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Approach to “Visual Loss”
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Aastha Takkar Kapila, Monika Singla, Vivek Lal
Ischemic optic neuropathies (anterior/posterior) ischemic optic neuropathy can be anterior or posterior and often presents with sudden-onset visual deficit, often maximum at onset. Anterior ischemic optic neuropathy (AION) involves ischemic damage to the optic nerve head. It can be non-arteritic (non-arteritic anterior ischemic optic neuropathy [NAION]) or arteritic (A-AION), the latter being associated with giant cell arteritis. While NAION is the most common form of non-glaucomatous optic neuropathy in elderly individuals, arteritic AION is associated with vasculitis and is the most common ophthalmic manifestation of giant cell arteritis (GCA). It is a treatable neuro-ophthalmic emergency, which is exceedingly important to recognize and differentiate from more common NAION. The patients of AION usually have unilateral disc edema (pale disc edema with hemorrhages) and show a “classical” altitudinal horizontal field defect on visual field testing (because of the peculiar blood supply of the optic disc).8,9
Diabetic Neuropathy
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
Ischemic optic neuropathy occurs when blood does not flow normally to the optic nerves, causing long-term damage. Vision is lost in one or both eyes. This disease can affect central or peripheral vision – or both. Vision loss is usually permanent, though many affected individuals still retain some amount of peripheral vision. Diabetes is one of the common causes of ischemic optic neuropathy. There are two general subtypes of this disease: Arteritic and nonarteritic. The arteritic form is caused by temporal arteritis, also known as giant cell arteritis. The more common nonarteritic form is caused by cardiovascular risk factors that include diabetes mellitus, hypertension, and high cholesterol. It usually occurs in slightly younger patients and is less likely to cause total loss of central vision. The arteritic form usually involves complete or nearly complete vision loss.
Clinical Applications of IVIM MRI to the Nervous System
Published in Denis Le Bihan, Mami Iima, Christian Federau, Eric E. Sigmund, Intravoxel Incoherent Motion (IVIM) MRI, 2018
Anterior ischemic optic neuropathy refers to a specific infarction of the optic nerve at the level of the optic disc, resulting in sudden, painless vision loss. In clinical practice, conventional MRI provides little information on the microcirculation disorders underlying this disease, probably because of the small region involved in a distal perfusion region. This might not be a problem for IVIM perfusion imaging because of the local nature of the method. Indeed, in an impressive study, Lu et al. [16] found a significant reduction in the IVIM perfusion fraction in the optic disc affected by anterior ischemic optic neuropathy compared to the nonaffected contralateral side, as well as compared to normal control. They suggest that IVIM could be helpful for the diagnosis as well as for the assessment of the treatment efficacy or prognosis of this disease.
Glaucoma Mimickers: A major review of causes, diagnostic evaluation, and recommendations
Published in Seminars in Ophthalmology, 2021
Sirisha Senthil, Mamata Nakka, Virender Sachdeva, Shaveta Goyal, Nibedita Sahoo, Nikhil Choudhari
e) Ischemic optic neuropathy: Ischemic optic neuropathy is frequently associated with superior or inferior altitudinal field defects. The defects affecting the Hemi-half show deep and absolute scotomas in most test points unlike in glaucoma which is characterized by relative scotoma and possible presence of a gradient (Figure 19). Further, glaucomatous defects typically start from the nasal area and progress towards the temporal side and the blind spot. In other words, glaucomatous defects evolve over a period from incomplete to complete defects. In ischemic optic neuropathy, the field defect occurs in a short time due to an acute event and does not progress over time. The field defects are generally inferior and nasal (corresponding to the superior temporal optic nerve head area, which is a watershed zone and is extremely vulnerable to ischemic damage).62
Anti-Neutrophil Cytoplasmic Antibody-Associated Ocular Manifestations in Japan: A Review of 18 Patients
Published in Ocular Immunology and Inflammation, 2021
Masaru Miyanaga, Hiroshi Takase, Kyoko Ohno-Matsui
Among the 18 patients positive for serum ANCAs, optic nerve involvement was observed in 9 patients (50%) and was the most common ocular manifestation reported in this study population. Other ocular manifestations included scleritis in 5 patients (28%; Figure 1), iritis in 5 patients (28%), retinal vasculitis in 3 patients (17%; Figure 2), oculomotor disorder in 3 patients (17%), and peripheral ulcerative keratitis in 2 patients (11%; Figure 3). Eight patients had multiple ocular manifestations. In the 9 patients with optic nerve involvement, optic papillitis (Figure 4), the most common finding, was reported in 5 patients, followed by retrobulbar optic neuritis in 3 patients. Ischemic optic neuropathy was reported in only 1 patient. Oculomotor disorders included 1 case each of lateral rectus and inferior rectus muscle swelling and 1 case of abducens nerve palsy.
Optical Coherence Tomography-Based Scattering Properties of Retinal Vessels in Glaucoma Patients
Published in Current Eye Research, 2018
Robert Kromer, Sebastian Boelefahr, Brendan Eck, Shafin Rahman, Maren Klemm
The medical history and records of all participants were reviewed for diseases that could possibly affect the retinal nerve fiber layer (RNFL). Only participants satisfying inclusion and exclusion criteria were included. The ophthalmic inclusion criteria for all patients were that they needed to have (i) best-corrected visual acuity of 0.3 LogMAR or better, (ii) spherical equivalent within ± 5.0 diopters, and (iii) normal results for visual field testing. The exclusion criteria were (i) intense alcohol abuse, (ii) body mass index > 30 kg/m2, (iii) anterior ischemic optic neuropathy, (iv) congenital abnormalities of the optic nerve, (v) untreated cardiovascular diseases, and (vi) post status cardiovascular events (e.g. myocardial infarctions). Inclusion and exclusion criteria for patients with OAG were the same, with the exception of the normal visual field testing results.