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An Approach to Visual Loss in a Child
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Muhammad Hassaan Ali, Stacy L. Pineles
Children with mental retardation and autism represent another challenging situation for pediatric neuro-ophthalmologists since these patients may have normal visual systems despite poor visual response. Due to difficult examination of such children, the clinicians are very likely to miss occult but important ophthalmic signs and disorders in these patients. Patients with autism are increasingly reported to have congenital blindness both retinal and cortical, and vice versa. Children with autistic spectrum disorder or additional neuropsychiatric conditions like schizophrenia have disruption of magnocellular pathways in the dorsal brain which are solely responsible for motion input, and hence, these patients show delay in the development of posture and other locomotor skills (5,6).
Gonorrhea
Published in Vincenzo Berghella, Maternal-Fetal Evidence Based Guidelines, 2022
Vertical transmission to the infant can cause conjunctivitis, which if left untreated may result in blindness. Prior to routine prophylaxis of all infants at the time of birth, approximately 25% of congenital blindness in the United States was caused by gonorrheal conjunctivitis, and it remains a major cause of congenital blindness in underdeveloped countries [7, 8].
Technologies for vision impairment
Published in John Ravenscroft, The Routledge Handbook of Visual Impairment, 2019
Lauren N. Ayton, Penelope J. Allen, Carla J. Abbott, Matthew A. Petoe
On the other hand, cortical implants have increased surgical complexity, but are intended to be used by people with a much broader range of vision loss conditions. As the electrodes are implanted directly within the lateral geniculate nucleus (Vurro, Crowell and Pezaris, 2014) or the cortex (Kane et al., 2013), they do not require a retina or optic nerve to function, and hence could be a treatment option for people with conditions such as glaucoma, traumatic injury and diabetic retinopathy (Lewis et al., 2016). However, it is presumed that interpretation of prosthetic vision requires a developed visual cortex (Beyeler et al., 2017), and therefore congenital blindness has not yet been considered as a suitable indication for any implantable vision prosthesis.
The Effect of Congenital and Acquired Bilateral Anophthalmia on Brain Structure
Published in Neuro-Ophthalmology, 2021
Holly Bridge, Gaelle S. L. Coullon, Rupal Morjaria, Rebecca Trossman, Catherine E Warnaby, Brian Leatherbarrow, Russell G. Foster, Susan M. Downes
Cortical thickness in primary visual cortex (V1) has consistently been shown to be greater in congenital blindness compared with sighted controls. In the congenital anophthalmia group, regions corresponding to both V1 (t = 3.7; d.f. = 17; p < .005) and V2 (t = 3.3; d.f. = 17; p < .005) were thicker than in the sighted control group. This was not the case for any of the other regions shown in Figure 3a. Furthermore, there were no significant differences between the acquired anophthalmia group and the relevant sighted controls (Figure 3b). To aid interpretation of the null effect in the acquired group, a Bayesian t-test was also performed on these data. The Bayes factor (BF01) for the null hypothesis (i.e. no difference in cortical thickness) was 1.4 times more likely that the alternative hypothesis (a difference in cortical thickness) in V1 and 2.1 times more likely in V2. This suggests the lack of difference is not due to insufficient power.
Aplasia of the Optic Nerve: A Report of Seven Cases
Published in Neuro-Ophthalmology, 2020
Yujia Zhou, Maura E. Ryan, Marilyn B. Mets, Hawke H. Yoon, Bahram Rahmani, Sudhi P. Kurup
The variation in clinical features of ONA makes the initial diagnosis sometimes challenging. MRI is a useful diagnostic tool to detect the absence of optic nerve and optic chiasm, which ensures an accurate diagnosis of ONA. In such patients, ophthalmologists should utilize advanced MRI protocols to help better characterize the state of the visual pathway and evaluate for any additional CNS anomalies. The clinical variation of ocular and extraocular manifestations presented in the study will further our understanding of ONA and its impact on patients’ lives. Although the eye with ONA has no visual potential, affected patients may require management for other complications such as ocular hypertension, poor orbital growth, and of course the effect of blindness on other aspects of development. A multidisciplinary approach is important to address extraocular concerns and provide support for congenital blindness.
Patenting in the Public Interest: The California Institute for Regenerative Medicine Model
Published in The American Journal of Bioethics, 2018
Innovative medical therapies share this problem in a slightly different guise. In this case, patent exclusivity also enables the patent holder to charge high prices that block access. Escalating prices for prescription drugs and the very high cost of innovative medical therapies have contributed to the rise in health care costs and made many medicines unaffordable both for patients and for public insurance programs. To provide a few examples, recently developed direct acting antiviral therapies represent a major breakthrough in treating hepatitis C, the most common bloodborne infection in the United States, which affects an estimated 3 million mostly poor persons. The most commonly used antiviral drugs for hepatitis C carry a list price upward of $84,000 per person for the standard 12-week treatment course. State Medicaid programs have rationed access and chosen to cover small fractions of the infected population that would benefit from the drugs because they cannot afford to do otherwise (Chapman and Buckley 2017). The first approved gene therapy in this country to treat a form of congenital blindness costs $850,000 for a one-time treatment (Feurstien and Garde 2018). The rising cost of cancer drugs in the past 20 years has led some oncologists to believe that the prices have crossed the moral line between reasonable profits and profiteering. Oncologists warn that many cancer patients may die because they cannot afford the $20,000–$30,000 copays per year, let alone the full cost of the treatment (Kantarjian et al. 2014).