Confocal scanning laser ophthalmoscopy (cSLO) is the method for Heidelberg Retina Angiography (HRA). This method gives the patient comfort and safety by using low light exposure to produce a high resolution of the retinal and choroidal vasculature.

Confocality is used to create images with enhanced contrast, details, and sharpness. With a confocal aperture (pinhole) placed in front of the detector to block out-of-focus light, this method uses a focused laser beam to scan the retina point by point. With this configuration, only light from the focal plane reaches the detector, improving image contrast and the resolution.

By examining the retina point by point, the laser allows for the reconstruction of high-quality two-dimensional and three-dimensional pictures.

The Heidelberg retina angiograph (HRA) classic supports fluorescein angiography (FA) and indocyanine green angiography (ICG-A) of the retina and choroid.

The company's illustrious history in the design, production and sale of ocular diagnostic tools is complemented by its significant experience in the creation and use of sophisticated image and data management systems.

High-Resolution Imaging

Function: Provides crystal-clear views of the retina and choroid layers. Making it easier to detect even subtle eye problems that might go unnoticed with older imaging systems.

Fluorescein Angiography (FA)

Function: Uses a yellow dye to track blood flow through the retina and helps find leaking, blocked or swollen blood vessels, especially useful in diseases like diabetic eye disease and macular degeneration.

Fundus Autofluorescence (FAF)

Function: Captures the natural fluorescence of retinal tissue without the need for dye. Reveals early signs of damage to the retinal pigment layer, making it easier to catch diseases like AMD early.

Blue Reflectance Imaging (Red-Free)

Function: Uses a 488 nm blue laser to generate detailed, high-contrast images of the retinal nerve fiber layer. This technique is especially valuable for early diagnosis of glaucoma and detecting optic nerve abnormalities.

Confocal High-Contrast Imaging

Function: The HRA Classic uses confocal scanning laser technology to block scattered light, enhancing image clarity. It provides sharp, detailed images and enables optical sectioning, making it easier to distinguish between different layers of the retina.

Mostly supplied in Canada ophthalmic communities.

One of the largest optometric suppliers in Asia.

For simple acquisition and customization, the Heidelberg Spectralis HRA + OCT may be equipped with an external touch panel control and an optional panning camera headset. The system is capable of widefield and ultra-widefield imaging thanks to a number of image modules.

Also provide one system of HRA + OCT as this technology gives more benefits to users compared to the single one.

Trutrack Active Eye Tracking

The system uses two beams of light at the same time:

• The first beam scans and captures the retina while tracking over 1,000 points to monitor any eye movement.

• The second beam uses this tracking information to stay focused on the exact same area, even if the eye blinks or moves suddenly (saccades).

  • This feature is important when patients return for follow-up scans, the system can automatically scan the exact same area again, eliminating differences caused by the operator. It can detect and measure changes as small as 1 micron, making it ideal for monitoring disease progression or treatment response with great precision. This technology helps reduce errors, improves consistency, and saves time for optometrists.

The SPECTRALIS HRA-OCT is based on a Confocal Scanning Laser Ophthalmoscopy (cSLO) platform that is very sensitive to fluorescence to fluoresceine or ICG dyes. This offers excellent contrast and targeted imaging in still images or Heidelberg's special high speed imaging (videos).

Heidelberg Noise Reduction

• The system takes multiple images of the same area. It filters out random "visual noise" (unwanted speckles or static) and keeps only the parts that are consistent across all the images—which come from real, physical eye structures.

  • The result is a much clearer and sharper image with finer detail. It helps optometrists see tiny changes or structures in the eye more accurately, improving diagnosis and patient care.

Multicolor Imaging

• The SPECTRALIS MultiColor Module uses a special laser scanning method instead of regular white light and optics to capture detailed images of the retina. This technique uses three different laser wavelengths—blue, green, and infrared—at the same time to highlight different layers and structures in the eye.

  A study titled “Identifying features of early and late AMD” found that MultiColor imaging is more sensitive than traditional Color Fundus Photography (CFP) when detecting early signs of age-related macular degeneration (AMD), using data from 105 eyes.

  • High-resolution images are produced that highlight minute characteristics missed by fundus shots or routine eye exams. The pictures can be seen as a single color image or divided into separate images of infrared, green, and blue reflectance, each of which provides distinct information.

    • 🔵Blue reflectance: Ideal for observing surface-level alterations, like abnormalities in the nerve fiber layer or epiretinal membranes.

    • 🟢Green reflectance: Emphasizes exudates, blood, and vessels.

    • 🔴 Infrared reflectance: Displays deeper layers, such as the choroid and retinal pigment epithelium.
      

High-Resolution & High-Speed Imaging

• Provides dynamic video acquisition (up to 16 frames/sec) and image resolutions of up to 1536 × 1536 pixels. It makes early-phase angiography videos possible, which are ideal for spotting minute details like RCA/RAPs or feeder arteries.

• Retinal and choroidal diseases can be seen in three dimensions due to optical sectioning (64 focus planes) and high resolution (5 μm).
  

Stereo and 3D Imaging Quickly

• It captures stereo picture pairs without requiring the patient to move or feel uncomfortable by light flashes.

• Clear 3D reconstructions are made possible by depth scanning of up to 8 mm, which is particularly useful for cancers like choroidal melanomas.
  

Low Light Exposure - Enhanced Patient Comfort

• The HRA 2 uses precise laser scanning instead of bright flashes, reducing light exposure to just 1% of what traditional fundus cameras require.

• This makes the procedure safer and far more comfortable, especially for patients who are sensitive to light, such as children or those with eye conditions.

Indocyanine Green Angiography (ICGA)

Function: Uses a near-infrared dye to image blood vessels deep beneath the retina. Ideal for diagnosing issues like hidden choroidal conditions and tumors that can’t be seen with fluorescein alone.

The technique that used in HRA is confocal Scanning Laser Ophthalmoscopy (cSLO).

A laser beam spreads the fundus in a raster pattern, illuminating consecutive retinal components point by point at speeds of up to 24 milliseconds.

A confocal aperture is placed in front of the image detector at a focal plane that corresponds to the retina. The aperture filters out non-image-forming light to reduce scatter and chromatic aberration.

A photomultiplier captures the light that each retinal spot reflects. The photomultiplier's output is recorded and shown as digital video.

As a result, tiny vessels that were previously undetectable in white flash light photography are now visible in remarkable detail. Unlike standard fundus cameras, the cSLO lacks an optical viewfinder, making aerial-image focusing easier.