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Vision is the most powerful sense guiding our interaction with the environment. Its process starts with the retinal image as input and results in visually guided behaviors as output. This paper summarizes insights I gained over >40 years dealing with clinical ophthalmology, visual science, and vision rehabilitation, disciplines that all involve vision, but from different points of view. The retinal image contains 2-dimensional forms that have no inherent meaning. The brain matches this input to stored concepts, to create a Mental Model that is filled with 3-dimensional objects that are meaningful and linked to other senses. Ultimately this leads to the output of goal-directed visually guided behavior. The processes involved are too complex to be covered by a single practitioner. Optimal vision rehabilitation requires teamwork that includes contributions from various professions. It also requires an understanding, as well as possible, of the cerebral processes involved. The visual sciences study mostly the input-driven process from retinal image to visual percepts. Their studies deal mostly with groups and group averages and only occasionally with individual disease conditions. Clinical ophthalmology deals mostly with individuals, rather than group averages. The motto of the American Academy of Ophthalmology reminds us that the end point of patient care goes beyond "preserving sight." It also includes "empowering lives" by creating the conditions for goal-directed interaction with the environment through visually directed behavior. Traditionally, the study of vision has mainly involved the conscious part of vision, handled mostly in the ventral stream. However, the subconscious part of vision, handled mostly in the dorsal stream must also be considered. This is further stimulated by the demands of computer vision, image processing, and artificial intelligence. Vision rehabilitation traditionally deals with the input side through better illumination and various magnification devices. This is the domain of low vision aids. Increasingly, however, it must also address the output side, and the involvement of other senses (braille, long cane, and talking books). This requires better understanding of the goal-directed higher visual processes. The supplemental material covers the development of numerical scales to quantify not only visual acuity but also visual abilities, and the use of different tests. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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Purpose: Geographic atrophy (GA) impacts both patients and caregivers, yet little is understood about their respective burdens. The MOSAIC study aimed to identify the clinical, emotional, and financial burden among patients with GA and caregivers. Methods: A total of 28 patients with GA and 17 caregivers from the United States (US), the United Kingdom, and Australia participated in individualized qualitative interviews followed by a cross-sectional quantitative survey of 102 patients and 102 caregivers in the US. Interview transcripts were analyzed to develop conceptual models, which were then used to guide the design of quantitative surveys. Data were described at the item level and score level when appropriate (National Eye Institute Visual Function Questionnaire [NEI VFQ]-39 and Zarit Burden Interview [ZBI]). For the patient/caregiver dyad sample, the association between the NEI VFQ-39 scores and ZBI score was explored through correlation coefficients and scatterplots. Results: GA had a substantial impact on patients' vision-related quality of life, activities of daily living, and instrumental activities of daily living. There was considerable overlap between perspectives and key concerns identified by patients and caregivers. Eighty-three percent of caregivers reported having to drive patients to appointments due to limited patient mobility, for example, and 41% reported a change in their employment status after becoming a caregiver, with 50% of them unable to work due to caregiving. The burden of patients and caregivers had a correlation ranging from -0.63 to -0.21 between NEI VFQ-39 subscale and composite scores and ZBI score. Conclusion: This study confirms the paucity of support for both patients with GA and caregivers. Both groups require expanded access to financial, social, and mental health resources.

What is this summary about? People with geographic atrophy, also called GA, can lose their eyesight and have a hard time driving, reading, and recognizing faces. This can worsen their quality of life. Often, people with GA need someone to care for them. The MOSAIC study was done to find out how GA affects health, happiness, and finances of people with GA and their caregivers. What were the results? One hundred and two people with GA and 102 caregivers in the United States were interviewed. The average age of people with GA was 68 years and of caregivers was 46 years. The findings showed that most people with GA did not drive because of their poor eyesight and instead counted on their caregivers to drive them to doctor appointments and other places. They also had a reading and doing things around their home because of their worsened eyesight. Both people with GA and caregivers said they felt stressed. They both worried about spending money on things they need to make living with GA easier. They also felt stressed about their finances because they could not work as much. People with GA worried most about losing their independence and caregivers worried most about the future of their loved one with GA. What do the results mean? This study showed that GA has a serious effect on people's health and quality of life while also having a major impact on their caregivers.

