LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 60

Search options

  1. Article ; Online: New insights in presbyopia: impact of correction strategies.

    Wolffsohn, James S / Davies, Leon N / Sheppard, Amy L

    BMJ open ophthalmology

    2023  Volume 8, Issue 1

    Abstract: Presbyopia occurs when the physiologically normal age-related reduction in the eyes focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements. ... ...

    Abstract Presbyopia occurs when the physiologically normal age-related reduction in the eyes focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements. Hence, it is more about the impact it has on an individual's visual ability to function in their environment to maintain their lifestyle than a measured loss of focusing ability. Presbyopia has a significant impact on an individual's quality of life and emotional state. While a range of amelioration strategies exist, they are often difficult to access in the developing world and prescribing is generally not optimal even in developed countries. This review identified the need for a standardised definition of presbyopia to be adopted. An appropriate battery of tests should be applied in evaluating presbyopic management options and the results of clinical trials should be published (even if unsuccessful) to accelerate the provision of better outcomes for presbyopes.
    MeSH term(s) Humans ; Presbyopia/diagnosis ; Quality of Life ; Eye ; Electric Power Supplies
    Language English
    Publishing date 2023-06-06
    Publishing country England
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ISSN 2397-3269
    ISSN (online) 2397-3269
    DOI 10.1136/bmjophth-2022-001122
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Article ; Online: Effect of peripheral defocus on axial growth and modulation of refractive error in children with anisohyperopia.

    Beasley, Ian G / Davies, Leon N / Logan, Nicola S

    Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)

    2023  Volume 43, Issue 4, Page(s) 805–814

    Abstract: Purpose: To establish whether axial growth and refractive error can be modulated in anisohyperopic children by imposing relative peripheral hyperopic defocus (RPHD) using multifocal soft contact lenses.: Methods: This study is a prospective, ... ...

    Abstract Purpose: To establish whether axial growth and refractive error can be modulated in anisohyperopic children by imposing relative peripheral hyperopic defocus (RPHD) using multifocal soft contact lenses.
    Methods: This study is a prospective, controlled paired-eye study with anisohyperopic children. Axial growth and refractive error were observed without intervention for the first 6 months of the 3-year trial with participants wearing single vision spectacles. Then, participants wore a centre-near, multifocal, soft contact lens (+2.00 D add) in their more hyperopic eye for 2 years, with a single vision contact lens worn in the fellow eye if required. The 'centre-near' portion of the contact lens in the more hyperopic eye corrected distance refractive error while the 'distance' portion imposed hyperopic defocus in the peripheral retina. Participants reverted to single vision spectacles for the final 6 months.
    Results: Eleven participants, mean age of 10.56 years (SD 1.43; range 8.25-13.42), completed the trial. No increase in axial length (AL) was found during the first 6 months in either eye (p > 0.99). Axial growth across the 2-year intervention period was 0.11 mm (SEM 0.03; p = 0.06) in the test eye versus 0.15 mm (SEM 0.03; p = 0.003) in the control eye. AL was invariant during the final 6 months in both eyes (p > 0.99). Refractive error was stable during the first 6 months in both eyes (p = 0.71). Refractive error change across the 2-year intervention period was -0.23 D (SEM 0.14; p = 0.32) in the test eye versus -0.30 D (SEM 0.14; p = 0.61) in the control eye. Neither eye demonstrated a change in refractive error during the final 6 months (p > 0.99).
    Conclusions: Imposing RPHD using the centre-near, multifocal, contact lens specified here did not accelerate axial growth nor reduce refractive error in anisohyperopic children.
    MeSH term(s) Child ; Humans ; Contact Lenses, Hydrophilic ; Eye ; Hyperopia/therapy ; Myopia/therapy ; Prospective Studies ; Refraction, Ocular ; Refractive Errors/therapy ; Retina
    Language English
    Publishing date 2023-04-07
    Publishing country England
    Document type Controlled Clinical Trial ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 604564-9
    ISSN 1475-1313 ; 0275-5408
    ISSN (online) 1475-1313
    ISSN 0275-5408
    DOI 10.1111/opo.13139
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 1700: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  3. Article ; Online: Utility of artificial intelligence-based large language models in ophthalmic care.

