Optic Disc and Nerve Fiber Layer

Other imaging techniques that utilize different physical properties of light for optical analysis can document the status of the optic nerve and the nerve fiber layer. Furthermore, they can be used to detect changes over time (Medeiros et al., 2004). The value of these technologies for diagnosing glau- 

Confocal scanning laser ophthalmoscopy can evaluate the optic disc and peripapillary retina in 3 dimensions and provide quantitative information about the cup, neuroretinal rim, and contour of the nerve fiber layer. 

Scanning laser polarimetry measures the change in the polarization state of an incident laser light passing through the naturally birefringent nerve fiber layer to provide indirect estimates of peripapillary nerve fiber layer thickness. 

Optical coherence tomography uses reflected light in a manner analogous to the use of sound waves in ultrasonography to create computerized cross-sectional images of the retina and optic disc, and also gives quantitative information about the peripapillary retinal nerve fiber layer thickness. 

Fluorescein angiography, ocular blood flow analysis via laser Doppler flowmetry, color vision measurements, contrast sensitivity testing, and electrophysiological tests (e.g., pattern electroretinograms) are used as research tools in the evaluation of POAG patients. Routine clinical use is not advocated at this time. 

---