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Dementia and Geriatric Cognitive... 2023Visual and spatial perception (VSP) are cognitive domains frequently assessed in the screening and neuropsychological assessment of dementia. Evidence suggests that VSP...
INTRODUCTION
Visual and spatial perception (VSP) are cognitive domains frequently assessed in the screening and neuropsychological assessment of dementia. Evidence suggests that VSP impairment is common in the early stages of Alzheimer's disease (AD). Despite this evidence, the ability of VSP tests to discriminate between healthy older adults and people with AD remains mixed. The purpose of this literature review was to employ a systematic search strategy to identify empirical evidence supporting the diagnostic utility of VSP tests which may be used in the screening and diagnosis of AD.
METHODS
Specified criteria were used to perform a systematic literature search of the PsycINFO and PubMed databases with no date restrictions. Relevant data from the selected studies were extracted, and a published appraisal tool (the Quality Assessment of Diagnostic Accuracy Studies-2) was used to evaluate methodological quality.
RESULTS
Of the 144 articles returned, six studies and 11 VSP tests met review inclusion criteria. Four tests demonstrated both sensitivity and specificity values above 80%. A computerised 3D Visual Task demonstrated the highest sensitivity and specificity values (90% and 95%, respectively). The quality of the identified studies was considered to be satisfactory. Identified limitations and the implications of issues relating to study methodology are discussed, and recommendations for future research are suggested.
CONCLUSION
The evidence from this review suggests that certain tests of VSP may be a useful addition to the routine screening of AD.
Topics: Humans; Aged; Alzheimer Disease; Dementia; Cognitive Dysfunction; Neuropsychological Tests; Perception; Sensitivity and Specificity
PubMed: 37271132
DOI: 10.1159/000530911 -
Neuropsychology Review Dec 2023Although attention and early associative learning in preverbal children is predominantly driven by rapid eye-movements in response to moving visual stimuli and... (Meta-Analysis)
Meta-Analysis Review
Although attention and early associative learning in preverbal children is predominantly driven by rapid eye-movements in response to moving visual stimuli and sounds/words (e.g., associating the word "bottle" with the object), the literature examining the role of visual attention and memory in ongoing vocabulary development across childhood is limited. Thus, this systematic review and meta-analysis examined the association between visual memory and vocabulary development, including moderators such as age and task selection, in neurotypical children aged 2-to-12 years, from the brain-based perspective of cognitive neuroscience. Visual memory tasks were classified according to the visual characteristics of the stimuli and the neural networks known to preferentially process such information, including consideration of the distinction between the ventral visual stream (processing more static visuo-perceptual details, such as form or colour) and the more dynamic dorsal visual stream (processing spatial temporal action-driven information). Final classifications included spatio-temporal span tasks, visuo-perceptual or spatial concurrent array tasks, and executive judgment tasks. Visuo-perceptual concurrent array tasks, reliant on ventral stream processing, were moderately associated with vocabulary, while tasks measuring spatio-temporal spans, associated with dorsal stream processing, and executive judgment tasks (central executive), showed only weak correlations with vocabulary. These findings have important implications for health professionals and researchers interested in language, as they advocate for the development of more targeted language learning interventions that include specific and relevant aspects of visual processing and memory, such as ventral stream visuo-perceptual details (i.e., shape or colour).
Topics: Child; Humans; Vocabulary; Memory; Visual Perception; Brain; Language
PubMed: 36136174
DOI: 10.1007/s11065-022-09561-4 -
JMIR MHealth and UHealth Feb 2022Vision impairments (VIs) and blindness are major global public health issues. A visual acuity (VA) test is one of the most crucial standard psychophysical tests of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Vision impairments (VIs) and blindness are major global public health issues. A visual acuity (VA) test is one of the most crucial standard psychophysical tests of visual function and has been widely used in a broad range of health care domains, especially in many clinical settings. In recent years, there has been increasing research on mobile app-based VA assessment designed to allow people to test their VA at any time and any location.
OBJECTIVE
The goal of the review was to assess the accuracy and reliability of using mobile VA measurement apps.
