Lesions Causing Alice in Wonderland Syndrome Map to a Common Brain Network Linking Body and Size Perception.

OBJECTIVE: Alice in Wonderland syndrome (AIWS) profoundly affects human perception of size and scale, particularly regarding one's own body and the environment. Its neuroanatomical basis has remained elusive, partly because brain lesions causing AIWS can occur in different brain regions. Here, we aimed to determine if brain lesions causing AIWS map to a distributed brain network. METHODS: A retrospective case-control study analyzing 37 cases of lesion-induced AIWS identified through systematic literature review was conducted. Using resting-state functional connectome data from 1,000 healthy individuals, the whole-brain connections of each lesion were estimated and contrasted with those from a control dataset comprising 1,073 lesions associated with 25 other neuropsychiatric syndromes. Additionally, connectivity findings from lesion-induced AIWS cases were compared with functional neuroimaging results from 5 non-lesional AIWS cases. RESULTS: AIWS-associated lesions were located in various brain regions with minimal overlap (≤33%). However, the majority of lesions (≥85%) demonstrated shared connectivity to the right extrastriate body area, known to be selectively activated by viewing body part images, and the inferior parietal cortex, involved in size and scale judgements. This pattern was uniquely characteristic of AIWS when compared with other neuropsychiatric disorders (family-wise error-corrected p < 0.05) and consistent with functional neuroimaging observations in AIWS due to nonlesional causes (median correlation r = 0.56, interquartile range 0.24). INTERPRETATION: AIWS-related perceptual distortions map to one common brain network, encompassing regions critical for body representation and size-scale processing. These findings lend insight into the neuroanatomical localization of higher-order perceptual functions, and may inform future therapeutic strategies for perceptual disorders. ANN NEUROL 2024.

Efficacy and safety of avacincaptad pegol in patients with geographic atrophy (GATHER2): 12-month results from a randomised, double-masked, phase 3 trial.

BACKGROUND: Geographic atrophy is an advanced form of dry age-related macular degeneration that can lead to irreversible vision loss and high burden of disease. We aimed to assess efficacy and safety of avacincaptad pegol 2 mg in reducing geographic atrophy lesion growth. METHODS: GATHER2 is a randomised, double-masked, sham-controlled, 24-month, phase 3 trial across 205 retina clinics, research hospitals, and academic institutions globally. To be eligible, patients had to be aged 50 years or older with non-centrepoint-involving geographic atrophy and best corrected visual acuity between 20/25 and 20/320 in the study eye. Eligible patients were randomly assigned (1:1) to monthly avacincaptad pegol 2 mg administered as a 100 µL intravitreal injection or sham for the first 12 months. Randomisation was performed using an interactive response technology system with stratification by factors known to be of prognostic importance in age-related macular degeneration. Patients, investigators, study centre staff, sponsor personnel, and data analysts were masked to treatment allocation. The primary endpoint was geographic atrophy lesion size measured by fundus autofluorescence at baseline, month 6, and month 12. Efficacy and safety analyses were done in the modified intention-to-treat and safety populations, respectively. This trial is registered with ClinicalTrials.gov, NCT04435366. FINDINGS: Between June 22, 2020, and July 23, 2021, 1422 patients were screened for eligibility, of whom 448 were enrolled and randomly assigned to avacincaptad pegol 2 mg (n=225) or sham (n=223). One patient in the sham group did not receive study treatment and was excluded from analyses. There were 154 (68%) female patients and 71 (32%) male patients in the avacincaptad pegol 2 mg group, and 156 (70%) female patients and 66 (30%) male patients in the sham group. From baseline to month 12, the mean rate of square-root-transformed geographic atrophy area growth was 0·336 mm/year (SE 0·032) with avacincaptad pegol 2 mg and 0·392 mm/year (0·033) with sham, a difference in growth of 0·056 mm/year (95% CI 0·016-0·096; p=0·0064), representing a 14% difference between the avacincaptad pegol 2 mg group and the sham group. Ocular treatment-emergent adverse events in the study eye occurred in 110 (49%) patients in the avacincaptad pegol 2 mg group and 83 (37%) in the sham group. There were no endophthalmitis, intraocular inflammation, or ischaemic optic neuropathy events over 12 months. To month 12, macular neovascularisation in the study eye occurred in 15 (7%) patients in the avacincaptad pegol 2 mg group and nine (4%) in the sham group, with exudative macular neovascularisation occurring in 11 (5%) in the avacincaptad pegol 2 mg group and seven (3%) in the sham group. INTERPRETATION: Monthly avacincaptad pegol 2 mg was well tolerated and showed significantly slower geographic atrophy growth over 12 months than sham treatment, suggesting that avacincaptad pegol might slow disease progression and potentially change the trajectory of disease for patients with geographic atrophy. FUNDING: Iveric Bio, An Astellas Company.