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BACKGROUND: Accurate visual information is needed to guide and perform efficient movements in daily life. AIMS: To investigate the relation between visual functions, functional vision, and bimanual function in children with unilateral cerebral palsy (uCP). METHODS AND PROCEDURES: In 49 children with uCP (7-15 y), we investigated the relation between stereoacuity (Titmus Stereo Fly test), visual perception (Test of Visual Perceptual Skills), visuomotor integration (Beery Buktenica Test of Visual-Motor Integration) and functional vision (Flemish cerebral visual impairment questionnaire) with bimanual dexterity (Tyneside Pegboard Test), bimanual coordination (Kinarm exoskeleton robot, Box opening task), and functional hand use (Children's Hand-use Experience Questionnaire; Assisting Hand Assessment) using correlations (rs) and elastic-net regularized regressions (d). OUTCOMES AND RESULTS: Visual perception correlated with bimanual coordination (rs=0.407-0.436) and functional hand use (rs=0.380-0.533). Stereoacuity (rs=-0.404), visual perception (rs=-0.391 to -0.620), and visuomotor integration (rs=-0.377) correlated with bimanual dexterity. Functional vision correlated with functional hand use (rs=-0.441 to -0.458). Visual perception predicted bimanual dexterity (d=0.001-0.315), bimanual coordination (d=0.004-0.176), and functional hand use (d=0.001-0.345), whereas functional vision mainly predicted functional hand use (d=0.001-0.201). CONCLUSIONS AND IMPLICATIONS: Visual functions and functional vision are related to bimanual function in children with uCP highlighting the importance of performing extensive visual assessment to better understand children's difficulties in performing bimanual tasks. WHAT THIS PAPER ADDS: Previous findings showed that up to 62 % of children with unilateral cerebral palsy (uCP) present with visual impairment, which can further compromise their motor performance. However, the relation between visual and motor function has hardly been investigated in this population. This study makes a significant contribution to the literature by comprehensively investigating the multi-level relation between the heterogenous spectrum of visual abilities and bimanual function in children with uCP. We found that mainly decreased visual perception was related to decreased bimanual dexterity, bimanual coordination, and functional hand use while impairments in functional vision were only related to decreased functional hand use. Additionally, elastic-net regression models showed that visual assessments can predict bimanual function in children with uCP, however, effect sizes were only tiny to small. With our study, we demonstrated a relation between visual functions and bimanual function in children with uCP. These findings suggest the relevance of thoroughly examining visual functions in children with uCP to identify the presence of visual impairments that may further compromise their bimanual function.

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BACKGROUND: Age-related vision changes significantly contribute to fatal crashes at night among older drivers. However, the effects of lighting conditions on age-related vision changes and associated driving performance remain unclear. OBJECTIVE: This pilot study examined the associations between visual function and driving performance assessed by a high-fidelity driving simulator among drivers 60 and older across 3 lighting conditions: daytime (photopic), nighttime (mesopic), and nighttime with glare. METHODS: Active drivers aged 60 years or older participated in visual function assessments and simulated driving on a high-fidelity driving simulator. Visual acuity (VA), contrast sensitivity function (CSF), and visual field map (VFM) were measured using quantitative VA, quantitative CSF, and quantitative VFM procedures under photopic and mesopic conditions. VA and CSF were also obtained in the presence of glare in the mesopic condition. Two summary metrics, the area under the log CSF (AULCSF) and volume under the surface of VFM (VUSVFM), quantified CSF and VFM. Driving performance measures (average speed, SD of speed [SDspeed], SD of lane position (SDLP), and reaction time) were assessed under daytime, nighttime, and nighttime with glare conditions. Pearson correlations determined the associations between visual function and driving performance across the 3 lighting conditions. RESULTS: Of the 20 drivers included, the average age was 70.3 years; 55% were male. Poor photopic VA was significantly correlated with greater SDspeed (r=0.26; P<.001) and greater SDLP (r=0.31; P<.001). Poor photopic AULCSF was correlated with greater SDLP (r=-0.22; P=.01). Poor mesopic VUSFVM was significantly correlated with slower average speed (r=-0.24; P=.007), larger SDspeed (r=-0.19; P=.04), greater SDLP (r=-0.22; P=.007), and longer reaction times (r=-0.22; P=.04) while driving at night. For functional vision in the mesopic condition with glare, poor VA was significantly correlated with longer reaction times (r=0.21; P=.046) while driving at night with glare; poor AULCSF was significantly correlated with slower speed (r=-0.32; P<.001), greater SDLP (r=-0.26; P=.001) and longer reaction times (r=-0.2; P=.04) while driving at night with glare. No other significant correlations were observed between visual function and driving performance under the same lighting conditions. CONCLUSIONS: Visual functions differentially affect driving performance in different lighting conditions among older drivers, with more substantial impacts on driving during nighttime, especially in glare. Additional research with larger sample sizes is needed to confirm these results.

