Ophthalmology Commons^™

Altered Outer Retinal Structure, Electrophysiology And Visual Perception In Parkinson's Disease., Katie K N Tran, Pei Ying Lee, David I Finkelstein, Allison M Mckendrick, Bao N Nguyen, Bang V Bui, Christine T O Nguyen

Student and Faculty Publications

BACKGROUND: Visual biomarkers of Parkinson's disease (PD) are attractive as the retina is an outpouching of the brain. Although inner retinal neurodegeneration in PD is well-established this has overlap with other neurodegenerative diseases and thus outer retinal (photoreceptor) measures warrant further investigation.

OBJECTIVE: To examine in a cross-sectional study whether clinically implementable measures targeting outer retinal function and structure can differentiate PD from healthy ageing and whether these are sensitive to intraday levodopa (L-DOPA) dosing.

METHODS: Centre-surround perceptual contrast suppression, macular visual field sensitivity, colour discrimination, light-adapted electroretinography and optical coherence tomography (OCT) were tested in PD participants (n = …

Autosomal Dominant Optic Atrophy Plus Syndrome, Aaron W. Case Od, Lovelee E. Sayomac Od, Matthew J. Anderson Od

Optometric Clinical Practice

Background: Dominant optic atrophy (DOA) is the most commonly encountered hereditary optic neuropathy in clinical practice and is the result of a mutation in the OPA1 or OPA3 genes encoding mitochondrial membrane proteins. The resultant mitochondrial dysfunction causes a distinct set of ophthalmic findings and may progress to extra-ocular systems known as OPA plus syndrome. We present a case of late-onset OPA plus syndrome encompassing both typical ophthalmic findings and the rarer extra-ocular findings. Case Report: A 41 year-old Caucasian male presents for a second opinion regarding a previously diagnosed traumatic optic neuropathy. Examination revealed decreased best-corrected acuities, …

Effects Of Spaceflight On The Eeg Alpha Power And Functional Connectivity, Sandra Pusil, Jonathan Zegarra-Valdivia, Pablo Cuesta, Christopher Laohathai, Ana Maria Cebolla, Jens Haueisen, Patrique Fiedler, Michael Funke, Fernando Maestú, Guy Cheron

Student and Faculty Publications

Electroencephalography (EEG) can detect changes in cerebral activity during spaceflight. This study evaluates the effect of spaceflight on brain networks through analysis of the Default Mode Network (DMN)'s alpha frequency band power and functional connectivity (FC), and the persistence of these changes. Five astronauts' resting state EEGs under three conditions were analyzed (pre-flight, in-flight, and post-flight). DMN's alpha band power and FC were computed using eLORETA and phase-locking value. Eyes-opened (EO) and eyes-closed (EC) conditions were differentiated. We found a DMN alpha band power reduction during in-flight (EC: p < 0.001; EO: p < 0.05) and post-flight (EC: p < 0.001; EO: p < 0.01) when compared to pre-flight condition. FC strength decreased during in-flight (EC: p < 0.01; EO: p < 0.01) and post-flight (EC: ns; EO: p < 0.01) compared to pre-flight condition. The DMN alpha band power and FC strength reduction persisted until 20 days after landing. Spaceflight caused electrocerebral alterations that persisted after return to earth. Periodic assessment by EEG-derived DMN analysis has the potential to become a neurophysiologic marker of cerebral functional integrity during exploration missions to space.

Sakurabonsai: Protocol Design Of A Novel, Prospective Study To Explore Clinical, Imaging, And Biomarker Outcomes In Patients With Aqp4-Igg-Seropositive Neuromyelitis Optica Spectrum Disorder Receiving Open-Label Satralizumab, Jeffrey L Bennett, Kazuo Fujihara, Ho Jin Kim, Romain Marignier, Kevin C O'Connor, Robert C Sergott, Anthony Traboulsee, Heinz Wiendl, Jens Wuerfel, Scott S Zamvil, Veronica G Anania, Regine Buffels, Thomas Künzel, Annemarie N Lekkerkerker, Siân Lennon-Chrimes, Sean J Pittock

Wills Eye Hospital Papers

Background: Neuromyelitis optica spectrum disorder (NMOSD) is a rare, autoimmune disease of the central nervous system that produces acute, unpredictable relapses causing cumulative neurological disability. Satralizumab, a humanized, monoclonal recycling antibody that targets the interleukin-6 receptor, reduced NMOSD relapse risk vs. placebo in two Phase 3 trials: SAkuraSky (satralizumab ± immunosuppressive therapy; NCT02028884) and SAkuraStar (satralizumab monotherapy; NCT02073279). Satralizumab is approved to treat aquaporin-4 IgG-seropositive (AQP4-IgG+) NMOSD. SAkuraBONSAI (NCT05269667) will explore fluid and imaging biomarkers to better understand the mechanism of action of satralizumab and the neuronal and immunological changes following treatment in AQP4-IgG+ NMOSD.

Objectives: …

A Qualitative Description Of Barriers To Visual Rehabilitation Experienced By Stroke Survivors With Visual Impairment In Alberta, Canada, Kiran Pohar Manhas, Katelyn Brehon, Jennis Jiang, Karim F. Damji, Fiona Costello

Department of Ophthalmology & Visual Sciences

Background: Post-stroke visual impairment (VI) is a common but under-recognized care challenge. Common manifestations of post-stroke VI include: diplopia, homonymous hemianopia, oscillopsia secondary to nystagmus, and visual inattention or neglect. In acute care settings, post-stroke VI recognition and treatment are often sub-optimal as emphasis is placed on survival. Stroke survivors with VI often face inconsistencies when accessing care out of hospital because variable availability and subsidization of visual rehabilitation. We sought to identify gaps in care experienced by stroke survivors with VI from stroke survivors' and care providers' perspectives.
Methods: We conducted a qualitative description study across 12 care sites …

Retinal Alpha-Synuclein Accumulation Correlates With Retinal Dysfunction And Structural Thinning In The A53t Mouse Model Of Parkinson’S Disease, Katie K N Tran, Vickie H Y Wong, Anh Hoang, David I Finkelstein, Bang V Bui, Christine T O Nguyen

Student and Faculty Publications

Abnormal alpha-synuclein (α-SYN) protein deposition has long been recognized as one of the pathological hallmarks of Parkinson's disease's (PD). This study considers the potential utility of PD retinal biomarkers by investigating retinal changes in a well characterized PD model of α-SYN overexpression and how these correspond to the presence of retinal α-SYN. Transgenic A53T homozygous (HOM) mice overexpressing human α-SYN and wildtype (WT) control littermates were assessed at 4, 6, and 14  months of age (male and female,