The TRC-NW8F Plus: As a multi-function retinal camera, the TRC- NW8F Plus captures color, red free, fluorescein

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1 The TRC-NW8F Plus: By Dr. Beth Carlock, OD Medical Writer Color Retinal Imaging, Fundus Auto-Fluorescence with exclusive Spaide* Filters and Optional Fluorescein Angiography in One Single Instrument W ith the release of the TRC-NW8F Plus, Topcon is introducing an all-in-one retinal imaging system by incorporating it s exclusive Spaide* filters that enable this camera to capture fundus auto-fluorescence (FAF), in addition to color, red-free and FA images. Figure 1: Color Retinal Imaging, Fundus Auto-Fluorescence with exclusive Spaide* Filters and Optional Fluorescein Angiography in One Single Instrument Product Overview The TRC-NW8F Plus camera includes illumination, alignment, focusing and fixation characteristics. Near infrared light is used for alignment and positioning. A pair of reflected spots of light acts as a positioning aid (working distance spots). Focusing is performed automatically and a pair of vertically sliding lines tells the operator when the sharpest focus has been achieved. Patient fixation is achieved by nine internal LED targets positioned in a circular fashion to allow several fixation patterns. As a multi-function retinal camera, the TRC- NW8F Plus captures color, red free, fluorescein angiography (FA) and fundus auto fluorescence (FAF) images. Conveniently, the color, red free and FAF images can be obtained without the use of mydriatic drops. The inclusion of a selectable exciter and barrier FA filters in the acquisition path permits the instrument to acquire high resolution angiography images that include a time stamp, eye and angle of capture. A 16.2 megapixel digital camera back, standard in the TRC-NW8F Plus, ensures sharp, highquality images of the central 45 degrees of the retina, including the fovea, macula and main vessels when used with the central fixation target, as well as peripheral views of the retina when used with the adjustable internal fixation targets allowing 9 different positions. The TRC-NW8F Plus includes automatic focus and capture in conjunction with a small pupil detection feature that simplifies its use even by minimally trained staff. Figure 2: Near infrared light is used for alignment and positioning. A pair of reflected spots of light acts as a positioning aid. With the TRC-NW8F Plus built-in LCD color monitor, it is possible to view the images before they are displayed and saved in the optional capture software. Another advantage of the TRC- NW8F Plus is the seamless interface with various digital capture programs. The TRC-NW8F Plus is fully compatible with all Topcon IMAGEnet Capture Software and Synergy Image Management Systems, allowing all data captured to be stored and accessed and manipulated as needed in the capture computer or in any review station.

2 The TRC-NW8F Plus provides high quality images right on the camera monitor facilitating the selection of the pictures before they are saved to the capture system. Image quality and resolution are of great diagnostic importance, because there is a need to obtain sufficient detail for retinopathy grading and adequate field definition, which shows the desired area of view (disc and macula). An indicator of the instrument s image quality is the visibility of macular vessels and vessel crossing. The TRC-NW8F Plus non-mydriatic retinal camera is easy to use and convenient for patients and operators alike, saving time and enhancing work flow. Fluorescein Angiography (FA)** FA requires the use of a fundus camera equipped with excitation and barrier filters. The TRC- NW8F Plus is equipped with the latest generation of FA filters, yielding excellent images with good contrast. **Optional function Figure 3: The Topcon TRC-NW8F Plus is equipped with the latest generation of FA filters, yielding excellent images with good contrast. The FAF Function Fundus auto fluorescence (FAF) imaging is a relatively recent imaging method to observe and document lipofuscin distribution in the retinal pigment epithelium that may occur during the onset of disease in the outer retina and the sub neurosensory space. Excessive accumulation of lipofuscin granules in the retinal pigment epithelium cells characterizes a common pathogenesis conduit in various genetic retinal diseases, including age-related macular degeneration (AMD). FAF imaging has been useful in understanding physiologic mechanisms, diagnostics, identification of disease progression, and monitoring of new therapies. FAF imaging provides more information than obtained by conventional imaging methods, such as fundus photography, fluorescein angiography, and optical coherence tomography (OCT). Its clinical value together with its simple and noninvasive nature is increasingly gaining acceptance in the ophthalmic community. (1) FAF has been used in ophthalmology for many years. Auto fluorescence was first identified through control shots or images taken prior to fluorescein injection in FA studies. In those early images, the optic nerve head and macular drusen were seen clearly. However, macula pathology was rarely seen, and not clearly understood. *Several years ago, Dr. Richard Spaide undertook research on auto fluorescence to develop the ideal set of photographic filters that would yield the best results. Specifically, his investigation focused on altering filter characteristics to better visualize fundus auto fluorescence. Lipofuscin has a peak emission between nm; whereas fluorescein has a peak emission between nm. Thus FA filters were not matched to visualize lipofuscin. Early FAF imaging required much exposure, did not provide good detail and was not optimized. Dr. Spaide has optimized FAF filter characteristics to get significantly better images. These filters are optimized for lipofuscin, and they require 40% less flash intensity which benefits the patient by increasing comfort and minimizing the risk of photo toxicity. Additionally, these filters do not stimulate fluorescein or indocyanine green so images can be taken during or post angiography. These filters also increase the contrast of lipofucin deposits making them visible even in darker areas of the retina. Engineers at the factory optimized the Spaide filters to fit Topcon

