Treatment of persistent corneal epithelial defect with extended wear of a fluid-ventilated gas-permeable scleral contact lens

Infectious and Noninfectious Corneal Ulcers in Ocular Graft-Versus-Host Disease: Epidemiology, Clinical Characteristics, and Outcomes

PURPOSE

To evaluate the incidence, clinical characteristics, microbiological profile, and therapeutic outcomes of corneal ulcers in individuals with chronic ocular graft-vs-host disease (coGVHD).

DESIGN

Retrospective clinical cohort study.

METHODS

Review of individuals diagnosed with coGVHD following hematopoietic stem cell transplantation (HSCT) who were seen at the Bascom Palmer Eye Institute between May 2010 and November 2021. Baseline demographics, clinical characteristics, microbiological profile, risk factors for corneal ulceration, and treatment outcomes were collected. Etiology was deemed infectious in individuals with a positive culture or appropriate clinical scenario (presence of stromal infiltrate or hypopyon); otherwise, ulcers were presumed to be noninfectious. Treatment success was defined as reepithelialization with infiltrate resolution, and treatment failure as progression to corneal perforation or keratoplasty. Kaplan-Meier survival analysis estimated the incidence of ulceration. Cox regression analyses examined demographic and risk factors. Infectious and noninfectious ulcer groups were compared using 2-way independent t tests, 1-way analysis of variances, and χ2 tests, as appropriate.

RESULTS

173 individuals were included (53.7±14.4 years old; 59.0% male). Thirty-three individuals developed an ulcer 74.5±54.3 months after HSCT, with estimated 5- and 10-year incidences of 14% and 30%, respectively. Twenty-two (66.6%) ulcers were deemed infectious (15 microbiologically confirmed, 7 clinically) and 11 (33.3%) were deemed noninfectious. Risk factors for corneal ulceration included Black race (hazards ratio [HR] 2.89, 95% CI 1.30-6.42, P < .01), previous ocular surgery (HR 9.16, 95% CI 3.86-21.72, P < .01), eyelid margin abnormalities (HR 3.44, 95% CI 1.69-6.99, P < .01), and topical steroid use (HR 2.74, 95% CI 1.33-5.62, P < .01). Conversely, contact lens use reduced the risk of corneal ulceration (HR 0.29, 95% CI 0.13-0.66, P < .01). Infectious ulcers had a significantly higher frequency of treatment failure than noninfectious ulcers (57.1% vs 20.0%, P = .04).

CONCLUSION

Corneal ulceration is a potential complication of coGVHD, with several clinical features identified as risk factors. Infectious ulcers had worse outcomes than noninfectious ulcers.

A Review of Contact Lens-Induced Limbal Stem Cell Deficiency

Limbal stem cell deficiency (LSCD) is a pathologic condition caused by the dysfunction and destruction of stem cells, stem cell precursors and limbal cell niche in the corneal epithelium, leading to severe conjunctivalization of the cornea. Etiologies for LSCD span from congenital (aniridia), traumatic (chemical or thermal injuries), autoimmune (Stevens-Johnson syndrome) and iatrogenic disease to contact lens (CL) wear. Of these, CL wear is the least understood and is often a subclinical cause of LSCD. Even with recent advances in LSCD research, limitations persist in establishing the pathogenesis and treatment guidelines for CL-induced LSCD. A literature search was conducted to include original articles containing patients with CL-induced LSCD. This review will critically discuss the complex pathophysiology behind CL-induced LSCD, the underlying risk factors and epidemiology of the disease as well as methods to obtain a diagnosis. Various treatment options will be reviewed based on proposed treatment strategies.

New developments in the management of persistent corneal epithelial defects

A persistent epithelial defect (PED) is a corneal epithelial defect that failed to heal after 2weeks. It is a condition that carries much morbidity, and our understanding of PED remains poor, with current treatment methods often having unsatisfactory outcomes. With PEDs becoming more prevalent, more efforts are required to establish reliable treatment modalities. Our reviews describe the causes of PEDs and the different approaches developed to manage them, as well as their associated limitations. Emphasis is placed on understanding various advances in the development of new treatment modalities. We have also described a case of a woman with a background of graft-versus-host disease on long-term topical corticosteroids who developed complicated PED involving both eyes. The current approach to managing PEDs generally involves exclusion of an active infection, followed by treatment modalities that aim to encourage corneal epithelial healing. Success rates, however, remain far from desirable, as treatment remains challenging due to multiple underlying etiologies. In summary, advances in the development of new therapies may be able to facilitate progress in the understanding and treatment of PED.

