1
|
Dai B, Cham KM, Abel LA. Visual search in infantile nystagmus syndrome. Clin Exp Optom 2024; 107:641-648. [PMID: 37848183 DOI: 10.1080/08164622.2023.2260805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/04/2023] [Accepted: 09/14/2023] [Indexed: 10/19/2023] Open
Abstract
CLINICAL RELEVANCE Research on infantile nystagmus syndrome (INS) and visual search is limited. Conducting this research could assist practitioners in understanding how INS affects the real-life visual activities of patients and aid in developing new clinical visual function assessments for INS. BACKGROUND The aim of this work is to investigate how subjects with INS perform visual search tasks, and, particularly, to assess how INS subjects perform when targets are located at their null position or away from it, and when under additional cognitive demands. METHODS INS subjects (N = 15) and controls (N = 20) performed conjunction and feature search tasks, both with and without mental arithmetic. Search performance was assessed using log-transformed total search time, gaze-dependent search time, and accuracy. Cognitive demand was quantified by pupil size and the NASA task-load index score. RESULTS INS subjects showed longer search times compared to controls in conjunction search (P < 0.01), but not in feature search. Within INS and control subjects, the total search times were significantly increased by the addition of mental arithmetic (P < 0.0001). There was no difference in gaze-dependent search times between null target position and 15° away from null target position of subjects in conjunction search (P > 0.05). Accuracies were 100% for both control and INS subjects in both conjunction and feature search. CONCLUSION Conjunction visual search was impaired in adult INS subjects, and further worsened under increased cognitive demand. The null position did not affect the visual search performance in INS.
Collapse
Affiliation(s)
- Bing Dai
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Kwang Meng Cham
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Larry Allen Abel
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
- Optometry, School of Medicine, Deakin University, Victoria, Australia
| |
Collapse
|
2
|
Almagren B, Dunn MJ. Measurement of visual function in infantile nystagmus: a systematic review. Br J Ophthalmol 2024; 108:1038-1043. [PMID: 38164583 DOI: 10.1136/bjo-2023-324254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 10/30/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND/AIMS Recent work has called into question the ability of visual acuity (VA) to accurately represent changes in visual function in infantile nystagmus (IN). This systematic review investigated factors affecting visual performance in IN, to guide development of suitable alternatives to VA. METHODS Included studies used an experimental manipulation to assess changes in visual function in people with IN. Interventional studies, case series and case studies were excluded. Six databases were searched in August 2023. Selection, detection, attrition and measurement bias were assessed. Due to heterogeneous methodologies, narrative synthesis was undertaken. RESULTS Eighteen relevant papers were identified, 11 of which complied with the review criteria. Articles were grouped according to the factor manipulated to evoke within-participant changes in performance (motion blur, psychological state, gaze angle or visual crowding). Optotype, image, grating and moving stimuli have been employed under varying lighting conditions and exposure duration. CONCLUSION Several factors affecting visual performance should be considered when assessing visual function in IN. While maximum VA is a useful metric, its measurement deliberately minimises nystagmus-specific factors such as changes in visual performance with gaze angle and the 'slow to see' phenomenon. Maximum VA can be measured using the null zone, providing unlimited viewing time, reducing stress/mental load and minimising visual crowding. Gaze-dependent functional vision space is a promising measure which quantifies the impact of the null zone but does not consider temporal vision. Although no complete measurement technique has yet been proven, this review provides insights to guide future work towards development of appropriate methods.
