Assessment of capsular block syndrome with anterior segment optical coherence tomography.

A 59-year-old woman developed progressive, moderate myopia 1 year after routine phacoemulsification and insertion of a soft posterior chamber intraocular lens (IOL). After biomicroscopy, late capsular block was diagnosed and treated with a neodymium:YAG laser posterior capsulotomy. The myopia disappeared immediately. This case was illustrated using optical coherence tomography developed for the anterior segment. After capsulotomy, the IOL moved backward by 448 microm, corresponding to -0.75 diopter of induced myopia.

Static and dynamic analysis of the anterior segment with optical coherence tomography.

PURPOSE: To study biometric modifications of the anterior segment with accommodation and age and determine possible applications in areas of anterior segment surgery, particularly implantation of refractive lenses. SETTING: Clinique Monticelli, Marseille, France. METHOD: The study comprised subjects between 7 years of age and 82 years of age in whom anterior chamber biometry was evaluated using 1,310 nm wavelength optical coherence tomography (OCT). The equipment has a fixation target that can be focused and defocused with negative lenses to stimulate natural accommodation. All measurements were performed by the same operator. The horizontal diameter of the AC, the anterior chamber depth (ACD), the horizontal pupil diameter, and the horizontal radius of curvature of the crystalline lens' anterior pole were measured in the unaccommodated state and after stimulating accommodation. RESULTS: Fifty-six subjects (104 eyes) were included; the refractions ranged from +5.0 diopters (D) to -5.0 D. The static and dynamic measurements were compared with ametropia, age, and accommodation. At rest, the mean AC diameter was 12.334 mm, the mean ACD was 3.106 mm, and the mean pupil diameter was 4.258 mm. With 1.0 D of accommodation, the anterior pole moved forward by a mean of 30 microm, the radius of curvature decreased 0.3 mm, and the pupil diameter decreased 0.15 mm. CONCLUSIONS: The AC OCT is a user-friendly instrument for evaluating the anterior segment and examining the AC (cornea, iris, crystalline lens, and iridocorneal angle). The 1,310 nm light wavelength is blocked by pigments, preventing examination behind the iris. However, the AC OCT is capable of good image quality and visualization of the anatomical relationships in the anterior segment, even behind an opaque cornea.

Contact between 3 phakic intraocular lens models and the crystalline lens: an anterior chamber optical coherence tomography study.

Three phakic intraocular lens (IOL) models were implanted in 3 different patients. With the usual slitlamp examination, it was not possible to determine whether there was contact between the IOLs and the natural crystalline lens. Using the anterior chamber optical coherence tomography (AC OCT) scanner, direct contact between the natural crystalline lens and the 3 phakic IOLs was revealed. A dynamic study of the contact was performed during accommodation. These observations show that examination of the anterior segment with the AC OCT scanner provides new data about the status of the anterior segment after implantation of phakic IOLs.

Anterior chamber optical coherence tomography study of human natural accommodation in a 19-year-old albino.

Anterior segment optical coherence tomography is a new method to explore the anterior chamber. The target can be focused and defocused with positive or negative lenses to reproduce the conditions of natural accommodation. We studied accommodation in an albino patient because the absence of pigment allows the infrared beam to penetrate the iris and explore the modifications of the ciliary body and the crystalline lens during natural accommodation in a human subject.