Table 1.

Retinal imaging techniques.

Techniques	Pros	Cons
Color fundus photography (CFP)	Conventional historical	Low contrast
	Closely resembles clinical ophthalmoscopy	Experienced photographers and patient cooperation needed
	Documents a wide range of fundus abnormalities and AMD-associated phenotypic changes, particularly hemorrhages and focal pigmentary changes.	Difficulties in precisely delineating lesion boundaries/quantification of atrophic size
		Sensitive to optical media
Multicolor imaging	High contrast	Less distinct structures due to chromatic aberration
	Reveals details of different retinal layers	Poor distinction between hemorrhages and pigmentary lesions
Ultra-widefield (UWF)	Visualization of wide field of the retina	Developing tool
	Peripheral abnormalities visible	Limited data available
		Unknown clinical significance of peripheral lesions in AMD
Fundus fluorescein angiography (FA)	Visualization of retinal vasculature	Invasive procedures
	Gold standard for NV detection and quantification	Limited imaging window after injection
	Excludes presence of concurrent NV	Risk of life-threatening allergic reaction
	Sharper contrast between atrophic and surrounding non-atrophic areas.	Other lesions or leakage may obscure boundary demarcation of atrophy
		No visualization of choriocapillaris
Indocyanine green angiography (ICG-A)	Visualization of choroidal vasculature	Invasive procedures
	Choroidal imaging for differential diagnosis of PCV, RAP, CSR, Stargardt disease and nAMD	Limited imaging window after injection
		Risk of life-threatening allergic reaction
		Deep choroidal vessels may interfere with outline of area of atrophy
Fundus autofluorescence (FAF)	Non-invasive	Sensitive to optical media
	High contrast, good atrophic lesion boundary discrimination	Refractile (calcified) drusen at advanced stage are undetectable
	Quantification of RPE loss	Overestimates size of atrophic patch at macula
		Mask an atrophic area due to relative hypofluorescence of the fovea
		Unable to discern non-RPE layer features
Near-infrared reflectance (NIR)	Non-invasive	No validation studies in the detection of late AMD
	Unaffected by luteal pigment in foveal evaluation	Complements other imaging techniques
	High sensitivity for reticular pseudodrusen
	Not affected by optical media
Spectral-domain OCT (SD-OCT)/Swept-source OCT (SS-OCT)	Non-invasive	Scan field depends on optics used in the system
	Three-dimensional
	Detects morphology of retina layers, RPE, and choroid
	Detects early AMD features
Polarization-sensitive optical coherence tomography (PS-OCT)	Novel technique	No validation studies
	Assess RPE pigmentation
Optical Doppler tomography (ODT)	Quantitative imaging of vasculature	Still limited data available
	Functional detection
Phase contrast optical coherence tomography (PC-OCT)	Retinal microvasculature imaging	No consensus yet
Optical coherence tomography angiography (OCTA)	Non-invasive, no dye injection	Acquisition time and field when used with conventional OCT
	Three-dimensional images of vasculature
	Evaluation of choroidal layers
	Lower limitation in detecting slow blood flow
	Administered at any time

Abbreviations: AMD: age-related macular degeneration; CSR: chronic central serous chorioretinopathy; nAMD: neovascular AMD; PCV: polypoidal choroidal vasculopathy; RAP: retinal angiomatous proliferation. RPE: Retinal pigment epithelium.