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Optic-disc edema will be graded based on the Frisén Scale [48] as below: Stage 0 – Normal Optic-disc Blurring of nasal, superior and inferior poles in inverse proportion to disc diameter. Radial nerve fiber layer (NFL) without NFL tortuosity. Rare obscuration of a major blood vessel, usually on the upper pole. Stage 1 – Very early optic ...
Optic disc drusen (ODD) are globules of mucoproteins and mucopolysaccharides that progressively calcify in the optic disc. [ 1 ] [ 2 ] They are thought to be the remnants of the axonal transport system of degenerated retinal ganglion cells .
Papilledema or papilloedema is optic disc swelling that is caused by increased intracranial pressure due to any cause. [1] The swelling is usually bilateral and can occur over a period of hours to weeks. [2] Unilateral presentation is extremely rare. In intracranial hypertension, the optic disc swelling most commonly occurs bilaterally.
There are many grading systems for degeneration of intervertebral discs and facet joints in the cervical and lumbar vertebrae, of which the following radiographic systems can be recommended in terms of interobserver reliability: [1] Kellgren grading of cervical disc degeneration; Kellgren grading of cervical facet joint degeneration
Unilateral or bilateral optic disc edema may occur. The exact etiology, pathogenesis and mechanism of the disc edema is unknown. [ 1 ] [ 2 ] Theories suggest that the dis edema is due to retinal vascular leakage into and surrounding the optic nerve and disruption of axoplasmic flow resulting from microvascular disease of the optic nerve head. [ 2 ]
Advanced retinopathy lesions, such as microaneurysms, blot hemorrhages and/or flame hemorrhages, ischemic changes (e.g. "cotton wool spots"), hard exudates and in severe cases swelling of the optic disc (optic disc edema), a ring of exudates around the retina called a "macular star" and visual acuity loss, typically due to macular involvement.
Since the disc is an avascular structure, it is an ideal environment for the growth of anaerobic bacteria. Propionibacterium acnes bacteria secrete propionic acid, which can dissolve fatty bone marrow and bone. Therefore, it was hypothesized that diffusion of propionic acid from the disc into the vertebrae results in bone oedema, i.e. Modic ...
Ischemic optic neuropathy (ION) is the loss of structure and function of a portion of the optic nerve due to obstruction of blood flow to the nerve (i.e. ischemia).Ischemic forms of optic neuropathy are typically classified as either anterior ischemic optic neuropathy or posterior ischemic optic neuropathy according to the part of the optic nerve that is affected.