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This paper explores whether a structured history-taking tool yields useful descriptions of children's looking skills. Parents of 32 children referred to a specialist communication clinic reported their child's looking skills using the Functional Vision for Communication Questionnaire (FVC-Q), providing descriptions of single object fixation, fixation shifts between objects and fixation shifts from object to person. Descriptions were compared with clinical assessment. 24/32 children were reported to have some limitation in fixation. Limitation was subsequently seen in 30/32 children. Parental report and assessment agreed fully in 23/32 (72%). The largest area of discrepancy was object-person fixation shifts, with five children not observed to show this behavior despite its being reported. Findings indicate a structured questionnaire yields description of fixations, which correspond well with clinical assessment. Descriptions supported discussion between parents and clinicians. It is proposed that the FVC-Q is a valuable tool in supporting clinicians in eliciting information about fixation skills.

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Purpose: X-linked retinoschisis (XLRS), due to loss-of-function mutations in the retinoschisin (RS1) gene, is characterized by a modest to severe decrease in visual acuity. Clinical trials for XLRS utilizing intravitreal (IVT) gene therapy showed ocular inflammation. We conducted a subretinal dose-response preclinical study using rAAV2tYF-CB-hRS1 utilizing the Rs1 knockout (Rs1-KO) mouse to investigate short- and long-term retinal rescue after subretinal gene delivery. Methods: Rs1-KO mice were subretinally injected with 2 µL of rAAV2tYF-CB-hRS1 vector with 8E9 viral genomes (vg)/eye, 8E8 vg/eye, 8E7 vg/eye, or sham injection, and compared to untreated eyes. Reconstitution of human RS1 protein was detected using western blotting. Analysis of retinal function by electroretinography (ERG) and structural analysis by optical coherence tomography (OCT) were performed at 1, 2, 3, 5, 7, and 12 months post injection (MPI). Immunohistochemistry (IHC) was performed to evaluate cone rescue on the cellular level. Functional vision was evaluated using a visually guided swim assay (VGSA). Results: Western blotting analysis showed human RS1 protein expression in a dose-dependent manner. Quantification of western blotting showed that the RS1 protein expression in mice treated with the 8E8 vg dose was near the wild-type (WT) expression levels. ERG demonstrated dose-dependent effects: At 1 MPI the 8E8 vg dose treated eyes had higher light-adapted (LA) ERG amplitudes in 3.0 flash and 5 Hz flicker compared to untreated (p < 0.0001) and sham-treated eyes (p < 0.0001) which persisted until the 12 MPI endpoint, consistent with improved cone function. ERG b-wave amplitudes were higher in response to dark-adapted (DA) 0.01 dim flash and 3.0 standard combined response (SCR) compared to sham-treated (p < 0.01) and untreated eyes (p < 0.001) which persisted until 3 MPI, suggesting short-term improvement of the rod photoreceptors. All injections, including sham-treated, resulted in a cyst severity score of 1 (no cavities), with significant reductions compared to untreated eyes up to 3 MPI (p < 0.05). The high and low dose groups showed inconsistent ERG improvements, despite reduced cyst severity, emphasizing the dose-dependent nature of gene augmentation's efficacy and the tenuous connection between cyst reduction and ERG improvement. IHC data showed a significant cone rescue in eyes treated with the 8E8 vg dose compared to sham-treated and untreated eyes. VGSA showed better functional vision in 8E8 vg dose treated mice. Eyes treated with the highest dose showed occasional localized degeneration in the outer nuclear layer. Conclusion: Our data suggest that a dose of 8E8 vg/eye subretinally improves retinal function and structure in the Rs1-KO mouse. It improves cone function, rod function, and reduces cyst severity. Sham treatment resolves schisis cysts, but 8E8 vg/eye is needed for optimal retinal electrical function rescue. These findings offer a promising path for clinical translation to human trials.

