Acute visual loss
Sherif Gonem, Ian Pavord in Diagnosis in Acute Medicine, 2017
Visual loss may be caused by pathology affecting any part of the neurological pathway comprising the eye, optic nerve, optic chiasm, optic tract, optic radiation and occipital cortex. Disruption of this pathway may result in visual field defects, reduced visual acuity or complete visual loss. The commonest ocular causes of acute visual loss are acute angle-closure glaucoma (AACG), retinal vascular occlusion, retinal detachment, and preretinal or vitreous haemorrhage. The optic nerve is commonly affected by ischaemia, demyelination and drug toxicity. The optic chiasm lies adjacent to the pituitary gland, and thus pituitary and suprasellar tumours often result in bitemporal hemianopia, due to impingement on the central fibres that are crossing over at this site. The optic tract, optic radiation and occipital cortex are vulnerable to any of the pathologies that may affect the cerebral hemispheres in general, including ischaemia, haemorrhage, neoplasia and demyelination.
Clinical Examination in Neuro-Ophthalmology
Vivek Lal in A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Patients with complaints of visual field defects, headache, neurological deficits and in unexplained vision loss, testing of visual fields will be helpful. Visual field examination is accomplished by two methods—static and kinetic. In static perimetry, the stimulus is held constant, while the intensity is varied to determine the threshold intensity values. Here, there is very little role for the operator. Examples include Humphrey, Octopus and Goldmann perimetry. In kinetic perimetry, the intensity and size of the stimulus remain constant and the stimulus is moved from the non-seeing area to the seeing area and depends on the experience of the operator. Examples include Goldmann perimetry and Tangent screen.
Neuroendocrine disease
Philip E. Harris, Pierre-Marc G. Bouloux in Endocrinology in Clinical Practice, 2014
Unlike other types of pituitary tumors, most NFPAs and gonadotrophinomas present with pressure symptoms, hypopituitarism, or both, rather than with clinical syndromes related to hormone hypersecretion. Impaired visual acuity and visual field defects are common presenting symptoms.40 Occasionally, they may be associated with clinical evidence of gonadotrophin hypersecretion.55 Macroadenomas are frequently associated with hyperprolactinemia due to stalk compression.56 Consequently, they may be mistaken for prolactinomas and vice versa. Any patient presenting as an emergency with visual disturbance must have serum prolactin measured as a matter of urgency.
Polymorphism rs7961953 in TMTC2 gene is not associated with primary open-angle glaucoma in a Saudi cohort
Published in Ophthalmic Genetics, 2019
Altaf A. Kondkar, Taif A. Azad, Faisal A. Almobarak, Khaled K. Abu-Amero, Saleh A. Al-Obeidan
The study adhered to the tenets of the Declaration of Helsinki for human research. Clinically diagnosed POAG patients and glaucoma-free healthy controls of Saudi origin were selected from the anterior segment and general ophthalmology clinic at King Abdulaziz University Hospital, Riyadh, Saudi Arabia. Genotyping for polymorphism rs7961953 was done using the TaqMan® SNP Genotyping Assay (Assay ID: C_12124303_10; Applied Biosystems Inc., Foster City, CA, USA) on ABI 7500 Real-Time PCR System (Applied Biosystems Inc.). The details of selection criteria and genotyping have been described elsewhere (5). Briefly, POAG patients satisfied the following clinical criteria that included the presence of (i) the optic disk or retinal nerve fiber layer defect; (ii) visual field defects; (iii) bilateral open anterior chamber angles; and (iv) adult onset. Secondary cases of pigmentary glaucoma, uveitic, pseudoexfoliation, and patients with history of steroid use or ocular trauma were excluded. The control subjects were > 20 years of age at recruitment; normal IOP (< 21 mmHg); open angles with normal optic disk on examination; and no history of ocular disease(s) or previous ophthalmic surgeries. Subjects refusing to participate in the study were excluded. Statistical analyses was performed using SPSS version 22 (IBM Inc. Armonk, NYis, USA) and a p value <0.05 was considered statistically significant.
The Treatment of Acute Optic Neuritis
Published in Seminars in Ophthalmology, 2023
Kiandokht Keyhanian, Bart K. Chwalisz
The ONTT presented the largest longitudinal ON cohort to date, and the results from the ONTT continue to inform the treatment of typical ON. In the ONTT, 95% of patients had visual acuity of at least 20/40 and 70% of patients had visual acuity of 20/20 after one year.15 More profound visual field defects at presentation appear to be associated with a higher likelihood of significant and persistent visual field defects. Nevertheless, even in mild cases of typical optic neuritis and with some spontaneous improvement, visual outcome is not guaranteed to return to patient’s baseline.16,17 Also, regaining visual acuity does not necessarily equate to functional visual recovery, as patients often have persistent visual field defects and deficient contrast sensitivity and color saturation.17
Optic Nerve Head Drusen: An Update
Published in Neuro-Ophthalmology, 2018
Edward Palmer, Jesse Gale, Jonathan G. Crowston, Anthony P. Wells
Visual field defects are much more common than visual symptoms. In children there are challenges in visual field testing, but 14–51% of children with ONHD have defects on automated testing.29,66 Field defects are more severe with visible ONHD and those with thinning of the peripapillary RNFL on OCT imaging.29 Among adults, up to 87% have visual field abnormalities depending on selection criteria and field testing sensitivity, and those with visible drusen have more field defects.4,5,24,71 Arcuate field defects, enlarged blind spots, nasal steps, and constricted visual fields are the most common abnormalities at any age, indicating the damage to axons occurs in the optic nerve head.29 In patients with buried ONHD, a smaller minority (5–25%) have visual field defects, rarely an inferior arcuate defect but more often enlargement of blind spot or peripheral constriction of the field.4,72,73
Related Knowledge Centers
- Field of View
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