Long-Term Benefits of Tear Exchangeable Limbal-Rigid Contact Lens Wear Therapy in Stevens-Johnson Syndrome Cases

OBJECTIVES

To evaluate the long-term benefits of tear-exchangeable, limbal-rigid contact lens (CL) wear therapy in patients with Stevens-Johnson syndrome (SJS)-associated ocular sequelae.

METHODS

This retrospective study evaluated 50 eyes of 41 SJS patients (15 men and 26 women) who underwent limbal-rigid CL wear therapy for more than 2 years post fitting. Ocular sequelae (i.e., conjunctival hyperemia, corneal neovascularization, and upper tarsus scarring) before fitting and at 3 months, 6 months, 12 months, and annually after initiating CL wear therapy were evaluated and then graded on a severity score (range: 0-3, maximum score: 3). Moreover, visual acuity (VA) at immediately post initiating CL wear therapy was evaluated.

RESULTS

The mean follow-up period was 4.3±1.1 years. Compared with before fitting, the mean conjunctival hyperemia score improved from 1.14 to 0.86 at 3 months of CL wear therapy ( P <0.01) and was maintained thereafter; the mean corneal neovascularization score improved from 2.10 to 1.98 at 3 months of CL wear therapy, with no deterioration of the score observed in all cases at the final follow-up examination, and mean VA (log of minimum angle of resolution) improved from 1.60 to 1.04 at immediately post initiating CL wear therapy ( P <0.01).

CONCLUSIONS

Limbal-rigid CL wear therapy can provide long-term ocular surface stabilization and improved VA in SJS patients.

Therapeutic contact lenses for the treatment of corneal and ocular surface diseases: advances in extended and targeted drug delivery

The eye is one of the most important organs in the human body providing critical information on the environment. Many corneal diseases can lead to vision loss affecting the lives of people around the world. Ophthalmic drug delivery has always been a major challenge in the medical sciences. Since traditional methods are less efficient (∼ 5%) at delivering drugs to ocular tissues, contact lenses have generated growing interest in ocular drug delivery due to their potential to enhance drug bioavailability in ocular tissues. The main techniques used to achieve sustained release are discussed in this review, including soaking in drug solutions, incorporating drug into multilayered contact lenses, use of vitamin E barriers, molecular imprinting, nanoparticles, micelles and liposomes. The most clinically relevant results on different eye pathologies are presented. In addition, this review summarizes the benefits of contact lenses over eye drops, strategies for incorporating drugs into lenses to achieve sustained release, results of in vitro and in vivo studies, and the recent advances in the commercialization of therapeutic contact lenses for allergic conjunctivitis.

Scleral contact lenses for optimal visual recovery in a case of severe acid burn with total lagophthalmos

Chemical injuries can severely damage the ocular surface. We present the case of a man in his 40s with severe periocular chemical injury with total lid loss and severe exposure keratopathy. He sustained burns to 45% of his body surface area and needed tracheostomy and multiple full-thickness skin grafts. Both eyes required surgery, Boston type 1 keratoprosthesis and penetrating keratoplasty for the right and left eye, respectively. There was melting in the right eye and a persistent epithelial defect in the left eye. Eventually, we suggested 18 mm diameter scleral contact lenses for both eyes to aid in ocular surface stabilisation. His best corrected visual acuity improved significantly with the scleral lenses to 20/100 and 20/320 in the right and left eyes, respectively. This case demonstrates that scleral lenses can treat the complications of exposure keratopathy and can improve vision. Therefore, they may be considered for rehabilitation of the ocular surface in eyes with severe chemical periocular injuries.

Comparison of the efficacy of topical insulin with autologous serum eye drops in persistent epithelial defects of the cornea

PURPOSE

To investigate the effect of topical insulin on epithelization in persistent epithelial defects (PED) refractory to usual treatment compared to autologous serum.

DESIGN

Retrospective, consecutive case-control series.

METHODS

The charts of 61 consecutive patients with PED treated with topical insulin (case group) and 23 treated with autologous serum (control group) were reviewed. Primary efficacy end points were the percentage of patients in which epithelization was achieved, as well as the rate and time until epithelization. Secondary efficacy point was need for amniotic membrane transplantation (AMT) or other surgeries.