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PURPOSE: The purpose of this study is to investigate test-retest reliability and agreement of the quantitative contrast sensitivity function test (qCSF) in the retina clinic. METHODS: A total of 121 right eyes of 121 patients were tested and consecutively re-tested with qCSF in the retina clinic. Outcomes included area under the logarithm of contrast sensitivity function curve (AULCSF), contrast acuity, and contrast sensitivity thresholds at 1-18 cycles per degree (cpd). Test-retest means were compared with paired t-test, variability was compared with the Brown-Forsythe test, and intraclass correlation coefficient (ICC) and Bland Altman plots evaluated reliability and agreement. RESULTS: Mean test-retest differences for all qCSF metrics ranged from 0.02 to 0.05 log units without statistically significant differences in variability. Standard deviations ranged from 0.08 to 0.14. Coefficients of repeatability ranged from 0.16 to 0.27 log units. ICC > 0.9 for all metrics except 1cpd (ICC = 0.84, all p < 0.001); AULCSF ICC = 0.971. CONCLUSION: qCSF-measured contrast sensitivity shows great test-retest repeatability and agreement in the retina clinic.

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PURPOSE: The purpose of this study was to develop a visually guided swim assay (VGSA) for measuring vision in mouse retinal disease models comparable to the multi-luminance mobility test (MLMT) utilized in human clinical trials. METHODS: Three mouse retinal disease models were studied: Bardet-Biedl syndrome type 1 (Bbs1M390R/M390R), n = 5; Bardet-Biedl syndrome type 10 (Bbs10-/-), n = 11; and X linked retinoschisis (retinoschisin knockout; Rs1-KO), n = 5. Controls were normally-sighted mice, n = 10. Eyeless Pax6Sey-Dey mice, n = 4, were used to determine the performance of animals without vision in VGSA. RESULTS: Eyeless Pax6Sey-Dey mice had a VGSA time-to-platform (TTP) 7X longer than normally-sighted controls (P < 0.0001). Controls demonstrated no difference in their TTP in both lighting conditions; the same was true for Pax6Sey-Dey. At 4-6 M, Rs1-KO and Bbs10-/- had longer TTP in the dark than controls (P = 0.0156 and P = 1.23 × 10-8, respectively). At 9-11 M, both BBS models had longer TTP than controls in light and dark with times similar to Pax6Sey-Dey (P < 0.0001), demonstrating progressive vision loss in BBS models, but not in controls nor in Rs1-KO. At 1 M, Bbs10-/- ERG light-adapted (cone) amplitudes were nonrecordable, resulting in a floor effect. VGSA did not reach a floor until 9-11 M. ERG combined rod/cone b-wave amplitudes were nonrecordable in all three mutant groups at 9-11 M, but VGSA still showed differences in visual function. ERG values correlate non-linearly with VGSA, and VGSA measured the continual decline of vision. CONCLUSION: ERG is no longer a useful endpoint once the nonrecordable level is reached. VGSA differentiates between different levels of vision, different ages, and different disease models even after ERG is nonrecordable, similar to the MLMT in humans.

