The optic nerve, also known as cranial nerve ii, or simply as cn ii, is a paired cranial nerve that transmits visual information from the retina to the brain. This record allows the examiner to compare the present status of the patient with the baseline status without resorting to memory or grading systems. The slides are viewable in the photo gallery of my blog with the presenter. The visual fields are typically normal or may demonstrate an enlargement of the blind spot or minimal peripheral. The cranial nerve exam is a type of neurological examination. The pathophysiology of ton is unknown and probably di. Oct 23, 2009 optic nerve head examination is probably the most important step in the diagnosis of glaucoma and is also extremely important in monitoring patients with established glaucoma.
The optic nerve passes back from the posteromedial aspect of the eyeball, and through the optic canal into the middle cranial fossa. The visual fields are typically normal or may demonstrate an enlargement of the blind spot or minimal peripheral field loss, 6 rendering disease monitoring challenging. Optic neuritis on is the presence of an acute inflammation of the optic nerve that results in painful loss of vision. Nov 18, 2011 when optic disc pallor is seen, look to corroborate the finding with optic nerve dysfunction. However, on enhanced depth imagingoptical coherence tomography, bulging of the optic nerve into the globe was noted, inconsistent with an optic nerve pit. Careful examination of serial sections through the optic nerve and cyst failed to. Be certain to know which nerve is being tested next and what tests you must perform for each specific nerve. Optic perineuritis, a form of inflammation of the optic nerve sheath, typically presents with preserved central visual acuity and color vision.
Unilateral optic nerve edema with preserved visual function. Any surgical maneuver within the subarachnoid space puts the optic nerve at risk. Observations on eye examination, there were no abnormal findings in the anterior segment or ocular media. Ischemic optic neuropathy eye disorders msd manual.
Careful clinical assessment, which relies upon a thorough. The typical optical coherence tomography of an optic nerve pit shows excavation of the optic nerve with an. Optic nerve sheath decompression has been reported to be beneficial in treating optic nerve glioma, although in our patient there was no appreciable egress of csf when the optic nerve sheath was opened. Piltzseymour, clinical professor, perelman school of medicine, university of pennsylvania, usa transcript to translate please select your language to the right of this page dr piltzseymour. Visible structural alterations of the optic nerve head or retinal nerve fiber layer. Hypoglossal midbrain pons medulla anterior aspect of midbrain dorsal aspect of midbrain. The aim of this study was to quantify optic nerve involvement at time of diagnosis in a prospectively series of iih investigated at a single institution and to identify objective parameters for early diagnosis and followup. The patient must have intact cognitive abilities and the ability to cooperate in order to successfully accomplish the previously described examination tasks. Examination of the optic nerve head and retinal nerve fiber layer provides valuable structural information about glaucomatous optic nerve damage. Both optic nerves were obtained at autopsy from a 28yearold man with a 2 year history of idiopathic intracranial hypertension who had undergone bilateral optic nerve sheath decompression 14 days before death. Welcome to optic optic is an educational resource for health care professionals who are required to examine the optic nerve. Welcome to is an educational resource for health care professionals who are required to examine the optic nerve.
The ophthalmologic exam may help in showing abnormalities at the back of the eye in the optic disc, which is the part of the optic nerve visible using an instrument called an ophthalmoscope. You may be asked to only examine the visual cranial nerves cn 2,3,4,6 or the mononuclear field loss. With the indirect ophthalmoscope, cupping of the optic nerve can be detected, but, in general, optic nerve cupping and pallor appear less. Aoa, 2015 diagnosis of glaucoma is complex, but is often associated with elevated intraocular pressure, optic. When the nerve emerges from the back of the eye, it passes through the remainder of the posterior. The optic disk forms from the convergence of ganglion cell output fibres called axons as they pass out of the eye. Scars facial asymmetry neurofibromas skin lesions e. The dying back of optic nerve fibers as the child develops in utero is a natural process, and onh may be an exaggeration of that process. Beyond this level, each visual pathway receives impulses from the contralateral field of both eyes. Optic nerve disorders affecting the optic nerve are common and clinical assessment involves a history and examination. The lecture slides i used for leading a discussion on the glaucomatous optic nerve with our ubc residents on 19feb2010. It was concluded that filtration of cerebrospinal fluid after optic nerve sheath decompression may occur through an enclosed bleb of fibrosis rather than through an open fistula. Oct 31, 2005 optic nerve hypoplasia onh refers to the underdevelopment of the optic nerve during pregnancy.
For the people who have a swollen optic nerve, your doctor may consider further testing to determine if you have something other than. The optic nerve is the second of twelve paired cranial nerves cn ii. In humans, the optic nerve is derived from optic stalks during the seventh week of development and is composed of retinal ganglion cell axons and glial cells. Feb 23, 2010 the lecture slides i used for leading a discussion on the glaucomatous optic nerve with our ubc residents on 19feb2010.
Beyond this level, each visual pathway receives impulses from the contralateral field of. Photography, particularly simultaneous stereophotography, is an excellent method for recording the appearance of the optic nerve for detailed examination and sequential followup. From clinical examination of the optic disc to clinical. Up to 50% of patients with ms will develop an episode of optic neuritis, and 2030% of the time optic neuritis is the presenting sign of ms. The chapter objective is to 1 explain the anatomy of the structures related to the optic disc, retinal nerve fiber layer rnfl, optic disc, intralaminar part of the optic nerve, retrobulbar optic nerve, and the normal optic disc. These tests can guide you to the location and nature of the problem. Clinical examination of the optic nerve cybersight. This live webinar identifies the important features that define the glaucomatous optic nerve and outlines a systematic way to detect glaucoma progression on clinical examination. It is the most commonly encountered optic neuropathy in general practice,14 and is often associated with multiple sclerosis ms. The optic nerve begins at the optic disk, a structure that is 1. Sturgeweber i olfactory nerve ask patient if any problem with sense of smell use standard set of bottles of nonpungent odours ii optic nerve.
