A recently released ultra-widefield fundus camera takes images in true color and captures high-resolution imagess rom the macula to the far periphery.
Reviewed by Roger Goldberg, MD
A newly released high-definition (HD) ultra-widefield fundus imaging system (CLARUS 500, Carl Zeiss Meditec) enables clinicians to capture images of higher quality and resolution from a significantly larger area than traditional fundus cameras.
The approach in designing the system was to provide the clinician the widest field of view with excellent clarity and color.
One of the most important features of the new camera is that it captures images in natural color, closely resembling the color seen when examining the patient.
It uses the full spectrum of light, incorporating three broad-spectrum LEDs-red, green, and blue-which makes it possible to get true color imaging. This true color allows for more clear views of the retina and retinal pathology.
Another important feature is the resolution at any point on the image. The camera captures a high-resolution image down to 7 μm, which allows a user to zoom in anywhere on an image without losing quality.
The system allows clinicians to zoom into any area and expand the entire screen to display it. The images are non-pixelated and can be compared with the quality of a traditional non-widefield fundus camera.
Clinicians also benefit from having one device that provides ultra-widefield imaging for evaluating a broad range of patients, and to have one device provide high resolution-to track the progression of their glaucoma patients, as an example.
“You can zoom in, and you’ve got a true-color, high-resolution photo of the macula, the optic nerve, a nevus, or whatever it is you’re trying to document,” said Roger Goldberg, MD, Bay Area Retina Associates, Walnut Creek, CA.
Different from fundus camera
Dr. Goldberg has compared the images from the new system to those taken with traditional fundus cameras, and said he found that the quality is as good as, or even better than, traditional fundus photos.
“You’re not compromising anything on your traditional fundus photography in order to get the widefield view,” he said.
The camera produces a 133° HD widefield image with one click. Two HD widefield images are automatically merged to achieve a 200° ultra-widefield view. The system’s internal fixation can be placed anywhere within the patient’s field of view to target specific parts of the retina.
The design of the system was aimed at making things easier and more comfortable for the patient, and more convenient for a photographer or technician than previous ultra-widefield imaging systems.
Previously released imaging systems involved a stationary camera and a patient would need to be moved into the optics, with the operator adjusting the patient’s head to move the eye into the focal point of the camera.
With the ultra-widefield camera, the patient sits down and puts their chin against a chin rest, and their forehead against the bar at the top, and the operator aligns the camera to the patient to focus and acquire the image.
Another feature of the camera involves a live infrared preview of the fundus before the picture is taken to show what is about to be captured. Since the image is infrared, it is not uncomfortable for the patient.
This allows the photographer to confirm the image will be captured as desired, and avoid artifacts or poor quality images, which results in fewer re-captures or attempts to photograph each eye.
Because this system incorporates ultra-widefield imaging with true color and high resolution fundus imaging, it may eliminate the need to have a different camera for each of those purposes, saving on space and costs, and improving efficiency.
The images from the system are also fully supported by the company’s management system for integrating the device in a practice.
The system doesn’t currently have capabilities for fluorescein angiography or ICG, but these are planned as future upgrades.
Roger Goldberg, MD
Dr. Goldberg receives research grants, equipment, and consulting fees from Carl Zeiss Meditec.