METHODS
We searched PubMed, Embase, Cochrane Library, and Google Scholar for relevant articles on mobile apps for VA assessment published between January 1, 2008, and July 1, 2020. Two researchers independently inspected and selected relevant studies. Eventually, we included 22 studies that assessed tablet or smartphone apps for VA measurement. We then analyzed sensitivity, specificity, and accuracy in the 6 papers we found through a meta-analysis.
RESULTS
Most of the 22 selected studies can be considered of high quality based on the Quality Assessment of Diagnostic Accuracy Studies-2. In a meta-analysis of 6 studies involving 24,284 participants, we categorized the studies based on the age groups of the study participants (ie, aged 3-5 years, aged 6-22 years, and aged 55 years and older), examiner (ie, professional and nonprofessional examiners), and the type of mobile devices (ie, smartphone, iPad). In the group aged 3 to 5 years, the pooled sensitivity for VA app tests versus clinical VA tests was 0.87 (95% CI 0.79-0.93; P=.39), and the pooled specificity was 0.78 (95% CI 0.70-0.85; P=.37). In the group aged 6 to 22 years, the pooled sensitivity for VA app tests versus clinical VA tests was 0.86 (95% CI 0.84-0.87; P<.001), and the pooled specificity for VA app tests versus clinical VA tests was 0.91 (95% CI 0.90-0.91; P=.27). In the group aged 55 years and older, the pooled sensitivity for VA app tests versus clinical VA tests was 0.85 (95% CI 0.55-0.98), and the pooled specificity for VA app tests versus clinical VA tests was 0.98 (95% CI 0.95-0.99). We found that the nonprofessional examiner group (AUC 0.93) had higher accuracy than the professional examiner group (AUC 0.87). In the iPad-based group, the pooled sensitivity for VA app tests versus clinical VA tests was 0.86, and the pooled specificity was 0.79. In the smartphone-based group, the pooled sensitivity for VA app tests versus clinical VA tests was 0.86 (P<.001), and the pooled specificity for VA app tests versus clinical VA tests was 0.91 (P<.001).
CONCLUSIONS
In this study, we conducted a comprehensive review of the research on existing mobile apps for VA tests to investigate their diagnostic value and limitations. Evidence gained from this study suggests that mobile app-based VA tests can be useful for on-demand VI detection.
Topics: Adolescent; Adult; Child; Child, Preschool; Computers, Handheld; Humans; Middle Aged; Mobile Applications; Reproducibility of Results; Smartphone; Visual Acuity; Young Adult
PubMed: 35156935
DOI: 10.2196/26275 -
Documenta Ophthalmologica. Advances in... Feb 2021Visual evoked potentials (VEPs) can be used to measure visual resolution via a spatial frequency (SF) limit as an objective estimate of visual acuity. The aim of this... (Review)
Review
PURPOSE
Visual evoked potentials (VEPs) can be used to measure visual resolution via a spatial frequency (SF) limit as an objective estimate of visual acuity. The aim of this systematic review is to collate descriptions of the VEP SF limit in humans, healthy and disordered, and to assess how accurately and precisely VEP SF limits reflect visual acuity.
METHODS
The protocol methodology followed the PRISMA statement. Multiple databases were searched using "VEP" and "acuity" and associated terms, plus hand search: titles, abstracts or full text were reviewed for eligibility. Data extracted included VEP SF limits, stimulus protocols, VEP recording and analysis techniques and correspondence with behavioural acuity for normally sighted healthy adults, typically developing infants and children, healthy adults with artificially degraded vision and patients with ophthalmic or neurological conditions.
