A5068820925- Corneal surgery and disorders
- Corneal Surgery and Treatments
- Ocular Surface and Contact Lens
- Glaucoma and retinal disorders
- Collagen: Extraction and Characterization
- Connective tissue disorders research
- Periodontal Regeneration and Treatments
- Proteoglycans and glycosaminoglycans research
- Protease and Inhibitor Mechanisms
- Spectroscopy Techniques in Biomedical and Chemical Research
- Tendon Structure and Treatment
- Skin Protection and Aging
- Ophthalmology and Visual Impairment Studies
- Veterinary Equine Medical Research
- Intraocular Surgery and Lenses
- Spaceflight effects on biology
- X-ray Spectroscopy and Fluorescence Analysis
- Connexins and lens biology
- Mesenchymal stem cell research
- Cardiac Arrhythmias and Treatments
- Animal Disease Management and Epidemiology
- Marine and fisheries research
- Atrial Fibrillation Management and Outcomes
- Zoonotic diseases and public health
- Venous Thromboembolism Diagnosis and Management
Western Michigan University
2024-2025
Stryker (United States)
2024-2025
Stony Brook University
2025
Cardiff University
2013-2024
Stanford University
2018
Medical Research Council
2015
King Saud University
2015
St Thomas' Hospital
2015
To map the collagen orientation and relative distribution of fibrillar mass in keratoconus corneal buttons.Structural analysis was performed by obtaining synchrotron x-ray scattering patterns across samples at 0.25-mm intervals. The were analyzed to produce two-dimensional maps lamellae total preferentially aligned lamellae.Compared with normal corneas, gross organization stromal dramatically changed, unevenly distributed, particularly around presumed apex cone.The development involves a...
Purpose To examine the effect of riboflavin/UVA corneal crosslinking on stromal ultrastructure and hydrodynamic behaviour. Methods One hundred seventeen enucleated ungulate eyes (112 pig 5 sheep) 3 pairs rabbit eyes, with epithelium removed, were divided into four treatment groups: Group 1 (28 pig, 2 sheep rabbits) untreated; (24 pig) exposed to UVA light (3.04 mW/cm2) for 30 minutes (29 4 (31 had riboflavin eye drops applied surface every 35 minutes. Five after initial instillation, corneas...
Purpose. To study the distribution and predominant orientations of fibrillar collagen at different depths throughout entire thickness human cornea. This information will form basis a full three-dimensional reconstruction preferred corneal lamellae. Methods. Femtosecond laser technology was used to delaminate central zones five corneas into three separate layers (anterior, mid, posterior stroma), each with predetermined thicknesses. Wide-angle x-ray diffraction gross fibril orientation...
The severe worldwide shortage of donor organs, and pathologies placing patients at high risk for rejecting conventional cornea transplantation, have left many corneal blind untreated. Following successful pre-clinical evaluation in mini-pigs, we tested a biomaterials-enabled pro-regeneration strategy to restore integrity an open-label observational study six patients. Cell-free implants comprising recombinant human collagen phosphorylcholine were grafted by anterior lamellar keratoplasty...
Aspects of the biomechanics and surface topography fellow human corneas are known to exhibit midline symmetry, but structural basis these observations is poorly understood. The mechanical performance cornea strongly influenced by organization stromal collagen fibrils. present study was designed examine compare fibrils in corneal stroma left right eyes.Wide-angle x-ray scattering used map detail orientation distribution fibrillar across cornea, limbus, adjacent sclera three normal eyes,...
PURPOSE: To evaluate the importance of complete epithelial removal before riboflavin–ultraviolet-A (UVA) corneal collagen crosslinking therapy. SETTING: School Optometry and Vision Sciences, Cardiff University, Wales, United Kingdom. METHODS: Riboflavin eyedrops were applied at 5-minute intervals for 35 minutes to anterior surface 36 porcine eyes (12 with no trauma but treated tetracaine eyedrops, 12 superficial an intact basal epithelium, a fully removed epithelium). The 6...
Fibrillar collagen in the human cornea is integral to its function as a transparent lens of precise curvature, and arrangement now well-characterised literature. While there has been considerable effort incorporate fibrillar architecture into mechanical models cornea, response corneal small applied loads not well understood. In this study molecular tensile load was quantified using wide angle X-ray scattering (SAXS/WAXS), digital image correlation (DIC) photography used calculate local...
It is thought that corneal surface topography may be stabilized by the angular orientation of out-of plane lamellae insert into anterior limiting membrane. In this study, micro-focus X-ray scattering data were used to obtain quantitative information about lamellar inclination (with respect surface) and scatter intensity throughout depth cornea from centre temporal limbus. The average collagen remained predominantly parallel tissue at all depths. However, in central cornea, spread angles was...
