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Abstract Background Intensive care medicine continues to improve, with advances in technology and care provision leading to improved patient survival. However, this has not been matched by similar advances in ICU bedspace design. Environmental factors including excessive noise, suboptimal lighting, and lack of natural lights and views can adversely impact staff wellbeing and short- and long-term patient outcomes. The personal, social, and economic costs associated with this are potentially large. The ICU of the Future project was conceived to address these issues. This is a mixed-method project, aiming to improve the ICU bedspace environment and assess impact on patient outcomes. Two innovative and adaptive ICU bedspaces capable of being individualised to patients’ personal and changing needs were co-designed and implemented. The aim of this study is to evaluate the effect of an improved ICU bedspace environment on patient outcomes and operational impact. Methods This is a prospective multi-component, mixed methods study including a randomised controlled trial. Over a 2-year study period, the two upgraded bedspaces will serve as intervention beds, while the remaining 25 bedspaces in the study ICU function as control beds. Study components encompass (1) an objective environmental assessment; (2) a qualitative investigation of the ICU environment and its impact from the perspective of patients, families, and staff; (3) sleep investigations; (4) circadian rhythm investigations; (5) delirium measurements; (6) assessment of medium-term patient outcomes; and (7) a health economic evaluation. Discussion Despite growing evidence of the negative impact the ICU environment can have on patient recovery, this is an area of critical care medicine that is understudied and commonly not considered when ICUs are being designed. This study will provide new information on how an improved ICU environment impact holistic patient recovery and outcomes, potentially influencing ICU design worldwide. Trial registration ACTRN12623000541606. Registered on May 22, 2023. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=385845&isReview=true .

Abstract Stereopsis provides critical information for the spatial visual perception of object form and motion. We used virtual reality as a tool to understand the role of global stereopsis in the visual perception of self-motion and spatial presence using virtual environments experienced through head-mounted displays (HMDs). Participants viewed radially expanding optic flow simulating different speeds of self-motion in depth, which generated the illusion of self-motion in depth (i.e., linear vection). Displays were viewed with the head either stationary (passive radial flow) or laterally swaying to the beat of a metronome (active conditions). Multisensory conflict was imposed in active conditions by presenting displays that either: (i) compensated for head movement (active compensation condition), or (ii) presented pure radial flow with no compensation during head movement (active no compensation condition). In Experiment 1, impairing stereopsis by anisometropic suppression in healthy participants generated declines in reported vection strength, spatial presence and severity of cybersickness. In Experiment 2, vection and presence ratings were compared between participants with and without clinically-defined global stereopsis. Participants without global stereopsis generated impaired vection and presence similarly to those found in Experiment 1 by subjects with induced stereopsis impairment. We find that reducing global stereopsis can have benefits of reducing cybersickness, but has adverse effects on aspects of self-motion perception in HMD VR.

Abstract Current descriptions of retinal thickness across normal age cohorts are mostly limited to global analyses, thus overlooking spatial variation across the retina and limiting spatial analyses of retinal and optic nerve disease. This retrospective cross-sectional study uses location-specific cluster analysis of 8 × 8 macular average grid-wise thicknesses to quantify topographical patterns and rates of normal, age-related changes in all individual retinal layers of 253 eyes of 253 participants across various age cohorts (n = 23–69 eyes per decade). Most retinal layers had concentric spatial cluster patterns except the retinal nerve fibre layer (RNFL) which displayed a nasal, asymmetric radial pattern. Age-related thickness decline mostly occurred after the late 4th decade, described by quadratic regression models. The ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), and outer nuclear layer + Henle’s fibre layer (ONL+HFL) were significantly associated with age (p

Purpose: We assessed a novel, public, vertical integrated care model for glaucoma management in the community. Methods: This study was a retrospective, longitudinal study of 266 patients diagnosed or suspected of glaucoma. Patients were stratified to either ongoing ophthalmology-led (n = 81) or optometry-led shared care (n = 185). Demographics and clinical characteristics, including the re-referral rate and timeliness of follow up were analysed. Results: Just under half (565/1224, 46%) of all follow up consultations over the total study period of 45 months were seen in optometry-led care, with a re-referral rate to ophthalmology of 21%. Treated patients showed a median intraocular pressure reduction of 20% and a median time delay of just two days between the actual and recommended review period. Conclusions: Shared care provides an effective option for managing the ongoing care burden in chronic stable glaucoma cases at low risk of vision loss.

