Additionally, Alzheimer`s patients are reported to have three times larger cup-to-disc ratios when compared to controls without the disease. The difference was present in the upper and lower quadrant, but not in the nasal and temporal quadrant. Lu et al used OCT and found that patients suffering from Alzheimer's disease have significant RNFL thinning compared to healthy individuals at the same age. OCT in Alzheimer's and Parkinson`s disease Furthermore, we can observe different damage pattern in different MS forms. Peripapillary RNFL thickness correlates with best corrected visual acuity and is also related to contrast sensitivity, color vision, EDSS (expanded disability status scale) and brain atrophy. Approximately 6 months after the acute attack of neuritis it is possible to detect peripapillary RNFL thinning. In the acute period of retrobulbar optic neuritis we can see either normal, diminished or increased RNFL thickness, the latter being due to subclinical axonal edema. Post mortem studies have shown that 99% of MS patients have demyelinisation loci on the optic nerves. This is seen also in those MS patients, who have never had any ocular complaints. According to several studies the peripapillary RNFL thickness in MS patients is diminished. MS can affect sight in several ways causing uveitis, optic neuritis, chronic optic neuropathy, retrochiasmatic visual field defects, double vision, nystagmus and affect information processing in the brain cortex. The use of OCT in examining people with multiple sclerosis (MS) and demyelinating optic neuritis is thoroughly researched and has become an essential biomarker in the progression the disease and response to therapeutic regimens in MS patients and other neurological disorders OCT in multiple sclerosis and demyelinating optic neuritis Since a significant portion of retinal ganglion cell bodies reside in the macula, a loss of tissue there helps to identify optic nerve damage. With the development of OCT technology and high resolution devices it is now possible to measure also macular ganglion cell layer thickness. Īs we can evaluate both average RNFL thickness and its thickness in different sectors, we have a valuable tool for evaluating the correlation between clinical findings and morphological parameters (atrophy of inferotemporal RNFL sector results in upper temporal field arcuate defect). We see RNFL thinning in neurodegenerative diseases, toxic and nutritional neuropathies, in inflammatory and ischemic processes after acute period has subsided. The reason for RNFL thinning is loss of ganglion cell axons, a process which eventually leads to the optic atrophy. Thickening of the RNFL is caused by the axonal edema and is generally present in acute processes: optic neuritis, acute ischemia and short term intracranial hypertension. The RNFL is made up of retinal ganglion cell axons. The most valuable structural parameter when examining patients with neurologic diseases is peripapillary retinal nerve fiber layer (RNFL) thickness. The most useful OCT parameters in the management of neuro-ophthalmologic conditions 4 OCT in differential diagnosis of papilledema and pseudopapilledema.3 OCT in Alzheimer's and Parkinson`s disease.2 OCT in multiple sclerosis and demyelinating optic neuritis.1 The most useful OCT parameters in the management of neuro-ophthalmologic conditions.
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