DEFINING "STRONG" VERSUS "WEAK" RESPONSE TO ANTIVASCULAR ENDOTHELIAL GROWTH FACTOR TREATMENT FOR CENTER-INVOLVED DIABETIC MACULAR EDEMA.

BACKGROUND/PURPOSE: To define "strong" versus "weak" antivascular endothelial growth factor (anti-VEGF) treatment response in eyes with center-involved diabetic macular edema (CI-DME). METHODS: Exploratory analyses of three DRCR Retina Network randomized trials of eyes with CI-DME treated with aflibercept, bevacizumab, or ranibizumab. Thresholds of 5-, 10-, and 15-letter gain defined strong visual acuity (VA) response when baseline VA was 20/25-20/32, 20/40-20/63, or 20/80-20/320, respectively. Thresholds of 50, 100, or 200- µ m reduction defined strong anatomical response when baseline central subfield thickness (CST) was <75, ≥75 to <175, or ≥175- µ m above standard thresholds. Additional thresholds from regression equations were calculated. RESULTS: At 24 weeks, outcomes for strong response were achieved by 476 of 958 eyes (50%) for VA and 505 eyes (53%) for CST. At 104 weeks among the 32% of eyes with strong VA and CST response at 24 weeks, 195 of 281 (69%) maintained strong VA and CST response, whereas 20 (7%) had neither strong VA nor strong CST response. Outcomes rates were similar across protocols and when defined using regression equations. CONCLUSION: These phenotypes are suitable for efforts to identify predictive biomarkers for response to anti-VEGF therapy for DME and might facilitate comparison of treatment response among diverse cohorts with DME.

Mega-analysis methods in ENIGMA: The experience of the generalized anxiety disorder working group.

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA-Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega-analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between-country transfer of subject-level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega-analyses.

Evidence for normal extra-axial cerebrospinal fluid volume in autistic males from middle childhood to adulthood.

Autism spectrum disorder has long been associated with a variety of organizational and developmental abnormalities in the brain. An increase in extra-axial cerebrospinal fluid volume in autistic individuals between the ages of 6 months and 4 years has been reported in recent studies. Increased extra-axial cerebrospinal fluid volume was predictive of the diagnosis and severity of the autistic symptoms in all of them, irrespective of genetic risk for developing the disorder. In the present study, we explored the trajectory of extra-axial cerebrospinal fluid volume from childhood to adulthood in both autism and typical development. We hypothesized that an elevated extra-axial cerebrospinal fluid volume would be found in autism persisting throughout the age range studied. We tested the hypothesis by employing an accelerated, multi-cohort longitudinal data set of 189 individuals (97 autistic, 92 typically developing). Each individual had been scanned between 1 and 5 times, with scanning sessions separated by 2-3 years, for a total of 439 T1-weighted MRI scans. A linear mixed-effects model was used to compare developmental, age-related changes in extra-axial cerebrospinal fluid volume between groups. Inconsistent with our hypothesis, we found no group differences in extra-axial cerebrospinal fluid volume in this cohort of individuals 3 to 42 years of age. Our results suggest that extra-axial cerebrospinal fluid volume in autistic individuals is not increased compared with controls beyond four years of age.

Registration-free analysis of diffusion MRI tractography data across subjects through the human lifespan.

Diffusion MRI tractography produces massive sets of streamlines that need to be clustered into anatomically meaningful white-matter bundles. Conventional clustering techniques group streamlines based on their proximity in Euclidean space. We have developed AnatomiCuts, an unsupervised method for clustering tractography streamlines based on their neighboring anatomical structures, rather than their coordinates in Euclidean space. In this work, we show that the anatomical similarity metric used in AnatomiCuts can be extended to find corresponding clusters across subjects and across hemispheres, without inter-subject or inter-hemispheric registration. Our proposed approach enables group-wise tract cluster analysis, as well as studies of hemispheric asymmetry. We evaluate our approach on data from the pilot MGH-Harvard-USC Lifespan Human Connectome project, showing improved correspondence in tract clusters across 184 subjects aged 8-90. Our method shows up to 38% improvement in the overlap of corresponding clusters when comparing subjects with large age differences. The techniques presented here do not require registration to a template and can thus be applied to populations with large inter-subject variability, e.g., due to brain development, aging, or neurological disorders.

