Laser in Clinical Ophthalmology: Possible Applications, Limitations, and Hazards

The present status of laser application in clinical ophthalmology is discussed. The differences between conventional light coagulator characteristics and those of presently available ruby lasers for clinical use are compared. The limitations and hazards of laser therapy are stressed

Fuchs\u27 spot in degenerative myopia: Clinico-pathological aspects and laser treatments

This article reviews representative literature on the epidemiology, clinical observation, pathological examination, and laser treatment of Fuchs\u27 spot in degenerative myopia. Degenerative myopia is the seventh leading cause of registered blindness in adults in · the United States. Fuchs\u27 spot is one of the major complications of degenerative myopia. With correct evaluation of the degenerative change in the macula of the myopic eye, appropriate vision care can be provided to reduce the probability of blindness. Fluorescein angiography is of great value in the detection and localization of subpigment neovascular membranes. Laser photocoagulation shows a beneficial effect on the final visual result in some cases. Fuchs\u27 spot results from two different stages in the development of a hemorrhagic disciform macular detachment in myopia. A knowledge of the exact mechanism of chorioretinal degenerations in the myopic . eye must await future research

Three-Dimensional Topographic Angiography in Chorioretinal Vascular Disease

PURPOSE. To evaluate a new angiographic technique that offers three-dimensional imaging of chorioretinal vascular diseases. METHODS. Fluorescein (FA) and indocyanine green angiography (ICGA) were performed using a confocal scanning laser ophthalmoscope. Tomographic series with 32 images per set were taken over a depth of 4 mm at an image frequency of 20 Hz. An axial analysis was performed for each x/y position to determine the fluorescence distribution along the z-axis. The location of the onset of fluorescence at a defined threshold intensity was identified and a depth profile was generated. The overall results of fluorescence topography were displayed in a gray scale-coded image and three-dimensional relief. RESULTS. Topographic angiography delineated the choriocapillary surface covering the posterior pole with exposed larger retinal vessels. Superficial masking of fluorescence by hemorrhage or absorbing fluid did not preclude detection of underlying diseases. Choroidal neovascularization (CNV) appeared as a vascular formation with distinct configuration and prominence. Chorioretinal infiltrates exhibited perfusion defects with dye pooling. Retinal pigment epithelium detachments (PEDs) demonstrated dynamic filling mechanisms. Intraretinal extravasation in retinal vascular disease was detected within a well-demarcated area with prominent retinal thickening. CONCLUSIONS. Confocal topographic angiography allows highresolution three-dimensional imaging of chorioretinal vascular and exudative diseases. Structural vascular changes (e.g., proliferation) are detected in respect to location and size. Dynamic processes (e.g., perfusion defects, extravasation, and barrier dysfunction) are clearly identified and may be quantified. Topographic angiography is a promising technique in the diagnosis, therapeutic evaluation, and pathophysiological evaluation of macular disease. (Invest Ophthalmol Vis Sci. 2001;42: 2386 -2394 C horioretinal vascular disease of the macular area (e.g., diabetic maculopathy [DMP] and age-related macular degeneration [ARMD]) are the main reasons for progressive and severe visual loss by occlusive, proliferative, and/or exudative mechanisms. 1,2 Fluorescein angiography (FA) is the classic diagnostic tool but is often compromised by masking phenomena as a consequence of the short wavelength used. Diffuse leakage of the small fluorescein molecule causes further difficulties in identifying the origin and quantifying the dynamics of leakage. Despite stereoscopic viewing systems, many lesions remain occult, and prominence and extent of exudation are evaluated only subjectively. 2,3 Indocyanine green angiography (ICGA) is effective in the near-infrared spectrum which allows improved transmission, and, mostly bound to albumin, it is thought to extravasate minimally. 5-7 Scanning laser ophthalmoscopy (SLO), with point-source illumination and optimized excitation, has further enhanced diagnostic efficacy. 9,10 The option to scan through different retinal layers is nevertheless limited to a depth resolution of approximately 300 m. It may be used, however, to obtain topographic profiles of strongly reflecting intraocular structures, such as the optic disc and the macular region. 11 Morphometric imaging of vascular structures of retina and choroid would significantly improve the diagnosis of macular disease. A novel angiographic technology, confocal topographic angiography, has been developed that allows threedimensional (3-D) documentation of vascular structures and characterization of dynamic phenomena such as perfusion and leakage. The technique of topographic image processing was applied in the FA and ICGA analyses of representative types of chorioretinal vascular disease, to document structural and dynamic changes and to evaluate the diagnostic potential of the new method. MATERIALS AND METHODS The basic topographic principle is to use a series of lateral confocal optical sections of the chorioretinal fluorescence distribution and, by introducing a smart algorithm, to extract the 3-D profile of the surface of vascular structures and related leakage. Data acquisition was achieved with a conventional confocal scanning laser angiograph. Data processing and topographic analysis were performed on a standard desktop computer, using newly developed software. The method of confocal laser scanning topography based on ICGA has been published. 12,13 Data Acquisition FA and ICGA were performed using a confocal SLO (Heidelberg Retina Angiograph; Heidelberg Engineering, Dossenheim, Germany). Infrared images were taken for optical alignment with the fovea in the center of a 30°field corresponding to a retinal area of 9 ϫ 9 mm. For FA, 5 ml of 10% fluorescein solution (Alcon Pharma GmbH, Freiburg, Germany), an argon laser emitting at 488 nm for excitation, and filters blocking transmission of wavelengths below 510 nm were used for detection. For ICGA a 50-mg solution of ICG (ICG Pulsion, München, Germany) was administered intravenously, and excitation and detection were performed, using a diode laser emitting at 795 nm and blocking filters for wavelengths below 835 nm. The diameter of the excitation beam was 10 m at the retina. The Rayleigh range of the focal beam's waist determining depth resolution was 300 m. During the early transit phase, the scanning laser was focused onto the retinal vessels and the excitation intensity was adjusted to obtain adequate illumination. An additive ϩ3-diopter (D) refractive correction was added by using the internal focus adjustment to create a preretinal initial focus for complete sectioning of elevated lesions. An early FA/ICGA series of 32 tomographic sections was taken over a depth of 4 mm, each separated From th

