Anterior segment optical coherence tomography (AS-OCT) is a non-contact imaging modality, which
was developed to obtain cross-sectional images of anterior segment structures including the angle.The advantages
of AS-OCT over more traditional methods of examining the angle such as gonioscopy and ultrasound
biomicroscopy (UBM) are that it is quick, non-invasive and requires less skill to acquire and interpret images.
The current roles of AS-OCT imaging include confirmation of the diagnosis of angle closure and measurement of
change in angle width following laser or surgical interventions for angle closure.In regions of the world where
angle closure glaucoma is prevalent, AS-OCT has potential as a future screening method for the disease.Currently
this technology is limited by having difficulty in identifying important landmarks in the angle due to suboptimal
image quality in many cases. This results in apparent over detection of angle closure when compared with
gonioscopy and difficulty in applying quantitative measurement parameters in image analysis. Rapid
developments in imaging technology including fourier domain OCT and 3-dimensional OCT may help overcome
some of these limitations.
Keywords: Anterior segment optical coherence tomography, ultrasound biomicroscopy, angle closure, anterior
chamber angle, trabecular meshwork, laser peripheral iridotomy, gonioscopy, peripheral anterior synechiae, iris,
lens, glaucoma.