    Biswas, Sayantan / Davies, Leon N / Sheppard, Amy L / Logan, Nicola S / Wolffsohn, James S

    Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)

    2024  Volume 44, Issue 3, Page(s) 641–671

    Abstract: Purpose: With the introduction of ChatGPT, artificial intelligence (AI)-based large language models (LLMs) are rapidly becoming popular within the scientific community. They use natural language processing to generate human-like responses to queries. ... ...

    Abstract Purpose: With the introduction of ChatGPT, artificial intelligence (AI)-based large language models (LLMs) are rapidly becoming popular within the scientific community. They use natural language processing to generate human-like responses to queries. However, the application of LLMs and comparison of the abilities among different LLMs with their human counterparts in ophthalmic care remain under-reported.
    Recent findings: Hitherto, studies in eye care have demonstrated the utility of ChatGPT in generating patient information, clinical diagnosis and passing ophthalmology question-based examinations, among others. LLMs' performance (median accuracy, %) is influenced by factors such as the iteration, prompts utilised and the domain. Human expert (86%) demonstrated the highest proficiency in disease diagnosis, while ChatGPT-4 outperformed others in ophthalmology examinations (75.9%), symptom triaging (98%) and providing information and answering questions (84.6%). LLMs exhibited superior performance in general ophthalmology but reduced accuracy in ophthalmic subspecialties. Although AI-based LLMs like ChatGPT are deemed more efficient than their human counterparts, these AIs are constrained by their nonspecific and outdated training, no access to current knowledge, generation of plausible-sounding 'fake' responses or hallucinations, inability to process images, lack of critical literature analysis and ethical and copyright issues. A comprehensive evaluation of recently published studies is crucial to deepen understanding of LLMs and the potential of these AI-based LLMs.
    Summary: Ophthalmic care professionals should undertake a conservative approach when using AI, as human judgement remains essential for clinical decision-making and monitoring the accuracy of information. This review identified the ophthalmic applications and potential usages which need further exploration. With the advancement of LLMs, setting standards for benchmarking and promoting best practices is crucial. Potential clinical deployment requires the evaluation of these LLMs to move away from artificial settings, delve into clinical trials and determine their usefulness in the real world.
    MeSH term(s) Humans ; Artificial Intelligence ; Clinical Decision-Making ; Eye ; Judgment ; Ophthalmology
    Language English
    Publishing date 2024-02-25
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 604564-9
    ISSN 1475-1313 ; 0275-5408
    ISSN (online) 1475-1313
    ISSN 0275-5408
    DOI 10.1111/opo.13284
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 1700: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  4. Article ; Online: The effect of peripheral defocus on axial growth and modulation of refractive error in hyperopes.

    Beasley, Ian G / Davies, Leon N / Logan, Nicola S

    Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)

    2022  Volume 42, Issue 3, Page(s) 534–544

    Abstract: Purpose: To establish whether axial growth and refractive error can be modulated in hyperopic children by imposing relative peripheral hyperopic defocus using multifocal soft contact lenses.: Methods: A prospective controlled study with hyperopic ... ...

    Abstract Purpose: To establish whether axial growth and refractive error can be modulated in hyperopic children by imposing relative peripheral hyperopic defocus using multifocal soft contact lenses.
    Methods: A prospective controlled study with hyperopic participants allocated to a control or test group. Control group participants were corrected with single vision spectacles and changes to axial length and refractive error were followed for 3 years. For the test group, axial growth and post-cycloplegic refractive error were observed with participants wearing single vision spectacles for the first 6 months of the trial and then corrected with centre-near multifocal soft contact lenses with a 2.00 D add for 2 years. The central 'near' portion of the contact lens corrected distance refractive error while the 'distance' portion imposed hyperopic defocus. Participants reverted to single vision spectacles for the final 6 months of the study.
    Results: Twenty-two participants, mean age 11.13 years (SD 1.72) (range 8.33-13.92), completed the trial. Axial length did not change during the first 6 months in either group (p = 1.00). Axial growth across the 2-year intervention period was 0.17 mm (SEM 0.04) (p < 0.0005) in the test group versus 0.06 mm (SEM 0.07) (p = 0.68) in the control group. Axial length was invariant during the final 6 months in either group (p = 1.00). Refractive error was stable during the first 6 months in both groups (p = 1.00). Refractive error change across the 2-year intervention period was -0.26 D (SEM 0.14) (p = 0.38) in the test group versus -0.01 D (SEM 0.09) (p = 1.00) in the control group. Neither the test (p = 1.00) nor control (p = 0.63) group demonstrated a change in refractive error during the final 6 months.
    Conclusions: The rate of axial growth can be accelerated in children with hyperopia using centre-near multifocal soft contact lenses.
    MeSH term(s) Child ; Contact Lenses, Hydrophilic ; Humans ; Hyperopia/therapy ; Myopia/therapy ; Prospective Studies ; Refraction, Ocular ; Refractive Errors/therapy
    Language English
    Publishing date 2022-02-21
    Publishing country England
    Document type Controlled Clinical Trial ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 604564-9
    ISSN 1475-1313 ; 0275-5408
    ISSN (online) 1475-1313
    ISSN 0275-5408
    DOI 10.1111/opo.12951
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 1700: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  5. Article ; Online: Assessing the utility of ChatGPT as an artificial intelligence-based large language model for information to answer questions on myopia.