RESULTS

Mean time between PED diagnosis and start of topical insulin was 22.7 ± 18.5 days (range 13-115) and the mean area was 14.8 ± 16.2 mm² (range 1.1-70.6). In the control group, mean time was 27.9 ± 16.8 days, mean epithelial defect area being 18.6 ± 15.0 mm² (range 1.7-52.9). No differences in baseline characteristics were found between groups (p > 0.05). Epithelization was achieved in 51 patients (84%) on insulin and 11 patients (48%) on autologous serum (p = 0.002). In those patients, mean time until reepithelization was 32.6 ± 28.3 days (range 4-124) in the insulin group and 82.6 ± 82.4 days (range 13-231) in the autologous serum group (p = 0.011). The need for AMT was significantly lower in the insulin group (p = 0.005). PED recurrence was higher in patients treated on autologous serum (43%) compared with insulin (11%) (p = 0.002).

CONCLUSIONS

Topical insulin is an effective treatment and safely promotes healing of PED. In our series, topical insulin presented better epithelization outcomes than autologous serum and could thus be considered as a first-line treatment.

Microbial Keratitis Associated With Penetrating Keratoplasty and Scleral Lens Wear: A Case Series

OBJECTIVES

To report on microbial keratitis (MK) in three scleral lens (SL) wearers who had undergone penetrating keratoplasty (PKP).

METHODS

This retrospective case series describes 3 cases of MK in patients who wore SLs after PKP.

RESULTS

All three patients wore SLs for visual rehabilitation for corneal irregularity induced by PKP; all three also had concurrent ocular surface disease (keratoconjunctivitis sicca and corneal exposure). Cultures identified the causative organism in two patients, and septated hyphae suggestive of fungal infection were identified in tissue removed during therapeutic PKP in the third patient. All three patients were receiving either topical or systemic immunosuppressive therapy before the infection developed.

CONCLUSIONS

Scleral lenses are often used to manage complex ocular disease, which can make it difficult to determine the precise cause of complications that arise after wearing the lenses. Multiple factors, including SL wear, may have contributed to the initial development of MK in the three patients in this case series. Patients who wear SLs after PKP should be monitored closely.

Scleral Lens Thickness and Corneal Edema Under Closed Eye Conditions

OBJECTIVES

To examine the relationship between central lens thickness and central corneal edema during short-term closed eye scleral lens wear.

METHODS

Nine participants (mean age 30 years) with normal corneas wore scleral lenses (Dk 141) under closed eye conditions on separate days with nominal center thicknesses of 150, 300, 600, and 1,200 μm. Epithelial, stromal, and total corneal edema were measured using high-resolution optical coherence tomography immediately after lens application and after 90 min of wear, before lens removal. Data were corrected for variations in initial fluid reservoir thickness and compared with predictions from theoretical modeling of overnight scleral lens wear.

RESULTS

Scleral lens-induced central corneal edema was primarily stromal in nature. The mean±standard error of corrected total corneal edema was 4.31%±0.32%, 4.55%±0.42%, 4.92%±0.50%, and 4.83%±0.22% for the 150-, 300-, 600-, and 1,200-μm lenses, respectively. No significant differences in the corrected total corneal edema were observed across all thickness groups (P=0.20). Theoretical modeling of overnight scleral lens wear seemed to overestimate the relative increase in central corneal edema as a function of decreasing lens Dk/t for values lower than 25.

CONCLUSION

The magnitude of scleral lens-induced central corneal edema during short-term closed eye lens wear did not vary significantly with increasing central lens thickness. Theoretical modeling of overnight closed eye scleral lens wear seems to overestimate the effect of increasing lens thickness.

Diphtheroids as Corneal Pathogens in Chronic Ocular Surface Disease in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis

PURPOSE

To characterize diphtheroid corneal infections in eyes in the chronic phase of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN).

METHODS

Observational case series.

RESULTS

Four eyes of 3 patients were included in this review. Each eye presented with persistent corneal epithelial defect with corneal thinning in the chronic phase of SJS/TEN. None of the epithelial defects were associated with stromal infiltration. The corneas were cultured at the time of workup of persistent epithelial defect (3 eyes) or at time of tectonic penetrating keratoplasty after perforation (1 eye). Cultures yielded abundant growth of Corynebacterium spp., including Corynebacterium jeikeium (n = 2), Corynebacterium glucuronolyticum (n = 1), and a multidrug-resistant Corynebacterium striatum isolate (n = 1). The ocular surface was stabilized with surgical intervention (1 eye) or with introduction of fortified topical antibiotic based on laboratory identification and susceptibility testing of the isolated organisms (3 eyes). Numerous risk factors for microbial keratitis were present in all 4 eyes.