RESULTS
A total of 155 studies are included. Commonly used stimulus, recording and analysis techniques are summarised. Average healthy adult VEP SF limits vary from 15 to 40 cpd, depend on stimulus, recording and analysis techniques and are often, but not always, poorer than behavioural acuity measured either psychophysically with an identical stimulus or with a clinical acuity test. The difference between VEP SF limit and behavioural acuity is variable and strongly dependent on the VEP stimulus and choice of acuity test. VEP SF limits mature rapidly, from 1.5 to 9 cpd by the end of the first month of life to 12-20 cpd by 8-12 months, with slower improvement to 20-40 cpd by 3-5 years. VEP SF limits are much better than behavioural thresholds in the youngest, typically developing infants. This difference lessens with age and reaches equivalence between 1 and 2 years; from around 3-5 years, behavioural acuity is better than the VEP SF limit, as for adults. Healthy, artificially blurred adults had slightly better behavioural acuity than VEP SF limits across a wide range of acuities, while adults with heterogeneous ophthalmic or neurological pathologies causing reduced acuity showed a much wider and less consistent relationship. For refractive error, ocular media opacity or pathology primarily affecting the retina, VEP SF limits and behavioural acuity had a fairly consistent relationship across a wide range of acuity. This relationship was much less consistent or close for primarily macular, optic nerve or neurological conditions such as amblyopia. VEP SF limits were almost always normal in patients with non-organic visual acuity loss.
CONCLUSIONS
The VEP SF limit has great utility as an objective acuity estimator, especially in pre-verbal children or patients of any age with motor or learning impairments which prevent reliable measurement of behavioural acuity. Its diagnostic power depends heavily on adequate, age-stratified, reference data, age-stratified empirical calibration with behavioural acuity, and interpretation in the light of other electrophysiological and clinical findings. Future developments could encompass faster, more objective and robust techniques such as real-time, adaptive control.
REGISTRATION
International prospective register of systematic reviews PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ ), registration number CRD42018085666.
Topics: Adult; Amblyopia; Child; Child, Preschool; Electroretinography; Evoked Potentials, Visual; Humans; Infant; Vision, Ocular; Visual Acuity
PubMed: 32488810
DOI: 10.1007/s10633-020-09770-3 -
Consciousness and Cognition Mar 2023Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a... (Review)
Review
BACKGROUND
Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a dimly lit room. The illusory effects range from mild alterations in colour, or contrast, to the perception of distorted facial features, or new strange faces.The current review critically evaluates studies investigating strange face illusions, their methodological quality, and existing interpretations.
METHOD
Searches conducted using Scopus, PubMed, ScienceDirect and the grey literature until June 2022 identified 21 studies (N = 1,132; healthy participants n = 1,042; clinical participants n = 90) meeting the inclusion criteria (i.e., providing new empirical evidence relating to strange face illusions). The total sample had a mean age of 28.3 years (SD = 10.31) and two thirds (67 %) of participants tested to date are female. Results are reported using the Preferred Reporting Items for Systematic Reviews and meta-Analyses (PRISMA) guidelines. The review was preregistered at the Open Science Framework (OSF: https://osf.io/ek48d).
RESULTS
Pooling data across studies, illusory new strange faces are experienced by 58% (95%CI 48 to 68) of nonclinical participants. Study quality as assessed by the Appraisal Tool for Cross-Sectional Studies (AXIS) revealed that 3/21 (14.28%) studies were rated as high, 9/21 (42.86%) as moderate and 9/21 (42.86%) as low quality. Whilst the items relating specifically to reporting quality scored quite highly, those relating to study design and possible biases were lower and more variable. Overall, study quality accounted for 87% of the variance in reporting rates for strange faces, with higher quality being associated with lower illusion rates. The prevalence of illusions was also significantly greater in samples that were older, had higher proportions of female participants and for the interpersonal dyad (IGDT) compared to the mirror gaze paradigm (MGT). The moderating impact of study quality persisted in a multiple meta-regression involving participant age, paradigm type (IGDT vs MGT) and level of feature distortion. Our review point to the importance of reduced light levels, face stimuli and prolonged eye fixation for strange face illusions to emerge.
CONCLUSION
Strange face illusions reliably occur in both mirror-gazing and interpersonal gazing dyad paradigms. Further research of higher quality is required to establish the prevalence and particularly, the mechanisms underpinning strange face illusions.
Topics: Humans; Female; Adult; Male; Illusions; Cross-Sectional Studies; Face; Fixation, Ocular; Dissociative Disorders
PubMed: 36764163
DOI: 10.1016/j.concog.2023.103480 -
International Ophthalmology Jun 2024This meta-analysis reviews the evidence for the risks and benefits associated with orthokeratology (OK) treatment compared with other methods of myopia control in... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
This meta-analysis reviews the evidence for the risks and benefits associated with orthokeratology (OK) treatment compared with other methods of myopia control in children and adults.
