Slit lamp photography for objective assessment of topical eye disorders

Evidence based scientific studies has weightage, when they are presented with quantitative data analysis. Documentation and parametric analysis has become an integral part of present day research. Any publications or write-ups without explanation through standard parameters are not appreciated by the research society. In Ophthalmology assessment of various parameters through photography is a debatable issue. Affordability for higher end diagnostic / OPD instruments may not be feasible for all. In such a scenario, here is an attempt made to standardize the slit lamp photography with a smart phone and its scientific analysis for evaluating clinical conditions like sub-conjunctival hemorrhage, etc. This technique can become a tool for assessment and response of the therapies as well as an important tool to seek help from higher centers. Various add-on benefits in research, limitation and scope for further evaluation also being discussed.

A multi-parameter grading system for optimal fitting of scleral contact lenses

Background: While scleral lens practise has improved over the years due to factors such as availability of lenses with better materials and designs as well as experience of practitioners, a lack of objectivity appears to remain in terms of assessment of scleral lens fitting. This prospective observational work aimed to achieve standardization on this front through proposing a grading system for scleral lens fitting. Methods: After application of prosthetic replacement of ocular surface ecosystem (PROSE) devices on the participants’ eyes, four fundamental components for understanding scleral lens fitting such as central and limbal corneal clearance, mid-haptic compression, and alignment of lens edge over anterior sclera were assessed through a series of slit-lamp biomicroscopy imaging as well as with anterior segment optical coherence tomography. FitConnect® was used to modify the device parameters to simulate different grading patterns on the proposed scale. Serial imaging was done for all the different lenses to compose the grading scale. Results: A clinically relevant grading scale was constructed that pictorially demonstrated grades for the different aspect of scleral lens fitting. The grades were conveniently scaled within three categories: “optimal”, “acceptable” and “not acceptable”. Conclusion: The gradation of scleral lens fitting parameters would take a step towards objectifying the assessment patterns in practise. This will also help reducing the gap between a novice and an experienced practitioner in terms of understanding of scleral lens fitting.

Semi-MsST-GAN: A Semi-Supervised Segmentation Method for Corneal Ulcer Segmentation in Slit-Lamp Images

Corneal ulcer is a common leading cause of corneal blindness. It is difficult to accurately segment corneal ulcers due to the following problems: large differences in the pathological shapes between point-flaky and flaky corneal ulcers, blurred boundary, noise interference, and the lack of sufficient slit-lamp images with ground truth. To address these problems, in this paper, we proposed a novel semi-supervised multi-scale self-transformer generative adversarial network (Semi-MsST-GAN) that can leverage unlabeled images to improve the performance of corneal ulcer segmentation in fluorescein staining of slit-lamp images. Firstly, to improve the performance of segmenting the corneal ulcer regions with complex pathological features, we proposed a novel multi-scale self-transformer network (MsSTNet) as the MsST-GAN generator, which can guide the model to aggregate the low-level weak semantic features with the high-level strong semantic information and adaptively learn the spatial correlation in feature maps. Then, to further improve the segmentation performance by leveraging unlabeled data, the semi-supervised approach based on the proposed MsST-GAN was explored to solve the problem of the lack of slit-lamp images with corresponding ground truth. The proposed Semi-MsST-GAN was comprehensively evaluated on the public SUSTech-SYSU dataset, which contains 354 labeled and 358 unlabeled fluorescein staining slit-lamp images. The results showed that, compared with other state-of-the-art methods, our proposed method achieves better performance with comparable efficiency.

Slit Lamp Examination on Pediatric Patients

Slit lamp examination is an important component of a pediatric eye exam. The slit lamp instrument, also known as a biomicroscope, is used to provide a stereoscopic magnified view of the ocular structures. The slit lamp facilitates the examination of both the anterior segment as well as the posterior segment of the eyes. For posterior segment examination, handheld lenses are used in conjunction with the slit lamp. Different tools and examination techniques are often needed to examine infants, toddlers, and other pediatric patients who cannot be positioned in the slit lamp. This chapter discusses the techniques and equipment used to facilitate the ocular health examination, including anterior segment structures, posterior segment structures, and intraocular pressure measurements in the pediatric population.

Necrotizing Anterior Scleritis in a Woman with Terrien’s Marginal Degeneration: A Case Report

Purpose: The aim of the study was to report the first case of a patient with Terrien’s Marginal Degeneration (TMD) who developed necrotizing anterior scleritis without systemic disease association, requiring systemic immunosuppressive treatment. Case Report: A 32-year-old female consulted for bilateral ocular burning and hyperemia. Initially, she was diagnosed with conjunctivitis and treated with topical antibiotics and corticosteroids, with mild transitory improvement but the progression of the disease. Years later, she attended the ocular immunology consultation for a second opinion where TMD with ocular inflammatory component OU was diagnosed. Seven months later, she presented with severe pain, decreased visual acuity, and photophobia in OS. At the slit-lamp examination, necrotizing anterior scleritis with a high risk of perforation in OS was observed. The patient was referred to the rheumatologist and started treatment with systemic corticosteroids and cyclophosphamide, exhibiting a clinical improvement. The patient did not meet the criteria for any systemic illness associated with scleritis, such as autoimmune diseases or vasculitis. Thus, scleritis was related to the adjacent inflammatory process associated with TMD, as an atypical presentation of this disease. Conclusion: Although an inflammatory type of TMD has been proposed, it is essential to follow up closely these patients and consider necrotizing anterior scleritis, a severe ocular disease that requires prompt immunosuppressive management, as a possible atypical associated presentation of this disease.

