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Background: Low-contrast vision is thought to be reduced in Parkinson's disease (PD). This may have a direct impact on quality of life such as driving, using tools, finding objects, and mobility in low-light condition. Low-contrast letter acuity testing has been successful in assessing low-contrast vision in multiple sclerosis. We report the use of a new iPad application to measure low-contrast acuity in patients with PD. Objective: To evaluate low- and high-contrast letter acuity in PD patients and controls using a variable contrast acuity eye chart developed for the Apple iPad. Methods: Thirty-two PD and 71 control subjects were studied. Subjects viewed the Variable Contrast Acuity Chart on an iPad with both eyes open at two distances (40 cm and 2 m) and at high contrast (black and white visual acuity) and 2.5% low contrast. Acuity scores for the two groups were compared. Results: PD patients had significantly lower scores (indicating worse vision) for 2.5% low contrast at both distances and for high contrast at 2 m (p < 0.003) compared to controls. No significant difference was found between the two groups for high contrast at 40 cm (p = 0.12). Conclusions: Parkinson's disease patients have reduced low and high contrast acuity compared to controls. An iPad app, as used in this study, could serve as a quick screening tool to complement more formal testing of patients with PD and other neurologic disorders.

BACKGROUND:: Low-contrast visual acuity (LCVA), a sensitive measure of visual function in multiple sclerosis (MS), demonstrated treatment effects as a secondary outcome measure in the Phase 3 trial of natalizumab, AFFIRM. In these posttrial analyses, we studied the relation of visual function to quality of life (QOL), magnetic resonance imaging (MRI) measures, and Expanded Disability Status Scale (EDSS) scores. METHODS:: At baseline and at 52 and 104 weeks in AFFIRM, patients underwent binocular testing of LCVA (1.25% and 2.5% contrast) and high-contrast visual acuity (HCVA). Vision-specific QOL was assessed by the Impact of Visual Impairment Scale (IVIS), whereas the SF-36 Health Survey and Visual Analog Scale were administered as generic QOL measures and the EDSS as a measure of neurologic impairment. RESULTS:: Among QOL measures, IVIS scores showed the most significant correlations with visual dysfunction at all time points in the trial (r= -0.25 to -0.45, P < 0.0001 for LCVA and HCVA). Higher MRI T1- and T2-lesion volumes were also associated with worse vision scores at all time points (P < 0.0001). Clinically meaningful worsening (progression) of LCVA was noted in substantial proportions of patients in AFFIRM and was prevalent even among those without EDSS progression over 2 years (21.9% with LCVA progression at 2.5% contrast; 26.2% at 1.25% contrast). HCVA worsened in only 3.7% of patients without EDSS progression. CONCLUSIONS:: Loss of visual function, particularly as measured by LCVA, was common in AFFIRM, occurring in >20% of patients. Both LCVA and HCVA scores reflect vision-specific aspects of QOL, but LCVA provides information about disability progression not entirely captured by the EDSS. Vision represents a key dimension of outcome assessment for MS and adds valuable information on disability and QOL that can be useful to clinicians.This is an open access article distributed under the terms of the Creative Commons Attribution-Noncommercial-No derivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.

Clinical case reports and prospective trials have demonstrated a reproducible benefit of hypothalamic-pituitary-adrenal (HPA) axis modulation on the rate of recovery from acute inflammatory central nervous system (CNS) demyelination. As a result, corticosteroid preparations and adrenocorticotrophic hormones are the current mainstays of therapy for the treatment of acute optic neuritis (AON) and acute demyelination in multiple sclerosis. Despite facilitating the pace of recovery, HPA axis modulation and corticosteroids have failed to demonstrate long-term benefit on functional recovery. After AON, patients frequently report visual problems, motion perception difficulties and abnormal depth perception despite 'normal' (20/20) vision. In light of this disparity, the efficacy of these and other therapies for acute demyelination require re-evaluation using modern, high-precision paraclinical tools capable of monitoring tissue injury. In no arena is this more amenable than AON, where a new array of tools in retinal imaging and electrophysiology has advanced our ability to measure the anatomic and functional consequences of optic nerve injury. As a result, AON provides a unique clinical model for evaluating the treatment response of the derivative elements of acute inflammatory CNS injury: demyelination, axonal injury and neuronal degeneration. In this article, we examine current thinking on the mechanisms of immune injury in AON, discuss novel technologies for the assessment of optic nerve structure and function, and assess current and future treatment modalities. The primary aim is to develop a framework for rigorously evaluating interventions in AON and to assess their ability to preserve tissue architecture, re-establish normal physiology and restore optimal neurological function.

SUMMARY: Traumatic brain injury (TBI) is a major cause of morbidity and mortality. Concussion, a form of mild TBI, might be associated with long-term neurological symptoms. The effects of TBI and concussion are not restricted to cognition and balance. TBI can also affect multiple aspects of vision; mild TBI frequently leads to disruptions in visual functioning, while moderate or severe TBI often causes structural lesions. In patients with mild TBI, there might be abnormalities in saccades, pursuit, convergence, accommodation, and vestibulo-ocular reflex. Moderate and severe TBI might additionally lead to ocular motor palsies, optic neuropathies, and orbital pathologies. Vision-based testing is vital in the management of all forms of TBI and provides a sensitive approach for sideline or post-injury concussion screening. One sideline test, the King-Devick test, uses rapid number naming and has been tested in multiple athlete cohorts.