Longitudinal changes in cortical thickness in autism and typical development.

The natural history of brain growth in autism spectrum disorders remains unclear. Cross-sectional studies have identified regional abnormalities in brain volume and cortical thickness in autism, although substantial discrepancies have been reported. Preliminary longitudinal studies using two time points and small samples have identified specific regional differences in cortical thickness in the disorder. To clarify age-related trajectories of cortical development, we examined longitudinal changes in cortical thickness within a large mixed cross-sectional and longitudinal sample of autistic subjects and age- and gender-matched typically developing controls. Three hundred and forty-five magnetic resonance imaging scans were examined from 97 males with autism (mean age = 16.8 years; range 3-36 years) and 60 males with typical development (mean age = 18 years; range 4-39 years), with an average interscan interval of 2.6 years. FreeSurfer image analysis software was used to parcellate the cortex into 34 regions of interest per hemisphere and to calculate mean cortical thickness for each region. Longitudinal linear mixed effects models were used to further characterize these findings and identify regions with between-group differences in longitudinal age-related trajectories. Using mean age at time of first scan as a reference (15 years), differences were observed in bilateral inferior frontal gyrus, pars opercularis and pars triangularis, right caudal middle frontal and left rostral middle frontal regions, and left frontal pole. However, group differences in cortical thickness varied by developmental stage, and were influenced by IQ. Differences in age-related trajectories emerged in bilateral parietal and occipital regions (postcentral gyrus, cuneus, lingual gyrus, pericalcarine cortex), left frontal regions (pars opercularis, rostral middle frontal and frontal pole), left supramarginal gyrus, and right transverse temporal gyrus, superior parietal lobule, and paracentral, lateral orbitofrontal, and lateral occipital regions. We suggest that abnormal cortical development in autism spectrum disorders undergoes three distinct phases: accelerated expansion in early childhood, accelerated thinning in later childhood and adolescence, and decelerated thinning in early adulthood. Moreover, cortical thickness abnormalities in autism spectrum disorders are region-specific, vary with age, and may remain dynamic well into adulthood.

Complexity of low-frequency blood oxygen level-dependent fluctuations covaries with local connectivity.

Very low-frequency blood oxygen level-dependent (BOLD) fluctuations have emerged as a valuable tool for describing brain anatomy, neuropathology, and development. Such fluctuations exhibit power law frequency dynamics, with largest amplitude at lowest frequencies. The biophysical mechanisms generating such fluctuations are poorly understood. Using publicly available data from 1,019 subjects of age 7-30, we show that BOLD fluctuations exhibit temporal complexity that is linearly related to local connectivity (regional homogeneity), consistently and significantly covarying across subjects and across gray matter regions. This relationship persisted independently of covariance with gray matter density or standard deviation of BOLD signal. During late neurodevelopment, BOLD fluctuations were unchanged with age in association cortex while becoming more random throughout the rest of the brain. These data suggest that local interconnectivity may play a key role in establishing the complexity of low-frequency BOLD fluctuations underlying functional magnetic resonance imaging connectivity. Stable low-frequency power dynamics may emerge through segmentation and integration of connectivity during development of distributed large-scale brain networks.

Multimodal imaging of white and dark without pressure fundus lesions.

PURPOSE: To describe multimodal imaging findings in patients with dark or white without pressure lesions of the fundus. METHODS: Retrospective observational case series of 10 patients with white or dark without pressure lesions. We analyzed multimodal imaging using spectral domain optical coherence tomography, color and near-infrared fundus photography, and fundus autofluorescence imaging to explore the findings associated with these lesions. RESULTS: All patients had geographic dark or white lesions on clinical examination and color photography, which were either hyporeflective or hyperreflective on near-infrared reflectance imaging, respectively. On optical coherence tomography, these lesions correlated with an abrupt change of the photoreceptor reflectivity, with relative hyporeflectivity of photoreceptor zones (ellipsoid and interdigitation zones, as well as outer segments) within the dark, and relative hyperreflectivity within white lesions. Ten patients underwent fundus autofluorescence, which showed well-defined zones of relative hypo-autofluorescence within the lesion, compared with neighboring uninvolved regions, whether dark or white without pressure. In two patients who had a lesion combining white and dark without pressure, we observed the transition in photoreceptor reflectivity from the dark lesion (hyporeflective) to the white lesion (hyperreflective), relative to the surrounding retina. CONCLUSION: Both white and dark without pressure lesions are associated with changes in outer retinal reflectivity on optical coherence tomography, which occur in opposite directions compared with the surrounding unaffected areas. In the face of normal visual field testing to date, the clinical significance of this finding remains uncertain. Recognition of the optical coherence tomography appearance will help clinicians avoid unnecessary workup of these patients for outer retinal dystrophy or degeneration.

