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Journal of Cataract and Refractive... May 2024To compare flange depth for a modified scleral pocket (SP) vs no scleral pocket (NSP) technique (Yamane technique) for intrascleral intraocular lens (IOL) fixation. (Randomized Controlled Trial)
Randomized Controlled Trial Observational Study Comparative Study
PURPOSE
To compare flange depth for a modified scleral pocket (SP) vs no scleral pocket (NSP) technique (Yamane technique) for intrascleral intraocular lens (IOL) fixation.
SETTING
Instituto de Oftalmología Santa Fe, Santa Fe, Argentina.
DESIGN
Prospective, randomized, single-surgeon, observational study.
METHODS
Eyes with aphakia and no capsular support were included. They were divided into 2 groups: one was programmed for a double-needle flanged intrascleral IOL fixation as originally described by Shin Yamane with NSP and the second group had a modified SP technique. Flange depth was measured with anterior-segment optical coherence tomography (AS-OCT) at 1 month, 3 months, 6 months, and 12 months postoperatively, and the results were compared.
RESULTS
Each group comprised 18 eyes of 18 patients, giving a total of 36 flanges per group. The groups were comparable preoperatively. At 12 months, uncorrected distance visual acuity and corrected distance visual acuity (CDVA) were not statistically different for both groups (P = .333; P = .448). Spherical equivalent (SEQ) was not significantly different between groups at 12 months postoperatively (P = .078). AS-OCT revealed a significantly deeper flange position for the SP group at 1 month, 3 months, 6 months, and 12 months postoperatively (P < .05).
CONCLUSIONS
When performing a double-needle intrascleral IOL fixation in aphakic eyes with no capsular support, a modified scleral pocket technique provides a significantly deeper flange position with no difference in CDVA or SEQ 12 months postoperatively.
Topics: Humans; Sclera; Lens Implantation, Intraocular; Prospective Studies; Visual Acuity; Tomography, Optical Coherence; Lenses, Intraocular; Female; Male; Middle Aged; Aged; Aphakia, Postcataract; Surgical Flaps; Suture Techniques; Pseudophakia; Refraction, Ocular
PubMed: 38651698
DOI: 10.1097/j.jcrs.0000000000001383 -
Eye and Brain 2024This review delineates the ocular motor disturbances across a spectrum of neurodegenerative disorders, including Alzheimer's Disease (AD) and related disorders (ADRD),... (Review)
Review
This review delineates the ocular motor disturbances across a spectrum of neurodegenerative disorders, including Alzheimer's Disease (AD) and related disorders (ADRD), Parkinson's Disease (PD), atypical parkinsonism, and others, leveraging advancements in eye-tracking technology for enhanced diagnostic precision. We delve into the different classes of eye movements, their clinical assessment, and specific abnormalities manifesting in these diseases, highlighting the nuanced differences and shared patterns. For instance, AD and ADRD are characterized by increased saccadic latencies and instability in fixation, while PD features saccadic hypometria and mild smooth pursuit impairments. Atypical parkinsonism, notably Progressive Supranuclear Palsy (PSP) and Corticobasal Syndrome (CBS), presents with distinct ocular motor signatures such as vertical supranuclear gaze palsy and saccadic apraxia, respectively. Our review underscores the diagnostic value of eye movement analysis in differentiating between these disorders and also posits the existence of underlying common pathological mechanisms. We discuss how eye movements have potential as biomarkers for neurodegenerative diseases but also some of the existing limitations.
PubMed: 38617403
DOI: 10.2147/EB.S384769 -
Digital Biomarkers 2024Visual acuity and image stability are crucial for daily activities, particularly during head motion. The vestibulo-ocular reflex (VOR) and its suppression (VORS) support... (Review)
Review
BACKGROUND
Visual acuity and image stability are crucial for daily activities, particularly during head motion. The vestibulo-ocular reflex (VOR) and its suppression (VORS) support stable fixation of objects of interest. The VOR drives a reflexive eye movement to counter retinal slip of a stable target during head motion. In contrast, VORS inhibits this countermovement when the target stimulus is in motion. The VORS allows for object fixation when it aligns with the direction of the head's movement, or when an object within or outside the peripheral vision needs to be focused upon.