CONCLUSIONS

In eyes with a persistent corneal epithelial defect in the chronic phase of SJS/TEN, even in the absence of an infiltrate, corneal culture should be undertaken. Recognition and treatment of Corynebacterium spp. as opportunistic pathogens may lead to favorable outcomes in cases of clinically sterile ulceration during the chronic phase of SJS/TEN.

Current and future therapies for persistent corneal epithelial defects and neurotrophic keratopathy

PURPOSE OF REVIEW

The corneal epithelium is a crucial barrier against pathogens, and when disrupted in the setting of certain underlying risk factors such as neurotrophic keratopathy (NK), may result in persistent epithelial defects (PEDs) of the cornea. Management is challenging and may require a variety of different approaches ranging from conservative medical therapy to surgical intervention. The purpose of this review is to provide an update on current and potential future therapeutic options for PEDs and NK.

RECENT FINDINGS

Recent research has yielded promising results for numerous novel therapies aimed at treating PEDs. Many of these attempt to stimulate healing at the cellular level, via signaling of corneal epithelial differentiation, migration, and proliferation. Considerable advances have also been made regarding medical and surgical promotion of corneal re-innervation and restoration of corneal sensitivity to directly address the underlying NK condition.

SUMMARY

Together with the current well established therapeutic options available for PEDs and NK, growing research on newer alternatives suggest increasing potential for both more effective and more convenient therapies for these difficult situations.

CLEAR - Medical use of contact lenses

The medical use of contact lenses is a solution for many complex ocular conditions, including high refractive error, irregular astigmatism, primary and secondary corneal ectasia, disfiguring disease, and ocular surface disease. The development of highly oxygen permeable soft and rigid materials has extended the suitability of contact lenses for such applications. There is consistent evidence that bandage soft contact lenses, particularly silicone hydrogel lenses, improve epithelial healing and reduce pain in persistent epithelial defects, after trauma or surgery, and in corneal dystrophies. Drug delivery applications of contact lens hold promise for improving topical therapy. Modern scleral lens practice has achieved great success for both visual rehabilitation and therapeutic applications, including those requiring retention of a tear reservoir or protection from an adverse environment. This report offers a practical and relevant summary of the current evidence for the medical use of contact lenses for all eye care professionals including optometrists, ophthalmologists, opticians, and orthoptists. Topics covered include indications for use in both acute and chronic conditions, lens selection, patient selection, wear and care regimens, and recommended aftercare schedules. Prevention, presentation, and management of complications of medical use are reviewed.

CLEAR - Scleral lenses

Scleral lenses were the first type of contact lens, developed in the late nineteenth century to restore vision and protect the ocular surface. With the advent of rigid corneal lenses in the middle of the twentieth century and soft lenses in the 1970's, the use of scleral lenses diminished; in recent times there has been a resurgence in their use driven by advances in manufacturing and ocular imaging technology. Scleral lenses are often the only viable form of contact lens wear across a range of clinical indications and can potentially delay the need for corneal surgery. This report provides a brief historical review of scleral lenses and a detailed account of contemporary scleral lens practice including common indications and recommended terminology. Recent research on ocular surface shape is presented, in addition to a comprehensive account of modern scleral lens fitting and on-eye evaluation. A range of optical and physiological challenges associated with scleral lenses are presented, including options for the clinical management of a range of ocular conditions. Future applications which take advantage of the stability of scleral lenses are also discussed. In summary, this report presents evidence-based recommendations to optimise patient outcomes in modern scleral lens practice.

Scleral Lens Use in Neurotrophic Keratopathy: A Review of Current Concepts and Practice

OBJECTIVE

Neurotrophic keratopathy (NK) is a rare corneal condition characterized by epitheliopathy, which is associated with reduced or absent corneal sensation. The main goal of treatment of this condition is the preservation of ocular surface integrity. Contact lenses provide a nonsurgical and reversible option to provide the necessary corneal protection. The purpose of this review was to summarize the available literature regarding the use of contact lenses in the management of NK, with particular emphasis on the use of scleral lenses.

METHODS

Literature related to both soft and scleral contact lens use as treatment options for NK was reviewed.

RESULTS

As of yet, randomized clinical trials have compared neither the efficacy of contact lens therapy for NK to other therapeutic alternatives nor outcomes of therapy with different contact lens modalities. However, clinical case reports and limited case series have suggested that scleral lenses may be a safe and effective treatment option for NK at any stage of the disease, preserving epithelial integrity and even improving visual function in patients with this condition.

