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Severe Visual Loss (severe + visual_loss)
Selected AbstractsPerceived blur in amblyopiaOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 6 2002A. J. Simmers Purpose:, It is well documented that visual acuity and contrast sensitivity in amblyopia are attenuated at high spatial frequencies: this would predict that amblyopes should perceive objects as blurred because they lack high spatial frequency information necessary to adequately represent sharp edges. In a series of experiments, we explored the representation of blur in amblyopia with blur discrimination and blur matching tasks. Methods:, Monocular blur discrimination thresholds were measured in a spatial 2-Alternative Force Choice procedure. The luminance profiles of the blurred edge were cumulative Gaussians with the standard deviation of the reference blurred edge being fixed at 1.88, 3.75, 7.5, 15, 30, or 60 min arc. Observers were required to discriminate which edge (right or left) appeared to be the less blurred. Observers also interocularly matched edges which were identical to those employed in the blur discrimination tasks, with the exception that they were viewed dichoptically at all times. Results:, Blur discriminination thresholds were elevated in both the amblyopic and fellow fixing eye but were within the normal range for interocular matching thresholds. Our results suggest that blur is veridically represented in the amblyopic visual system. Conclusions:, The surprising result here is that all amblyopes, even those with the most severe visual loss, veridically matched all blurred edges, including the sharpest ones. This implies that amblyopes are able to represent levels of blur that are defined by spatial structure beyond their resolution limit. These results also raise interesting questions about the mechanism by which blur is represented in the visual system. [source] 1363: White dot syndromesACTA OPHTHALMOLOGICA, Issue 2010S ANDROUDI Purpose The white dot syndromes (WDS) are a group of distinct clinical entities characterized by one common underlying feature: the presence of multiple "spots" in the fundus, usually in the deep retina or choroid without any other systemic manifestations. Methods The disorders are relatively rare and include the following entities: acute posterior multifocal placoid pigment epitheliopathy (APMPPE), multiple evanescent white dot syndrome (MEWDS), birdshot retinochoroidopathy (BSRC), serpiginous choroidopathy (SC), multifocal choroiditis and panuveitis (MCP), punctate inner choroidopathy (PIC), subretinal fibrosis and uveitis syndrome, and presumed ocular histoplasmosis syndrome (POHS). Results Despite the fact that many infectious and noninfectious inflammatory diseases may present with multifocal chorioretinal lesions, the entities included in the WDS share some features which make them a particular group of ocular disorders. In fact, the WDS would be better labeled as idiopathic inflammatory multifocal chorioretinopathies, since with the exception of diffuse unilateral subacute neuroretinitis, their causes are still unknown. Conclusion Because the specific diagnosis may have profound implications on therapy and prognosis, it is important to narrow the diagnosis to the greatest extent possible, even in patients with seemingly atypical findings. The correct diagnosis of WDS is important because the management is totally different from one another. Some of them are self-limited and have good visual outcomes without treatment, while others are associated with serious retinal and choroidal sequelae, which can result in severe visual loss even after adequate immunosuppressive therapy. [source] Photodynamic therapy for chronic central serous chorioretinopathyACTA OPHTHALMOLOGICA, Issue 3 2010José M. Ruiz-Moreno Abstract. Purpose:, This study aimed to evaluate the efficacy of photodynamic therapy (PDT) in treating chronic central serous chorioretinopathy (CSC). Methods:, We describe a non-randomized, multicentre, interventional case series. A total of 82 eyes of 72 patients with chronic CSC were treated by conventional PDT. LogMAR best corrected visual acuity (BCVA) (ETDRS charts) and central foveal thickness (CFT) measured by optical coherence tomography before and after PDT, number of PDT treatments and complications were used as outcome indicators. Results:, Mean follow-up was 12 ± 10 months and mean age was 46 ± 10 years. Mean logMAR BCVA changed from 0.53 (standard deviation [SD] 0.43) before PDT to 0.38 (SD 0.41) at 3 months and 0.48 (SD 0.50) at 6 months (p < 0.0001 and p = 0.007, respectively, Student's t- test for paired data). Mean BCVA at the end of follow-up was 0.37 (SD 0.45; p < 0.0001 from baseline). Macular detachment was resolved and subretinal fluid (SRF) disappeared in all cases. Central foveal thickness decreased from 325 ,m (SD 95), to 229 ,m (SD 70) at 1 month after PDT, 206 ,m (SD 68) at 3 months, and 202 ,m (SD 76) at 6 months (all p < 0.0001, Student's t- test for paired data). No cases developed severe visual loss or complications derived from PDT. Reactive retinal pigment epithelium hypertrophy appeared in nine cases after PDT. Conclusions:, Photodynamic therapy with verteporfin may be useful in chronic CSC for improving BCVA and reducing SRF and CFT. Randomized studies with longer follow-up are needed to assess the real role of this treatment in chronic CSC. [source] Optic perineuritis as a rare initial presentation of sarcoidosisCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 7 2007Patrick Yu-Wai-Man MRCOphth Abstract Sarcoidosis is a multisystem granulomatous disorder of unknown aetiology and establishing the correct diagnosis can be challenging. Although dysfunction of the anterior visual pathways is uncommon, it is the most common neuro-ophthalmological manifestation of this condition and given the potential for irreversible, severe visual loss, prompt diagnosis and treatment are essential. We describe a patient with optic perineuritis as a rare initial presentation of sarcoidosis and discuss the underlying pathophysiology and management. [source] | ||||||||||