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Refractive Errors, Myopia, and Presbyopia
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Ka Wai Kam, Chi Pui Pang, Jason C. S. Yam
Hyperopia (or hypermetropia) refers to the condition where lights are focused behind the retina. Thus distant objects can be seen more easily but light rays emerging from near objects cannot be converged sufficiently on to the retina. People with hyperopia therefore often complain about difficulties with near visual tasks and require additional converging lenses as a refractive correction. Hyperopia, defined as a SER of ≥+2.0 D, is common during infancy and childhood. While neonates are born with hyperopia, from 3 months of age onwards, most infants display a progressive change in mean refraction from +2.0 D to approximately +0.75 D, a process of emmetropization. Some high hyperopes may fail to emmetropize and slowly evolve towards low hyperopia. In particular, moderate to high hyperopia (≥+4.0 D) is known to reduce visual function, including visual acuity, stereoacuity, and accommodative response,144 and increase the risk of esotropia.145,146
Retinal Vein Thrombosis
Published in K. Gupta, P. Carmichael, A. Zumla, 100 Short Cases for the MRCP, 2020
K. Gupta, P. Carmichael, A. Zumla
There are several conditions which predispose to retinal vein thrombosis: Hyperviscosity syndrome (myeloproliferative disorders, myeloma).Hypertension.Diabetes mellitus.Glaucoma and hypermetropia.
Neurology and neurosurgery
Published in Jagdish M. Gupta, John Beveridge, MCQs in Paediatrics, 2020
Jagdish M. Gupta, John Beveridge
12.16. Convergent squintis less common than divergent squint in children.is often associated with hypermetropia.may be completely reversed by the use of spectacles.often resolves spontaneously at the age of about 5 years.is clinically significant principally because of its cosmetic effects.
Corneal aberrations andanisometropia in children
Published in Clinical and Experimental Optometry, 2022
Xiaoxiao Sun, Yu Zhang, Yueguo Chen
In this study, the higher myopic eyes of children with high anisometropia had lower coma than in the contralateral lower myopic eyes in total cornea and anterior corneal surface with 3 mm diameter. However, no statistically significant interocular differences in corneal HOAs were found in children with low anisometropia. Llorente et al.18 found that patients with hypermetropia tend to have higher corneal spherical aberration than that observed in myopia. Anbaret et al.10 reported that patients with hypermetropia presented with the highest corneal coma and the lowest corneal spherical aberration as compared to patients with mild-to-moderate myopia and high myopia. In this study, 14 children in high anisometropia group had unilateral myopia; therefore, refraction types may be a possible cause of statistically significant interocular differences in corneal coma observed in the current study.
Strabismus controversies that inspired the foundation of the Donders Society for Strabology and of the journal Strabismus
Published in Strabismus, 2022
In the ELISSS, 13.5% of children operated around 20 months vs. 3.9% (P < .001) of those operated around 49 months had gross stereopsis (Titmus Housefly) at age 6; there was no difference in stereopsis beyond Titmus Housefly.15 The reoperation rate was 28.7% in children operated early vs. 24.6% in those operated late. Unexpectedly, 8.2% of the children scheduled for early surgery at an average age of 11 months and 20.1% of the children scheduled for late surgery at an average age of 11 months, had not been operated at the age of 6 years. Most of these had regressed into a microstrabismus. Esotropia less than 14° at baseline at approximately 11 months of age had not been operated at the age of 6 years in 35% of the cases. Hypermetropia of + 4 diopters or more much increased the likelihood of regression into a microstrabismus without surgery, underscoring the need of full refractive correction. A meta-regression analysis of the ELISSS and 12 other studies16 showed that reoperation rates were 60–80% for children first operated around age 1 and 25% for children operated around age 4.
A Novel AIPL1 Nonsense Mutation: Case Report of Three Siblings Diagnosed with Leber Congenital Amaurosis
Published in Fetal and Pediatric Pathology, 2020
Postnatal early onset symptoms, nystagmus, amaurotic pupils, vasculopathy, strabismus, vision loss, oculodigital sign, retinal coloboma retinal pigment epithelium atrophy and loss of outer retinal structures on OCT, macular atrophy and dystrophic retina on fundal examination and lens preservation are the general features of the disease as in our patients. It has been reported in the literature that glaucoma may sometimes be observed in these patients, but such a finding was not found in our patients during palpation examination. The most common (66%) refractive error is moderate hypermetropia. Keratoconus and cataract are observed in one of about 3 patients [4]. Hypermetropia was observed in two of our patients. In addition, we observed cortical cataract and keratoconus associated high myopia in one of our patients. We think that the cause of the cortical type of cataract is related to stage 4 (hydrops) keratoconus. AIPL1 and CRB1 mutations are more related to cataract and keratoconus [5]. Although retinal dots are frequently reported in the literature associated with LCA types 5, 7, 10 and 11; black retinal dots were also observed in our patient S2 [6–8].