![]() ![]() Another limitation is the fact that the imaging technique requires training of the photographer in a new modality. The current available modalities of retinal imaging, therefore, do not replace the use of indirect ophthalmoscopy with scleral depression to evaluate the anterior retina in all quadrants. Specifically, imaging of the anterior retina superiorly and inferiorly is limited with this modality. The first limitation that is critical to recognize is the inability of wide-field imaging to image the ora serrata 360 degrees with a single image. It is important for a clinician to be aware of these drawbacks in order to appropriately analyze the volume of information that wide-field images provide. 4 Further research into the utility of wide-field imaging in pathologies such as retinal detachment, choroidal dystrophies and even macular degeneration is ongoing.Īlthough these imaging modalities are changing the way that clinicians practice medicine and have become valuable research tools, wide-field imaging currently has several limitations. For example, in the case of sickle cell retinopathy, a recent report demonstrated that wide-field imaging was able to image the peripheral retinal vascular pathology-not possible with traditional seven standard fields. Wide-field fluorescein angiography enhances this evaluation. Fluorescein angiography is able to detect vessel inflammation and incompetence that may be difficult to detect on peripheral retinal examination with an indirect ophthalmoscope. 13 In addition to diabetic retinopathy, retinal vasculitis and uveitis often present with peripheral vascular changes. 3 In addition to identifying areas of capillary non-perfusion and neovascularization, the wide-field images of diabetic patients can be instrumental in planning surgical or laser treatment. ![]() The use of wide-field angiography to image the anterior retina of patients with diabetic retinopathy, for example, has been shown to enhance the clinical evaluation (See Figure 7). Research into several retinal diseases that affect the anterior retina has been performed using wide-field imaging. ![]() These include the use of a traditional fundus camera, with peripheral sweeps to areas of interest in the periphery the Ocular Staurenghi 230 SLO Retina Lens (Ocular Instruments, Bellevue, Wash.) with the use of a scanning laser ophthalmoscope camera the Retcam (Clarity Medical Systems, Pleasanton, Calif.) and the Optos (Optos, Dunfermline, UK). There are currently four primary modalities that permit imaging of the retinal periphery in a practical manner and that are widely available. Wide-field fluorescein angiogram of the normal fundus of the right eye of a patient using the Optos. The choroidal blood vessels are accentuated.įigure 5. Wide-field image of the fundus of the right eye of a patient using the red laser of the Optos. The retinal blood vessels and the anterior retinal structures are accentuated.įigure 3. Wide-field image of the fundus of the right eye of a patient using the green laser of the Optos. Color wide-field Optos image of the right fundus of a normal patient.įigure 4. These currently provide the clinician with several options for posterior segment documentation and evaluation.įigure 2. Throughout the years, several advances have been made to posterior segment imaging. 1 This field of view was adequate for imaging of the optic nerve and the posterior pole, but provided a limited view of the retinal periphery. set a 30-degree field of view as the standard in ocular fundus photography. This camera provided a 20-degree field of view, but it wasn’t until years later that the Carl Zeiss Co. Nordensen in 1926, and this allowed for documentation of ocular fundus structures. The first reliable fundus camera was introduced by Carl Zeiss and J.W. Obtaining photographs of the posterior segment of the eye has always been challenging because illumination of the posterior segment is required simultaneously with visualization of the ocular structures by the photographer. Since the invention of the ophthalmoscope in 1851 by Hermann von Hemholtz, visualization of the posterior segment of the eye by ophthalmologists has undergone dramatic improvements. ![]()
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