Ischemic optic neuropathy is damage of the optic nerve caused by a blockage of its blood supply. Olfaction can be tested more formally using different odours, e. There may be abnormalities of visual field testing, color vision, testing, and visual acuity testing that aid in the diagnosis. The history involves asking about a loss or decrease in vision, double vision, pain and headache and their mode of onset, progression and time course.
Clinical examination of the optic nerve springerlink. It is a diencephalic derivative that develops from the optic stalk. It is used to identify problems with the cranial nerves by physical examination. In the particular case of optic nerve sheath sonograpaphy, clinicians must integrate the patient history, physical examination, and sheath measurement to comprehend the clinical situation. Cranial nerve examination irfan ziad md ucd drkupe. It is generally accepted that the common pathway, for at least some of the toxins, is mitochondrial injury and imbalance of intracellular and. Optic nerve hypoplasia pediatric visual diagnosis fact sheet. Histopathological and ultrastructural examination of the tissue revealed fibroblasts localised to the sites of fenestration. Funduscopic examination revealed a left gray optic nerve pit and optic atrophy. The optic nerve can be swollen for many different reasons, including increased pressure on the optic nerves, loss of blood flow to the optic nerve, and inflammation inside the eye.
Optic disc the portion of the optic nerve visible within the eye. Glaucoma is a general term for a number of eye conditions that progressively damage the optic nerve, consequently causing vision loss. The medial fibres from each side cross decussate to the opposite side in the optic chiasm. However, interpretation of photographs is subjective, leading to considerable inter and intraobserver differences in classification of the optic nerve as normal or glaucomatous 18, 22, 23. Cranial nerve examination prepare patient introduction position sitting general inspection general signs. The optic nerve head is the most anterior component of the optic nerve and corresponds to the 1 mm segment that is located within the eyeball i. Optic nerve disorders range from the manifestations of lifethreatening intracranial or systemic disease, to minor congenital anomalies.
Case the patient was a 29yearold woman who had pseudoxanthoma elasticum on her neck. Full text get a printable copy pdf file of the complete article 1. Cranial nerve examination questions optic nerve ii. This will involve gross and magnified inspection of the eyeball, intricate assessment of the supporting structures of the eye, and assessment of all the cranial nerves that. You may be asked to only examine the visual cranial nerves cn 2,3,4,6 or the mononuclear field loss retinal damage or ipsilateral optic nerve lesion. The eye examination 1 stony brook university school of medicine the proper performance of a basic eye examination is a crucial skill. The indirect ophthalmoscope is used for examination of the optic disc in young children, uncooperative patients, individuals with high myopia, and individuals with substantial opacities of the media. It is the second of several pairs of cranial nerves.
Optic nerve sheath meningocele simulating an optic nerve pit. Visual acuity testing is typically performed with corrective lenses, if the patient commonly uses them, but can be performed without them. Canine optic nerve hypoplasia onh, characterized by a very small optic nerve head and blindness or severely impaired vision, is a nonprogressive congenital defect affecting one or both eyes. Be sure to perform color vision testing, pupil inspection, threshold perimetry, bestcorrected visual acuity measurement and retinal nerve fiber layer evaluation. Anatomy of optic nerve and its clinical significance. However, this is unlikely to be required in an exam. Check they can see it in the middle central scotoma optic nerve lesion.
Optic nerve sheath ultrasonography for increased intracranial. Dec 06, 2015 ubc medicine neurology clinical skills motor, sensory, and reflex examination duration. It is also called the second cranial nerve or cranial nerve ii. Mar 01, 2015 intracranial optic nerve length10mm dm4. Common cranial nerve examination questions for medical finals, osces and mrcp paces. Historically, it was thought to be a raised entity protruding from the retinal surface and by extension, was referred to as a papilla hence the term, papilloedema. Optic nervehead examination is probably the most important step in the diagnosis of glaucoma and is also extremely important in monitoring patients with established glaucoma. Sensory for smell always begin by asking patient if heshe has had any decrease in ability to smell. Ubc medicine neurology clinical skills motor, sensory, and reflex examination duration. The cranial nerve examination involves a number of steps as you are testing all 12 of the nerves in one station.
Sturgeweber i olfactory nerve ask patient if any problem with sense of smell use standard set of bottles of nonpungent odours ii. Quantitative analysis of optic nerve damage in idiopathic. Blockage can occur with inflammation of the arteries called arteritic, typically as part of a disorder called giant cell arteritis or without inflammation of the arteries called nonarteritic. We report a rare case of optic nerve drusen associated with gronbladstrandberg syndrome.
Glaucoma examinationbased studies information on data. April 29, 2020 in the real world, the clinician will be expected to examine the entire eye. Optic nerve assessment and evaluation can be a complex task, but it is hoped that this website helps by way of a comprehensive image library and a series of useful tutorials. Histopathological and ultrastructural examination of optic. A case of optic nerve drusen associated with gronblad. Capturing an image of the optic disc with a fundus camera yields a simple, relatively lowcost, and objective record of the appearance.
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