Frequently Experienced Problems in the Early Stages after Prescribing Rigid Gas Permeable Contact Lenses

Prescribing rigid gas-permeable (RGP) lenses involves a series of processes that determine the most appropriate final lens through the trial use of test lenses based on the results of slit lamp microscopy, measuring refraction and corneal curvature, and corneal topography. The final prescription is reached by judging the dynamic lens movement, adequacy of the tear layer around the lens, corrected vision, and quality of vision. Various problems are encountered soon after prescribing lenses, including foreign body sensation, tear hypersecretion, decreased visual acuity, blurring, visual acuity change, redness, dryness, sudden pain, lens centering, and lens fallout. Here, we examine these problems and how to solve them.

Continuous administration of voriconazole enhances therapeutic effect for recalcitrant fungal keratitis

Purpose To evaluate the therapeutic effect of incorporating continuous administration of voriconazole in the treatment of recalcitrant fungal keratitis. Methods In this prospective case study, 5 consecutive patients (5 eyes) with fungal keratitis were treated with a standard protocol after the failing maximal conventional medical treatment. The protocol involved continuous lavage of the ulcer with 1% voriconazole through an irrigator for 2 h, twice a day, combined with local and systemic antifungals. Visual acuity, slit lamp findings of the ulcer, and fungal hyphae density by confocal microscope were documented, respectively. Results In 4 patients, the clinical symptoms and slit lamp examination were significantly improved after only 3 days of treatment. The hyphae were shown to decrease in number and morphologically fragmented in corneal stroma by confocal microscopy. After the infection was controlled, 2 cases required further keratoplasty. In one case, the treatment was deemed ineffective and a conjunctival flap had to be created to help control the infection. In all 5 patients, the best spectacle-corrected visual acuity had improved after treatment. With more than 3 months of follow-up, no recurrence of infection was seen in any cases. Conclusion Our treatment protocol demonstrated improvement in the treatment of clinically resistant fungal keratitis. Continuous lavage of voriconazole is easy to be implemented and well-tolerated by patients. Modification of the current protocol should be further explored to optimize the therapeutic effectiveness in future.

Keratitis Treatment by Removal of Concealed Retrocorneal Plant Foreign Body

Purpose: We report a case of keratitis that improved after removal of a causative plant foreign body from below the posterior surface of an opaque cornea. The foreign body was revealed by anterior segment optical coherence tomography (AS-OCT) and gonioscopy.Case summary: A 79-year-old woman was referred with an impression of left-eye keratitis; the eye had been injured by a branch of a tangerine tree 1 month prior. She had been given the usual topical antibiotics by a local clinic, but they were ineffective. At her initial visit, her visual acuity was only hand motion in the left eye; slit-lamp examination revealed a 3 × 3-mm corneal infiltration with a hypopyon in the anterior chamber. Despite administration of strong topical antibiotics on an hourly basis, the corneal lesion worsened. AS-OCT and gonioscopy revealed a small foreign body below the posterior surface of the cornea; this was surgically removed. The corneal opacity and corneal epithelial defects dramatically improved, and the hypopyon disappeared.Conclusions: The possibility of a residual foreign body should be considered if trauma precedes infectious keratitis that does not improve with conventional treatment and the posterior surface of the cornea is not visible because of corneal opacity. In such a case, AS-OCT and gonioscopy can be useful.

A Liquid Hydrogel to Restore Long Term Corneal Integrity After Perforating and Non-Perforating Trauma in Feline Eyes

Purpose: To evaluate long-term in vivo functionality of corneas regenerated using a cell-free, liquid hydrogel filler (LiQD Cornea) after deep corneal trauma in the feline model.Methods: Two healthy cats underwent 4 mm diameter stepwise 250/450 µm deep surgical corneal ablation with and without needle perforation. The filler comprising 10% (w/w) collagen-like peptide conjugated to polyethylene glycol (CLP-PEG) and 1% fibrinogen and crosslinked with 2% (w/w) 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM), was applied to the wound bed previously coated with thrombin (250 U/ml). In situ gelation occurred within 5 min, and a temporary tarsorrhaphy was performed. Eyes were examined weekly for 1 month, then monthly over 12 months. Outcome parameters included slit-lamp, Scheimpflug tomography, optical coherence tomography, confocal and specular microscopy, and immunohistochemistry studies.Results: The gelled filler was seamlessly incorporated, supporting smooth corneal re-epithelialization. Progressive in-growth of keratocytes and nerves into the filler corresponding to the mild haze observed faded with time. The regenerated neo-cornea remained stably integrated throughout the 12 months, without swelling, inflammation, infection, neovascularization, or rejection. The surrounding host stroma and endothelium remained normal at all times. Tomography confirmed restoration of a smooth surface curvature.Conclusion: Biointegration of this hydrogel filler allowed stable restoration of corneal shape and transparency in the feline model, with less inflammation and no neovascularization compared to previous reports in the minipig and rabbit models. It offers a promising alternative to cyanoacrylate glue and corneal transplantation for ulcerated and traumatized corneas in human patients.