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Objective: Appropriate functional vision is vital for the development of visually impaired (VI) children. However, the literature currently lacks a performance-based tool for assessing functional vision, unlike the existing self-reported tools. The objective of this study is to develop and conduct a clinimetric study on a Performance-Based Functional Vision Tool (PB-FVT) specifically designed for VI children aged 3-7 and 7-10 years old. Methods: This methodological study was conducted to assess the clinimetric properties of the PB-FVT. The assessment included face validity (evaluated through cognitive interviews and an Impact Score >1.5), content validity (with criteria including content validity ratio >0.63, item content validity index >0.78, scale content validity index or average >0.8, and Kappa value >0.7), criterion validity (assessed through a concurrent test using visual acuity scores), construct validity (utilizing the known group method), relative reliability (measured by the intra-class correlation coefficient), absolute reliability (determined by the standard error of measurement and minimal detectable changes), interpretability, responsiveness, sensitivity, and specificity (analyzed via ROC curve analysis). Results: The PB-FVT was developed with 32 items, divided into five components: activities of daily living, instrumental activities of daily living, education, play, and social interaction. The results indicate that the scale demonstrates suitability in terms of validity, reliability, and other measurement characteristics. Conclusions: The valid and reliable PB-FVT may accurately assess the level of functional vision during early childhood, helping to prevent negative impacts on a child's overall development. By utilizing the PB-FVT, any functional vision impairments can be identified appropriately, enabling the planning and implementation of effective rehabilitation interventions.

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Context: Cerebral visual impairment (CVI) is an overarching term, defined as a brain-based visual impairment with onset in childhood, unexplained by an ocular disorder and associated with unique visual and behavioral characteristics. Good vision and awareness of visual function in a child are highly essential as neuroplasticity is maximum in the first three years of life and response to intervention is utmost in this period. Awareness is lacking regarding CVI, and the diagnosis is largely missed. This can be easily addressed if a structured approach is employed. Purpose: This study aims to evaluate the etiology and radiological correlation with the severity of CVI and outcome after structured intervention in children with CVI. Settings and Design: Prospective-interventional study. Methods and Material: Children attending the Child Development Centre (CDC) of a tertiary care hospital in North Karnataka and diagnosed with CVI in the age group of six months to 12 years and meeting the sampling criteria were screened and enrolled consecutively after obtaining parental consent/assent. Statistical analysis used is nonparametric test with SPSS software. Results: Age showed a significant association with the phase of CVI. Perinatal insult was associated significantly with the severity of CVI. Magnetic resonance imaging (MRI) findings did not hamper the recovery of CVI. Conclusions: Enrolment in early intervention programs tailored according to child's specific needs should be encouraged, with stress on ophthalmic screening of preterm and high-risk babies with perinatal hypoxia and history of convulsions, as early as six months.

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Hereditary retinal degeneration (RD) is often associated with excessive cGMP signalling in photoreceptors. Previous research has shown that inhibition of cGMP-dependent protein kinase G (PKG) can reduce photoreceptor loss in two different RD animal models. In this study, we identified a PKG inhibitor, the cGMP analogue CN238, which preserved photoreceptor viability and functionality in rd1 and rd10 mutant mice. Surprisingly, in explanted retinae, CN238 also protected retinal ganglion cells from axotomy-induced retrograde degeneration and preserved their functionality. Furthermore, kinase activity-dependent protein phosphorylation of the PKG target Kv1.6 was reduced in CN238-treated rd10 retinal explants. Ca2+-imaging on rd10 acute retinal explants revealed delayed retinal ganglion cell repolarization with CN238 treatment, suggesting a PKG-dependent modulation of Kv1-channels. Together, these results highlight the strong neuroprotective capacity of PKG inhibitors for both photoreceptors and retinal ganglion cells, illustrating their broad potential for the treatment of retinal diseases and possibly neurodegenerative diseases in general.

