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Wilson S.L.,Keele University | Wimpenny I.,Keele University | Ahearne M.,Keele University | Rauz S.,Birmingham and Midland Eye Center | And 2 more authors.
Advanced Functional Materials | Year: 2012

Control and maintenance of the keratocyte phenotype is vital to developing in vitro tissue engineered strategies for corneal repair. In this study the influence of topographical and chemical cues on the mechanical, phenotypical and genotypical behaviour of adult human derived corneal stromal (AHDCS) cells in three dimensional (3D) multi-layered organised constructs is examined. Topographical cues are provided via multiple aligned electrospun nanofiber meshes, which are arranged orthogonally throughout the constructs and are capable of aligning individual cells and permitting cell migration between the layers. The influence of chemical cues is examined using different supplements in culture media. A non-destructive indentation technique and optical coherence tomography are used to determine the matrix elasiticity (elastic modulus) and dimensional changes, respectively. These measurements were indicative of changes in cell phenotype from contractile fibroblasts to quiescent keratocytes over the duration of the experiment and corroborated by qPCR. Constructs containing nanofibers have a higher initial modulus, reduced contraction and organised cell orientation compared to those without nanofibers. Cell-seeded constructs cultured in serum-containing media increased in modulus throughout the culture period and underwent significantly more contraction than constructs cultured in serum-free and insulin-containing media. This implies that the growth factors present in serum promote a fibroblast-like phenotype; qPCR data further validates these observations. These results indicate that the synergistic effect of nanofibers and serum-free media plus insulin supplementation provide the most suitable topographical and chemical environment for reverting corneal fibroblasts to a keratocyte phenotype in a 3D construct. A novel engineering strategy is devised to create a nanofiber-hydrogel composite scaffold, which displays the characteristic morphological cues of native corneal tissue. Investigation of cell response to nanofibrous topographical cues, combined with media supplementation, highlighted that orthogonal arrangement of adult human derived corneal stromal (AHDCS) cells in 3D constructs with the presence of insulin and ascobate promotes keratogenesis, which could be a new strategy for generation of complex corneal tissue. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Batra R.,University of Birmingham | Batra R.,Birmingham and Midland Eye Center | Tailor R.,University of Birmingham | Mohamed S.,University of Birmingham
Journal of Glaucoma | Year: 2014

Purpose: To describe a series of 4 patients with inadequately controlled primary open angle glaucoma and ocular surface disease (OSD) in whom a combination approach was used to manage the OSD resulting in improved intraocular pressure (IOP) control. PAtients and methods: A retrospective review of the clinical notes of 4 patients referred to a tertiary surgical glaucoma service was performed. At the initial visit, measures to control the OSD were employed in all patients; twice-daily lid hygiene measures, a 3-month course of 50 mg daily oral doxycycline, topical carmellose sodium (celluvisc) 0.5% 4 to 6 times daily, and preservative-free equivalents of topical antiglaucoma medications as deemed appropriate, depending on the perceived severity of the OSD. Results: Patients were reviewed for a maximum of 24 months after intervention. In all patients treatment resulted in a marked symptomatic and clinical improvement in the ocular surface with a reduction in hyperemia, meibomian gland dysfunction and superficial keratopathy. A reduction in the IOP also occurred in all patients, obviating the need for glaucoma drainage surgery during the study period. Conclusions: Patients with severe OSD often have glaucoma that is refractive to medical therapy. Furthermore, the surgical success of glaucoma filtering surgery is compromised in patients with scarring and inflammation of the conjunctiva. The term we postulate is "OSD exacerbated glaucoma." This is the first study to suggest that the use of a combination approach comprising medical treatment to manage the OSD in patients with primary open angle glaucoma may lead to an improvement in the IOP control and the management of glaucoma. Copyright © 2013 by Lippincott Williams & Wilkins.

Jackson T.E.,Birmingham and Midland Eye Center | Sandramouli S.,Wolverhampton Eye Infirmary
Journal of Neuro-Ophthalmology | Year: 2012

Synesthesia is an unusual condition in which stimulation of one sensory modality causes an experience in another sensory modality or when a sensation in one sensory modality causes another sensation within the same modality. We describe a previously unreported association of auditory-olfactory synesthesia coexisting with auditory-visual synesthesia. Given that many types of synesthesias involve vision, it is important that the clinician provide these patients with the necessary information and support that is available. Copyright © 2012 North American Neuro-Ophthalmology Society.

Bhatnagar A.,Birmingham and Midland Eye Center
Ophthalmic surgery, lasers & imaging : the official journal of the International Society for Imaging in the Eye | Year: 2010

Retinal burns of subthreshold intensity created using micropulsed diode laser, which remain clinically invisible, have been shown to be successful in treating macular edema while minimizing the risk of collateral damage to the retina. A study was conducted to determine whether spectral domain optical coherence tomography (SD-OCT) could be used to detect subthreshold retinal burns created using the 532-nm green wavelength laser. A series of retinal burns of gradually decreasing intensity were created in 10 eyes. Retinal burns produced with duration of laser exposure of 0.03 second or less, although clinically invisible, were detectable on the SD-OCT scan as increased retinal reflectivity confined to the outer retinal layers. This series demonstrates the potential of using SD-OCT imaging to verify delivery of subthreshold laser burns. Copyright 2010, SLACK Incorporated.

Mroczkowska S.,Aston University | Benavente-Perez A.,Aston University | Negi A.,Heart Health | Sung V.,Birmingham and Midland Eye Center | And 2 more authors.
Archives of Ophthalmology | Year: 2013

Objective: To compare and contrast the presence of ocular and systemic vascular function in patients with newly diagnosed and previously untreated primary openangle glaucoma (POAG) vs those with normal-tension glaucoma (NTG) and comparable early-stage, functional loss. Methods: The systemic vascular function of 19 patients with POAG, 19 patients with NTG, and 20 healthy individuals serving as controls was assessed using 24-hour ambulatory blood pressure monitoring, peripheral pulsewave analysis, and carotid intima-media thickness. Retinal vascular reactivity to flicker light was assessed using dynamic retinal vessel analysis (Imedos, GmbH). Results: Compared with controls, patients with POAG and those with NTG exhibited similarly increased nocturnal systemic blood pressure variability (P = .01), peripheral arterial stiffness (P = .02), carotid intima-media thickness (P = .04), and reduced ocular perfusion pressure (P < .001). Furthermore, on dynamic retinal vessel analysis, both glaucoma groups exhibited steeper retinal arterial constriction slopes after cessation of flicker (P = .007) and a similarly increased fluctuation in arterial and venous baseline diameter (P = .008 and P = .009, respectively) compared with controls. Conclusions: Patients with POAG or NTG exhibit similar alterations in ocular and systemic circulation in the early stages of their disease process. This finding highlights the importance of considering vascular risk factors in both conditions and raises questions about the current separation of the two conditions into distinct clinical entities. ©2013 American Medical Association. All rights reserved.

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