SUMMARY
Deficits of the VORS have been linked to age-related diseases such as balance deficits associated with an increased fall risk. Therefore, the accurate assessment of the VORS is of particular clinical relevance. However, current clinical assessment methods for VORS are mainly qualitative and not sufficiently standardised. Recent advances in digital health technology, such as smartphone-based videooculography, offer a promising alternative for assessing VORS in a more accessible, efficient, and quantitative manner. Moreover, integrating mobile eye-tracking technology with virtual reality environments allows for the implementation of controlled VORS assessments with different visual inputs. These assessment approaches allow the extraction of novel parameters with potential pathomechanistic and clinical relevance.
KEY MESSAGES
We argue that researchers and clinicians can obtain a more nuanced understanding of this ocular stabilisation reflex and its associated pathologies by harnessing digital health technology for VORS assessment. Further research is warranted to explore the technologies' full potential and utility in clinical practice.
PubMed: 38617128
DOI: 10.1159/000537842 -
Physiology & Behavior Jun 2024Children born very preterm often exhibit atypical gaze behaviors, affect recognition difficulties and are at risk for cerebral white matter damage. This study explored...
Children born very preterm often exhibit atypical gaze behaviors, affect recognition difficulties and are at risk for cerebral white matter damage. This study explored links between these sequalae. In 24 12-year-old children born very preterm, ventricle size using Evans and posterior ventricle indices, and corpus callosum area were used to measure white matter thickness. The findings revealed a correlation between less attention towards the eyes and larger ventricle size. Ventricle and posterior corpus callosum sizes were correlated to affect-recognition proficiency. Findings suggest a link between white matter damage, gaze behavior, and affect recognition accuracy, emphasizing a relation with social perception.
Topics: Humans; Pilot Projects; Magnetic Resonance Imaging; Female; Child; Male; Infant, Extremely Premature; White Matter; Recognition, Psychology; Corpus Callosum; Cerebral Ventricles; Fixation, Ocular
PubMed: 38615730
DOI: 10.1016/j.physbeh.2024.114553 -
Neuropsychologia Jul 2024Left smooth pursuit eye movement training in response to large-field visual motion (optokinetic stimulation) has become a promising rehabilitation method in left spatial...
Left smooth pursuit eye movement training in response to large-field visual motion (optokinetic stimulation) has become a promising rehabilitation method in left spatial inattention or neglect. The mechanisms underlying the therapeutic effect, however, remain unknown. During optokinetic stimulation, there is an error in visual localisation ahead of the line of sight. This could indicate a change in the brain's estimate of one's own direction of gaze. We hypothesized that optokinetic stimulation changes the brain's estimate of gaze. Because this estimate is critical for coding the locus of attention in the visual space relative to the body and across sensory modalities, its change might underlie the change in spatial attention. Here, we report that in healthy participants optokinetic stimulation causes not only a directional bias in the proprioceptive signal from the extraocular muscles, but also a corresponding shift of the locus of attention. Both changes outlasted the period of stimulation. This result forms a step in investigating a causal link between the adaptation in the sensorimotor gaze signals and the recovery in spatial neglect.
Topics: Humans; Attention; Male; Perceptual Disorders; Female; Adult; Fixation, Ocular; Photic Stimulation; Space Perception; Young Adult; Motion Perception; Proprioception; Pursuit, Smooth
PubMed: 38599567
DOI: 10.1016/j.neuropsychologia.2024.108883 -
Attention, Perception & Psychophysics May 2024Competing theories attempt to explain what guides eye movements when exploring natural scenes: bottom-up image salience and top-down semantic salience. In one study, we...