    Biswas, Sayantan / Logan, Nicola S / Davies, Leon N / Sheppard, Amy L / Wolffsohn, James S

    Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)

    2023  Volume 43, Issue 6, Page(s) 1562–1570

    Abstract: Purpose: ChatGPT is an artificial intelligence language model, which uses natural language processing to simulate human conversation. It has seen a wide range of applications including healthcare education, research and clinical practice. This study ... ...

    Abstract Purpose: ChatGPT is an artificial intelligence language model, which uses natural language processing to simulate human conversation. It has seen a wide range of applications including healthcare education, research and clinical practice. This study evaluated the accuracy of ChatGPT in providing accurate and quality information to answer questions on myopia.
    Methods: A series of 11 questions (nine categories of general summary, cause, symptom, onset, prevention, complication, natural history, treatment and prognosis) were generated for this cross-sectional study. Each question was entered five times into fresh ChatGPT sessions (free from influence of prior questions). The responses were evaluated by a five-member team of optometry teaching and research staff. The evaluators individually rated the accuracy and quality of responses on a Likert scale, where a higher score indicated greater quality of information (1: very poor; 2: poor; 3: acceptable; 4: good; 5: very good). Median scores for each question were estimated and compared between evaluators. Agreement between the five evaluators and the reliability statistics of the questions were estimated.
    Results: Of the 11 questions on myopia, ChatGPT provided good quality information (median scores: 4.0) for 10 questions and acceptable responses (median scores: 3.0) for one question. Out of 275 responses in total, 66 (24%) were rated very good, 134 (49%) were rated good, whereas 60 (22%) were rated acceptable, 10 (3.6%) were rated poor and 5 (1.8%) were rated very poor. Cronbach's α of 0.807 indicated good level of agreement between test items. Evaluators' ratings demonstrated 'slight agreement' (Fleiss's κ, 0.005) with a significant difference in scoring among the evaluators (Kruskal-Wallis test, p < 0.001).
    Conclusion: Overall, ChatGPT generated good quality information to answer questions on myopia. Although ChatGPT shows great potential in rapidly providing information on myopia, the presence of inaccurate responses demonstrates that further evaluation and awareness concerning its limitations are crucial to avoid potential misinterpretation.
    Language English
    Publishing date 2023-07-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 604564-9
    ISSN 1475-1313 ; 0275-5408
    ISSN (online) 1475-1313
    ISSN 0275-5408
    DOI 10.1111/opo.13207
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 1700: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  6. Article ; Online: Authors' Reply: Assessing the utility of ChatGPT as an artificial intelligence-based large language model for information to answer questions on myopia.

    Biswas, Sayantan / Logan, Nicola S / Davies, Leon N / Sheppard, Amy L / Wolffsohn, James S

    Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)

    2023  Volume 44, Issue 1, Page(s) 233–234

    Language English
    Publishing date 2023-08-27
    Publishing country England
    Document type Letter
    ZDB-ID 604564-9
    ISSN 1475-1313 ; 0275-5408
    ISSN (online) 1475-1313
    ISSN 0275-5408
    DOI 10.1111/opo.13227
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 1700: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  7. Article ; Online: BCLA CLEAR Presbyopia: Definitions.