Keratoconus, a disorder characterized by corneal thinning and weakening, results in vision loss. Corneal crosslinking (CXL) can halt the progression of keratoconus. The development accelerated (A-CXL) protocols to shorten treatment time has been hampered rapid depletion stromal oxygen when higher UVA intensities are used, resulting reduced cross-linking effect. It is therefore imperative develop better methods increase concentration within stroma during A-CXL process. Photocatalytic...
Abstract This study is a comparative of the relationship between corneal structure, morphology, and function in range mammalian species. X‐ray scattering patterns were gathered at regular spatial intervals over excised cornea (and most cases also scleral rim) humans, marmosets, horses, cows, pigs, rabbits, mice. All analyzed to produce quantitative information regarding predominant orientation fibrillar collagen throughout tissue. The direction varies mammals. variation not related size,...
Purpose: To compare stromal riboflavin absorption after 20% alcohol application and partial or complete epithelial removal by analyzing light transmission properties of porcine corneas riboflavin/ultraviolet A (UVA) corneal collagen cross-linking. Methods: Riboflavin 0.13% eye drops were applied to 18 eyes (6 in which solution had been for 40 seconds, 6 with a grid pattern full-thickness trauma, the central epithelium fully removed) at 5-minute intervals 35 minutes. In all eyes, surface was...
Purpose To determine the effect of Ultraviolet-A collagen cross-linking with hypo-osmolar and iso-osmolar riboflavin solutions on stromal ultrastructure in normal keratoconus ex vivo human corneas. Methods Using small-angle X-ray scattering, measurements D-periodicity, fibril diameter interfibrillar spacing were made at 1 mm intervals across six post-mortem corneas (two above physiological hydration (swollen) four below (unswollen)) two post-transplant corneal buttons (one swollen; one...
The mouse has become an important wound healing model with which to study corneal fibrosis, a frequent complication of refractive surgery. aim the current was quantify changes in stromal ultrastructure and light scatter that characterize fibrosis debridement wounds.Epithelial wounds, without removal basement membrane, were produced C57BL/6 mice. Corneal opacity measured using optical coherence tomography, collagen diameter matrix order quantified by x-ray scattering. Electron microscopy used...
Purpose To examine the effect of standard and accelerated corneal collagen crosslinking (CXL) on enzymatic resistance. Setting School Optometry Vision Sciences, Cardiff University, Cardiff, United Kingdom. Design Experimental study. Methods Sixty-six enucleated porcine eyes (with epithelium removed) were assigned to 6 groups. Group 1 remained untreated, group 2 received dextran eyedrops, groups 3 riboflavin/dextran eyedrops. 4 had CXL (3 mW/cm2 ultraviolet-A for 30 minutes), whereas 5 (9 10...
Infections with coagulase negative staphylococcal species (CoNS) are a major cause of mortality and morbidity in joint heart valve replacement procedures, largely due to biofilm formation. Cells within biofilms have higher rates antibiotic resistance than their planktonic counterparts; consequently, novel mechanisms needed combat these infections. To enhance delivery penetration, this innovative study involved treating CoNS murine blood clots impregnated antibiotics. We then investigated the...
The structural and optical properties of clinically biocompatible, cell-free hydrogels comprised synthetically cross-linked moulded recombinant human collagen type III (RHCIII) with without the incorporation 2-methacryloyloxyethyl phosphorylcholine (MPC) were assessed using transmission electron microscopy (TEM), X-ray scattering, spectroscopy refractometry. These findings examined alongside similarly obtained data from 21 donor corneas. TEM demonstrated presence loosely bundled aggregates...
Abstract Purpose To indirectly measure stromal riboflavin penetration using commercially available solutions and new existing epithelium‐off, trans‐epithelial iontophoresis‐assisted delivery protocols. Methods Forty porcine eyes were divided into eight groups. Group 1: Ricrolin applied to the de‐epithelialised cornea for 30 min; 2: epithelium‐intact, no treatment; Groups 3–5: 30‐min application of TE , Mediocross or ParaCel/Vibex, respectively. 6: + 5 7: min with a 20‐min soak; 8: min,...
Purpose: To investigate the effect of various riboflavin/ultraviolet light (UVA) crosslinking (CXL) protocols on corneal enzymatic resistance. Methods: A total 66 enucleated porcine eyes, with epithelium removed, were divided into 6 groups. Group 1 remained untreated. Groups 2 to received riboflavin/dextran for 30 minutes. 3 underwent standard CXL (SCXL) mW/cm2 UVA minutes (total energy dose 5.4 J/cm2). 4 and 5 high intensity (HCXL) using (5.4 J/cm2) (7.2 J/cm2), respectively. was exposed 8...