Ocular fluorometry: Principles, fluorophores, instrumentation, and clinical applications

Abstract

Ocular fluorometry is rapidly evolving as a versatile technique for research and diagnosis in ophthalmology. The main reasons for this increasing success are 1) the ideal characteristics of the eye as an optical device for excitation of tissue fluorescence and for the detection of the fluorescent emission; 2) the development of novel fluorometric techniques, including differential and time-resolved fluorescence spectroscopy; and 3) the increasing use of coupling geometries with high-resolution and high spatial selectivity. Both endogenous and exogenous fluorophores are of interest to ocular fluorometry. The most significant among endogenous fluorophores are the fluorescing pigments of the lens and of the retinal pigment epithelium (RPE). The nature, topography, and fluorescence properties of such pigments depend on age and pathology and on the level of light exposure. Exogenous fluorophores of interest are both intentionally induced and unintentionally accumulated drugs (some of which are phototoxic). Laser-based fluorometric techniques play a leading role in ocular fluorometry. The peculiar properties of the laser for the excitation of fluorescence make this source a favorite candidate for ocular fluorometry both in vitro and in vivo.

Autofluorescence methods in ophthalmology

“…As shown in previous studies, 26 the excellent sensitivity of the FM also makes it suitable for measuring autofluorescence of the ocular tissues. The system sends a focused excitation beam of blue light into the eye and then detects the resulting naturally fluorescent green light.…”

Characteristics of patients with a favorable natural course of myopic choroidal neovascularization

“…RPE function is affected in myopic eyes [8,11,20]. Aging is another factor that influences RPE function [4,5]. Thus, aged patients with high myopia are expected to have more widespread RPE dysfunction than younger patients.…”

Factors associated with the development of chorioretinal atrophy around choroidal neovascularization in pathologic myopia

“…RPE function is affected in myopic eyes [7,10,19]. Aging is also another important influence on RPE function [4,5]. Considering these factors, older patients with high myopia can be expected to have more widespread RPE dysfunction than younger patients with high myopia.…”