Multimodal imaging and diagnosis of myopic choroidal neovascularization in Caucasians

To investigate myopic choroidal neovascularization (mCNV) by fluorescein angiography (FA), spectral-domain optical coherence tomography (SD-OCT), near-infrared (NIR) reflectance, and autofluorescence (AF)

Idiopathic multifocal choroiditis/punctate inner choroidopathy with acute photoreceptor loss or dysfunction out of proportion to clinically visible lesions.

PURPOSE To report acute/subacute vision loss and paracentral scotomata in patients with idiopathic multifocal choroiditis/punctate inner choroidopathy due to large zones of acute photoreceptor attenuation surrounding the chorioretinal lesions. METHODS Multimodal imaging case series. RESULTS Six women and 2 men were included (mean age, 31.5 ± 5.8 years). Vision ranged from 20/20-1 to hand motion (mean, 20/364). Spectral domain optical coherence tomography demonstrated extensive attenuation of the external limiting membrane, ellipsoid and interdigitation zones, adjacent to the visible multifocal choroiditis/punctate inner choroidopathy lesions. The corresponding areas were hyperautofluorescent on fundus autofluorescence and were associated with corresponding visual field defects. Full-field electroretinogram (available in three cases) showed markedly decreased cone/rod response, and multifocal electroretinogram revealed reduced amplitudes and increased implicit times in two cases. Three patients received no treatment, the remaining were treated with oral corticosteroids (n = 4), oral acyclovir/valacyclovir (n = 2), intravitreal/posterior subtenon triamcinolone acetate (n = 3), and anti-vascular endothelial growth factor (n = 2). Visual recovery occurred in only three cases of whom two were treated. Varying morphological recovery was found in six cases, associated with decrease in hyperautofluorescence on fundus autofluorescence. CONCLUSION Multifocal choroiditis/punctate inner choroidopathy can present with transient or permanent central photoreceptor attenuation/loss. This presentation is likely a variant of multifocal choroiditis/punctate inner choroidopathy with chorioretinal atrophy. Associated changes are best evaluated using multimodal imaging

A Large Retinal Capillary Hemangioma in the Anterior Retina Treated with Photodynamic Therapy

www.karger.com/cop This is an Open Access article licensed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License (www.karger.com/OA-license), applicable to the online version of the article only. Distribution for non-commercial purposes only

Photoreceptor perturbation around subretinal drusenoid deposits as revealed by adaptive optics scanning laser ophthalmoscopy

PURPOSE: To describe the microscopic structure of photoreceptors impacted by subretinal drusenoid deposits, also called pseudodrusen, an extracellular lesion associated with age-related macular degeneration (AMD), using adaptive optics scanning laser ophthalmoscopy (AOSLO). DESIGN: Observational case series. METHODS: We recruited 53 patients with AMD and 10 age-similar subjects who had normal retinal health. All subjects underwent color fundus photography, infrared reflectance, red-free reflectance, autofluorescence, and spectral-domain optical coherence tomography (OCT). Subretinal drusenoid deposits were classified by a 3-stage OCT-based grading system. Lesions and surrounding photoreceptors were examined by AOSLO. RESULTS: Subretinal drusenoid deposits were found in 26 eyes of 13 patients with AMD and imaged by AOSLO and spectral-domain OCT in 18 eyes (n = 342 lesions). Spectral-domain OCT showed subretinal drusenoid deposits as highly reflective material accumulated internal to the retinal pigment epithelium. AOSLO revealed that photoreceptor reflectivity was qualitatively reduced by stage 1 subretinal drusenoid deposits and was greatly reduced by stage 2. AOSLO presented a distinct structure in stage 3, a hyporeflective annulus consisting of deflected, degenerated or absent photoreceptors. A central core with a reflectivity superficially resembling photoreceptors is formed by the lesion material itself. A hyporeflective gap in the photoreceptor ellipsoid zone on either side of this core shown in spectral-domain OCT corresponded to the hyporeflective annulus seen by AOSLO. CONCLUSIONS: AOSLO and multimodal imaging of subretinal drusenoid deposits indicate solid, space-filling lesions in the subretinal space. Associated retinal reflectivity changes are related to lesion stages and are consistent with perturbations to photoreceptors, as suggested by histology