EasyScan brings same SLO advantages in Staurenghi Comparison
Geplaatst op 15-12-2014
Prof. Giovanni Staurenghi is Professor of Ophthalmology, Chairman Eye Clinic, Department of Clinical Science Luigi Sacco, Sacco Hospital, University of Milan. Prof. Giovanni Staurenghi, another leading proponent of SLO technology, compared the performance of the new generation compact SLO device, EasyScan, with a traditional fundus camera. “We sought to replicate a normal clinical set-up to see if it is possible to use EasyScan in a general clinical practice,” he explained. The evaluation parameters were (1) the quality of the retinal scan and (2) the number of different types of disease Staurenghi and his team could identify using each system.
Prof. Staurenghi is known for his interest in new retinal imaging technologies and techniques and admits to favouring SLO technology. “I am a little bit biased,” he said, “but the advantages of SLO are clear. The first is that you are able to identify things better because of the precision of being able to scan through a small pupil [as small as 2 mm in diameter compared to 3–4 mm for a regular fundus camera] point-by-point, without mydriasis. The second advantage of SLO is that the contrast and resolution are better and that can obviously be very useful for identifying different types of retinal pathologies, for diabetic retinopathy, for example, or a macular hole.”
For the EasyScan evaluation, Prof. Staurenghi and his team collected 70 sets and compared them on both the new SLO machine and a traditional fundus camera. The evaluation included non-mydriatic comparisons using both devices and a number of mydriatic fundus versus non-mydriatic SLO scans in more unusual or potentially complex cases. “The evaluation of the data confirmed what we expected: we see the same main advantages over fundus with the EasyScan as we do with other SLO devices,” added Prof. Staurenghi. “The core of the machine is a little bit different from other SLO machines because it is aimed at mainstream users rather than retinal specialists, and so doesn’t offer full-color SLO imaging, but it is probably the best there is outside autofluorescence imaging, and it is a really portable instrument. It does everything a clinician needs and the use of infrared light is not disturbing for the patient — not like the flash of a fundus camera. That is another big advantage. It is easy to create nice images with almost every patient, with good details and no problems.”
Is mainstream SLO the beginning of the end of the traditional fundus camera?
Geplaatst op 15-12-2014
Dr. Thomas Theelen is Associate Professor and staff ophthalmologist at the Department of Ophthalmology, Radboud University Nijmegen Medical Centre, since 2003. While eye specialists agree that Scanning Laser Ophthalmology (SLO) outperforms the traditional fundus camera, it has remained an exclusive technology until today. The physical size and high price of SLO based retinal imaging systems restricted them exclusively to hospital ophthalmology departments and large optometry practices. Now, SLO has become available for practices of all sizes, big and small, with the arrival of a compact and lightweight SLO solution. So is SLO about to go mainstream?
Among those who think it will are Dr. Thomas Theelen, Associate Professor at the Department of Ophthalmology, Radboud University Nijmegen Medical Center, the Netherlands, and Prof. Giovanni Staurenghi, of Professor of Ophthalmology at the Sacco Hospital Eye Clinic, University of Milan, Italy. They believe that today’s technological momentum will finally make SLO’s superior performance truly accessible for everyone. And, that this is essential given the rapidly growing incidence of diabetic retinopathy, AMD, and glaucoma that healthcare providers both in the West and developing countries are facing. Dr. Theelen, a firm advocate of SLO, explains why he is happy that innovations break down the barriers to SLOs widespread adoption. “Direct comparisons have already shown us that SLO images offer better contrast, and the use of multiple colored lasers allows for more precision than traditional fundus cameras.
By scanning across the posterior pole of the eye, a confocal SLO can deliver contrast-rich images with a much greater depth of field than a fundus camera, even when faced with media opacities. Especially with older patients with cataracts.” Now, today’s advances in software and hardware, he finds, “mean that SLO is not only a better imaging technique, it has also become the faster and easier retinal imaging solution.” The future is for imaging devices that are very easy to operate, can be placed in all kinds of practices, including mobile practices, and function as a standalone system as well as connect seamlessly with hospital networks.
From exclusive to commodity
“The SLO benefits are necessary to cope with the growing demand on healthcare resources. Until recently, SLO devices were not really suitable for clinical use because those older systems had very complicated software and they cost a lot.” says Dr. Theelen. “The older lasers were large and energy-hungry and the light emitted was unstable. The modern laser diodes are much cheaper, use less energy, and you can put multiple colors into a device. The EasyScan and Heidelberg devices for instance, are both small and can be used in normal practices.” EasyScan, in particular, is easy to transport and very lightweight with only 7 kg, and costs around the same as a midrange fundus camera. “At the same time, those falling component prices and increasing performance mean that the new compact SLO generation offers a lot of the performance of their bigger brethren.” Dr. Theelen says. “SLO is still evolving – we are still waiting for a real full-color SLO with red and green and, even better, white light – but even at today’s stage I can say that I have not seen any drawbacks. At Radboud, I am leading a program for the automatic detection of several retinal diseases and I would love to implement that on an SLO machine. And color SLO, which I hope to see within the next five years, will be a further major step forward.”
Since the introduction of SLO in 1979, and, especially, its confocal variant in the mid 1990s, the inherent benefits of SLO technology have helped it evolve from its early role as a platform for monochromatic imaging, fluorescein angiography and perimetry, to support new applications. Today these include confocal SLO (also known as Scanning Laser Ophthalmoscopy), Scanning Laser Doppler Flowmetry (not available), Scanning Laser Angiography, Scanning Laser Corneal Microscopy, and Scanning Laser Microperimetry.
Sensitivity and specificity
Geplaatst op 15-12-2014
By dr. Jose Martinez, Rotterdam Eye Hospital, Rotterdam, Netherlands. Staff Ophthalmologist, Rotterdam Eye Hospital, Rotterdam, The Netherlands. José Martinez Ciriano, Principal Investigator Diabetic Retinopathy Initial Validation Enrollment (DRIVE): “In DRIVE* it was shown that EasyScan’s normalized sensitivity was 100%, compared to 88.5% for the fundus camera and with similar normalized specificity. If one takes into account that for EasyScan these patients did not undergo dilation, the results are very encouraging when it comes to increasing patient care, by picking up more pathology than with a fundus camera, with at the same time a much more patient friendly procedure”.
*DRIVE: a head-to-head comparison between the SLO based EasyScan and a popular fundus camera