Parsing Brain Network Specialization: A Replication and Expansion of Wang et al. (2014).

One organizing principle of the human brain is hemispheric specialization, or the dominance of a specific function or cognitive process in one hemisphere or the other. Previously, Wang et al. (2014) identified networks putatively associated with language and attention as being specialized to the left and right hemispheres, respectively; and a dual-specialization of the executive control network. However, it remains unknown which networks are specialized when specialization is examined within individuals using a higher resolution parcellation, as well as which connections are contributing the most to a given network's specialization. In the present study, we estimated network specialization across three datasets using the autonomy index and a novel method of deconstructing network specialization. After examining the reliability of these methods as implemented on an individual level, we addressed two hypotheses. First, we hypothesized that the most specialized networks would include those associated with language, visuospatial attention, and executive control. Second, we hypothesized that within-network contributions to specialization would follow a within-between network gradient or a specialization gradient. We found that the majority of networks exhibited greater within-hemisphere connectivity than between-hemisphere connectivity. Among the most specialized networks were networks associated with language, attention, and executive control. Additionally, we found that the greatest network contributions were within-network, followed by those from specialized networks.

Small-Gauge Vitrectomy for Macular Surgery Using a Systematic Approach to Wound Closure: 27-Gauge vs 25-Gauge.

Purpose: To evaluate the effectiveness of and to compare vitrectomy performed with 25-gauge or 27-gauge instrumentation for macular surgery by assessing the surgical duration, wound closure, and complication rate using a systematic approach to wound closure. Methods: In this retrospective chart review, 125 25-gauge and 125 27-gauge consecutive small-gauge vitrectomy surgeries for epiretinal membrane, macular hole, vitreomacular adhesion, or a combination were analyzed during and immediately after surgery. Wound closure was performed using a systematic protocol. Results: Baseline characteristics were not statistically different between the 2 groups. The surgical duration was similar with 25-gauge vitrectomy and 27-gauge vitrectomy (P = .07). Although spontaneous wound closure was common in both groups, it was more common in the 27-gauge group (P = .22). Intraoperative and postoperative complications were uncommon in both groups. Conclusions: Findings show that 27-gauge vitrectomy is a safe, effective alternative to the more commonly used 25-gauge vitrectomy for macular surgery. Less manipulation was required to achieve wound closure with 27-gauge vitrectomy using a standardized wound-closure protocol. Smaller 27-gauge vitrectomy did not increase surgical time or complications over 25-gauge vitrectomy for macular surgery.

Reduced lateralization of multiple functional brain networks in autistic males.

BACKGROUND: Autism spectrum disorder has been linked to a variety of organizational and developmental deviations in the brain. One such organizational difference involves hemispheric lateralization, which may be localized to language-relevant regions of the brain or distributed more broadly. METHODS: In the present study, we estimated brain hemispheric lateralization in autism based on each participant's unique functional neuroanatomy rather than relying on group-averaged data. Additionally, we explored potential relationships between the lateralization of the language network and behavioral phenotypes including verbal ability, language delay, and autism symptom severity. We hypothesized that differences in hemispheric asymmetries in autism would be limited to the language network, with the alternative hypothesis of pervasive differences in lateralization. We tested this and other hypotheses by employing a cross-sectional dataset of 118 individuals (48 autistic, 70 neurotypical). Using resting-state fMRI, we generated individual network parcellations and estimated network asymmetries using a surface area-based approach. A series of multiple regressions were then used to compare network asymmetries for eight significantly lateralized networks between groups. RESULTS: We found significant group differences in lateralization for the left-lateralized Language (d = -0.89), right-lateralized Salience/Ventral Attention-A (d = 0.55), and right-lateralized Control-B (d = 0.51) networks, with the direction of these group differences indicating less asymmetry in autistic males. These differences were robust across different datasets from the same participants. Furthermore, we found that language delay stratified language lateralization, with the greatest group differences in language lateralization occurring between autistic males with language delay and neurotypical individuals. CONCLUSIONS: These findings evidence a complex pattern of functional lateralization differences in autism, extending beyond the Language network to the Salience/Ventral Attention-A and Control-B networks, yet not encompassing all networks, indicating a selective divergence rather than a pervasive one. Moreover, we observed an association between Language network lateralization and language delay in autistic males.

