Clinical and Experimental Optometry最新文献

Clinical relevance: Vision plays an important role in the normal motor development of children. Increased understanding of this relationship is important for providing appropriate advice in a clinical setting.

Background: Growing evidence indicates that vision anomalies are associated with reduced motor performance in children. This study investigated whether feedback loop noise, induced by common vision anomalies, adversely affects sensorimotor processing in children aged 7 to 16.

Methods: Sensorimotor function was measured in 409 children aged 7-8, 10-11, and 15-16 years as part of an annual school vision programme. The vision programme included assessment of visual acuity, binocular vision and refraction. Aiming and steering sensorimotor performance were measured using a validated tool that utilised a stylus on a tablet computer. Analysis of covariance models tested whether visual function (binocular near visual acuity, amplitude of accommodation, near point of convergence) and refractive error, along with age, contributed to the variance in aiming and steering performance.

Results: Sensorimotor performance showed considerable variation within each age group. The simplest models that captured aiming variance included age and refractive error (R² = 0.42, F[3, 402] = 99.04, p < 0.001), whilst age and accommodative function contributed towards steering variance (R² = 0.22, F[3, 400] = 38.72, p < 0.001).

Conclusion: Hyperopic refractive errors and reduced accommodative function affect the ability to perform sensorimotor transformations, negatively impacting age-expected manual control skill levels. Longitudinal research is needed to test whether correcting hyperopia can: (i) improve the development of sensorimotor processing; (ii) produce beneficial changes in motor skill abilities.

Clinical relevance: Convergence insufficiency is a common binocular vision anomaly among college students, and its impact on routine near work activities of students needs to be assessed.

Background: This study assessed the reading, writing, and typing speed of young college students with convergence insufficiency and age-matched controls.

Methods: A case-control study was conducted among 50 students with convergence insufficiency and 50 control students aged 18 to 25 years. All subjects underwent visual examinations including refractive assessments and evaluations of accommodative and binocular vision parameters. Reading and writing speeds were assessed using the International Reading Speed Texts (IReST) charts while typing speed was measured using the Psychology Experiment Building Language (PEBL) software. Reading, writing and typing speeds were compared between the two groups; and their correlation with clinical parameters related to convergence insufficiency was examined. Additionally, speeds were compared among symptomatic and asymptomatic students, assessed using the Convergence Insufficiency Symptomatic Survey (CISS) scale.

Results: The mean ± standard deviation age of the participants was 20.72 ± 2.00 years. The two groups did not differ in age, gender distribution, visual acuity or spherical equivalent (p > .05 for all). The median [interquartile range] reading speed was 160.34 [152.32-172.00] words per minute (WPM) in convergence insufficiency students, and 183.52 [168.34-201.36] WPM in control students (p < .001). Writing speed averaged 32.98 ± 4.31 WPM in convergence insufficiency students versus 36.48 ± 4.23 WPM in controls (p < .001). The median typing speed was 19.57 [17.57-24.73] WPM in convergence insufficiency students, and 24.15 [19.31-27.40] WPM in control students (p = .007). Correlation analysis showed none to poor correlations between speeds and clinical parameters. No significant differences were observed in speeds between symptomatic and asymptomatic students with convergence insufficiency.

Conclusion: College students with convergence insufficiency were found to have reduced reading, writing and typing speeds.

Clinical relevance: Systemic sclerosis can affect vision quality by causing fibrosis in the cornea and lens, as in all organs.

Background: The aim of this work is to evaluate corneal and lens densitometry alongside anterior segment parameters in patients with systemic sclerosis (SSc), and to assess whether subclinical structural changes are detectable using Scheimpflug-based imaging.

Methods: This prospective case-control study included 20 patients with SSc and 20 age- and sex-matched healthy controls. All participants underwent comprehensive ophthalmologic examination, including anterior segment imaging using the Pentacam HR system. Corneal and lens densitometry values were recorded in concentric zones and evaluated in the anterior, central, and posterior layers. Additional parameters such as central corneal thickness (CCT), anterior chamber (AC) depth, AC angle, and corneal volume were also assessed.

Results: No statistically significant differences were observed in anterior segment parameters (CCT, AC depth, AC angle, corneal volume) or lens densitometry values between SSc patients and controls (p > 0.05). However, significantly reduced corneal densitometry values were found in the anterior and central layers of the 0-2 mm and 2-6 mm zones in the SSc group (p < 0.05). No significant differences were noted in the posterior corneal layer across all zones.

Conclusion: Although anterior segment and lens parameters appeared unaffected, reduced corneal densitometry in the central optical zone suggests subtle stromal remodelling in patients with long-standing SSc. These microstructural changes may reflect chronic fibrotic remodelling and warrant further investigation.

Clinical relevance: Blinking plays a vital role in protecting the eye and maintaining ocular surface health. Understanding blink behaviour may help identify ocular surface disorders and detect blink abnormalities associated with systemic or neurological conditions.

Background: This study assessed the kinematic characteristics of spontaneous blinking versus mechanically evoked reflex blinking and explored their relationship with potentially related ocular surface characteristics.

Methods: This pilot study used high-speed infrared imaging to capture spontaneous and reflex blinking in 11 participants. A five-minute video recording of spontaneous blinking was captured while participants watched a wildlife documentary. Reflex blinking was evoked by delivering a puff of air into the right eye at random intervals. Blink velocity, completeness and duration were determined using custom semi-automated analysis software. Corneal sensitivity, subbasal corneal nerve morphology, non-invasive tear break-up time and tear meniscus height were also assessed.

