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Cytomegalovirus
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
Symptomatic congenital cytomegalic inclusion disease is characterized by disease of the central nervous system, including intracranial calcifications, microcephaly and ventriculomegaly, with or without ophthalmic and auditory damage [7,22]. Ill babies may have an array of clinical findings, including jaundice, hepatitis, hepatosplenomegaly, pneumonitis, petechiae, thrombocytopenia, hemolytic anemia, chorioretinitis, dental defects, and fetal growth retardation. Neurological findings include mental retardation, microcephaly, and other brain defects; abnormal eye development, including ocular atrophy and chorioretinitis; motor deficits, including paresis and paralysis; and seizures, including the infantile spasm syndrome [20]. Mortality may be as high as 30% and most survivors will suffer permanent neurodevelopmental sequelae, including retardation, behavioral problems, visual defects, and hearing loss.
The eye
Published in Angus Clarke, Alex Murray, Julian Sampson, Harper's Practical Genetic Counselling, 2019
Microphthalmos and anophthalmos constitute an extremely heterogeneous group. Unilateral cases are frequently non-genetic but cannot be securely distinguished from genetic forms. Rubella, toxoplasmosis, maternal thalidomide and other drug exposures are possible causes of bilateral disease. Mental retardation is frequently associated, and microphthalmos is a feature of several chromosomal defects as well as Mendelian syndromes. The X-linked Lenz syndrome of microphthalmos with cataract, mental retardation and digital and genitourinary abnormalities must be considered. Microphthalmos with coloboma is usually autosomal dominant (in the absence of known external causes) and is heterogeneous. Complete bilateral anophthalmia can be difficult to distinguish from extreme microphthalmos and may result from environmental factors. Cryptophthalmos, with absent palpebral fissures, may be part of the previously mentioned disorders, or may occur with relatively normal eye development, usually following autosomal recessive inheritance. Some cases are part of the more general Fraser syndrome (autosomal recessive), where renal agenesis and laryngeal atresia may be major features, and where a specific developmental gene defect is known.
An overview of human pluripotent stem cell applications for the understanding and treatment of blindness
Published in John Ravenscroft, The Routledge Handbook of Visual Impairment, 2019
Louise A. Rooney, Duncan E. Crombie, Grace E. Lidgerwood, Maciej Daniszewski, Alice Pébay
Presently, research on optic neuropathies is hampered by paucity of both readily available RGCs from living patients and in vitro RGC models. However, these issues may be addressed by use of hPSCs (Chamling, Sluch and Zack, 2016; Riazifar et al., 2014). Various protocols have been established for the generation of RGCs from stem cells (reviewed in Gill et al., 2014). Multiple groups, including ours, have focused on developing efficient and robust hPSC-derived RGC differentiation protocols (Gill et al., 2016; Huang et al., 2017; Reichman et al., 2014; Riazifar et al., 2014; Sluch et al., 2015). Differentiation protocols typically rely on modulation of several cellular signalling pathways known to be involved in embryogenesis and early eye development in order to obtain retinal progenitor cells, RGCs and then enrichment of RGCs by cell sorting (Gill et al., 2016; Sluch et al., 2015). Those RGC populations show functionality and marker profiles with close resemblance to native RGCs (Gill et al., 2016; Sluch et al., 2015). Single cell RNA sequencing analysis of RGCs differentiated and enriched by selection with the sensory neuron marker THY1 through our method has revealed three main subpopulations within the hPSC-derived RGCs (Daniszewski et al., 2018).
Outcome Measures for Disease Monitoring in Intraocular Inflammatory and Infectious Diseases (OCTOMERIA): Understanding the Choroid in Uveitis with Optical Coherence Tomography (OCT)
Published in Ocular Immunology and Inflammation, 2023
Rupesh Agrawal, Rei Chern Weng, Alex Fonollosa, Lena Giralt, Joseba Artaraz, Peizeng Yang, Fanfan Huang, Bingyao Tan, Leopold Schmetterer, Alok Sen, Vishali Gupta, Wei Xin
The choroid is a dense layer of blood vessels between the retina and the sclera, and its vasculature is vital as the primary blood supply to the outer retina. Morphologically, the choroidal vasculature can be divided into several layers, including the large vessels layer and choriocapillaris. Apart from its role as the vascular structure supplying the retina, the choroid also has several functions, such as a heat exchange mechanism for the retina via choroidal blood flow and the presence of secretory cells that is likely involved in the modulation of vascularization and growth of the sclera.1 In additional, changes in choroidal thickness have been associated with the process of accommodation of the eye, with regional changes noted in one specific study.2 It has also been linked to myopia, a common refractive error pathology, and consequently suggests an association between choroidal thickness changes and regulation of eye development, myopia development and progression.3,4
The Development of Ocular Biometric Parameters in Premature Infants without Retinopathy of Prematurity
Published in Current Eye Research, 2021
Jing Yang, Qian Wang, Conghui Li, Qiong Wu, Panpan Ma, Wei Xin
All infants underwent portable slit-lamp examination, RetCam3 (Clarity Medical Systems, California, USA), and A-scan ultrasound biometry (Topcon, Tokyo, Japan). Their growth parameters, including GA, BW and PMA were also recorded at each examination. The screening examination for ROP followed the guidelines recommended by the Royal College of Paediatrics and Child Health and the Royal College of Ophthalmologists, United Kingdom.15 Ultrasonography is widely used for clinical examinations of infants because it is safe and non-invasive.20 Ultrasonic AL measurements have been used as an indicator of eye development.21–24 The ocular biometric parameters (AL, ACD, LT and VL) were measured using A-scan ultrasound biometry. In our study, some of the participants were measured multiple times at different GA (e.g. the same subject was measured at 32 weeks and again 2 weeks later), while other participants were only measured once.
Longitudinal Analysis of Refractive Errors in Premature Children during the First Three Years of Life
Published in Journal of Binocular Vision and Ocular Motility, 2020
Lauren Hennein, Alejandra de Alba Campomanes
Amblyopia can be caused by strabismus, visual deprivation such as media opacities and ptosis, and amblyopogenic refractive errors including visually significant myopia, hyperopia, astigmatism, and anisometropia. In the United States, vision screening typically occurs between three and five years of age in an otherwise healthy child. Eye development and subsequent emmetropization may be influenced by prematurity.1–3 Even in the absence of retinopathy of prematurity (ROP), prematurity may lead to an increased risk of amblyopogenic refractive errors.4–11 Both premature children with and without ROP have been shown to be susceptible to myopia,12–15 astigmatism,1 and anisometropia9,11 compared to full-term children. Screening children for amblyopia and amblyopia risk factors (ARFs), followed by appropriate treatment, has been shown to improve visual outcomes.13 Treatment efficacy decreases as children age, and vision loss from amblyopia can be irreversible if it is not diagnosed and treated early.14