Ultrasound biomicroscopy

Ultrasound biomicroscopy (UBM) is a form of medical imaging that uses high-frequency ultrasound to produce detailed images of the microanatomy of the eye. It is particularly useful for visualizing the anterior segment of the eye, including the cornea, iris, ciliary body, and lens.

History

The development of UBM was driven by the need for a non-invasive method of imaging the anterior segment of the eye. The first UBM systems were developed in the late 1980s and early 1990s, and the technology has since been refined and improved.

Technique

UBM uses ultrasound frequencies of 35 to 50 MHz to produce images with a resolution of 25 to 50 micrometers. The high frequency of the ultrasound allows for detailed imaging of the anterior segment structures, but it also limits the depth of penetration to about 5 mm.

The patient is typically positioned supine and the eye is anesthetized with topical anesthetic drops. A small eyecup filled with saline solution is then placed on the eye to provide a medium for the ultrasound waves. The ultrasound probe is placed in the eyecup and images are obtained by moving the probe around the eye.

Applications

UBM is used in a variety of clinical settings, including the evaluation of glaucoma, cataract, corneal disease, and ocular trauma. It is also used in the preoperative assessment of patients undergoing refractive surgery and in the postoperative follow-up of patients who have had intraocular lens implantation.

Advantages and limitations

The main advantage of UBM is its ability to provide high-resolution images of the anterior segment structures. It is non-invasive and can be performed in the office setting. However, the technique requires a skilled operator and the images can be difficult to interpret. The depth of penetration is also limited, which can make it difficult to visualize deeper structures.

See also

• Ophthalmic ultrasonography
• Medical ultrasound