Supplemental Intravitreal Ranibizumab Injections in Eyes Treated with the Port Delivery System with Ranibizumab in the Archway Trial.

PURPOSE: To determine the proportion and characteristics of eyes with neovascular age-related macular degeneration (nAMD) treated with the Port Delivery System with ranibizumab (PDS) that receive supplemental intravitreal ranibizumab injections due to changes in best-corrected visual acuity (BCVA) and/or central subfield thickness (CST), and to investigate the safety and efficacy of supplemental injections in eyes with the PDS. DESIGN: Post-hoc analyses of data from the phase 3, randomized, multicenter, open-label, active-comparator Archway trial (NCT03677934). PARTICIPANTS: Adults with nAMD diagnosed within 9 months of screening previously responsive to anti-vascular endothelial growth factor (anti-VEGF) therapy. INTERVENTION: 418 patients were randomized to the PDS with ranibizumab 100 mg/mL with fixed refill-exchanges every 24 weeks (Q24W) or monthly intravitreal ranibizumab 0.5 mg for 96 weeks. RESULTS: Of the 246 eyes treated with the PDS Q24W and assessed for supplemental treatment criteria, the vast majority (94.6%-98.4%) did not receive supplemental treatment during each retreatment interval, with 87.4% not receiving supplemental treatment at any point during the trial. Of the 31 eyes receiving supplemental treatment, 58.1% received 1 injection and 32.3% received 2. At baseline, eyes receiving supplemental treatment were significantly more likely to have thicker retinas (mean CST 370.5µm vs 304.4µm; P = 0.0001), subretinal fluid (54.8% vs 21.2%; P < 0.0001), and larger pigment epithelial detachment height (215.7µm versus 175.9µm; P = 0.003). These features have previously been associated with difficult-to-treat nAMD. Whereas BCVA and CST generally remained constant throughout the trial in eyes without supplemental treatment, the small number of eyes receiving supplemental treatment on average lost 1 line of vision from baseline to week 96 (mean -5.7 Early Treatment Diabetic Retinopathy Study score letters) and CST continued to increase over time. Absolute BCVA at week 96 was similar irrespective of supplemental treatment status (71.1 and 73.7 letters). BCVA and CST generally improved within 28 days of supplemental treatment. CONCLUSIONS: Although the PDS Q24W effectively maintains vision and retinal stability in most eyes with nAMD, a small proportion of patients with features of difficult-to-treat nAMD may benefit from supplemental intravitreal anti-VEGF injections and initial close monitoring is recommended.

Anti-VEGF Pharmaceutical Prior Authorization in Retina Practices.

Importance: Anti-vascular endothelial growth factor (VEGF) intravitreal injections, a mainstay of treatment for many retinal diseases to optimize visual outcomes, have been included in prior authorization (PA) initiatives. However, if clinicians are extremely accurate in their use of anti-VEGF medications, such administrative burdens may need reconsideration. Objective: To quantify PA for anti-VEGF medications (aflibercept, ranibizumab, and bevacizumab) that were approved and determine associated administrative burdens experienced by retina practices. Design, Setting, and Participants: Prospective multicenter quality improvement study conducted from January 2022 through June 2022, and participants were 9 private retina practices across the US. Main Outcomes and Measures: Overall rate of approval of PA requests, reasons for requesting PA, and overall rate of delay of care resulting from PA procedures. Results: In total, 2365 PA requests were recorded, 2225 of which met inclusion criteria. Overall, 2140 (96.2%) requests were approved. The most common reason for requesting PA, at 64% (1423 of 2225 requests), was reauthorization for a previously utilized medication. Of the 2140 approvals, 59.6% (1277) resulted in a delay in care greater than 24 hours, and 40% (863) were given on the date of service. In a granular analysis of a subset of delayed approvals, 23.9% (173 of 725) were approved within 1 day, 15.9% (115 of 725) were approved within 2 to 3 days, 21.5% (156 of 725) were approved within 4 to 7 days, 26.3% (191 of 725) were approved within 8 to 31 days, and 12.4% (90 of 725) were approved within more than 31 days. Overall, PA denial for step therapy was 2.9% (65 of 2225) of requests and uncovered diagnoses was 0.9% (20 of 2225) of requests. The median staff time spent to obtain a single PA was 100 (range, 0-200) minutes. Conclusions and Relevance: In this study, PA requests were almost always approved but led to a delay in patient care in most patients. The current study suggests that the PA process may not be effective for retina specialists if these results can be generalized to other practices in the US and if less burdensome and less costly approaches could result in similar approval rates. Potential short-term solutions may include eliminating the PA process for bevacizumab and reauthorizations for established patients.