METHODS
A systematic search of Cochrane Central Register of Controlled Trials, Pubmed, Embase and Ovid was conducted from database inception to 22nd August 2021. Studies that reported on risks, visual and ocular biometric effects of OK in patients > 5 years of age with myopia (- 0.75 to - 6.00D) were included. Main outcomes are change in axial length and any adverse event.
RESULTS
Fourty-five papers were included in this systematic review and meta-analysis. The quality of data was variable and of moderate certainty, and selection bias likely skewed the results towards a relative benefit for OK. The rate of axial elongation in children was lower for OK treatment compared to other treatment modalities at one year (MD - 0.16 mm, 95% CI - 0.25 to - 0.07). Rate of change in axial length in children rebounded after OK discontinuation compared to participants who continued treatment (MD 0.10 mm, 95% CI 0.06 to 0.14). Adults and children wearing OK were up to 3.79 times more likely to experience an adverse event when compared with conventional contact lenses (OR 3.79, 95% CI 1.24 to ll.), though this evidence base is underdeveloped and requires additional well-designed studies for substantial conclusions to be drawn.
CONCLUSIONS
OK arrests myopia progression while in use, however, there remain unanswered questions about the optimal duration of treatment, discontinuation effects and long-term risk for adverse events.
Topics: Humans; Orthokeratologic Procedures; Myopia; Refraction, Ocular; Visual Acuity; Axial Length, Eye; Contact Lenses; Child; Risk Assessment
PubMed: 38904856
DOI: 10.1007/s10792-024-03175-w -
Neurological Sciences : Official... Apr 2022Hemianopia is a complete or partial blindness in the visual fields of both eyes, commonly caused by cerebral infarction. It has been hypothesized that systematic... (Review)
Review
BACKGROUND
Hemianopia is a complete or partial blindness in the visual fields of both eyes, commonly caused by cerebral infarction. It has been hypothesized that systematic audio-visual (AV) stimulation of the blind hemifield can improve accuracy and search times, probably due to the stimulation of bimodal representations in the superior colliculus (SC), an important multisensory structure involved in both the initiation and execution of saccades.
METHODS
A narrative synthesis of the findings is presented to highlight how AV rehabilitation impacts on patients with hemianopia including visual oculomotor function, functional ability in activities of daily living, hemianopic dyslexia, visual scanning and searching tasks, maintaining of functional ability post training and the effect on brain multisensory integration by using neuroimaging.
RESULTS
Sixteen studies were included (fourteen articles (188 participants) and two literature reviews). Results were grouped into AV training of hemianopia in adults and in children and then further grouped according to the AV task type: tasks measuring the training effects by comparing visual stimulation training to audio-visual training, localization abilities in homonymous hemianopia (HH) and AV integration in patients with HH.
CONCLUSION
Systematic AV training may improve the processing of visual information by recruiting subcortical pathways, and because most of the patients with visual cortex damage have an intact SC, it might be useful to use the bimodal AV training to activate retinotectal functions. Nevertheless, the underlying mechanisms supporting the reported positive effects are not currently understood. Systematic functional and/or structural imaging studies may help in understanding the underlying mechanism and inform the design of optimal training paradigms.