CONCLUSIONS

Scleral lenses may be effective in reducing the need for surgical intervention and improving the quality of life in patients with NK.

Prevalence of Persistent Corneal Epithelial Defects in Chronic Ocular Graft-Versus-Host Disease

PURPOSE

To establish the prevalence, clinical characteristics, and risk factors for persistent corneal epithelial defects (PED) in patients with chronic ocular graft-versus-host disease (oGVHD) and to determine visual outcomes after healing.

DESIGN

Retrospective cohort study.

METHODS

A chart review was conducted of patients in whom chronic oGVHD was diagnosed between January 2011 and December 2018 and their demographic and clinical characteristics were collected. Data were analyzed to determine prevalence of PED, and multivariate logistic regression was performed to determine the risk factors associated with it.

RESULTS

A total of 405 patients at a mean age of 60 ± 13 years in whom chronic oGVHD was diagnosed; 58% were men. The prevalence of PED was 8.1%. The median time for PED development after hematopoietic stem cell transplantation was approximately 24 months. Median time to PED resolution was 4.5 weeks after starting therapy. The mean best-corrected visual acuity declined by 2 lines post-PED resolution. The prevalence rates of corneal ulcer and perforation were 6.2% and 4.0%, respectively, over 8 years. Logistic regression analysis, used to determine factors associated with PED, showed diabetes (P = .006), limbal stem cell deficiency (LSCD) (P = .02), filamentary keratitis (P = .02), subconjunctival fibrosis (P = .02), and a higher National Institutes of Health (NIH) oGVHD score (P = .01) were significant risk factors for PED development.

CONCLUSIONS

The study found the prevalence rate of PED, corneal ulceration, and corneal perforation in chronic oGVHD to be 8.1%, 6.2%, and 4%, respectively. Analysis showed that oGVHD patients with diabetes, LSCD, filamentary keratitis, subconjunctival fibrosis, and a high NIH score were at higher risk of developing severe corneal disease.

Topical insulin for refractory persistent corneal epithelial defects

PURPOSE

To evaluate insulin eye drops for persistent epithelial defects (PEDs) that are refractory to usual treatment in clinical practice and to analyze how it may improve epithelization.

METHODS

A prospective non-randomized hospital-based study was performed. Patients with PEDs that were refractory to conventional treatment were treated with insulin eye drops four times a day. Patients' demographics, PED etiology, concomitant treatments, and comorbidities were reviewed. The rate of PED closure and epithelial healing time were considered the primary outcome measures.

RESULTS

21 patients were treated with insulin drops (12 females and 9 males; mean age 72.2 years). Mean PED area before treatment was 17.6 ± 16.5 mm² (median 13.2; range 3.9-70.6). PED comorbidities included seven eyes with infectious keratitis (33%), five eyes with calcium keratopathy (24%), ocular surgery on three eyes (14%), three eyes with lagophthalmos (14%), two eyes with bullous keratopathy (10%), and one patient with herpetic eye disease (5%). The eyes of 17 patients (81%) with refractory PEDs had reepithelized and four patients (19%) had still presented an epithelial defect by the end of the study follow-up period, although it had decreased in size. In patients where PED closure was achieved, mean time until reepithelization was 34.8 ± 29.9 days (median 23; range 7-114). In the remaining patients, a mean area reduction of 91.5% was achieved for the PEDs.

CONCLUSION

Topical insulin can promote and accelerate corneal reepithelization of refractory PEDs. It also offers many other advantages, including excellent tolerance, availability, and cost-effectiveness.

Treatment of Severe Infectious Keratitis With Scleral Contact Lenses as a Reservoir of Moxifloxacin 0.5

PURPOSE

To report the outcomes of using scleral contact lenses as antibiotic reservoirs as a therapeutic approach in a case series of severe infectious keratitis and to discuss the clinical potential.

METHODS

This was a prospective consecutive case series study of 12 eyes treated for infectious keratitis at the "Conde de Valenciana" Institute of Ophthalmology. A scleral lens (SL) filled with 0.5% moxifloxacin was used as a reservoir and replaced every 24 hours until epithelization was complete or the culture report and/or antibiogram demonstrated either a microorganism not susceptible to or resistant to moxifloxacin.

RESULTS

The study included 12 eyes of 12 patients (7 women; 58.33%; average age of 63 ± 20.11 years). All patients completed at least 1 month of follow-up. Patients had a diagnosis of infectious keratitis, and the SL was fitted on initial consultation. Of the 12 eyes, 7 had culture-positive bacterial infection, 2 eyes were mycotic, and 3 eyes had no culture growth. In 3 eyes, SL was discontinued because of the lack of response (one eye) and to the presence of mycotic infection (2 eyes). All infections resolved favorably at the final follow-up.