BackgroundOptical coherence tomography is commonly used to measure the retinal nerve fibre layer thickness in both normal and diseased eyes; however, variation among normal eyes is common and may limit the usefulness of the results. The aim of this study was to explore the interocular asymmetries in retinal nerve fibre layer thickness in a group of normal eyes and to investigate the influence of blood vessel diameter on local retinal nerve fibre layer thickness.MethodsIn this prospective study, retinal nerve fibre layer thickness and blood vessel diameter across 100 healthy participants were measured using two optical coherence tomography instruments. Individuals were categorised into two groups based on the presence or absence of interocular retinal nerve fibre layer thickness asymmetry beyond the 75th percentile of all participants.ResultsThe superonasal sectoral retinal nerve fibre layer thickness was significantly greater in the left eye compared to the right, across all three sectors. Mean blood vessel diameter showed a corresponding difference in thickness at one of the superonasal sectors. Linear regression showed a positive and moderate correlation between blood vessel diameter and focal retinal nerve fibre layer thickness. This trend persisted across both arteries and veins, but veins showed larger variability between left and right eye in participants with marked superonasal retinal nerve fibre layer asymmetry.ConclusionRetinal nerve fibre layer thickness and blood vessel diameter vary significantly between eyes even in healthy individuals. These asymmetries in a normal population should be taken into consideration when interpreting the retinal nerve fibre layer thickness measurements from optical coherence tomography to assist in distinguishing normal variations from disease.

Optic nerve head (ONH) assessment and its interpretation in healthy patients and those with glaucoma remains a pivotal topic specifically considering rapid advancements in imaging technologies. We undertook a large-scale, mixed cohort, comparative study to assess the correlation of optic disc measurements between different imaging modalities and investigated the impact of patient and disc associated parameters.ONH sizes were obtained from one randomly selected eye of each of 209 patients using stereophotography, confocal scanning laser ophthalmoscopy and two different optical coherence tomographers (OCT). Patient related data, glaucoma status and optic disc variables, specifically oblique insertion, torsion, presence of beta PPA and spherical equivalent were recorded. Measurements between imaging modalities were analysed using Pearson correlation, linear regression analysis and Blend-Altman plots. Individual variables were compared applying multivariate regression analysis, ANOVA and chi square statistics was used to determine correlations between patient and clinical characteristics.Absolute measurements significantly differed between imaging modalities generally producing smaller measurements for OCT derived measurements of Bruch's membrane opening (BMO). Pairwise correlations between imaging modalities were between 0.83 and 0.93 for discs without myopia, oblique insertion, or beta PPA. These features impacted on measurements for individual modalities and consequently contributed to inconsistencies and variability.In comparison to planimetry, OCT derived BMO measurements are more variable in the presence of oblique insertion, beta PPA or magnification errors due to myopia. Impact of these factors, however, differs between instruments and needs to be considered to accurately interpret optic disc features in particular within the context of glaucoma diagnosis.

Mutations in the BEST1 gene constitute an underlying cause of juvenile macular dystrophies, a group of retinal disorders commonly referred to as bestrophinopathies and usually diagnosed in early childhood or adolescence. The disease primarily affects macular and paramacular regions of the eye leading to major declines in central vision later in life. Currently, there is no cure or surgical management for BEST1-associated disorders. The recently characterized human disease counterpart, canine multifocal retinopathy (cmr), recapitulates a full spectrum of clinical and molecular features observed in human bestrophinopathies and offers a valuable model system for development and testing of therapeutic strategies. In this study, the specificity, efficiency and safety of rAAV-mediated transgene expression driven by the human VMD2 promoter were assessed in wild-type canine retinae. While the subretinal delivery of rAAV2/1 vector serotype was associated with cone damage in the retina when BEST1 and GFP were co-expressed, the rAAV2/2 vector serotype carrying either GFP reporter or BEST1 transgene under control of human VMD2 promoter was safe, and enabled specific transduction of the RPE cell monolayer that was stable for up to 6 months post injection. These encouraging studies with the rAAV2/2 vector lay the groundwork for development of gene augmentation therapy for human bestrophinopathies.