Persistent Globe Flattening in Astronauts following Long-Duration Spaceflight.

Posterior globe flattening has been well-documented in astronauts both during and after long-duration space flight (LDSF) and has been observed as early as 10 days into a mission on the International Space Station. Globe flattening (GF) is thought to be caused by the disc centred anterior forces created by elevated volume and/or pressure within the optic nerve sheath (ONS). This might be the result of increased intracranial pressure, increased intraorbital ONS pressure from compartmentalisation or a combination of these mechanisms. We report posterior GF in three astronauts that has persisted for 7 years or more following their return from LDSFs suggesting that permanent scleral remodelling may have occurred.

Radiation therapy for optic nerve sheath meningiomas: Local control and treatment related visual changes.

Objective: Our primary objective is to evaluate the local control of optic nerve sheath meningiomas (ONSMs) treated with ionizing radiation and related visual changes after treatment. Our secondary objective is to describe the clinical characteristics and perform an analysis of the treatment impact on the functional status of this group of patients. Methods: We present our series of 19 patients treated with ionizing radiation therapy at our radio-neurosurgery unit between 2016 and 2022. The setting, ophthalmological follow-up, morbidity, and survival are analyzed and discussed. Results: Patients were followed up, and the impact of treatment on local disease control, visual alterations of the affected eye, and functional status of the patient were analyzed. The progression-free survival (PFS) median was 60 months (95% CI 50.3-69.6 months). The estimated PFS rates at 48 and 66 months were 100% and 66%, respectively. At diagnosis, nine (47.3%) eyes were in amaurosis and ten (52.6%) with vision. Of the ten patients without amaurosis at the time of diagnosis, three (30%) maintained unchanged visual acuity, and seven (70%) had decreased visual acuity; three of them developed amaurosis during the first year after treatment (p = 0.018). Conclusions: Using ionizing radiation therapy is a successful treatment for the local control of ONSMs. This therapeutic modality can compromise the visual acuity of the affected eye and improve dyschromatopsia and campimetry defects. The life prognosis is good for these patients, with a zero mortality rate, but their vision prognosis is poor.

A 13-Year-Old Girl With Unilateral Visual Changes.

Neuroretinitis is a condition typically characterized by unilateral optic neuropathy and is most commonly a sequelae of cat scratch disease (CSD) due to infection with Bartonella henselae. Ophthalmologic examination will reveal a swollen optic nerve and may eventually reveal a canonical macular star; optical coherence tomography (OCT) will reveal flattening of the fovea, a thickened neurosensory retina, and subretinal fluid accumulation. Although CSD rarely presents with isolated neuorretinitis, it should be considered in patients presenting with unilateral visual changes. The differential diagnosis for neuroretinitis includes optic neuritis, inflammatory optic neuropathies (sarcoid, para-infectious, autoimmune), compressive, toxic, and more. We describe a pediatric patient presenting with visual changes that were initially concerning for optic neuritis and the diagnostic workup that ultimately led to a diagnosis of CSD neuroretinitis.

Changes to Visual Parameters Following Virtual Reality Gameplay.

Introduction: Virtual reality (VR) gameplay is popular with a range of games and educational resources available. However, it puts high demands on the visual system. Current evidence shows conflicting impacts on visual parameters. Therefore, this study explores the changes to vision following VR gameplay. Methods: The study was conducted at the School of Health Sciences, University of Liverpool. All participants had binocular vision with good visual acuity and no manifest strabismus. Participants were assessed before and after playing 15 minutes of the VR game Beat Saber, which incorporated convergence and divergence movements. Clinical assessments including near point of convergence (NPC) and near point of accommodation (NPA) using the RAF rule; accommodative convergence to accommodation (AC/A) ratio; motor fusion using the prism fusion range (at 33cm), accommodation facility using +2.00/-2.00DS flipper lenses, and stereoacuity using the Frisby stereo test were assessed before and after playing. Results: Seventy-eight participants (19-25 years old) were included in the study, with 16 males and 41 females respectively. The breakpoint of convergence reduced by 0.5 cm (p = 0.001). The binocular accommodative facility improved by 2 cycles per minute (cpm); p = 0.004. The mean, near horizontal prism fusion range (PFR) base break and recovery points both worsened by of 5.0 dioptres (p = 0.003), whereas the mean near horizontal PFR base in recovery point improved by of 4.0 dioptres (p = 0.003). Discussion: The study validated previous findings as VR gameplay over-exercised and fatigued convergence muscles, but to a small degree. The VR experience improved the participants' ability to change focus quickly and improve accommodation, as well as the divergence function of the eye. However, as the participants were retested directly after the VR gameplay, the findings were limited to short term effects on vision.

Retinal Artery Occlusion in Fibromuscular Dysplasia: A Case Report.

Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory vasculopathy with no identifiable underlying cause. Clinical manifestations of the disease typically occur at the site of occurrence. Ocular manifestations of fibromuscular dysplasia are rare but can occur in the form of central or branched retinal artery occlusions, which can cause painless monocular vision loss. We present the case of a 71-year-old female patient with FMD presenting with worsening visual acuity due to suspected right branch retinal artery occlusion. Pathology and imaging findings were consistent with classic FMD, and given our initial concerns for this patient, the rare ocular manifestations of this disease are highlighted.

Orbital metastasis of squamous cell cervical cancer: A case report and review of literature.

