Ocular surface staining: Current concepts and techniques.

The health of the ocular surface is vital for clear vision and comfort. Various factors can adversely influence the ocular surface and tear film homeostasis, and these include procedures like cataract and corneal refractive surgery. It is, therefore, important to assess the integrity of the ocular surface in a rapid, predictable, and consistent manner in the clinic. Various tests and devices have been described, and while these are useful, this article highlights the importance of using fluorescein staining of the ocular surface in detecting changes. This is a simple, inexpensive, rapidly performed test that is available in most eye clinics. However, a proper technique of dye instillation and assessment is important to recognize the changes that can occur. Once detected, these changes can be quantified, and the location and patterns can be used to diagnose the diseases that are present; these changes can also be used to monitor treatment outcomes and disease progression. The article discusses the technique, assessment, and interpretation of fluorescein staining of the ocular surface, along with the role of the two other vital dyes - rose bengal and lissamine green.

Evaluation of ocular surface and tear function - A review of current approaches for dry eye.

An increasing prevalence of dry eye disease in the past decade has resulted in a greater focus on diagnostic methods for this condition. There has been a proliferation of technologies that attempt to quantify various aspects of tear function and ocular surface health. However, a cost-effective, simple, and efficient method remains elusive. In the Indian context, the majority of these patients present to the general ophthalmologist, and a clinical approach that is quick and easy to perform would allow widespread usage for accurate diagnosis. This article reviews currently available methods and their relevance to the general ophthalmologist.

Inflammation and dry eye disease-where are we?

The presence of inflammation in dry eye disease (DED) results in increased patient symptomatology, ocular surface damage and worsening tear dysfunction. It also affects the health of meibomian glands and their secretions which further aggravates ocular surface disease. This article reviews current knowledge regarding ocular surface inflammation in DED and explores the relationships between the vicious cycles of DED, inflammation and meibomian gland dysfunction (MGD). The clinical evaluation of eyes with such changes, markers that identify the presence of inflammation on the ocular surface and current treatment options are discussed.

A 3D Polymer Scaffold Platform for Enhanced in vitro Culture of Human & Rabbit Buccal Epithelial Cells for Cell Therapies.

BACKGROUND: Buccal mucosal epithelial cells show promising application for various regenerative medicine approaches. In this study, we examined the feasibility of culturing rabbit and human buccal mucosal epithelial cells in a novel thermoreversible gelation polymer (TGP) scaffold, without feeder layers or other foreign proteins. METHODS & RESULTS: The results of this 28-day in vitro culture, u sing the conventional technique (2D) and TGP (3D) showed that the epithelial cell morphology could be maintained only in the TGP group while cells in the 2D group de-differentiated to fibroblast morphology in both human and rabbit samples. CK3 expression, a marker for epithelial differentiation was higher in 3D-TGP cultured cells than 2D. CONCLUSION: TGP based in vitro cell culture is a prospective methodology to culture buccal mucosal epithelial cells efficiently without using foreign biological components for tissue engineering applications.

Cataract.

Cataract is the leading cause of reversible blindness and visual impairment globally. Blindness from cataract is more common in populations with low socioeconomic status and in developing countries than in developed countries. The only treatment for cataract is surgery. Phacoemulsification is the gold standard for cataract surgery in the developed world, whereas manual small incision cataract surgery is used frequently in developing countries. In general, the outcomes of surgery are good and complications, such as endophthalmitis, often can be prevented or have good ouctomes if properly managed. Femtosecond laser-assisted cataract surgery, an advanced technology, can automate several steps; initial data show no superiority of this approach over current techniques, but the results of many large clinical trials are pending. The greatest challenge remains the growing 'backlog' of patients with cataract blindness in the developing world because of lack of access to affordable surgery. Efforts aimed at training additional cataract surgeons in these countries do not keep pace with the increasing demand associated with ageing population demographics. In the absence of strategie that can prevent or delay cataract formation, it is important to focus efforts and resources on developing models for efficient delivery of cataract surgical services in underserved regions. For an illustrated summary of this Primer, visit: http://go.nature.com/eQkKll.