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Purpose: Children with cerebral visual impairment (CVI) present with delayed developmental milestones. Pediatricians and pediatric neurologists are usually the first point of contact, and eye exam largely remains referral based. This study documented the visual concerns reported by parents of children with CVI visiting a pediatric neurology clinic. Additionally, we investigated the association between visual concerns, functional vision measures and visual functions. Patients and Methods: A cross-sectional study was undertaken in children with CVI (chronological age range: 7 months-7 years). Visual concerns reported by the parents/caregivers were documented as open-ended statements. Additionally, a functional vision assessment was conducted using the CVI Range instrument with phase 1, 2 and 3 indicating low, moderate and high visual functioning, respectively. Grating acuity and contrast sensitivity were measured using Teller acuity cards-II and Ohio contrast cards respectively. Results: A total of 73 children (mean age of 2.84 ± 1.87 years) were recruited. Sixty-eight parents reported visual concerns that were broadly grouped into 14 unique concerns. Nineteen parents (27.9%) reported more than one visual concern. Difficulty maintaining eye contact and recognizing faces were the top two visual concerns in phases 1 and 2. Missing objects in the lower visual field was the top concern in phase 3. A larger number of visual concerns were reported in phase 1 (43%) than phase 2 (40.6%) and phase 3 (16.2%). Multiple regression analysis revealed that grating acuity, contrast sensitivity and chronological age were able to predict the functional vision, F (3, 55) = 63.0, p < 0.001, r2 = 0.77. Conclusion: Targeted questions enquiring about eye contact and face recognition can be included in history elicitation in children with CVI in pediatric neurology clinics. In the presence of visual concerns, it will be important to assess grating acuity and contrast sensitivity. A poor functional vision score requires referral for eye examination and vision rehabilitation services.

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Purpose: Coronavirus disease 2019 (COVID-19) pandemic affected the in-person rehabilitation/habilitation services in families with children with cerebral visual impairment (CVI) in India. This study aimed to develop a structured and family-centered telerehabilitation model alongside conventional in-person intervention in children with CVI to observe its feasibility in the Indian population. Methods: This pilot study included 22 participants with a median age of 2.5 years (range: 1-6) who underwent a detailed comprehensive eye examination followed by functional vision assessment. The visual function classification system (VFCS) was administered to the children and the structured clinical question inventory (SCQI) to the parents. Every participant underwent 3 months of telerehabilitation including planning, training, and monitoring by experts. At 1 month, the parental care and ability (PCA) rubric was administered to the parents. After 3 months, in an in-person follow-up, all the measures were reassessed for 15 children. Results: After 3 months of Tele-rehabilitation there were significant improvements noted in PCA rubric scores (P<0.05). Also, statistically significant improvements were noted in functional vision measured using SCQI and VFCS scores (P<0.05) compared to baseline. Conclusion: The outcomes of the study provide the first steps towards understanding the use of a novel tele-rehabilitation model in childhood CVI along-side conventional face-to-face intervention. The added role of parental involvement in such a model is highly essential.

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Cataract is a leading cause of visual impairment in old age. Lens opacification is notoriously associated with several geriatric conditions, including frailty, fall risk, depression and cognitive impairment. The association is largely attributable to visual impairment, while other mechanisms, associated with extraocular comorbidity and lifestyle, might partly explain this correlation. Available literature suggests that cataract surgery may be effective in decreasing fall risk, improving depressive symptoms and limiting the risk of cognitive impairment and dementia incidence, although intervention studies on these outcomes are still limited. In this review we also emphasize the need to move from the concept of visual acuity to functional vision, especially in the context of the geriatric patient. Research is needed regarding the effect on the cited outcomes of different cataract treatment strategies, such as systematic bilateral versus monolateral surgery and use of different intraocular lenses.

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AIMS: To evaluate clinical outcomes, functional vision and quality of life (QoL) after 35-year duration of type 1 diabetes (T1D) and proliferative diabetic retinopathy (PDR). METHODS: A population-based cohort study of T1D. Data from laboratory tests, ophthalmic examinations, multifunctional vision-test, and 15D-QoL measurements were analysed. RESULTS: 35 % of the original cohort (n = 216) had PDR, and 48 % of them were re-evaluated. They were 41 ± 3 [34-46] years old and 62 % were males. The duration of T1D was 35 ± 4 [29-41] years. 76 % had transdermal glucose monitoring. HbA1c had decreased from 80.1 mmol/mol to 63.6 mmol/mol (p < 0.001). Visual acuity was 73-77 ETDRS-letters. Two patients had visual impairment. Visual field sensitivities were lower in PDR vs. healthy controls (23.2 ± 3.9 dB vs. 26.9 ± 1.0 dB, and 14.9 ± 5.6 dB vs. 21.0 ± 2.0 dB, respectively, p < 0.001). Contrast sensitivity was similar, but the reaction time was longer in the PDR group (490.5 ms vs. 462.8 ms, p = 0.004). QoL-parameters concerning sleeping, usual activities, discomfort and symptoms, and sexual activity had decreased, but improved for mobility and distress. CONCLUSIONS: Long-term visual prognosis and QoL remained good despite the declined functional vision caused by PDR.