Topics: Acoustic Stimulation; Activities of Daily Living; Adult; Child; Hemianopsia; Humans; Photic Stimulation; Stroke; Survivors; Visual Fields
PubMed: 35149925
DOI: 10.1007/s10072-022-05926-y -
Autism Research : Official Journal of... Aug 2022Autism spectrum disorder (ASD) is characterized by significant social functioning impairments, including (but not limited to) emotion recognition, mentalizing, and joint... (Meta-Analysis)
Meta-Analysis Review
Autism spectrum disorder (ASD) is characterized by significant social functioning impairments, including (but not limited to) emotion recognition, mentalizing, and joint attention. Despite extensive investigation into the correlates of social functioning in ASD, only recently has there been focus on the role of low-level sensory input, particularly visual processing. Extensive gaze deficits have been described in ASD, from basic saccadic function through to social attention and the processing of complex biological motion. Given that social functioning often relies on accurately processing visual information, inefficient visual processing may contribute to the emergence and sustainment of social functioning difficulties in ASD. To explore the association between measures of gaze and social functioning in ASD, a systematic review and meta-analysis was conducted. A total of 95 studies were identified from a search of CINAHL Plus, Embase, OVID Medline, and psycINFO databases in July 2021. Findings support associations between increased gaze to the face/head and eye regions with improved social functioning and reduced autism symptom severity. However, gaze allocation to the mouth appears dependent on social and emotional content of scenes and the cognitive profile of participants. This review supports the investigation of gaze variables as potential biomarkers of ASD, although future longitudinal studies are required to investigate the developmental progression of this relationship and to explore the influence of heterogeneity in ASD clinical characteristics. LAY SUMMARY: This review explored how eye gaze (e.g., where a person looks when watching a movie) is associated with social functioning in autism spectrum disorder (ASD). We found evidence that better social functioning in ASD was associated with increased eye gaze toward faces/head and eye regions. Individual characteristics (e.g., intelligence) and the complexity of the social scene also influenced eye gaze. Future research including large longitudinal studies and studies investigating the influence of differing presentations of ASD are recommended.
Topics: Attention; Autism Spectrum Disorder; Fixation, Ocular; Humans; Social Interaction; Visual Perception
PubMed: 35593039
DOI: 10.1002/aur.2729 -
Graefe's Archive For Clinical and... Oct 2020Intravitreal injection of VEGF inhibitors has become the standard of care for different macular diseases within the last years resulting in improved visual outcomes.... (Review)
Review
PURPOSE
Intravitreal injection of VEGF inhibitors has become the standard of care for different macular diseases within the last years resulting in improved visual outcomes. Under real-life conditions, however, the necessity for frequent retreatments and reexaminations poses a burden for patients and treatment centers. Non-adherence and non-persistence to intravitreal treatment may lead to inferior clinical outcomes, and knowledge of contributing factors is crucial to improve adherence. This systematic review analyzes current literature for potential factors involved in non-adherence and non-persistence.
METHODS
A systematic search was conducted in PubMed and Embase including three different aspects of intravitreal injection therapy: (1) diseases with intravitreal injections as treatment, (2) intravitreal injection, and (3) aspects of therapy adherence or therapy persistence. Data from identified quantitative studies were further extracted and grouped according to WHO criteria (condition, socio-economy, therapy, patient, and health system). The methodological quality of identified studies was graded. Identified qualitative studies (i.e., interviews) were descriptively analyzed and their findings narratively reported.
RESULTS
Twenty-four publications were included. In 16 of those publications, a quantitative data analysis was conducted, analyzing factors associated with non-adherence. Worse visual acuity at baseline and unfavorable development of visual acuity, higher age, and greater distance to the treatment center were associated with non-adherence, while there was inconsistent evidence for an association of comorbidity. In qualitative studies, high follow-up/treatment burden, fear and anxiety, disappointed patient expectations, and lack of motivation to continue treatment were reported as reasons for non-persistence.
CONCLUSIONS
Knowledge of potential barriers in IVT treatment may improve adherence and potentially clinical results. Improvements can be achieved particularly in the healthcare complex (organizational improvements) and the "patient" complex by establishing realistic expectations. Recurrent education of the patient may be necessary.
Topics: Angiogenesis Inhibitors; Humans; Intravitreal Injections; Ranibizumab; Vascular Endothelial Growth Factor A; Visual Acuity
PubMed: 32572607
DOI: 10.1007/s00417-020-04798-2 -
The Cochrane Database of Systematic... Sep 2022Ocular surface burns can be caused by chemicals (alkalis and acids) or direct heat. One effect of the burn is damage to the limbal epithelial stem cells of the ocular... (Review)
Review
BACKGROUND
Ocular surface burns can be caused by chemicals (alkalis and acids) or direct heat. One effect of the burn is damage to the limbal epithelial stem cells of the ocular surface with delayed re-epithelialisation, stem cell failure, and conjunctivalisation of the cornea. Amniotic membrane transplantation (AMT) performed in the acute phase (day 0 to day 7) following an ocular surface burn is claimed to reduce pain and accelerate healing. The surgery involves securing a layer of amniotic membrane (AM) to the eyelid margins as a patch to cover the entire ocular surface. However, there is debate about the severity of an ocular burn that may benefit from AMT and uncertainty of whether AMT improves outcomes.