A literature review and case series of accelerating fracture healing in postmenopausal osteoporotic working women.

Majority of fractures do not cause significant long-term morbidity and mortality. A 10% of these fractures result in impaired fracture healing, drastically affecting quality of life in affected patients. Satisfactory healing of these osteoporotic fractures are critically important to functional recovery, morbidity, and quality of life. Some therapies for osteoporosis may affect the processes associated with bone repair. For example, bisphosphonates in experimental models are associated with increased callus size and mineralization, reduced callus remodeling, and improved mechanical strength. Local and systemic bisphosphonate treatment may improve implant fixation. No negative impact on fracture healing has been observed, even after major surgery or when administered immediately after fracture. For the osteoanabolic agent teriparatide, case reports and a randomized trial have produced mixed results, but they are consistent with a positive impact of teriparatide on fracture healing. At this point, therefore, there is no evidence that osteoporosis therapies are detrimental to fracture healing with some promising experimental evidence for positive effects on healing, notably for those agents whose actions are primarily anabolic.

Successful transportation of human corneal endothelial tissues without cool preservation in varying Indian tropical climatic conditions and in vitro cell expansion using a novel polymer.

BACKGROUND: Though the transplantation of human corneal endothelial tissue (CET) separated from cadaver cornea is in practice, its transportation has not been reported. We report the successful transportation of CET in varying Indian climatic conditions without cool preservation and the in vitro expansion of Human Corneal Endothelial Precursor Cells (HCEPCs) using a novel Thermo-reversible gelation polymer (TGP). MATERIALS AND METHODS: CET from cadaver corneas (n = 67), unsuitable for transplantation, were used. In phase I, CET was transported in Basal Culture Medium (Group I) and TGP (Group II) and in Phase II, in TGP cocktail alone, from three hospitals 250-2500 km away, to a central laboratory. The transportation time ranged from 6 h to 72 h and the outdoor temperature between 20°C and 41°C. On arrival, CET were processed, cells were expanded upto 30 days in basal culture medium (Group A) and TGP scaffold (Group B). Cell viability and morphology were documented and Reverse transcription polymerase chain reaction (RT-PCR) characterization undertaken. RESULTS: In Phase I, TGP yielded more viable cells (0.11 × 10(6) cells) than Group I (0.04 × 10(6) cells). In Phase II, the average cell count was 5.44 × 10(4) cells. During expansion, viability of HCEPCs spheres in TGP was maintained for a longer duration. The cells from both the groups tested positive for B-3 tubulin and negative for cytokeratins K3 and K12, thereby proving them to be HCEPCs. CONCLUSION: TGP preserves the CET during transportation without cool preservation and supports in vitro expansion, with a higher yield of HCEPCs, similar to that reported in clinical studies.

Long-term outcomes of endothelial keratoplasty in Chinese eyes at a University Hospital.

BACKGROUND: Endothelial keratoplasty (EK) is used increasingly for the management of cases with endothelial dysfunction. Long-term outcomes of the surgery are not widely reported in the literature. We report our experience of EK in Chinese eyes at a University teaching hospital. METHODS: Retrospective analysis was performed for all cases of EK performed between 2005 and 2009. Data analyzed included indication for surgery, associated surgical procedures, complications, best-corrected visual acuity (BCVA) and overall graft survival. RESULTS: Overall, 22 eyes of 21 patients underwent EK (13 males, 8 females, mean age 71.8 ± 11.3 years). Pseudophakic bullous keratopathy was the leading indication for surgery (n = 12) followed by Fuchs' endothelial dystrophy (n = 4), or both (n = 3). Other indications for surgery included failed penetrating keratoplasty (n = 2) and endothelial decompensation due to multiple surgeries (n = 1). Triple procedure was performed in 5 (22.7%) cases. Complications were noted in the form of postoperative interface hemorrhage (n = 2, 9%) and graft dislocation (n = 1, 4.5%). The mean postoperative endothelial cell density was 1069 ± 585.8 cells/mm(2). The mean postoperative pachymetry was 675.8 ± 108.5 µm. The mean preoperative and postoperative intraocular pressure was 11.3 ± 3.2 and 13.9 ± 4.5 mmHg respectively. At the last follow-up (mean, 47.4 ± 13.7 months), BCVA was ≥20/70 in 9 (40.9%) cases. Causes of poor BCVA included primary graft failure (n = 4), graft decompensation (n = 4), advanced glaucoma (n = 2) and irreversible graft rejection (n = 2). Graft remained clear in 12 (54.5%) cases at the last follow-up. Average graft survival was 19.7 ± 17.7 months (median 17.5 months). CONCLUSIONS: Nearly half of the EK grafts in our study survived over a period of five years. Graft failure, glaucoma and graft rejection were the main causes of poor graft survival.