No difference in extra-axial cerebrospinal fluid volumes across neurodevelopmental and psychiatric conditions in later childhood and adolescence.

BACKGROUND: While autism spectrum disorder has been associated with various organizational and developmental aberrations in the brain, an increase in extra-axial cerebrospinal fluid volume has recently garnered attention. A series of studies indicate that an increased volume between the ages of 6 months and 4 years was both predictive of the autism diagnosis and symptom severity regardless of genetic risk for the condition. However, there remains a minimal understanding regarding the specificity of an increased volume of extra-axial cerebrospinal fluid to autism. METHODS: In the present study, we explored extra-axial cerebrospinal fluid volumes in children and adolescents ages 5-21 years with various neurodevelopmental and psychiatric conditions. We hypothesized that an elevated extra-axial cerebrospinal fluid volume would be found in autism compared with typical development and the other diagnostic group. We tested this hypothesis by employing a cross-sectional dataset of 446 individuals (85 autistic, 60 typically developing, and 301 other diagnosis). An analysis of covariance was used to examine differences in extra-axial cerebrospinal fluid volumes between these groups as well as a group by age interaction in extra-axial cerebrospinal fluid volumes. RESULTS: Inconsistent with our hypothesis, we found no group differences in extra-axial cerebrospinal fluid volume in this cohort. However, in replication of previous work, a doubling of extra-axial cerebrospinal fluid volume across adolescence was found. Further investigation into the relationship between extra-axial cerebrospinal fluid volume and cortical thickness suggested that this increase in extra-axial cerebrospinal fluid volume may be driven by a decrease in cortical thickness. Furthermore, an exploratory analysis found no relationship between extra-axial cerebrospinal fluid volume and sleep disturbances. CONCLUSIONS: These results indicate that an increased volume of extra-axial cerebrospinal fluid may be limited to autistic individuals younger than 5 years. Additionally, extra-axial cerebrospinal fluid volume does not differ between autistic, neurotypical, and other psychiatric conditions after age 4.

High-Dose Aflibercept for Neovascular AMD and DME in Suboptimal Responders to Standard-Dose Aflibercept.

Purpose: To assess the effect of higher dose (HD) aflibercept on visual acuity (VA), optical coherence tomography outcomes, and injection burden in eyes with neovascular age-related macular degeneration (nAMD) or diabetic macular edema (DME) that responded suboptimally to standard-dose aflibercept. Methods: This retrospective analysis included eyes with clinically significant disease activity on monthly therapy (AMT) (injection interval ≤35 days) or clinically significant increased activity on extension (IAE) (injection interval >36 days) that were switched from aflibercept 2 mg to aflibercept HD (3 mg to 4 mg). Outcomes were assessed at baseline, after injections 1 through 4, and at 6, 9, and 12 months. Results: Overall, 318 eyes of 288 adult patients were analyzed (eyes with nAMD: 59 AMT, 147 IAE; eyes with DME: 50 AMT, 62 IAE). Most of the study cohort received aflibercept HD 3 mg (nAMD: 73% AMT and 58% IAE; DME: 49% AMT and 68% IAE); the remainder received 4 mg. The mean best VA improved significantly with AMT and was maintained with IAE. In all groups, the central subfield thickness decreased significantly and the mean injection intervals increased or remained stable. No new safety signals were observed. Conclusions: Aflibercept HD might improve outcomes while decreasing treatment burden for eyes that respond suboptimally to standard dosing.

Evidence for a Compensatory Relationship between Left- and Right-Lateralized Brain Networks.