3 Figure 4: Fundus auto fluorescence (FAF) images and corresponding grey scale values in a normal subject. Dr. Spaide has optimized FAF filter characteristics to get significantly better images. retinal cameras such as the TRC-NW8F Plus. Spaide Filters are today the standard for fundus auto fluorescence worldwide, and they are exclusive to Topcon. Figure 5: Spaide Filters are today the standard for fundus auto fluorescence worldwide, and they are exclusive to Topcon. ENHANCED FEATURES The TRC-NW8F Plus is a non-mydriatic camera that consistently provides good quality imaging combined with faster capture and improved ease-of-use. Key features of this system include: High-resolution, 16.2 megapixel CMOS sensor as standard. This feature allows users to obtain excellent quality images that can be analyzed and enlarged with minimal loss of quality. Compatible with Topcon s IMAGEnet 5 Digital Imaging System, which provides image capture, saving and manipulating capabilities. When used with IMAGEnet 5, the TRC-NW8F Plus images that are captured with the instrument can be displayed on a computer monitor and saved to local or remote locations and servers. In addition, IMAGEnet software allows enhancement and correction of the images contrast and color balance. Figure 6: Compatible with Topcon s IMAGEnet 5 Digital Imaging System, which provides image capture, saving and manipulating capabilities. Color and FA images only

4 Additionally, IMAGEnet 5 is fully compliant with the Digital Imaging and Communications in Medicine (DICOM) which allows you to store images to a remote server, or to an electronic medical records systems (EMR). Automatic focusing and automatic capture, making the system easier to use even for operators with minimal training. The controls are intuitive and marked with easy to understand icons for user s convenience. Although the system offers easy alignment, auto-focus and auto-capture, the operator remains in control at all times during the imaging process and can, if necessary, override the automatic features. Figure 7: The auto focus automatically captures the image when the split lines turn green. The most common artifacts arising from over exposure are excessively bright areas that show little or no detail, such as the head of the optic nerve or reflective scar tissue areas. Artifacts from under exposure are typically dark areas in the center or periphery of the retinal image, along with lack of detail in the darkened areas, as well as detail missing from entire sections of the image. The TRC-NW8F Plus features an easy-to-use flash adjustment that provides four steps of intensity above and below the default value. This feature makes it easier to avoid these types of artifacts by decreasing or increasing the flash intensity. Additionally the default value can be adjusted from the menu to suit a specific patient population such as diabetics or patients with glaucoma. The system has an automatic small pupil detection mode, which switches to a small pupil diaphragm in patients who have small pupils (>3.3-mm) or in those that cannot tolerate mydriatic drops. Equipped with a high resolution sensor, the TRC NW8F Plus is also capable of adjusting the amount of flash illumination that is necessary to capture an image -- this translates into improved comfort and better patient acceptance to being photographed. The automatic feature of the instrument speeds up the capture process and minimizes patient time at the camera. Figure 8: The high resolution sensor provides excellent quality images in color and black and white. TRC-NW8F Plus In the Market Place Clearly, there are many different options to choose from when considering an investment into a new retinal imaging system. What sets the TRC-NW8F Plus apart from other non-mydriatic retinal cameras is its ease of use and automated functions. Since it is also supplied with the Spaide FAF filters images have more detail than conventional filters. Consequently, there are fewer artifacts in the images, mak-

5 ing the TRC-NW8F Plus approximately 20 times more efficient than previous-generation FAF filters. It also requires 40% less flash intensity thus improving patient comfort. In addition, while all retinal cameras are capable of capturing individual images that can be combined into a stereoscopic pair, the TRC-NW8F Plus features a function that allows for capturing two successive images by automatically shifting the internal fixation target. This enables the camera to obtain a stereo pair of images that can be viewed in 3D by using a stereo viewer. TRC-NW8F Plus Myd/Non-Myd Retinal Camera Abnormalities beyond the photographic field Even though the TRC-NW8F Plus can cover a large area of the retina when using the peripheral fixation targets, the primary use of the system, as with any other retinal camera, is to document the findings of a dilated exam and make the results available for comparison, reporting or teaching. Because the TRC- NW8F Plus has specific internal electronics for use in telemedicine, as well as use with the IMAGEnet system, sharing the photographic findings of the camera is straightforward and user-friendly. Since the introduction of its first retinal camera in 1965, Topcon has built a leadership position in the field of retinal photography. The introduction of the TRC-NW8F Plus once again provides clinicians with enhanced capabilities increasing the functionality of the device by providing a full range of retinal imaging, including true red free, fluorescein angiography and fundus auto-fluorescence photography, with minimal training required. References Color, FA, and FAF Ease of Use 1. Fundus auto fluorescence imaging: review and perspectives. Schmitz-Valckenberg S1, Holz FG, Bird AC, Spaide RF. Retina Mar;28(3): doi: /IAE.0b013e318164a907. Topcon Medical Systems, Inc. 111 Bauer Drive, Oakland, NJ P: