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Clinical Examination in Neuro-Ophthalmology
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Selvakumar Ambika, Krishnakumar Padmalakshmi
Optic disc edema presents as blurred elevated disc with hyperemia. Optic disc swelling may occur due to various causes (Table 1.4) and it is necessary to differentiate between true edema and pseudoedema (Table 1.5). Congenital optic disc anomalies like optic disc drusen can present as pseudoedema. Causes of pseudo disc edema are described in Table 1.6. Differentiating pseudoedema from true disc edema can avoid unnecessary investigations like neuroimaging brain and lumbar puncture. It is not necessary that all disc edemas are papilledema. It is important to differentiate an optic neuropathy from papilledema, as any disc edema with vision loss to begin with is an optic neuropathy. Papilledema patients will have normal optic nerve functions in early stages and worsen in later stages only.
Cranial Neuropathies II, III, IV, and VI
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Tanyatuth Padungkiatsagul, Heather E. Moss
Optic disc drusen are calcium deposits below the surface of the optic nerve head present in 2% of the population. There are bilateral deposits in two-thirds of cases. They cause an elevation of the optic nerve head that can be mistaken for optic nerve head edema. As patients get older and undergo some involution of the RGC axons, the calcific deposits become more visible (Figure 22.11).
One or Both Optic Discs are Swollen
Published in Amy-lee Shirodkar, Gwyn Samuel Williams, Bushra Thajudeen, Practical Emergency Ophthalmology Handbook, 2019
Optic disc drusen (ODD): Common cause of asymptomatic optic disc ‘swelling’ or pseudo-PE in children is with an incidence of 0.34%–2.4%. ODD in children are buried and calcified, which makes the initial diagnosis on the slit lamp challenging. Moreover, PE and ODD may coexist in which case other clinical signs and symptoms must be considered.
Diagnosing Optic Disc Drusen in the Modern Imaging Era: A Practical Approach
Published in Neuro-Ophthalmology, 2021
F Costello, SP Rothenbuehler, PA Sibony, S Hamann
Optic disc drusen are relevant to clinical practice for several reasons. First, ODD can masquerade as papilloedema caused by elevated intracranial pressure (ICP) (Figure 1), posing a diagnostic challenge. This is an important scenario in which a reliable, accessible means of diagnosing ODD could spare patients costly and invasive procedures aimed at excluding causes of raised ICP. Second, ODD are accompanied by visual field defects in up to 87% of adult cases.1,3 Clinicians should therefore consider this diagnosis for patients with cryptogenic perimetric abnormalities and an elevated optic nerve appearance. Finally, ODD may cause sudden-onset painless vision loss through a variety of mechanisms including non-arteritic anterior ischaemic optic neuropathy (NA-AION), central retinal artery occlusion, central retinal vein occlusion, and choroidal neovascularisation.1,3–7 In two recent retrospective studies of young individuals (aged 50 years or less) with NA-AION, 51% to 53% of NA-AION eyes harboured ODD.6,7 Hence, ODD may represent an independent risk factor for NA-AION and should be considered in the differential diagnosis, particularly for younger patients who lack known risk factors for this condition.6,7
Pathogenesis and Evaluation of the Effects of Idiopathic Intracranial Hypertension on the Optic Nerves
Published in Neuro-Ophthalmology, 2020
Nada Elsaid, Omar Ahmed, Tamer Belal, Ahmed Razek, Ahmed Azab
of the orbit is used frequently to distinguish papilloedema from pseudo-papilloedema, particularly when optic disc drusen are suspected. Pseudo-papilloedema (or pseudo-disc oedema) are the term used to describe ON variants or abnormalities that mimic papilloedema ophthalmoscopically, including congenital anomalies, tilted optic discs, hypoplastic optic discs, crowded hyperopic discs, optic disc hamartomas, myelinated nerve fibres, and optic disc drusen. Optic disc drusen is small hyaline bodies that are usually congenital, inherited, and refractile. They may be buried in the disc or visible with an ophthalmoscope by using the red-free light or shining the slit-beam at an oblique angle. Orbital ultrasound often shows a special echo resulting from calcification of the drusen.15
Neuro-Ophthalmic Literature Review
Published in Neuro-Ophthalmology, 2019
David Bellows, Noel Chan, John Chen, Hui-Chen Cheng, Peter MacIntosh, Jenny Nij Bijvank, Michael Vaphiades, Konrad Weber
Although the pathophysiology leading to nonarteritic anterior ischaemic optic neuropathy (NAION) is not yet fully understood, diabetes mellitus, hypertension, hyperlipidaemia, ischaemic heart disease, and cerebrovascular disease are established risk factors which suggest an ischaemic cause. In the present study, the authors sought to identify specific risk factors for the affection of the second eye. This is of high clinical relevance, as these are the only potentially preventable events of this vision-threatening disease. For this purpose, the authors screened 318 patients with ischaemic optic neuropathy over 10 years at their institution and identified 119 patients with NAION in their first eye. Of these 119 patients, 29 patients (24%) developed NAION in their fellow eye over a mean follow-up period of 3.6 years. In these patients, they identified the presence of bilateral optic disc drusen, especially in younger patients, as the most significant risk factor for the affection of the fellow eye with a hazard ratio of 2.8. The second significant risk factor was non-compliance to the treatment of obstructive sleep apnoea, defined as the use of continuous positive airway pressure (CPAP) masks during less than four nights per week (hazard ratio of 4.5). As a consequence of this study, patients with NAION should be asked routinely about sleep apnoea and encouraged to adhere to their CPAP treatment to prevent the potentially devastating visual effects of bilateral NAION.