    Wolffsohn, James S / Naroo, Shehzad A / Bullimore, Mark A / Craig, Jennifer P / Davies, Leon N / Markoulli, Maria / Schnider, Cristina / Morgan, Philip B

    Contact lens & anterior eye : the journal of the British Contact Lens Association

    2024  , Page(s) 102155

    Abstract: Presbyopia is often the first sign of ageing experienced by humans. Standardising terminology and adopting it across the BCLA CLEAR Presbyopia reports, improves consistency in the communication of the evidence-based understanding of this universal ... ...

    Abstract Presbyopia is often the first sign of ageing experienced by humans. Standardising terminology and adopting it across the BCLA CLEAR Presbyopia reports, improves consistency in the communication of the evidence-based understanding of this universal physiological process. Presbyopia can be functionally and psychologically debilitating, especially for those with poor access to eyecare. Presbyopia was defined as occurring when the physiologically normal age-related reduction in the eye's focusing range reaches a point that, when optimally corrected for far vision, the clarity of vision at near is insufficient to satisfy an individual's requirements. Accommodation is the change in optical power of the eye due to a change in crystalline lens shape and position, whereas pseudo-accommodation is the attainment of functional near vision in an emmetropic or far-corrected eye without changing the refractive power of the eye. Other definitions specific to vision and lenses for presbyopia were also defined. It is recommended that these definitions be consistently adopted in order to standardise future research, clinical evaluations and education.
    Language English
    Publishing date 2024-04-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 2004847-6
    ISSN 1476-5411 ; 1367-0484
    ISSN (online) 1476-5411
    ISSN 1367-0484
    DOI 10.1016/j.clae.2024.102155
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  8. Article ; Online: Presbyopia: Effectiveness of correction strategies.

    Wolffsohn, James S / Davies, Leon N

    Progress in retinal and eye research

    2018  Volume 68, Page(s) 124–143

    Abstract: Presbyopia is a global problem affecting over a billion people worldwide. The prevalence of unmanaged presbyopia is as high as 50% of those over 50 years of age in developing world populations, due to a lack of awareness and accessibility to affordable ... ...

    Abstract Presbyopia is a global problem affecting over a billion people worldwide. The prevalence of unmanaged presbyopia is as high as 50% of those over 50 years of age in developing world populations, due to a lack of awareness and accessibility to affordable treatment, and is even as high as 34% in developed countries. Definitions of presbyopia are inconsistent and varied, so we propose a redefinition that states "presbyopia occurs when the physiologically normal age-related reduction in the eye's focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements". Strategies for correcting presbyopia include separate optical devices located in front of the visual system (reading glasses) or a change in the direction of gaze to view through optical zones of different optical powers (bifocal, trifocal or progressive addition spectacle lenses), monovision (with contact lenses, intraocular lenses, laser refractive surgery and corneal collagen shrinkage), simultaneous images (with contact lenses, intraocular lenses and corneal inlays), pinhole depth of focus expansion (with intraocular lenses, corneal inlays and pharmaceuticals), crystalline lens softening (with lasers or pharmaceuticals) or restored dynamics (with 'accommodating' intraocular lenses, scleral expansion techniques and ciliary muscle electrostimulation); these strategies may be applied differently to the two eyes to optimise the range of clear focus for an individual's task requirements and minimise adverse visual effects. However, none fully overcome presbyopia in all patients. While the restoration of natural accommodation or an equivalent remains elusive, guidance is given on presbyopic correction evaluation techniques.
    MeSH term(s) Accommodation, Ocular/physiology ; Aging/physiology ; Ciliary Body/physiology ; Contact Lenses ; Eyeglasses ; Humans ; Laser Therapy ; Lens, Crystalline/physiology ; Lenses, Intraocular ; Presbyopia/physiopathology ; Presbyopia/therapy ; Refractive Surgical Procedures ; Visual Acuity/physiology
    Language English
    Publishing date 2018-09-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 1182683-6
    ISSN 1873-1635 ; 1350-9462
    ISSN (online) 1873-1635
    ISSN 1350-9462
    DOI 10.1016/j.preteyeres.2018.09.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Se 824: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  9. Article ; Online: Ciliary Muscle Dimension Changes With Accommodation Vary in Myopia and Emmetropia.

    Kaphle, Dinesh / Schmid, Katrina L / Davies, Leon N / Suheimat, Marwan / Atchison, David A

    Investigative ophthalmology & visual science

    2022  Volume 63, Issue 6, Page(s) 24

    Abstract: Purpose: The purpose of this study was to determine whether accommodation-induced changes in ciliary muscle dimensions vary between emmetropes and myopes, and the effect of the image analysis method.: Methods: Seventy adults aged 18 to 27 years ... ...

