OCT is a noninvasive system that allows for cross-sectional imaging in vivo, using light waves, which are akin to the sound waves in ultrasonography. The purpose of this article is to discuss the interpretations and limitations of OCT imaging. Hydroxychloroquine sarcoidosis dosage Define hydroxychloroquine Figure 2a and 2b this classic representation of Plaquenil toxicity is a preservation of the outer retinal layers subfoveally with perifoveal loss of the IS/OS junction on both sides of the fovea. Perifoveal IS/OS junction loss is associated with perifoveal outer retinal thinning, resulting in an ovoid appearance in the central retina, creating the flying saucer sign. Eyes with obvious toxicity had greater inferior outer ring thinning 12 months after drug cessation compared to early toxicity p = 0.002, 95 % CI −2 to −8 μm. In obvious toxicity, the nasal inner subfield showed more thinning than the temporal inner subfield at 12 months after drug cessation p = 0.018, 95 % CI −1 to −8 μm. The exact mechanism of retinal toxicity is still under investigation. Despite the evident clinical changes in retinal pigmented epithelium RPE when the maculopathy is already visible, studies in animals after long exposure to chloroquine demonstrated that the first site of damage is most probably the ganglion cell layer.” Low-coherence interferometry was then adapted for use in OCT. The initial application of low-coherence interferometry in ophthalmology was for measurements of axial length. Ganglion cell layer and plaquenil toxicity Chloroquine and Hydroxychloroquine Toxicity Treatment., Expanded spectral domain-OCT findings in the early. Half life of hydroxychloroquine sulfate Plaquenil-induced maculopathy is a form of retinal toxicity that is associated with long-term use of of the anti-inflammatory medication plaquenil. The drug-induced maculopathy is associated with the following risk factors Cumulative dose level of 1,000 grams of plaquenil. Patients with existing retinal or macular disease. Plaquenil-Induced Toxic Maculopathy - Decision-Maker PLUS. COPE Disclosures Plaquenil Toxicity Update. A New Objective Parameter in Hydroxychloroquine-Induced.. Previous histopathological studies reported that the initial dramatic changes of hydroxychloroquine toxicity were observed in the retinal ganglion cell layer 18, 19. On the other hand, recent OCT studies have suggested that selective thinning of perifoveal inner plexiform and ganglion cell layers was found in patients treated with long-term hydroxychloroquine. Medications like plaquenil and chloroquine can induce degenerative changes in the ganglion cells and photoreceptor cells of the retina. DEFINITION Toxic maculopathy is a form of retinal toxicity that is associated with antimalarial agents such as plaquenil and chloroquine. Thinning of the GCL and a decrease in visual functions should theoretically occur in concurrence with or follow degenerative loss of ganglion cells. The degree of ganglion cell degeneration that is sufficient to produce clinical symptoms or a detectable abnormality on psychophysical testing is essentially unknown.