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Maxillofacial Trauma
Published in Ian Greaves, Keith Porter, Jeff Garner, Trauma Care Manual, 2021
Ian Greaves, Keith Porter, Jeff Garner
A particular clinical situation occurs when soft tissue becomes trapped in an orbital floor fracture in children. This is associated with severe pain, vomiting, white or pale sclera and the inability to look up with the affected eye. Early surgical intervention is necessary.
Pathogenesis and Immunotherapy of Cogan’s Syndrome*
Published in George S. Eisenbarth, Immunotherapy of Diabetes and Selected Autoimmune Diseases, 2019
Barton F. Haynes, Nancy B. Allen, C. Christine Cox, Rex M. McCallum, L. Michael Cobo
Episodes of vestibuloauditory dysfunction in CS are frequently indistinguishable clinically from episodes of Meniere’s disease.2,3 If hearing loss due to CS is treated within 2 weeks of onset of hearing dysfunction with prednisone, hearing acuity can be preserved in approximately 80% of patients.2,3 While most CS syndrome patients do not have life-threatening complications, approximately 10% of patients will develop a large vessel vasculitis syndrome with proximal aortitis and aortic insufficiency, or develop a more distal large vessel vasculitis with involvement of aortic arch, coronary, mesenteric, renal or iliac arteries.2 Moreover, while episodes of interstitial keratitis generally do not lead to vision loss, rarely CS patients can develop vision-threatening inflammatory ocular disease involving the retina and sclera.2
Membrane removal in proliferative vitreoretinopathy
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
Michael S L.e.e, Gary W Abrams
For a vitrectomy, we use a three-port vitrectomy system. Sclerotomy sites are usually made 3 mm posterior to the limbus through the anterior pars plana. If the PVR displaces the retina anteriorly, the sclerotomies are made closer to the limbus through the ciliary processes. Eyes with retinal detachments and PVR often have had previous surgery; therefore, the sclera should be examined for previous sclerotomies. We prefer to make new sclerotomy sites, rather than reusing previous ones. Sometimes it is necessary to make a radial sclerotomy with a microvitreoretinal (MVR) blade (Alcon, Fort Worth, TX) to prevent the extension of sclerotomy sites into previous sclerotomies. We use a 4 mm infusion port, and the tip is visualized before starting the infusion to ensure that it has penetrated the pigmented and nonpigmented epithelium of the pars plana. This is done in order to prevent subretinal or choroidal infusion.
Role of anterior segment optical coherence tomography in scleral diseases: A review
Published in Seminars in Ophthalmology, 2023
Raghav Preetam Peraka, Somasheila I Murthy
Episcleritis and scleritis are an overlapping spectrum of diseases affecting the sclera.1 These two conditions often resemble each other on a cursory examination. Differentiation between an anterior form of scleritis and episcleritis is important as episcleritis is a benign and self-limiting disease that causes superficial inflammation of the sclera as compared to scleritis which is a graver disease requiring rapid and accurate diagnosis. The treatment and prognosis of scleritis too is vastly different from episcleritis.2 Detailed history and examination are the means to help differentiate between the two. History of severe pain is a classical feature of scleritis as opposed to mild tenderness or discomfort in episcleritis. The congestion is superficial and blanches with instillation of 10% phenylephrine drops in episcleritis, however, the congestion is deeper and diffuse in scleritis. Connective tissue diseases such as rheumatoid arthritis and granulomatosis polyangiitis are known in scleritis and can help clinch the diagnosis.1,2 However, in milder cases, it is often difficult to confidently diagnose the two due to overlapping symptoms and signs.3
Development of scleral ossicles in Podocnemis expansa (Testudines: Podocnemididae) embryos exposed to atrazine
Published in Drug and Chemical Toxicology, 2021
Isabela Vieira Carneiro, Lucélia Gonçalves Vieira, Juliana dos Santos Mendonça, Líria Queiroz Luz Hirano, Sady Alexis Chavauty Valdes, Lorena Tannús Menezes-Reis, André Luiz Quagliatto Santos
The sclera, the outermost layer of the eye, is a tough structure that prevents the eyeball from changing shape in response to internal and external pressures. In some animals, scleral ossification may lead to the formation of a sclerotic ring. This structure provides support to the origin of the ciliary muscle of the lens, maintaining eyeball convexity and contributing to lens accommodation via eye shape modification, which in turn leads to changes in the distance between the cornea and fundus (Lawton 2006, Liem et al. 2012). Sclerotic rings, or scleral ossicles, are bony plates found in several vertebrate groups, including Teleosts (Franz-Odendaal 2006), Squamata (Atkins and Franz-Odendaal 2016), Testudines (Warheit et al. 1989, Franz-Odendaal 2006, Vieira et al. 2007), Galliformes (Underwood 1970) and Psittaciformes (Lima et al. 2009).
Quantitative Study of Human Scleral Melanocytes and Their Topographical Distribution
Published in Current Eye Research, 2020
Dan-Ning Hu, Shen Yao, Codrin E. Iacob, Jerome Giovinazzo, Richard B. Rosen, Hans E. Grossniklaus, Jodi Sassoon
The sclera is an opaque fibrous tissue that covers more than 4/5 of the surface of the eye. It is a densely fibrous, hypocellular tissue, and is arranged in compact collagenous bundles. The main resident cells of the sclera, the fibroblasts, are few in number and located between the fibrous bundles, with their long axis and nuclei parallel to the ocular surface and to collagen sheets.24−26 The inner surface of the sclera is covered by the lamina fusca: scleral bundles in this area are thinner and contain a large number of melanocytes which give the internal sclera a brown color.24,25 The sclera is interrupted by two large foramina, the anterior and the posterior scleral foramen. The latter is located 3 mm medial to the posterior pole and allows the exit of the optic nerve; it is funnel-shaped, has an inner diameter of 2 mm or less, and an external diameter of 3.5 mm.24−26 The sclera is also pierced by many canals which conduct the vessels and nerves entering the eye, for example the anterior ciliary vessels in the anterior part, the vortex veins posterior to the equator, and the posterior short and long arteries around the optic nerve.24−26