Competing theories attempt to explain what guides eye movements when exploring natural scenes: bottom-up image salience and top-down semantic salience. In one study, we apply language-based analyses to quantify the well-known observation that task influences gaze in natural scenes. Subjects viewed ten scenes as if they were performing one of two tasks. We found that the semantic similarity between the task and the labels of objects in the scenes captured the task-dependence of gaze (t(39) = 13.083; p < 0.001). In another study, we examined whether image salience or semantic salience better predicts gaze during a search task, and if viewing strategies are affected by searching for targets of high or low semantic relevance to the scene. Subjects searched 100 scenes for a high- or low-relevance object. We found that image salience becomes a worse predictor of gaze across successive fixations, while semantic salience remains a consistent predictor (X(1, N=40) = 75.148, p < .001). Furthermore, we found that semantic salience decreased as object relevance decreased (t(39) = 2.304; p = .027). These results suggest that semantic salience is a useful predictor of gaze during task-related scene viewing, and that even in target-absent trials, gaze is modulated by the relevance of a search target to the scene in which it might be located.
Topics: Humans; Semantics; Fixation, Ocular; Attention; Male; Female; Young Adult; Adult; Pattern Recognition, Visual; Eye Movements
PubMed: 38594445
DOI: 10.3758/s13414-024-02883-w -
Scientific Reports Apr 2024Altered nonverbal communication patterns especially with regard to gaze interactions are commonly reported for persons with autism spectrum disorder (ASD). In this study...
Impaired recognition of interactive intentions in adults with autism spectrum disorder not attributable to differences in visual attention or coordination via eye contact and joint attention.
Altered nonverbal communication patterns especially with regard to gaze interactions are commonly reported for persons with autism spectrum disorder (ASD). In this study we investigate and differentiate for the first time the interplay of attention allocation, the establishment of shared focus (eye contact and joint attention) and the recognition of intentions in gaze interactions in adults with ASD compared to control persons. Participants interacted via gaze with a virtual character (VC), who they believed was controlled by another person. Participants were instructed to ascertain whether their partner was trying to interact with them. In fact, the VC was fully algorithm-controlled and showed either interactive or non-interactive gaze behavior. Participants with ASD were specifically impaired in ascertaining whether their partner was trying to interact with them or not as compared to participants without ASD whereas neither the allocation of attention nor the ability to establish a shared focus were affected. Thus, perception and production of gaze cues seem preserved while the evaluation of gaze cues appeared to be impaired. An additional exploratory analysis suggests that especially the interpretation of contingencies between the interactants' actions are altered in ASD and should be investigated more closely.
Topics: Adult; Humans; Autism Spectrum Disorder; Intention; Fixation, Ocular; Social Perception; Nonverbal Communication
PubMed: 38594289
DOI: 10.1038/s41598-024-58696-2 -
Scientific Reports Apr 2024Eye contact is a central component in face-to-face interactions. It is important in structuring communicative exchanges and offers critical insights into others'...
Eye contact is a central component in face-to-face interactions. It is important in structuring communicative exchanges and offers critical insights into others' interests and intentions. To better understand eye contact in face-to-face interactions, we applied a novel, non-intrusive deep-learning-based dual-camera system and investigated associations between eye contact and autistic traits as well as self-reported eye contact discomfort during a referential communication task, where participants and the experimenter had to guess, in turn, a word known by the other individual. Corroborating previous research, we found that participants' eye gaze and mutual eye contact were inversely related to autistic traits. In addition, our findings revealed different behaviors depending on the role in the dyad: listening and guessing were associated with increased eye contact compared with describing words. In the listening and guessing condition, only a subgroup who reported eye contact discomfort had a lower amount of eye gaze and eye contact. When describing words, higher autistic traits were associated with reduced eye gaze and eye contact. Our data indicate that eye contact is inversely associated with autistic traits when describing words, and that eye gaze is modulated by the communicative role in a conversation.