Collagen cross linking: current perspectives.

Keratoconus is a common ectatic disorder occurring in more than 1 in 1,000 individuals. The condition typically starts in adolescence and early adulthood. It is a disease with an uncertain cause and its progression is unpredictable, but in extreme cases, vision deteriorates and can require corneal transplant surgery. Corneal collagen cross-linking (CCL) with riboflavin (C3R) is a recent treatment option that can enhance the rigidity of the cornea and prevent disease progression. Since its inception, the procedure has evolved with newer instrumentation, surgical techniques, and is also now performed for expanded indications other than keratoconus. With increasing experience, newer guidelines regarding optimization of patient selection, the spectrum of complications and their management, and combination procedures are being described. This article in conjunction with the others in this issue, will try and explore the uses of collagen cross-linking (CXL) in its current form.

A new era in corneal transplantation: paradigm shift and evolution of techniques.

Penetrating keratoplasty is the replacement of a diseased cornea with a full-thickness donor graft. In the last century, this 'gold standard' procedure was long established as the treatment of choice for various corneal diseases. The classical indications for a penetrating keratoplasty entailed optical, tectonic, therapeutic, and cosmetic issues. Over the past decade however, surgical advances have now enabled operations involving the cornea to be performed with a major shift in emphasis, such that penetrating keratoplasty has given way to lamellar (layered) keratoplasty. This review provides the latest updates on developments in the field of corneal transplantation and the nomenclature of different types of component surgery, particularly from the perspective of Hong Kong.

Severe and recurrent interface hemorrhage after endothelial keratoplasty.

PURPOSE: To report the occurrence and management of recurrent hemorrhage after Descemet stripping endothelial keratoplasty (DSEK) in a patient with pseudophakic bullous keratopathy. METHODS: An 84-year-old Chinese woman on two oral antiplatelet drugs underwent DSEK in her left eye. Preoperative best-corrected visual acuity was 20/30 OD and 14/200 OS. Intraoperative bleeding was noted from the iris root. Surgery was completed uneventfully, and interface was thoroughly irrigated in the end. Slit lamp examination on the first postoperative day showed a dense interface hemorrhage and an intraocular pressure of 24 mm Hg. Repeat interface irrigation was carried out on postoperative day 4, but the hemorrhage appeared again on the following day. Donor lenticule was well apposed to the corneal stroma, and visual acuity was hand motions in the operated eye. No further surgical interventions were performed. Corticosteroid eye drops were continued four times a day in the operated eye, and the patient was advised weekly follow-up. RESULTS: Over the next 4 weeks, the interface blood gradually started to clear from the central cornea. At the end of 4 months postoperatively, the interface hemorrhage disappeared completely. A final best-corrected visual acuity of 20/80 was achieved. Specular microscopy revealed an endothelial cell density of 1375 cells/mm2. CONCLUSIONS: Interface hemorrhage is a known complication after DSEK surgery. Recurrent hemorrhage may be expected in patients on oral antiplatelet treatment. In cases without associated graft dislocation, conservative management can still result in good visual outcome.

Osteo-odonto-keratoprosthesis - a maxillofacial perspective.

