The objective of this study is to image retinal vascular alterations in patients with
retinal disease using the AngioVue OCT-A system and understand the information these images
provide. The investigators will image study participants who have retinal diseases with the
AngioVue unit (Optovue) and will collect relevant clinical data to understand the nature of
the information contained in images obtained on AngioVue. This study being conducted under
an abbreviated IDE. The investigators will analyze data using descriptive statistics. Risks
related to light exposure will be managed by ensuring that the exposure to the AngioVue
light source is well below maximum permissible limits for safe exposure.
OCT is an optical ranging and imaging technique first described in 1991 that has since been
used successfully to provide high-resolution, micrometer-scale depth imaging in clinical
ophthalmology (and other fields). It can be thought of as the optical analogue of ultrasound
imaging. For the ocular posterior segment, OCT provides rapid acquisition of
high-resolution, cross-sectional images of the retina that approximate tissue histology. In
vivo imaging of the retina with OCT has thus dramatically improved clinicians' diagnostic
capabilities, allowing earlier and more accurate diagnosis of disease and more precise
assessment of response to therapies over time.
While OCT provides important information on retinal anatomy, it is currently limited in its
ability to provide information on retinal vasculature and blood flow. Angiography is the
current gold-standard imaging modality for retinal vascular imaging. Angiography involves
intravenous injection of a fluorescent dye (typically either fluorescein or indocyanine
green for the retinal or choroidal vessels, respectively) that circulates through the body.
A light source emitting light at the specific excitation wavelength of the dye is placed in
front of the patient's eye, and a camera equipped with a filter corresponding to the
emission wavelength of the dye is then used to image vessel morphology and retinal
perfusion, either through still images or through a short movie. Angiography provides
physiologic information about the retina that complements the anatomical information
provided by OCT. While generally well tolerated by most patients, angiography does have
drawbacks: it often requires the use of a separate imaging system, it requires several
minutes for image acquisition, and it involves intravenous injection of a dye. Patients
occasionally experience side effects of intravenous dye administration, including nausea,
discomfort, and rarely, anaphylaxis.
Several retinal imaging companies are developing the next generation of OCT technology: OCT
angiography (OCT-A). OCT-A allows noninvasive, high-resolution imaging of the
microvasculature of the retina and choroid (the vascular plexus subjacent to the retina),
without the need for intravenous dye administration. OCT-A platforms currently under
development include both spectral domain (SD) and swept-source (SS) based technologies.
Whereas SS-based OCT-A utilizes a longer wavelength (~1060 nm) light source, SD-based units
use the same light source used in commercially available and FDA-cleared OCT units on a
modified platform. Optovue, Inc. (Fremont, CA) has developed one such unit, a customized,
high-resolution SD-OCT system that implements a novel algorithm, the amplitude-based method
of split-spectrum amplitude-decorrelation angiography (SSADA) for OCT-A. This SSADA
algorithm allows for detection of motion in the blood vessel lumen by measuring the
variation in reflected OCT signal amplitude between consecutive cross-sectional scans.
Optovue has integrated the novel SSADA algorithm into their commercially approved RTVue
SD-OCT unit for their OCT-A unit, the AngioVue. The AngioVue can generate high-quality
angiograms of both the retina and choroid. Additionally, this refined method has produced
images of the smallest retinal vessels (capillaries) in normal healthy control participants.
In this proposed prospective interactive clinical study, we will use the AngioVue unit to
image patients and characterize vascular abnormalities that are present in the setting of
- Capable and willing to provide consent
- History of clinically diagnosed retinal diseases, including but not limited to
age-related macular degeneration, diabetic retinopathy, retinal vein occlusion,
macular telangiectasias, and diabetic macular edema
- At least 18 years of age
- Unable or unwilling to give consent
- Under 18 years of age