Conjunctival flap surgery in the management of ocular surface disease (Review)

Amniotic membrane transplantation combined with conjunctival flap covering surgery for the treatment of corneal perforations in fungal keratitis

Purpose

To investigate the efficiency of amniotic membrane transplantation (AMT) combined with conjunctival flap covering surgery (CFCS) for patients with corneal perforations in fungal keratitis (FK).

Methods

In this non-comparative, retrospective case series, 16 participants of corneal perforation in FK were successfully treated by a combination of multilayer AMT and bipedicle conjunctival flap with partial tenon's capsule. Corneal healing, recurrence of FK, visual acuity, and relevant complications were reported as outcome measures.

Results

Sixteen patients (13 male, 3 female) had a mean age of 58.8 ± 10.3 (range 29-72) years. The mean diameter of corneal perforation was 1.9 ± 0.7 (range 0.5-2.8) mm. Corneal perforations healed and all the patients preserved their eyeballs. During the 11.0 ± 4.4 (range 6-18) months of follow-up, there was no recurrence of FK in any of these cases. Visual acuity improved in 15 eyes (93.8 %) and remained unchanged in 1 patient (6.3 %) who had no light perception when first admitted. All 6 patients who accepted secondary keratoplasty showed improved best corrected visual acuity of more than 4 lines. The most frequently found fungi were Aspergillus species (6 of 16, 37.5 %) and Fusarium species (4 of 16, 25.0 %), followed by 1 Scedosporium apiospermum (1 of 16, 6.3 %).

Conclusions

Combination AMT with CFCS is a safe and effective surgery for patients with corneal perforations in FK, particularly where eye banks and fresh corneas are not available. This surgery could preserve the integrity of the eyeball and avoid the recurrence of FK. Besides, it provides a greater opportunity for further optical keratoplasty.

Safety and Efficacy of Double Lamellar Keratoplasty for Corneal Perforation

INTRODUCTION

To assess the outcomes of double lamellar keratoplasty in the treatment of corneal perforation secondary to various keratopathies.

METHODS

In this prospective non-comparative interventional case series, 15 eyes from 15 consecutive patients with corneal perforation were chosen to undergo double lamellar keratoplasty, which is characterized by two layers of lamellar grafting in the perforated area. The posterior graft was separated from a relatively healthy and thin lamellar graft of the recipient, and the anterior graft was transplanted from the donor lamellar cornea. Preoperative characteristics and postoperative examination and relevant complications throughout the study were recorded.

RESULTS

Nine men and six women with an average age of 50.73 ± 19.89 (range, 9-84) years were enrolled. The median follow-up period was 18 (range, 12-30) months. In all postoperative patients, the integrity of the eyeball was successfully rebuilt, and the anterior chambers were formed without aqueous leakage. At the last visit, best-corrected visual acuity improved in 14/15 patients (93.3%). Slit-lamp microscopy showed that all treated eyes remained fully transparent. Anterior segment optical coherence tomography revealed that the double-layer structure of the treated cornea was clear in the early postoperative stage. In vivo confocal microscopy revealed intact epithelial cells, sub-basal nerves, and clear keratocytes in the transplanted cornea. No immune rejection or recurrence was detected during the follow-up period.

CONCLUSIONS

Double lamellar keratoplasty presents a new therapeutic option for patients undergoing corneal perforation, and it provides improvement in visual acuity and reduces the risk of postoperative adverse events.

Initial Healing Effects of Platelet-Rich Plasma (PRP) Gel and Platelet-Rich Fibrin (PRF) in the Deep Corneal Wound in Rabbits

