Ultrasound biomicroscopy is a high-frequency ultrasound technique that provides detailed cross-sectional images of the anterior segment structures, including the cornea, angle, iris, and ciliary body. It offers higher resolution than standard B-scan for shallow structures.
Technique
A small probe operating at very high frequency is placed close to the eye, often with an immersion bath or coupling medium. The resulting images display fine anatomical details at depths of only a few millimetres.
- Useful when optical methods are limited by opacity or extreme anatomy
- Shows sulcus, ciliary body, and posterior chamber structures clearly
- Can be performed in both phakic and pseudophakic eyes
- Requires patient cooperation and careful technique
Clinical Uses
Ultrasound biomicroscopy is used to evaluate narrow angles, plateau iris, cysts, tumours, and positioning of intraocular lenses or drainage devices. It helps clarify mechanisms of angle closure and guides surgical planning.
- Provides objective measurements of angle configuration and lens position
- Can reveal occult pathologies not visible on gonioscopy
- Serial studies monitor changes after interventions
- Interpretation should be integrated with clinical findings and other imaging
