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Published in Philip Winn, Dictionary of Biological Psychology, 2003
Condition where the far point of the eye (that is, the distance that is in focus when ACCOMMODATION is completely relaxed) is not at infinite distance. Refractive error results from a mismatch between the length of the eye, the curvature of the CORNEA and the power of the LENS. In MYOPIA (short sightedness) focusing is limited to close distances, while in HYPEROPIA (long sightedness) the far point is beyond optical infinity and an effort of accommodation is required to focus even on distant objects. In ASTIGMATISM, the cornea of the eye is not a spherical curve but is more sharply curved in one direction, so that vertical and horizontal contours are in focus at a different distances. In each case sharp vision can be restored by corrective spectacles.
Modern spectacle lens design
Published in Clinical and Experimental Optometry, 2020
As the eye rotates about its centre of rotation, the macula and the far point of the eye also rotate, the latter tracing out a spherical surface concentric with the centre of rotation of the eye upon which the far point remains. This surface is referred to as the far point sphere. The aim of spectacle lens design for distance vision lenses is to enable the lens to form point images of distant point objects on the far point sphere. In reality, the images are afflicted with various aberrations and those which are of significance to the spectacle wearer1924 are: transverse chromatic aberrationoblique astigmatismcurvature of fielddistortion.
The safety of belimumab for the treatment of systemic lupus erythematosus
Published in Expert Opinion on Drug Safety, 2019
The PLUTO study is an ongoing phase II trial of belimumab in pediatric SLE. Ninety-three pediatric patients (ages 5–17 years) were enrolled and randomized to placebo vs. belimumab 10 mg/kg, plus standard of care [54]. Results thus far point to a favorable response by belimumab in both primary and secondary endpoints, and in the overall incidence of adverse effects. One out of 53 belimumab-treated patients had a psychiatric side effect, whereas 4/40 placebo-treated patients had a psychiatric side effect. Although not clearly specified, the authors implied that depression, suicide, and self-injury were the psychiatric side effects for which they evaluated. Based on the results with belimumab in the pediatric population being very similar to the experience with belimumab in adult SLE, the FDA approved belimumab for pediatric SLE patients in 2019.
Spasm of the Near Reflex: Literature Review and Proposed Management Strategy
Published in Journal of Binocular Vision and Ocular Motility, 2018
The near reflex consists of convergence, accommodation, and pupil miosis. When looking at a near object, convergence facilitates bi-foveal fixation, accommodation keeps the image of regard in focus on the fovea, and pupil miosis increases the depth of field. Spasm of the near reflex (SNR) is an excessive response of the near reflex. Excessive accommodation pulls the far point closer, resulting in a myopic shift (pseudomyopia). This accommodative spasm (AS) may cause blurred vision. Convergence spasm (CS) can cause variable esotropia leading to binocular diplopia and, in some cases, pseudo-abduction limitation. Pupil miosis may be seen during spasms. Additional signs and symptoms reported with SNR include headache, eye pain, eye strain and general ocular discomfort, micropsia, macropsia, stomach upset, and dizziness. The signs and symptoms of SNR can vary widely. Isolated AS and CS are generally considered to be incomplete manifestations of SNR. SNR does not always manifest in its entirety and this can make detection difficult.1–4 There is no standardized protocol for treating SNR. As a result, clinicians may not have confidence devising and implementing a treatment plan if a patient presents with SNR.3,5