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An individual's functional vision may be measured via visual assessment and performance on mobility tasks. Since traditional mobility performance tests neglect to examine the effects of illumination on performance, the multi-luminance mobility test (MLMT) was designed to quantitatively assess the effects of illumination levels on an individual's mobility performance. In this chapter, we describe how the MLMT is conducted and scored in order to properly evaluate a participant's mobility under various light conditions.

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PURPOSE: Cortical visual impairment (CVI) is the common cause of pediatric visual impairment in cerebral palsy (CP) while exotropia is the most common strabismus associated with CP. We aim to observe the strabismic surgery outcomes in pediatric patients with CP and CVI. METHOD: Our medical records were collected from pediatric patients treated in our hospital from May 1, 2017 to Jan 1, 2022. With normal intelligence assessment and diagnosis of exotropia in children with CP and CVI, microsurgeries were performed under intravenous combined inhalation anesthesia. The strabismus was examined by the prism test under best vision correction and the contrast sensitivity testing (CST) was measured at five levels of spatial frequencies. RESULT: A total of 38 exotropia patients with CP and CVI were identified and included for analysis during the study period with age ranged from 5 to 12 years (mean 8.45 years) and mean follow up duration was 8.7 months (6-42 months). After bilateral lateral rectus recession (with/without medial rectus resection or inferior oblique transposition), the exotropia amount of participants were obviously revealed from - 30 ~ - 140 (median, IQR: - 50, 40) prism diopters (PD) preoperatively to 0 ~ - 15 (0, 5) PD postoperatively. Statistically significantly improvements were observed at all levels of spatial frequency on CST postoperatively, especially at high spatial frequency areas (p < 0.05). CONCLUSION: Our results demonstrated that the effect of strabismus surgery on exotropia in children with CP and CVI were stable and monocular contrast sensitivity post- operation increased significantly at all spatial frequencies levels.

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Cone cell-enriched macular degeneration is a major cause of functional vision deterioration. Astragaloside IV (Asg IV), an active triterpenoid saponin component with properties of anti-oxidative and anti-apoptotic damage, which benefit retinal tissue and capillaries. But, the nutraceutical therapeutic effects on functional vision have not been fully evaluated. In this study, mice were administrated to high-intensity light exposure after either receiving a vehicle or Asg IV (0.05, 0.5, and 50 mg/kg, BID). During this time, their spatial-visual performance, visual acuity (VA), and visual contrast sensitivity function (VCSF) were measured using the behavioral optomotor reflex method. Morphological changes in the retina were determined by histological examination. High energy light-evoked visual damage was confirmed by the loss in structural tissue integrity in the retina accompanied by a decline in both VA and VCSF, whereas the retina tissue exhibited loss of cone cell density and severe cone-specific opsin misplacement. In contrast, prophylactic oral Asg IV (0.5, and 50 mg/kg, BID)-treated exerted protective and improvement effects against light-evoked deterioration of functional vision. Asg IV treatment significantly improved the thresholds of VA and VCSF. In particular, Asg IV (50 mg/kg, BID) modulated and increased the survival of the photoreceptors, especially the cone cells, which targeted and enhanced the high spatial frequency-characterized VCSF. In contrast, the cellular protective effect of Asg IV (50 mg/kg, BID) on photoreceptors was significantly reversed by synchronous injection of a glucocorticoid receptor (GR) antagonist (mifepristone). This study demonstrated the major neuroretina-protective effect and functional vision-improving effect of Asg IV in vivo.

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