Platelet concentrates (PCs), including platelet-rich plasma (PRP) gel and platelet-rich fibrin (PRF), are autologous blood-derived biomaterials containing numerous growth factors. This study aimed to evaluate the initial healing effects of PRP gel and PRF on deep corneal wounds. Thirty-three eyes from New Zealand white rabbits were divided into four groups: group 1, lamellar keratectomy (LK); group 2, LK + commercial porcine small intestinal submucosal membrane (SIS); group 3, LK + SIS + PRP gel; and group 4, LK + SIS + PRF. Postoperative clinical and histological findings were observed for eight weeks. Group 1 showed no neovascularization during the observation period, and incompletely recovered with a thin cornea. Group 2 showed active healing through neovascularization, and a thick cornea was regenerated through the sufficient generation of myofibroblasts. Although group 3 showed a healing effect similar to that of group 2, angiogenesis and subsequent vessel regression were promoted, and corneal opacity improved more rapidly. In group 4, angiogenesis was promoted during initial healing; however, the incidence of complications, such as inflammation, was high, and myofibroblasts were hardly generated in the corneal stroma, which adversely affected remodeling. In conclusion, while PRP gel is a safe surgical material for promoting remodeling through vascular healing and myofibroblast production in deep corneal wounds, the use of PRF is not recommended.

Surgical Treatment in Silicone Oil-Associated Glaucoma

Glaucoma is a vision threatening, not uncommon complication of eyes that have undergone pars plana vitrectomy with silicone oil endotamponade. Although most patients respond well to medical antiglaucoma therapy, there are refractory cases where surgery is required to control the intraocular pressure. This review, following a comprehensive literature search in the Medline database, aims to present the most important surgical techniques currently in use for glaucoma associated with silicone oil endotamponade and their indication depending on the mechanism of glaucoma. In cases of pupillary block, the presence of a patent iridotomy or iridectomy must be ensured, either by laser or surgically. When silicone oil is in excess and whenever the retinal status permits it, partial or complete removal of the silicone oil should be performed. Trabeculectomy has shown higher failure rates and more complications in these cases compared to other indications, so alternate methods are warranted. For very high intraocular pressures, glaucoma drainage devices and transscleral cyclophotocoagulation are the most used options, with good efficacy and safety profiles, although rarely they may have serious complications. The Ex-PRESS mini shunt has shown excellent results and lower rates of complications. For less important IOP elevations, minimally invasive glaucoma surgery and selective laser trabeculoplasty may be used, either alone or in conjunction with other methods.

Adherence to Therapy in Glaucoma Treatment—A Review

Glaucoma is a chronic disease and the second leading cause of irreversible vision loss worldwide, whose initial treatment consists of self-administered topical ocular hypotensive eyedrops. Adherence with glaucoma medications is a fundamental problem in the care of glaucoma patients as up to 50% of patients fail to receive the intended benefits of the treatment. The literature has identified many barriers to patients’ compliance, from factors depending on the type of medication administered, communication between physician and patients, to factors dependent on patients’ behaviour and lifestyle. Failure to take medication as prescribed increases the risk that patients will not receive the desired benefit, which often leads to a worsening of the disease. Our aim is to synthesize the methods used for measuring adherence of patients to glaucoma therapy and the interventions used for addressing adherence, laying emphasis on a patient-centred approach, taking time to educate patients about their chronic disease and to assess their views on treatment.

Biocompatible Materials for Orbital Wall Reconstruction-An Overview

The reconstruction of an orbit after complex craniofacial fractures can be extremely demanding. For satisfactory functional and aesthetic results, it is necessary to restore the orbital walls and the craniofacial skeleton using various types of materials. The reconstruction materials can be divided into autografts (bone or cartilage tissue) or allografts (metals, ceramics, or plastic materials, and combinations of these materials). Over time, different types of materials have been used, considering characteristics such as their stability, biocompatibility, cost, safety, and intraoperative flexibility. Although the ideal material for orbital reconstruction could not be unanimously identified, much progress has been achieved in recent years. In this article, we summarise the advantages and disadvantages of each category of reconstruction materials. We also provide an update on improvements in material properties through various modern processing techniques. Good results in reconstructive surgery of the orbit require both material and technological innovations.