    Abstract Purpose: The purpose of this study was to determine whether accommodation-induced changes in ciliary muscle dimensions vary between emmetropes and myopes, and the effect of the image analysis method.
    Methods: Seventy adults aged 18 to 27 years consisted of 25 people with emmetropia (spherical equivalent refraction [SER] +0.21 ± 0.36 diopters [D]) and 45 people with myopia (-2.84 ± 1.72 D). There were 23 people with low myopia (>-3 D) and 22 people with moderate myopia (-3 to -6 D). Right eye ciliary muscles were imaged (Visante OCT; Carl Zeiss Meditec) at 0 D and 6 D demands. Measures included ciliary muscle length (CML), ciliary muscle curved length (CMLarc), maximum ciliary muscle thickness (CMTmax), CMT1, CMT2, and CMT3 (fixed distances 1-3 mm from the scleral spur), CM25, CM50, and CM75 (proportional distances 25%-75%). Linear mixed model analysis determined effects of refractive groups, race, and demand on dimensions. Significance was set at P < 0.05.
    Results: Myopic eyes had greater CML and CMLarc nasally than emmetropic eyes. Myopic eyes had thicker muscles than emmetropic eyes at nasal positions, except CM25 and CMT3, and at CM75 temporally. During accommodation and only nasally, CML reduced in emmetropic and myopic eyes, and CMLarc reduced in myopic eyes only. During accommodation, both nasally and temporally, muscles thickened anteriorly (CMT1 and CM25) and thinned posteriorly (CMT3 and CM75) except for temporal CM75. Moderate myopic eyes had greater temporal CMLarc than low myopic eyes, and the moderate myopes had thicker muscles both nasally and temporally using fixed and proportional distances.
    Conclusions: People with myopia had longer and thicker ciliary muscles than people with emmetropia. During accommodation, the anterior muscle thickened and the curved nasal muscle length shortened, more in myopic than in emmetropic eyes. The fixed distance method is recommended for repeat measures in the same individual. The proportional distance method is recommended for comparisons between refractive groups.
    MeSH term(s) Adult ; Ciliary Body/physiology ; Emmetropia ; Humans ; Muscle, Smooth ; Myopia ; Tomography, Optical Coherence
    Language English
    Publishing date 2022-06-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 391794-0
    ISSN 1552-5783 ; 0146-0404
    ISSN (online) 1552-5783
    ISSN 0146-0404
    DOI 10.1167/iovs.63.6.24
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 45: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  10. Article ; Online: Characterisation and Modelling of an Artificial Lens Capsule Mimicking Accommodation of Human Eyes.

    Wei, Huidong / Wolffsohn, James S / Gomes de Oliveira, Otavio / Davies, Leon N

    Polymers

    2021  Volume 13, Issue 22

    Abstract: A synthetic material of silicone rubber was used to construct an artificial lens capsule (ALC) in order to replicate the biomechanical behaviour of human lens capsule. The silicone rubber was characterised by monotonic and cyclic mechanical tests to ... ...

    Abstract A synthetic material of silicone rubber was used to construct an artificial lens capsule (ALC) in order to replicate the biomechanical behaviour of human lens capsule. The silicone rubber was characterised by monotonic and cyclic mechanical tests to reveal its hyper-elastic behaviour under uniaxial tension and simple shear as well as the rate independence. A hyper-elastic constitutive model was calibrated by the testing data and incorporated into finite element analysis (FEA). An experimental setup to simulate eye focusing (accommodation) of ALC was performed to validate the FEA model by evaluating the shape change and reaction force. The characterisation and modelling approach provided an insight into the intrinsic behaviour of materials, addressing the inflating pressure and effective stretch of ALC under the focusing process. The proposed methodology offers a virtual testing environment mimicking human capsules for the variability of dimension and stiffness, which will facilitate the verification of new ophthalmic prototype such as accommodating intraocular lenses (AIOLs).
    Language English
    Publishing date 2021-11-12
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2527146-5
    ISSN 2073-4360 ; 2073-4360
    ISSN (online) 2073-4360
    ISSN 2073-4360
    DOI 10.3390/polym13223916
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

To top