The OOKP (osteo-odonto-keratoprosthesis) is the treatment of choice for conditions like Stevens-Johnson syndrome, ocular cicatricial pemphigoid, trachoma, multiple failed grafts and chemical burns which are not amenable to penetrating keratoplasty. The OOKP is an autograft which replaces the cornea with a polymethacrylate cylinder mounted on a tooth-bone complex. The aim of this paper was to retrospectively analyze the records in 26 patients undergoing OOKP surgery between 2007 and 2011. The paper describes our experience with the procedure, with emphasis on its oral and maxillofacial aspects and management of associated complications. The aetiology of blindness in 23 patients was Stevens-Johnson's syndrome and chemical burns in three. Twenty-two patients had their maxillary canines, two had mandibular canines and two had maxillary first premolars as the choice of donor tooth. An oroantral fistula developed in four patients. One patient needed to undergo a surgical procedure for closure of the same. Roots of adjacent teeth were exposed in 12 patients. Twenty-four patients underwent both stages of the procedure with 19 being visually rehabilitated successfully. There was no improvement in the vision of four patients. One patient was lost to follow-up. Two patients have yet to undergo Stage 2.

Randomized double-masked controlled trial comparing pain scores with and without the use of supplementary 2% lidocaine gel in LASIK.

PURPOSE: To compare pain scores with and without supplementary topical 2% lidocaine gel in patients undergoing simultaneous bilateral laser-assisted in situ keratomileusis (LASIK) under topical anesthesia using 0.5% proparacaine eye drops. DESIGN: Randomized double-masked placebo-controlled trial. METHODS: Fifty-one Chinese subjects (102 eyes, with 51 eyes in each arm) were included. One eye was randomly allocated to have supplementary 2% lidocaine gel while the other eye received carbomer gel as control, in addition to topical 0.5% proparacaine. The pain scores for each eye during microkeratome flap creation, during laser ablation, and at 15, 30, and 45 minutes after LASIK were assessed. An overall pain score of the LASIK procedure was also obtained. Primary outcome measures were pain scores during and after LASIK. Secondary outcomes included need for additional topical anesthesia, patient cooperation score, and duration and complications of surgery. RESULTS: In the 2% lidocaine gel-treated group, the pain scores were significantly lower during microkeratome flap creation and laser ablation, and postoperatively at 30 and 45 minutes (P<.05 for all). Patients in the lidocaine gel group required less additional topical anesthesia (P=.0004) and were more cooperative (P=.019) as compared to the carbomer gel group. No surgical or postoperative complications were observed. CONCLUSIONS: The use of supplementary 2% lidocaine gel in LASIK is effective in lowering the pain experienced during and up to 45 minutes after LASIK.

Adjunctive effect of acupuncture to refractive correction on anisometropic amblyopia: one-year results of a randomized crossover trial.

OBJECTIVES: To evaluate the safety and adjunctive effect of acupuncture added to refractive correction for anisometropic amblyopia in younger children. DESIGN: Prospective, randomized, controlled, crossover trial. PARTICIPANTS: We included 83 children aged 3 to <7 years with untreated anisometropic amblyopia and baseline best-corrected visual acuity (BCVA) of 20/40 to 20/200 in the amblyopic eye. METHODS: Participants were randomized to receive spectacles alone (group 1; n = 42) or spectacles + acupuncture (group 2; n = 41) for 15 weeks, and were then crossed over to receive the other regimen for another 15 weeks. The BCVA in both eyes was measured at baseline and every 5 (±1) weeks for the initial 45 weeks and at 60 (±1) weeks. MAIN OUTCOME MEASURES: BCVA in the amblyopic eye at 15, 30, and 60 weeks. RESULTS: The mean baseline BCVA in the amblyopic eye was 0.50 and 0.49 logarithm of the minimum angle of resolution (logMAR) in groups 1 and 2, respectively. After 15 weeks of treatment, the BCVA had improved by a mean of 2.2 lines in group 1 and 2.9 lines in group 2. The mean difference in BCVA between groups was 0.77 lines (95% confidence interval (CI), 0.29-1.3; P = 0.0020) with baseline adjustment. BCVA of ≤0.1 logMAR was achieved in 14.6% of the patients in group 1 and 57.5% in group 2 (P<0.00010). After the regimens were crossed over at 30 weeks, group 1 had a mean of 1.2 (95% CI, 0.98-1.48; P = 2.0 × 10⁻¹²) lines additional improvement from the 15-week BCVA, whereas in group 2 the mean improvement was 0.4 (95% CI, 0.19-0.63; P = 0.0010) lines. The proportions of responders, resolution, and participants achieving a BCVA of ≤0.1 logMAR at 30 weeks were similar between groups. After completion of acupuncture, only 1 participant had >1 line of VA decrease to 60 weeks. Acupuncture was well-tolerated by all children, and no severe adverse effect was encountered. CONCLUSIONS: Acupuncture is a potentially useful complementary treatment modality that may provide sustainable adjunctive effect to refractive correction for anisometropic amblyopia in young children. Further large-scale studies seem warranted. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Association of hemopexin in tear film and conjunctival macrophages with vernal keratoconjunctivitis.

