Role of ultrasound biomicroscopy in corneal, conjunctival lesions and related anterior segment comorbidities

Ultrasound biomicroscopy (UBM) is a high-frequency ultrasound imaging modality that aids in the visualization of anterior segment structures as far back as the ciliary body. It was a popular modality for corneal imaging until the advent of anterior segment optical coherence tomography (AS-OCT) a decade ago. While the higher resolution of AS-OCT has enhanced the diagnostic accuracy of corneal and conjunctival disorders by providing excellent anatomical and structural details, its role is limited in cases of dense, compact, and pigmented lesions, and imaging structures like zonules and ciliary body due to limited penetration. In these eyes, UBM scores over AS-OCT by providing superior structural details. This review explores the role of UBM as a primary investigative modality in corneal, conjunctival, and allied comorbidities and also highlights how it aids preoperative assessment and surgical planning.