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Vision and hearing
Published in Ajay Sharma, Helen Cockerill, From Birth to Five Years, 2021
The most common vision disorders among children are squint, amblyopia and optical problems impairing visual acuity. About 1 per cent of infants and 3–7 per cent of young children have a squint. At least 2 per cent of children have amblyopia, a condition of reduced vision in which the eye is healthy; still, the brain fails to develop visual function because of low vision or squint in one eye. Amblyopia is usually unilateral but rarely may be bilateral.
Endocrine Therapies
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
MPA is well absorbed orally, with blood levels peaking after 2–4 hours and a half-life of 12–17 hours. It can also be administered in a depot form (i.e., Depo-ProveraTM) by deep intramuscular injection (normally into the gluteal muscle) which provides a half-life of 40–50 days. As with most progestogens, side effects include GI disturbances (e.g., nausea), cardiovascular abnormalities (e.g., hypertension, palpitation, congestive heart failure), depression, fluid retention, breast and menstrual cycle irregularities in women, alopecia, sexual dysfunction, skin reactions, and weight changes. In addition to these general adverse effects, the glucocorticoid effects associated with MPA can lead to Cushingoid syndrome at higher doses. Also, rarely, vision disorders such as retinal thrombosis can occur, in which case treatment should be immediately discontinued. Medroxyprogesterone acetate should be avoided during conception or pregnancy, as genital malformations in the fetus may occur.
Biomedical Devices: Overview
Published in Jack Wong, Raymond K. Y. Tong, Handbook of Medical Device Regulatory Affairs in Asia, 2018
Age-related vision disorders such as cataract, muscular degeneration, and glaucoma have boosted the growth of eye-care industry in the area of cosmetic surgery such as the implantation of refractive lens. BCC Research reported that the global market for ophthalmic devices, diagnostics, and surgical equipment was valued at $15.2 billion in 2009, excluding consumer eye- care products [21]. The market is estimated to reach $19 billion by 2014. Major manufacturers include Advanced Medical Optics, Bausch & Lomb, Canon, Nidek, Topcon, and Zeiss Meditec.
Visual acuity increase in meridional amblyopia by exercises with moving gratings as compared to stationary gratings
Published in Strabismus, 2022
Uwe Kämpf, Svetlana Rychkova, Ron Lehnert, Evelyn Heim, Felix Muchamedjarow
This is relevant because, in amblyopia, the transmission quality of the focal (parvocellular) visual system, which seems to predominantly filter the frequency-modulated neuronal correlates of form perception, appears to be more impaired than that of the complementary ambient (magnocellular) system for the transmission of spectrally filtered neuronal motion correlates (cf. our discussion section of this paper for more details). Thus, at the surface, amblyopic vision disorder manifests itself as a focal dysfunction of the form channels of high spatial vs. low temporal frequency resolution.18 A comparatively less disorder appears to be observed in the function of ambient motion channels with low spatial versus high temporal frequency resolution.19 In light of this, our approach of FAVAS is designed to affect the disturbed focal (parvocellular) form-perception channels not directly but rather collaterally using the cooperative interplay with ambient (magnocellular) motion-perception channels.12–14
Early menarche in visually impaired girls: evidence and hypothesis of light-dark cycle disruption and blindness effect on puberty onset
Published in Chronobiology International, 2022
Jorge A. Barrero, Ismena Mockus
The effect of light stimulation on sexual development depends on the photic sensitivity of the individual. As a consequence, determining the extent of light perception loss becomes imperative when comparing the age at menarche in girls with different degrees of visual deficit. Since not every alteration of the visual acuity affects light perception (Schulze-Bonsel et al. 2006), the comparison of girls with NLP and girls with visual acuity lower than 20/200 or with reduced visual fields proves to be particularly useful in assessing the effect of light on sexual maturation. Most studies concluded that lower photic capability is associated with earlier menarche. However, the findings reported by Grivas et al. (2006) differ significantly, as they concluded that visually impaired women experienced delayed menarche. Among the main causes of vision disorders within their population under study, the authors reported lens abnormalities and oculomotor pathologies. In this sense, some uncertainty exists regarding these findings since it is unknown whether the lens abnormalities associated with diffraction problems and oculomotor pathologies could compromise light perception.
Relationships between certain individual characteristics and occupational accidents
Published in International Journal of Occupational Safety and Ergonomics, 2019
Mohammad Javad Jafari, Abdullah Barkhordari, Davood Eskandari, Yadollah Mehrabi
We conducted this study in 2016 on 450 frontline workers of the Arya Sasol Petrochemical Company in Bushehr, Iran, and applied a stratified random sampling technique to select the participants. Of the 450 participants, 404 (89%) completed and returned the standardized questionnaire, in which we asked the participants for personal data, including their birth date, height, weight, work experience (years in present job), education (no formal education/formal education), vocational safety training, smoking habit (non-smoker/smoker), regular intake of sedatives pills (yes, no), regular physical activities, vision disorders, hearing disorders and sleep disorders (defined as being <6 h sleep/day and/or not sleeping well and/or regular intake of sleep-inducing drugs). In the overall distribution of BMI, we defined workers with BMI between 30.0 and 39.9 (obesity categories I and II) as obese. We defined vision disorders as eye problems that may require treatment beyond prescription lenses, such as amblyopia, strabismus, color deficiency, nyctalopia and photophobia. We defined occupational injury as bodily damage resulting from work activity, whatever its consequence, which resulted from an accident at work and required sick leave of at least 1 day. To ensure an adequate number of occupational injuries, we covered a 2-year work period.