Results: Spontaneous blinking was less complete than reflex blinking (p = 0.012). Closing-phase velocity was greater for reflex blinking than for spontaneous blinking (p < 0.001), whilst no significant difference was observed for opening-phase velocity (p = 0.164). Closed-phase duration was longer for reflex blinking than for spontaneous blinking (p = 0.023), whereas total blink duration did not differ significantly (p = 0.718). Exploratory analyses suggested potential associations between tear film parameters and blink dynamics.

Conclusion: Differences were found in the kinematic characteristics of spontaneous and reflex blinking. Preliminary associations between blink characteristics and ocular surface parameters warrant confirmation in larger studies. High-speed infrared imaging is a promising technique that may be used in the future to better understand how blinking is affected by ocular, systemic and neurological conditions.

Clinical relevance: A non-refractive approach for potential myopia management is introduced as spectacle films with opaque features, hypothesised to modulate retinal ganglion cell activity away from the baseline state of the eye. Visual performance of these spectacle films is currently unknown.

Background: The aim of this work is to compare the visual performance of spectacle films with opaque non-refractive features (test), MiYOSMART (control: MS), and single vision (control: SV) lenses.

Methods: This was a prospective, randomised, unmasked, cross-over study where 37 myopic adults (18-42 years) wore each lens for a minimum of 5 days. Subjective visual performance was assessed with a 1-10 numeric rating scale for clarity of vision, vision at night, vision when walking, and overall vision satisfaction and visual acuity (monocular at 6 m and binocular at 6 m and 40 cm). Willingness-to-purchase, based on vision and myopia efficacy, was assessed with a binary Yes/No response.

Results: Test and SV were rated higher than MS (p ≤ 0.005) for all subjective ratings, while SV was rated higher than test (p ≤ 0.02) for all ratings except vision when walking (p = 0.11). A higher proportion were willing to purchase both test and SV compared to MS based on vision (p ≤ 0.001), with no difference between test and SV (p = 0.20). A higher proportion were willing to purchase SV compared to MS based on myopia efficacy (p = 0.005), with no difference between test and either control (p > 0.06). SV was significantly better than MS for acuity at 40 cm (p = 0.004) with no differences between lenses for other acuity measurements (p > 0.1).

Conclusions: Test offered better subjective visual performance than MS with higher proportions of participants willing to purchase based on vision. Test offered worse subjective visual performance than SV with no differences in willingness-to-purchase questions. SV offered better visual performance than MS and higher proportions of participants willing to purchase for vision or myopia management.

Clinical relevance: Optometrists play a key role in the provision of diabetic eye care. Timely and accurate diagnosis and management of the ocular complications of diabetes mellitus can ensure optimal patient outcomes and minimise vision loss.

Background: Diabetes mellitus is a global public health concern. Diabetic retinopathy is a complication of diabetes mellitus and the leading cause of vision impairment globally, particularly in low- and middle-income countries. Despite optometrists playing a critical role in diabetic eye care, their clinical practices remain underreported in South Africa. The objective of this study was to determine practice patterns of South African optometrists towards diabetic eye care.

Methods: In this cross-sectional study conducted in South Africa, a validated online questionnaire was distributed to optometrists to explore their self-reported practice patterns towards diabetic eye care.

Results: The sample comprised 254 participants. Most participants were confidence in grading (62.2%) and managing (74.8%) diabetic retinopathy while some were confident in detecting (45.7%) and managing (47.3%) diabetic macular oedema. The majority of participants had fundus cameras (90%) but only 25.2% had optical coherence tomography devices and of these 85% found them useful for diabetic macular oedema detection. Many participants (54%) used classification systems and guidelines for diabetic retinopathy with a significant association between routine use of these tools and confidence level (p = 0.02). Approximately 52% felt that current clinical guidelines should be reviewed and revised.

Conclusion: There exists a need for greater access to optical coherence tomography, standardised national guidelines, and diabetic focused clinical training in South Africa. This will enhance diagnostic confidence, streamline referrals and reduce vision loss associated with diabetic eye disease.

Clinical relevance: Clear, evidence-based guidelines support optometrists in diagnosing and managing age-related macular degeneration, a leading cause of vision loss in older adults. This condition is an increasing focus of clinical care due to expanding treatment options and evolving imaging technologies.

Background: Clinical practice guidelines support consistent, evidence-based care in optometry and play a critical role in guiding the diagnosis and management of chronic eye diseases. This paper discusses the methodological approach used to develop age-related macular degeneration guidelines, emphasising the modified Delphi approach used to refine and formally establish recommendations.

Methods: Recommendations were developed from a literature review and draft guideline. An expert working group of optometrists (n = 9) participated in a three-round Delphi process, rating their agreement with the draft recommendations using a 6-point Likert scale across two survey rounds, followed by a virtual meeting to discuss and re-vote on unclear or contentious items. Quantitative and qualitative measures during the first two rounds of the Delphi survey guided recommendation refinement and inclusion for discussion in round 3. Consensus for inclusion was defined as a mean score ≥5 and ≥80% agreement.

Results: Out of 37 initial recommendations, 25 (68%) were accepted and included in the final guideline. Consensus was achieved for recommendations concerning clinical classification, assessment and management strategies. Round 3 discussions helped resolve uncertainties and refine recommendations wording, particularly regarding nutritional supplements and clinical biomarkers for progression. Adoption of the Delphi approach demonstrated the value of both quantitative and qualitative feedback.

Conclusion: The feasibility and value of using a modified Delphi method to develop optometric clinical practice guidelines is demonstrated. The process supported the inclusion or exclusion of recommendations in a systematic way with the final guideline offering contemporary, practice-relevant guidance for the diagnosis and management of age-related macular degeneration.