Common sites of metastatic disease seen in cervical cancer most often include the lungs and liver. Orbital metastasis secondary to cervical carcinoma is a rare form of metastatic disease. We report a 73-year-old woman who presented with ocular symptoms found to be secondary to orbital metastasis of cervical cancer. She underwent palliative radiation to the orbit and pelvis followed by systemic chemotherapy with carboplatin, paclitaxel, and bevacizumab. Prompt intervention was able to salvage her vision and improve her quality of life significantly. We identified 5 similar reported cases in which orbital metastasis was diagnosed simultaneously at the time of cervical cancer diagnosis. In these five cases, patients were treated with a combination of radiation and chemotherapy. Our case demonstrates an unusual presentation of isolated orbital metastatic disease secondary to squamous cell carcinoma of the cervix. Physicians should be aware that cervical cancer may metastasize to the eye leading to vision loss, and prompt intervention may be able to salvage one's vision and improve quality of life.

Review of Treatment Options for Smaller Benign Cranial Meningiomas: Observation, Stereotactic Radiosurgery, and Rarely, Open Surgery.

BACKGROUND: MR/CT documented smaller cranial meningiomas in asymptomatic patients are often followed for years without requiring any intervention. Only a subset of patients who become symptomatic attributed to significant tumor growth, edema and/or mass effect may require stereotactic radiosurgery (SRS), and rarely, open surgery. Clearly, the decision for choosing any treatment modality must be made on a case by case basis and include an analysis of risks vs. benefits to the individual patient. METHODS: Patients with smaller benign asymptomatic meningiomas are followed with sequential MR studies that typically document lack of tumor progression, edema, or mass effect. Those who become symptomatic with the typical triad (i.e. headaches, seizures, or visual loss) and other focal neurological deficits may warrant SRS, and only occasionally, open surgery. Surgery may indeed be warranted in the presence of certain mitigating factors, (e.g. young age, lesions located adjacent to by not yet invading critical structures etc.). RESULTS: This review focused largely on smaller benign asymptomatic meningiomas. The non-operative/ conservative management vs. use of SRS vs. open surgery in select cases are discussed, along with a review of the morbidity/mortality of the respective interventions. CONCLUSION: There are multiple treatment options for patients with smaller asymptomatic cranial meningiomas. SRS may be warranted for those who exhibit tumor growth, increasing edema, and/or mass effect. Only rarely is open operative intervention necessary; this must include consideration of other factors that may warrant early surgery. Notably, the 5-year survival rates for SRS ranged from 95.2% - 97%, while the 10-year survival rates varied from 88.6% - 94%.

Alexia Without Agraphia: A Rare Entity.

Pure alexia refers to an acquired disorder associated with the damage to medial occipitotemporal gyrus in the dominant hemisphere, which is also known as visual word form area (VWFA). VWFA is involved in rapid word recognition and fluent reading. Alexia without agraphia is a disconnection syndrome that occurs when the splenium is also damaged with the occipital lobe on a dominant side. We report a case of a 72-year-old right-handed male who presented with alexia without agraphia accompanied by right homonymous hemianopia resulting from acute infarct of the left occipital lobe, the splenium of the corpus callosum and posterior thalamus that probably occurred on the previous day. During the evaluation, he exhibited marked impairment in the ability to read with the vision being grossly normal. Magnetic resonant imaging (MRI) revealed an acute infarct of the left occipital lobe, the splenium of the corpus callosum and posterior thalamus. A computerized tomography angiogram (CTA) revealed left posterior cerebral artery (PCA) territory infarct without any evidence of hemorrhagic conversion. Infarction of the occipital lobe on the dominant side (left) in a right-handed individual may cause a disruption in the visual word form area and is manifested by an inability to read with no abnormalities in visual acuity.

Visual and Ocular Manifestations of Alzheimer's Disease and Their Use as Biomarkers for Diagnosis and Progression.

Alzheimer's disease (AD) is the most common form of dementia affecting the growing aging population today, with prevalence expected to rise over the next 35 years. Clinically, patients exhibit a progressive decline in cognition, memory, and social functioning due to deposition of amyloid ß (Aß) protein and intracellular hyperphosphorylated tau protein. These pathological hallmarks of AD are measured either through neuroimaging, cerebrospinal fluid analysis, or diagnosed post-mortem. Importantly, neuropathological progression occurs in the eye as well as the brain, and multiple visual changes have been noted in both human and animal models of AD. The eye offers itself as a transparent medium to cerebral pathology and has thus potentiated the development of ocular biomarkers for AD. The use of non-invasive screening, such as retinal imaging and visual testing, may enable earlier diagnosis in the clinical setting, minimizing invasive and expensive investigations. It also potentially improves disease management and quality of life for AD patients, as an earlier diagnosis allows initiation of medication and treatment. In this review, we explore the evidence surrounding ocular changes in AD and consider the biomarkers currently in development for early diagnosis.

The use of photographs to record variation in bruising response in humans.

There is considerable value in developing tools capable of accurately and reliably determining when bruises were inflicted in humans. Previous work has focused on the visual changes observed in a bruise as the injury develops and heals. However, due to variables such as how and where on the body the bruise was inflicted, differing tissue compositions at the injured skin site between individuals and inter- and intra-observer variation; a technique sufficiently robust for use in a clinical or medicolegal setting has not yet been identified. In this study we present a series of photographs taken under controlled conditions illustrating standardised bruises induced on participants using a weight dropping mechanism. We show that variation in the appearance of bruises over time across individuals is large and, although photography may be a suitable technique for the recording of injuries, it is not sufficiently reliable for determining the age of a bruise.