OBJECTIVE: Vernal keratoconjunctivitis (VKC) is a chronic allergic inflammatory disease with unclear etiology and pathogenesis. We investigated the tear film proteome of patients with VKC to understand the pathologic characteristics of VKC. METHODS: Tear samples were collected from healthy volunteers and patients with VKC. Electrophoresis was performed to display the tear proteomic profiles according to VKC severity. The identities of differentially expressed proteins were analyzed by mass spectrometry and quantified by enzyme-linked immunosorbent assay. Impression cytology was performed on VKC conjunctival samples to demonstrate the cellular protein expression. Allergic sensitization was performed in mice to study the pathologic role of these proteins in VKC. RESULTS: Hemopexin, an inflammatory protein, was elevated in the tear film of patients with VKC. The increased hemopexin concentration in VKC tears was significantly associated with disease severity. Impression cytology showed specific high hemopexin expression in dekeratinized conjunctival epithelium and necrotic macrophages in patients with VKC. Immunohistochemical examination of normal lacrimal tissues from mice showed that hemopexin was not expressed in any lacrimal apparatus. Under systemic and topical sensitization and challenge using hemopexin in mice, the affected eye had mild to moderate bead discharge, chemosis, and edema with excessive macrophage infiltration and conjunctival necrosis. CONCLUSION: An association exists between tear hemopexin and the development and pathologic effects of VKC. CLINICAL RELEVANCE: Increased hemopexin may have a role in the development of VKC.

Randomized controlled trial of patching vs acupuncture for anisometropic amblyopia in children aged 7 to 12 years.

OBJECTIVE: To compare the effectiveness of 2-hour daily patching with the effectiveness of acupuncture in treating anisometropic amblyopia in children aged 7 to 12 years who have worn optimal spectacles for at least 16 weeks. METHODS: In a single-center randomized controlled trial, 88 eligible children with an amblyopic eye who had a best spectacle-corrected visual acuity (BSCVA) of 0.3 to 0.8 logMAR at baseline were randomly assigned to receive 2 hours of patching of the sound eye daily or 5 sessions of acupuncture weekly. All participants in our study received constant optical correction, plus 1 hour of near-vision activities daily, and were followed up at weeks 5, 10, 15, and 25. The main outcome measure was BSCVA in the amblyopic eye at 15 weeks. RESULTS: The mean BSCVA of the amblyopic eye at 15 weeks improved from baseline by 1.83 and 2.27 lines in the patching and acupuncture groups, respectively. After baseline adjustment, the mean difference of BSCVA between the 2 groups was 0.049 logMAR (95% confidence interval, 0.005-0.092; P = .03), meeting the definition of equivalence (difference within 1 line). The BSCVA had improved by 2 lines or more in 28 (66.7%) and 31 (75.6%) eyes in the patching and acupuncture groups, respectively. Amblyopia was resolved in 7 (16.7%) and 17 (41.5%) eyes in the patching and acupuncture groups, respectively. CONCLUSION: Acupuncture produced equivalent treatment effect for anisometropic amblyopia, compared with patching, and was statistically superior. Further studies are warranted to investigate its value in the treatment of amblyopia. CLINICAL RELEVANCE: Acupuncture could potentially become an alternative treatment to occlusion therapy for amblyopia. TRIAL REGISTRATION: Centers for Clinical Trials Registry Identifier: CUHK_CCT00248.