides a comprehensive summary of emergent ocular conditions appreciated with ultrasound, the sonographic anatomy relative to each, and serves as a guideline for differentiating benign entities from those requiring urgent intervention.