Collapse
Affiliation(s)
- Bader Almagren
- Optometry Department, King Saud University, Riyadh, Saudi Arabia
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Matt J Dunn
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| |
Collapse
|
3
|
Chin BM, Wang M, Mikkelsen LT, Friedman CT, Ng CJ, Chu MA, Cooper EA. A paradigm for characterizing motion misperception in people with typical vision and low vision. Optom Vis Sci 2024; 101:252-262. [PMID: 38857038 DOI: 10.1097/opx.0000000000002139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024] Open
Abstract
PURPOSE We aimed to develop a paradigm that can efficiently characterize motion percepts in people with low vision and compare their responses with well-known misperceptions made by people with typical vision when targets are hard to see. METHODS We recruited a small cohort of individuals with reduced acuity and contrast sensitivity (n = 5) as well as a comparison cohort with typical vision (n = 5) to complete a psychophysical study. Study participants were asked to judge the motion direction of a tilted rhombus that was either high or low contrast. In a series of trials, the rhombus oscillated vertically, horizontally, or diagonally. Participants indicated the perceived motion direction using a number wheel with 12 possible directions, and statistical tests were used to examine response biases. RESULTS All participants with typical vision showed systematic misperceptions well predicted by a Bayesian inference model. Specifically, their perception of vertical or horizontal motion was biased toward directions orthogonal to the long axis of the rhombus. They had larger biases for hard-to-see (low contrast) stimuli. Two participants with low vision had a similar bias, but with no difference between high- and low-contrast stimuli. The other participants with low vision were unbiased in their percepts or biased in the opposite direction. CONCLUSIONS Our results suggest that some people with low vision may misperceive motion in a systematic way similar to people with typical vision. However, we observed large individual differences. Future work will aim to uncover reasons for such differences and identify aspects of vision that predict susceptibility.
Collapse
Affiliation(s)
- Benjamin M Chin
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, California
| | - Minqi Wang
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, California
| | - Loganne T Mikkelsen
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, California
| | - Clara T Friedman
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, California
| | - Cherlyn J Ng
- Department of Cognitive Sciences, The University of California, Irvine, Irvine, California
| | - Marlena A Chu
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, California
| | | |
Collapse
|
4
|
Morelli F, Catalano G, Scognamillo I, Balzarotti N, Luparia A, Olivier L, Bertone C, Gori M, Signorini S. Visual Function and Neuropsychological Profiling of Idiopathic Infantile Nystagmus. Brain Sci 2023; 13:1348. [PMID: 37759948 PMCID: PMC10526276 DOI: 10.3390/brainsci13091348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Though considered a benign condition, idiopathic infantile nystagmus (IIN) may be associated with decreased visual acuity and oculo-motor abnormalities, resulting in developmental delays and poor academic performance. Nevertheless, the specific visual function profile of IIN and its possible impact on neuropsychological development have been poorly investigated. To fill this gap, we retrospectively collected the clinical data of 60 children presenting with IIN over a 10-year period (43 male; mean age of 7 years, range of 2 months-17 years, 9 months). The majority of the subjects in our cohort presented with reduced visual acuity for far distances and normal visual acuity for near distances, associated with oculo-motor abnormalities. The overall scores of cognitive and visual-cognitive tests were in the normal range, but revealed peculiar cognitive and visual-cognitive profiles, defined by specific frailties in processing speed and visual-motor integration. The same neuropsychological profiles characterize many neurodevelopmental disorders and may express a transnosographic vulnerability of the dorsal stream. As the first study to explore the neuropsychologic competencies in children with IIN, our study unveils the presence of subclinical frailties that need to be addressed to sustain academic and social inclusion.
Collapse
Affiliation(s)
- Federica Morelli
- Department of Brain and Behavioral Sciences, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy; (F.M.); (I.S.)
- Developmental Neuro-Ophthalmology Unit, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (A.L.); (L.O.); (S.S.)
| | - Guido Catalano
- Department of Brain and Behavioral Sciences, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy; (F.M.); (I.S.)
| | - Ilaria Scognamillo
- Department of Brain and Behavioral Sciences, University of Pavia, Via Agostino Bassi 21, 27100 Pavia, Italy; (F.M.); (I.S.)
| | - Nicolò Balzarotti
- Unit for Visually Impaired People, Istituto Italiano di Tecnologia, Via Enrico Melen 82, 16100 Genova, Italy; (N.B.); (M.G.)
| | - Antonella Luparia
- Developmental Neuro-Ophthalmology Unit, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (A.L.); (L.O.); (S.S.)
| | - Lucrezia Olivier
- Developmental Neuro-Ophthalmology Unit, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (A.L.); (L.O.); (S.S.)
| | - Chiara Bertone
- Department of Surgical and Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, IRCCS Fondazione Policlinico San Matteo, University of Pavia, 27100 Pavia, Italy;
| | - Monica Gori
- Unit for Visually Impaired People, Istituto Italiano di Tecnologia, Via Enrico Melen 82, 16100 Genova, Italy; (N.B.); (M.G.)