The two hemispheres of the human brain are functionally asymmetric. At the network level, the language network exhibits left-hemisphere lateralization. While this asymmetry is widely replicated, the extent to which other functional networks demonstrate lateralization remains a subject of Investigation. Additionally, it is unknown how the lateralization of one functional network may affect the lateralization of other networks within individuals. We quantified lateralization for each of 17 networks by computing the relative surface area on the left and right cerebral hemispheres. After examining the ecological, convergent, and external validity and test-retest reliability of this surface area-based measure of lateralization, we addressed two hypotheses across multiple datasets (Human Connectome Project = 553, Human Connectome Project-Development = 343, Natural Scenes Dataset = 8). First, we hypothesized that networks associated with language, visuospatial attention, and executive control would show the greatest lateralization. Second, we hypothesized that relationships between lateralized networks would follow a dependent relationship such that greater left-lateralization of a network would be associated with greater right-lateralization of a different network within individuals, and that this pattern would be systematic across individuals. A language network was among the three networks identified as being significantly left-lateralized, and attention and executive control networks were among the five networks identified as being significantly right-lateralized. Next, correlation matrices, an exploratory factor analysis, and confirmatory factor analyses were used to test the second hypothesis and examine the organization of lateralized networks. We found general support for a dependent relationship between highly left- and right-lateralized networks, meaning that across subjects, greater left lateralization of a given network (such as a language network) was linked to greater right lateralization of another network (such as a ventral attention/salience network) and vice versa. These results further our understanding of brain organization at the macro-scale network level in individuals, carrying specific relevance for neurodevelopmental conditions characterized by disruptions in lateralization such as autism and schizophrenia.

Binocular rivalry in autistic and socially anxious adults.

Background: Social anxiousness is a pervasive symptom in both social anxiety disorder and autism spectrum conditions. Binocular rivalry, which occurs when different images are presented to each eye, has been used to explore how visual and cognitive processing differs across various clinical diagnoses. Previous studies have separately explored whether individuals with autism or anxiety experience binocular rivalry in ways that are different from neurotypical individuals. Methods: We applied rivalry paradigms that are similar to those used in previous studies of autism and general anxiety to individuals experiencing symptoms of social anxiousness at clinical or subclinical levels. We also incorporated rivalrous stimuli featuring neutral and emotional facial valances to explore potential overlap of social processing components in social anxiety and autism. Results: We hypothesized that higher levels of social anxiousness would increase binocular rivalry switch rates and that higher levels of autistic traits would decrease switch rates. However, stimulus condition did not affect switch rates in either diagnostic group, and switch rate was not significantly predictive of dimensional measures of either autism or social anxiety. Discussion: This may suggest a common mechanism for atypical visual cognition styles previously associated with social anxiety and autism. Alternatively, differences in switch rates may only emerge at higher trait levels than reported by the participants in our studies. Furthermore, these findings may be influenced by sex differences in our unique sample.

Precision Brain Morphometry Using Cluster Scanning.

Measurement error limits the statistical power to detect group differences and longitudinal change in structural MRI morphometric measures (e.g., hippocampal volume, prefrontal thickness). Recent advances in scan acceleration enable extremely fast T1-weighted scans (~1 minute) to achieve morphometric errors that are close to the errors in longer traditional scans. As acceleration allows multiple scans to be acquired in rapid succession, it becomes possible to pool estimates to increase measurement precision, a strategy known as "cluster scanning." Here we explored brain morphometry using cluster scanning in a test-retest study of 40 individuals (12 younger adults, 18 cognitively unimpaired older adults, and 10 adults diagnosed with mild cognitive impairment or Alzheimer's Dementia). Morphometric errors from a single compressed sensing (CS) 1.0mm scan with 6x acceleration (CSx6) were, on average, 12% larger than a traditional scan using the Alzheimer's Disease Neuroimaging Initiative (ADNI) protocol. Pooled estimates from four clustered CSx6 acquisitions led to errors that were 34% smaller than ADNI despite having a shorter total acquisition time. Given a fixed amount of time, a gain in measurement precision can thus be achieved by acquiring multiple rapid scans instead of a single traditional scan. Errors were further reduced when estimates were pooled from eight CSx6 scans (51% smaller than ADNI). Neither pooling across a break nor pooling across multiple scan resolutions boosted this benefit. We discuss the potential of cluster scanning to improve morphometric precision, boost statistical power, and produce more sensitive disease progression biomarkers.