Do pathogens from corneal scraping show their true colours better in bactec bottles?

Identification of causative organisms of clinically suspected microbial keratitis is very important so that appropriate targeted antimicrobial treatment can be offered to patients. The current routine method of corneal scraping specimens on to multiple agar culture plates for microbiological study is not really providing encouraging result. Our trial of modified technique of using BACTEC broth for three clinically suspected microbial keratitis cases worked 100% to identify the causative organisms in cases of microbial keratitis

Therapeutic and Tectonic Penetrating Keratoplasty- All in One

A middle-aged gentleman with history of left penetrating keratoplatsy presented with left eye perforated corneal graft secondary to infective keratitis. The affected eye was blind from absolute steroid-induced glaucoma. In view of expected poor graft survival in a blind eye, globe removal was offered. However, the patient refused the treatment and request for another corneal graft. This case highlights both the possibility of good outcome of cornea graft in such a case, and also illustrates that patient’s autonomy to refuse treatment option outweighs beneficence

Online Monitoring of the Mechanical Behavior of Collagen Hydrogels: Influence of Corneal Fibroblasts on Elastic Modulus

Collagen hydrogels have been widely used to model biological systems and examine cell behavior in vitro. Of increasing interest is how cells affect the mechanical characteristics of their surrounding matrix and vice versa over long culture periods. In this study, the change in mechanical properties of collagen hydrogels embedded with human corneal fibroblasts was examined over a 6-week culture period using a novel online spherical indentation system. The elastic modulus of the hydrogels was found to increase during the first 2 weeks of culture and decrease after 4 weeks in culture. The effects of actin polymerization and matrix metalloproteinase inhibitors were also examined, which verified some mechanisms involved in the alteration of the mechanical properties such as cell tensile forces and other potential factors. This online monitoring technique demonstrates the ability to examine the mechanical properties of cell-seeded constructs in response to the culture environments-in particular, the response to the addition of drugs or chemical reagents-which will provide a useful tool in studying the mechano-feedback loop between cells and their surrounding matrix

Suturing techniques and postoperative management in penetrating keratoplasty in the United Kingdom

Richard MH Lee,1 Fook Chang Lam,1 Tassos Georgiou,1 Bobby Paul,1 Kong Yong Then,1 Ioannis Mavrikakis,1 Venkata S Avadhanam,1 Christopher SC Liu1,21Sussex Eye Hospital, Brighton, United Kingdom; 2Tongdean Eye Clinic, Hove, United KingdomAims: To report on the suturing techniques and aspects of postoperative management in penetrating keratoplasty in the United Kingdom.Methods: A postal questionnaire was sent to 137 ophthalmic consultants identified from a Royal College of Ophthalmology database as having a special interest in anterior segment surgery. The questionnaire surveyed surgeon preferences for surgical and suturing technique for penetrating keratoplasty surgery, and the postoperative care of corneal grafts.Results: In all, 68% of questionnaires were completed and returned: 73% of respondents used a Flieringa ring or equivalent, 94% routinely used cardinal sutures, with 50.5% removing them at the end of the procedure. The most common suturing technique for routine penetrating keratoplasty was a single continuous suture (35%). In these cases, a 10/0 nylon suture was used by 89%. Sixty-six percent changed their technique in high-risk cases, 52% used a 3-1-1 knot, and 75% made a distinction between a reef and granny knot, with 76% using a reef. Thirty percent buried the knots within the donor material, and 29% within the host tissue. Twenty-five percent had no routine time for graft suture removal, but 41% removed them between 1 and 2 years post-surgery. After suture removal, 98% used steroids and 88% used topical antibiotics. Thirty-four percent stopped topical steroids before suture removal, with 38% stopping topical steroids more than 3 months prior to suture removal.Conclusion: This survey demonstrates that there is considerable variation in suturing techniques and postoperative care for penetrating keratoplasty. These significant variations in practice need to be considered when interpreting outcomes and research.Keywords: corneal graft, penetrating keratoplasty, anterior segment surgery, cornea, corneal surgery, corneal transplantatio

Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer

Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases