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Circumpapillary Retinal Nerve Fiber Layer, Optic Nerve Head, and Related Structural Abnormalities

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Atlas of Ocular Optical Coherence Tomography

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Abstract

This chapter covers changes related to the optic disc and abnormalities in various ocular conditions. This chapter is divided into the following sections. (1) Glaucoma, the most important section of this chapter, describes different changes that can be detected in glaucoma and important considerations in the interpretation of the retinal nerve fiber layer (RNFL) thickness profile. OCT can assess glaucoma using parameters: (a) peripapillary RNFL (retinal nerve fiber layer) parameters, (b) optic nerve head parameters, (c) macular parameters. Pitfalls and artifacts in image acquisition and interpretation are fully discussed. (2) The myelinated nerve fiber layer in the optic disc area and other parts of the retina. In OCT, because the myelinated sheet of nerves can reflect light almost completely, we always have a highly reflective surface with strong shadowing of the underlying tissue. (3) The optic pit and its secondary retinoschisis. OCT in optic pit maculopathy demonstrates a combination of outer retinal layer detachment and retinoschisis in most cases. (4) Anterior ischemic optic neuropathy (AION). In early-stage AION, OCT shows a considerable increase in RNFL thickness that converts to a plateau and then atrophies in 6 months. (5) Optic disc drusen, which is a progressive disease; most cases lose the RNFL and show visual field defects in perimetry. “Lumpy-bumpy” internal reflectivity on OCT images strongly suggests drusen. (6) OCT in neurologic disease that covers new OCT findings in MS (multiple sclerosis), NMO (neuromyelitis optica), papillitis, papilledema, and intracranial lesion or tumor, and their effects on the retinal layer will completely be explained with other complementary tests and tips for differentiation between papilledema and papillitis.

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  1. Noor Ophthalmology Research Center, Noor Eye Hospital, No. 96, Esfandiar Blvd., Vali’asr Ave., Tehran, Iran

    Fedra Hajizadeh

  2. Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran

    Seyed Mehdi Tabatabaei

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  1. Fedra Hajizadeh
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    Fedra Hajizadeh

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Hajizadeh, F., Tabatabaei, S.M. (2022). Circumpapillary Retinal Nerve Fiber Layer, Optic Nerve Head, and Related Structural Abnormalities. In: Hajizadeh, F. (eds) Atlas of Ocular Optical Coherence Tomography. Springer, Cham. https://doi.org/10.1007/978-3-031-07410-3_6

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