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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
The differential diagnosis of monocular vision loss is large, including optic neuropathies and pathology of other ophthalmic structures. Most of the ophthalmic causes are readily appreciated on ophthalmic examination. The exception is maculopathies, damage to the central retina, which shares symptomatic features with optic neuropathies and can be occult, even on dilated fundoscopic examination. Symptom of metamorphopsia (distortion of image) or photopsia (perception of flashing lights) are unusual for optic neuropathies but suggestive of maculopathies. On the contrary, perception of dimness, pain on eye movement, and heat-induced transient visual loss (Uhthoff's phenomenon) are well described in optic neuropathies.
When There Are Symptoms But it All Looks Totally Normal
Published in Amy-lee Shirodkar, Gwyn Samuel Williams, Bushra Thajudeen, Practical Emergency Ophthalmology Handbook, 2019
Stereopsis: Assessment of stereopsis can be particularly useful when the patient describes monocular vision loss. Stereopsis requires good vision in both eyes with good binocular fusion. Therefore if the patient can demonstrate good stereopsis, they must have good visual acuity. By describing the purpose of the test as being ‘seeing how the two eyes work together’, the true intention behind the test can be masked. During binocular tests it can be difficult to work out which eye is seeing and the patient may also try to close one eye during the test. The degree of stereopsis achieved can give some indication of the true visual acuity (see Table 25.1). Your orthoptist will hopefully assist you with this test.
Treating Astigmatism
Published in John William Yee, The Neurological Treatment for Nearsightedness and Related Vision Problems, 2019
After applying the Modified Preliminary Drill, the patient also sees well in the distance and close-up equally well with his binocular vision. It overrides what he can and cannot see with his monocular vision. The difference with an anisometropic eye and a presbyopic eye as in the above example is that prior to the treatment, one of the anisometropic eye sees better than the other whereas both presbyopic eye were equally out of focus. Thus the anisometropic patient had already adapted to monovision.
Prevalence of vision conditions in children in a very remote Australian community
Published in Clinical and Experimental Optometry, 2023
Scott A Read, Shelley Hopkins, Alex A Black, Sharon A Bentley, John Scott, Joanne M Wood
The mean unaided monocular distance visual acuity was 0.01 ± 0.13 for the right eye and 0.02 ± 0.14 logMAR for the left eye (range: −0.16 to 1.34 logMAR). The mean unaided near visual acuity was similar at 0.00 ± 0.17 logMAR for the right eye and −0.01 ± 0.11 logMAR for the left eye (range −0.12 to 1.32). No children exhibited bilateral vision impairment. Four percent (n = 7) of children exhibited monocular distance vision impairment, and 4% (n = 7) exhibited monocular near vision impairment (visual acuity >0.3 logMAR). Monocular distance vision impairment that was not correctable with spectacles was evident in 3% (n = 6) of children. The causes of monocular vision impairment in these cases were either amblyopia (due to high refractive error, n = 3), or associated with past ocular trauma (n = 3).
Evaluation of Progressive Retinal Degeneration in Bipolar Disorder Patients over a Period of 5 Years
Published in Current Eye Research, 2022
Maria Satue, Juan Luis Fuentes, Elisa Vilades, Elvira Orduna, Maria Jose Vicente, Beatriz Cordon, Javier Perez-Velilla, Javier Garcia-Campayo, Elena Garcia-Martin
Visual function was tested by assessing photopic BCVA and contrast sensitivity vision (CSV). BCVA was evaluated using an ETDRS chart at two different contrast levels: 100% (High contrast VA [HCVA]) and 2.50% (Low contrast VA [LCVA]). All measurements were gathered under the monocular vision and with controlled lighting conditions and using the best correction. CSV was evaluated using the Pelli Robson chart and the CSV 1000E test. The Pelli Robson test comprises a chart with horizontal lines of capital letters organized into triplets. The contrast corresponds to a spatial frequency of 1 cycle per degree [cpd]. All patients were evaluated under monocular vision at a distance of 1 m from the chart and under controlled photopic conditions (85 cd/m2). The CSV 1000E evaluates contrast sensitivity at four different spatial frequencies (3, 6, 12, and 18 cpd). The chart comprises four rows with 17 circular patches each. The patches present a grating that decreases, in contrast, moving from left to right across the row. All patients were evaluated at the recommended distance of 2.5 m from the chart under the monocular vision.
Vision Screening in Belgian Children: Too Much or Not Enough?
Published in Ophthalmic Epidemiology, 2020
Coralie Hemptinne, Nancy La Grange, Demet Yüksel
The vision screening programs in Belgium primarily aim to detect amblyogenic risk factors in pre-school children, amblyopia in school children up to their 3rd or 4th year of primary school (i.e., up to 8 or 10 years old), and general eye health towards the end of primary school and in secondary school. Amblyopia is the most important cause of monocular vision loss in children with a prevalence of 1–5%.2 In children, amblyopia has been shown to be associated with low reading performance3 and difficulties in visuomotor skills, such as grasping or balance.4 In amblyopic adults, the lifetime risk of bilateral visual impairment (bilateral visual acuity < 6/12) is nearly doubled if amblyopia is present, compared to adults with no amblyopia. If vision loss affects the non-amblyopic eye, one in two patients are unable to continue working.5