| | - Sabrina Signorini
- Developmental Neuro-Ophthalmology Unit, IRCCS Mondino Foundation, Via Mondino 2, 27100 Pavia, Italy; (A.L.); (L.O.); (S.S.)
| |
Collapse
|
5
|
Xu J, Chen Y, Chen H, Wang J, Yan T, Yu X, Ye L, Xu M, Xu S, Yu H, Deng R, Zheng Y, Yang Y, Chen Q, Yu X, Liu Y, Liang Y, Gu F. Best-corrected visual acuity results facilitate molecular diagnosis of infantile nystagmus patients harboring FRMD7 mutations. Exp Eye Res 2023:109567. [PMID: 37423457 DOI: 10.1016/j.exer.2023.109567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 05/25/2023] [Accepted: 07/05/2023] [Indexed: 07/11/2023]
Abstract
The visual function of patients with infantile nystagmus (IN) can be significantly decreased owing to constant eye movement. While, reaching a definitive diagnosis becomes a challenge due to genetic heterozygous of this disease. To address it, we investigated whether best-corrected visual acuity (BCVA) results can facilitate the molecular diagnosis of IN patients harboring FRMD7 mutations. 200 patients with IN from 55 families and 133 sporadic cases were enrolled. Mutations were comprehensively screened by direct sequencing using gene-specific primers for FRMD7. We also retrieved related literature to verify the results based on our data. We found that the BCVA of patients with IN harboring FRMD7 mutations was between 0.5 and 0.7, which was confirmed by data retrieved from the literature. Our results showed that BCVA results facilitate the molecular diagnosis of patients with IN harboring FRMD7 mutations. In addition, we identified 31 FRMD7 mutations from the patients, including six novel mutations, namely, frameshift mutation c.1492_1493insT (p.Y498LfsTer14), splice-site mutation c.353C > G, three missense mutations [c.208C > G (p.P70A), c.234G > A (p.M78I), and c.1109G > A (p.H370R)], and nonsense mutation c.1195G > T (p.E399Ter). This study demonstrates that BCVA results may facilitate the molecular diagnosis of IN patients harboring FRMD7 mutations.
Collapse
Affiliation(s)
- Jinling Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yamin Chen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Haoran Chen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Jiahua Wang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Tong Yan
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Xudong Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Liang Ye
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Meiping Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Suzhong Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Huanyun Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Ruzhi Deng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yihan Zheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yeqin Yang
- School of Nursing, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiang Chen
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Xinping Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yong Liu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yuanbo Liang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China.
| | - Feng Gu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China; The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Hunan Normal University School of Medicine, Changsha, China.
| |
Collapse
|
6
|
Dai B, Cham KM, Abel LA. Perception of Coherent Motion in Infantile Nystagmus Syndrome. Invest Ophthalmol Vis Sci 2022; 63:31. [PMID: 35072688 PMCID: PMC8802013 DOI: 10.1167/iovs.63.1.31] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Purpose Research on infantile nystagmus syndrome (INS) and motion perception is limited. We investigated how individuals with INS perform coherent motion tasks. Particularly, we assessed how the null position affects their performance. Methods Subjects with INS and controls identified the direction of coherent motion stimuli (22 subjects with INS and 13 controls) in a two-alternative forced-choice design. For subjects with INS, testing was done at the null position and 15 degrees away from it. If there was no null, testing was done at primary gaze position and 15 degrees away from primary. For controls, testing was done at primary gaze position and 20 degrees away from primary. Horizontal and vertical motion coherence thresholds were determined. Results Subjects with INS showed significantly higher horizontal and vertical motion coherence thresholds compared with controls at both gaze positions (P < 0.001). Within the INS group, for 12 subjects with INS who had an identified null position, no differences in coherence thresholds were found between their null and 15 degrees away from it (P > 0.05). Conclusions Coherent motion perception was impaired in subjects with INS. The null position did not significantly influence motion coherence thresholds for either horizontal or vertical motion.
Collapse
Affiliation(s)
- Bing Dai
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Kwang Meng Cham
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia
| | - Larry Allen Abel
- Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia.,Optometry, School of Medicine, Deakin University, Waurn Ponds, Australia
| |
Collapse
|