OBJECTIVES
To compare the effect of AMT with medical therapy in the first seven days after an ocular surface burn, compared to medical therapy alone.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2021, Issue 9); Ovid MEDLINE; Ovid Embase; LILACS; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 29 September 2021.
SELECTION CRITERIA
We included randomised trials that compared an AMT applied in the first seven days following an ocular surface burn in addition to medical therapy with medical therapy alone. The outcome measures were failure of re-epithelialisation by day 21 post injury, visual acuity at final follow-up, corneal neovascularisation, symblepharon, time to re-epithelialisation and adverse effects.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened search results, assessed the included studies for risk of bias and extracted relevant data. We contacted trial investigators for missing information. We summarised data using risk ratios (RRs) and mean differences (MDs) as appropriate.
MAIN RESULTS
We analysed two RCTs, but excluded individual patients who had been treated outside the acute phase in one of the studies (data provided by study authors). In total, 36 moderate burns from one RCT and 92 severe burns from two RCTs were evaluated separately. For both categories, the certainty of the evidence was downgraded principally as a result of high risks of performance and detection biases, and because of imprecision indicated by very wide confidence intervals. In addition, follow-up was insufficiently frequent to calculate time-to-epithelialisation precisely. Moderate severity ocular burns (Roper-Hall classification II-III) The relative risk of AMT on failure of epithelialisation by day 21 was 0.18 (0.02 to 1.31), and LogMAR visual acuity was 0.32 lower (0.55 to 0.09 lower) in the treatment group (i.e. better), suggesting a possible benefit of AMT. The GRADE assessment for failure of epithelialisation by day 21 was downgraded to very low due to the risk of bias and imprecision (very wide confidence intervals including no effect). The GRADE assessment for visual acuity at final follow-up was downgraded to low due to the risk of bias and imprecision (optimal information size not met). The relative effects of AMT on corneal neovascularisation (RR 0.56; 0.21 to 1.48), symblepharon (RR 0.41; 0.02 to 9.48) and time-to-epithelialisation (13 days lower; 26.30 lower to 0.30 higher) suggest possible benefit of AMT, but the wide confidence intervals indicate that both harm and benefit are possible. GRADE assessments for these outcomes were once again downgraded to very low due to the risk of bias and imprecision. Since adverse effects are rare, the small sample would have fewer occurrences of rare but potentially important adverse effects. The GRADE assessment for adverse effects was therefore considered to be low. Severe ocular burns (Roper-Hall classification IV) The relative risk of AMT on failure of epithelialisation by day 21 was 1.03 (0.94 to 1.12), and LogMAR visual acuity was 0.01 higher (0.29 lower to 0.31 higher) in the treatment group (i.e, worse), indicating no benefit of AMT. GRADE assessments for failure of epithelialisation by day 21 and final outcomes were downgraded to low. The relative effects of AMT on corneal neovascularisation (RR 0.84; 0.66 to 1.06), symblepharon (RR 0.89; 0.56 to 1.42) and time-to-epithelialisation (1.66 days lower; 11.09 lower to 7.77 higher) may include both benefit and harm. GRADE assessments for corneal neovascularisation, symblepharon and time-to-epithelialisation were downgraded to low due to risk of bias and imprecision. For adverse effects, the GRADE assessment was downgraded to low, reflecting the small sample sizes in the RCTs.
AUTHORS' CONCLUSIONS
There is uncertain evidence to support the treatment of moderate acute ocular surface burns with AMT in addition to standard medical therapy as a means of preventing failure of epithelialisation by day 21, improving visual outcome and reducing corneal neovascularisation, symblepharon formation and time-to-epithelialisation. For severe burns, the available evidence does not indicate any significant benefit of treatment with AMT.
Topics: Amnion; Corneal Neovascularization; Eye Burns; Humans; Visual Acuity; Wound Healing
PubMed: 36047788
DOI: 10.1002/14651858.CD009379.pub3