Topics: Humans; Autistic Disorder; Communication; Nonverbal Communication; Fixation, Ocular; Intention
PubMed: 38589489
DOI: 10.1038/s41598-024-58701-8 -
Scientific Reports Apr 2024Previous work has shown divergent pupil dilation (PD) and gaze behavior in individuals with autism spectrum disorder (ASD), which may relate to the development of social...
Previous work has shown divergent pupil dilation (PD) and gaze behavior in individuals with autism spectrum disorder (ASD), which may relate to the development of social difficulties in early life. Here, we investigated temporal dynamics of both phenotypes during naturalistic videos of a person displaying facial emotion expressions in 61 autistic and 61 non-autistic preschoolers. PD was segmented into three serial time components derived from a principal component analysis. Growth curve analysis was applied to analyze changes in looking time on eye and mouth regions over time. Groups did not differ in PD time components. Growth curve analysis revealed initially shorter looking times on the eyes and longer looking times on the mouth in autistic versus non-autistic preschoolers. However, a reversion of this pattern was observed over time, suggesting a delayed compensatory increase in eye attention during prolonged viewing periods in autistic children. Positive and negative associations of PD components and gaze behavior over time indicated a dynamic temporal relationship during emotion viewing. Our findings emphasize the need to apply time-sensitive measures in ecologically valid research, which may index etiological mechanisms of social difficulties in ASD.
Topics: Child; Humans; Autism Spectrum Disorder; Pupil; Autistic Disorder; Emotions; Attention; Fixation, Ocular
PubMed: 38570565
DOI: 10.1038/s41598-024-58480-2 -
BMJ Open Ophthalmology Apr 2024Pterygium is a common ocular surface disorder that requires surgical intervention for treatment. Conjunctival autografts are preferred over simple excision due to lower... (Meta-Analysis)
Meta-Analysis
Modified sutureless and glue-free method versus conventional sutures for conjunctival autograft fixation in primary pterygium surgery: a systematic review and meta-analysis.
BACKGROUND
Pterygium is a common ocular surface disorder that requires surgical intervention for treatment. Conjunctival autografts are preferred over simple excision due to lower recurrence rates. This systematic review and meta-analysis compared the modified sutureless glue-free (MSGF) method with conventional sutures (CS) for conjunctival autograft fixation in primary pterygium surgery.
METHODS
A comprehensive search was conducted in MEDLINE, Embase, CENTRAL, Google Scholar and ClinicalTrials.gov for randomised controlled trials (RCTs) comparing MSGF and CS conjunctival autografts. Outcome measures included operation time, recurrence and postoperative complications. Standardised mean difference (SMD) and risk ratio (RR) were used for continuous and dichotomous outcomes, respectively.
RESULTS
11 RCTs involving 833 participants were included. The analysis revealed that MSGF had a significantly shorter operation time compared with CS (SMD -3.704, 95% CI -5.122 to -2.287, p<0.001). CS was associated with a higher risk of foreign body sensation (RR 0.22, 95% CI 0.06 to 0.74, p=0.01). MSGF was associated with a higher risk of graft dehiscence (RR 9.01, 95% CI 2.74 to 29.68, p=0.000) and graft retraction (RR 2.37, 95% CI 1.17 to 4.77, p=0.02). No significant differences were found in recurrence, graft haemorrhage, granuloma, Dellen and conjunctival oedema.
CONCLUSION
Using the MSGF technique in conjunctival autograft fixation for pterygium surgery reduces operation time by relying solely on the patient's blood for fixation. However, it increases the risk of graft dehiscence and retraction. However, CS is linked to a higher likelihood of experiencing foreign body sensations. Understanding the learning curve and surgeon familiarity with novel techniques is crucial for optimising patient care and surgical outcomes, while individualised decision-making is necessary considering the advantages and disadvantages of each approach. Further research is warranted to minimise complications and optimise surgical outcomes.
Topics: Humans; Pterygium; Autografts; Fibrin Tissue Adhesive; Recurrence; Conjunctiva; Sutures; Foreign Bodies
PubMed: 38565231
DOI: 10.1136/bmjophth-2023-001621