Intraocular Pressure Measurement after Penetrating Keratoplasty

Assessing the intraocular pressure is a difficult but crucial task in the follow-up of patients that have undergone penetrating keratoplasty. Early recognition of elevated intraocular pressure and/or glaucoma and establishment of the appropriate treatment is essential to ensure the best possible visual outcome for patients dealing with this feared complication. Although Goldmann applanation tonometry is still the gold standard for measuring the intraocular pressure, its limitations in postkeratoplasty eyes, due to postoperative modified corneal morphology, have led to the search for more suitable alternatives. This review is the result of a comprehensive literature search in the MEDLINE database that aims to present glaucoma in the context of perforating keratoplasty, the corneal properties with impact on ocular pressure measurement, and the results achieved with the most important tonometers that have been studied in this pathology. Goldmann applanation tonometry remains the reference for intraocular pressure assessment even in corneas after penetrating keratoplasty. However, some promising alternatives have emerged, the most important of which are the Pascal dynamic contour tonometry, the Tono-Pen XL, the ocular response analyzer, and the iCare. All have advantages and disadvantages but have proved to be appropriate alternatives, especially in cases in which Goldmann applanation tonometry cannot be used.

Paradox of complex diversity: Challenges in the diagnosis and management of bacterial keratitis

Bacterial keratitis continues to be one of the leading causes of corneal blindness in the developed as well as the developing world, despite swift progress since the dawn of the "anti-biotic era". Although, we are expeditiously developing our understanding about the different causative organisms and associated pathology leading to keratitis, extensive gaps in knowledge continue to dampen the efforts for early and accurate diagnosis, and management in these patients, resulting in poor clinical outcomes. The ability of the causative bacteria to subdue the therapeutic challenge stems from their large genome encoding complex regulatory networks, variety of unique virulence factors, and rapid secretion of tissue damaging proteases and toxins. In this review article, we have provided an overview of the established classical diagnostic techniques and therapeutics for keratitis caused by various bacteria. We have extensively reported our recent in-roads through novel tools for accurate diagnosis of mono- and poly-bacterial corneal infections. Furthermore, we outlined the recent progress by our group and others in understanding the sub-cellular genomic changes that lead to antibiotic resistance in these organisms. Finally, we discussed in detail, the novel therapies and drug delivery systems in development for the efficacious management of bacterial keratitis.

Efficacy of conjunctival flap surgery for deep corneal ulcers

Aim: To evaluate the clinical efficacy of a selective, partial, pedicle conjunctival flap in the treatment of deep corneal ulcers with or without perforation, resistant to medical treatment.

Method: This interventional self-controlled retrospective study included 31 eyes of 31 patients with deep corneal ulcers who underwent conjunctival flap surgery in a tertiary eye care unit between 2017 and 2019. Of these, 9 eyes exhibited corneal perforation. The follow-up period was 12 months. The primary outcome measures were restoring ocular surface integrity and secondary outcome measures were improvement in visual acuity and postoperative complications encountered.

Results: Out of the total of 31 patients, 17 patients (55%) were males and 14 patients (45%) were females. The mean age was 56.03 ± 15.46 years. The mean disease duration was 64.10 ± 35.01 days, the mean diameter of the ulcer was 3.61 ± 1.02 mm and the mean depth of the ulcer was 70.65 ± 20.28% of the thickness of the cornea. The etiology was extensive and the corneal ulcers were categorized as infectious (12), noninfectious (16), and unknown (3). An anatomic cure was obtained in 29 (94%) of 31 eyes. Conjunctival flap surgery was unsuccessful in 2 eyes that required evisceration. The postoperative visual acuity (BCVA) improved in 13 (42%) of the 31 eyes, decreased in 9 eyes (29%) and remained unchanged in 9 eyes (29%). The most frequent complications after conjunctival flap surgery were pseudopterygium, cataract and corneal opacity and less frequent complications were glaucoma, astigmatism, flap retraction, corneal perforation and endophthalmitis.

Conclusions: Conjunctival flap surgery can successfully treat refractory deep corneal ulcers. It can restore ocular surface integrity and provide metabolic and mechanical support for corneal healing. Also, it can avoid emergency penetrating keratoplasty or create appropriate conditions for a future optic keratoplasty.