Relationships between Visual Field Sensitivity and Spectral Absorption Properties of the Neuroretinal Rim in Glaucoma by Multispectral Imaging

Abstract

Residual NRR DLA is related to VF sensitivity in POAG. Multispectral imaging may provide clinically important information for the assessment and management of POAG.

The Future of Imaging in Detecting Glaucoma Progression

“…MSI has also been used to measure increased venular retinal oxygen saturation in POAG compared to healthy subjects (70). Measurements using MSI have illustrated differential light absorption in neuroretinal rim tissue that is associated with visual field sensitivity in POAG (71). …”

Differences in spectral absorption properties between active neovascular macular degeneration and mild age related maculopathy

“…Several research groups have used such techniques to assess light absorption properties in retinal blood vessels and peripapillary retina 1–3. Denniss et al 4 investigated the light absorption properties of the neuroretinal rim using a metric of differential light absorption (DLA), based on the Beer-Lambert model of light absorption. The nature of this parameter (DLA) has been explained in detail in a previous publication 4.…”

“…Denniss et al 4 investigated the light absorption properties of the neuroretinal rim using a metric of differential light absorption (DLA), based on the Beer-Lambert model of light absorption. The nature of this parameter (DLA) has been explained in detail in a previous publication 4. Briefly, DLA is a measure of the relative wavelength-specific, light absorption properties of imaged tissue which depends on the concentration of wavelength-specific absorbers in the tissue.…”

“…This measure was originally developed to correspond with information on relative concentrations of oxyhaemoglobin and deoxyhaemoglobin, but has no such validated correspondence when applied to macular imaging, and thus is presented in this study simply as a methodical and standardised function of the light absorption properties of the tissue. In the current study, we applied the same camera and techniques used by Denniss et al 4 to retinal tissue imaging in order to compare DLA in maculae of eyes with active neovascular disease to their fellow eyes with early age related maculopathy (ARM).…”

“…A low-noise, Peltier-cooled charged coupled device array (Orca C4742-80-12AG; Hamamatsu Photonics, Hamamatsu, Japan) with a spatial resolution of 336×256 pixels was used for image capturing. This system can be used to illuminate the retina with almost any chosen wavelength 4. Sequential wavelengths between 496 and 700 nm were used for imaging and each complete eye scan lasted less than 1.6 s. The 570 nm wavelength corresponds to the isosbestic point (defined in spectroscopy as a specific wavelength at which two chemical species, in this case oxyhaemoglobin and deoxyhaemoglobin, have the same molar extinction coefficients) for light absorption between oxygenated and deoxygenated haemoglobin in water whereas at wavelengths between 570 and 700 nm the ratio between absorption by oxygenated and deoxygenated haemoglobin is large.…”