CONCLUSIONS

The use of SLs could be an alternative for antibiotic impregnation and treatment of infectious keratitis. No complications or side effects were observed related to the use of the scleral contact lens as a reservoir for the antibiotic. This treatment modality could offer a comfortable treatment for the patient, ensuring good impregnation and maintenance of antibiotic concentrations during the 24-hour wear periods.

Anatomical and physiological considerations in scleral lens wear: Conjunctiva and sclera

While scleral lenses have been fitted using diagnostic lenses or impression moulding techniques for over a century, recent advances in anterior segment imaging such as optical coherence tomography and corneo-scleral profilometry have significantly improved the current understanding of the anatomy of the anterior eye including the morphometry of the conjunctiva, sclera, and corneo-scleral junction, as well as the ocular surface shape and elevation. These technological advances in ocular imaging along with continual improvements and innovations in scleral lens design and manufacturing have led to a global increase in scleral lens prescribing. This review provides a comprehensive overview of the conjunctiva and sclera in the context of modern scleral lens practice, including anatomical variations in healthy and diseased eyes, the physiological impact of scleral lens wear, potential fitting challenges, and current approaches to lens modifications in order to minimise lens-induced complications and adverse ocular effects. Specific topics requiring further research are also discussed.

Approaches toward enhancing survival probability following deep anterior lamellar keratoplasty

The greatest advantage of deep anterior lamellar keratoplasty over full-thickness corneal transplantation is the elimination of graft failure caused by endothelial rejection. Despite this advantage, a deep anterior lamellar keratoplasty graft can fail because of several factors, such as complications related to the donor-recipient interface, graft epithelial abnormalities, graft vascularization, stromal graft rejection, and recurrence of herpetic keratitis. Increased deep anterior lamellar keratoplasty graft survival is mainly built upon optimization of the ocular surface to provide a hospitable environment for the graft. Any predisposing factors for graft epithelial abnormalities, corneal neovascularization, and preexisting vernal keratoconjunctivitis should be identified and treated preoperatively. Prompt recognition and appropriate treatment of interface-related complications and stromal graft rejection usually result in good anatomic outcomes, with no detrimental effects on vision.

Miniscleral lenses in the treatment of patients with dry eye syndrome (first own experience)

Background. Scleral lenses, due to their benefits, hold a specific position among all types of contact lenses. Some years ago, they began to be used successfully not only for the correction of complex types of refractive errors, when other types of correction failed to achieve satisfactory visual function and visual rehabilitation of patients, but also as a therapeutic system in the management of ocular surface disease. Purpose. To evaluate the efficacy of rigid gas permeable miniscleral contact lenses as a therapeutic system in the management of patients with dry eye syndrome by filling the space under the lens with a non-preserved sodium hyaluronate solution. Materials and methods. In the study, 7 patients (11 eyes) with keratectasias after corneal surgery and concomitant dry eye syndrome were included. In the treatment and rehabilitation of these patients, miniscleral contact lenses were used during daytime with additional filling of the space under the lens with a non-preserved sodium hyaluronate solution. Results. As a criterion of the effectiveness of miniscleral contact lens use for therapeutic purposes, along with a significant increase in visual function in patients with complex corneal pathology, the elimination of discomfort due to restoration of the corneal epithelium integrity and improvement of their quality of life is considered.

Hyaluronic Acid Combined with Serum Rich in Growth Factors in Corneal Epithelial Defects

The aim of this study is to assess if an adhesive biopolymer, sodium hyaluronate (NaHA), has synergistic effects with s-PRGF (a serum derived from plasma rich in growth factors and a blood derivative that has already shown efficacy in corneal epithelial wound healing), to reduce time of healing or posology. In vitro proliferation and migration studies, both in human corneal epithelial (HCE) cells and in rabbit primary corneal epithelial (RPCE) cultures, were carried out. In addition, we performed studies of corneal wound healing in vivo in rabbits treated with s-PRGF, NaHA, or the combination of both. We performed immunohistochemistry techniques (CK3, CK15, Ki67, ß4 integrin, ZO-1, α-SMA) in rabbit corneas 7 and 30 days after a surgically induced epithelial defect. In vitro results show that the combination of NaHA and s-PRGF offers the worst proliferation rates in both HCE and RPCE cells. Addition of NaHA to s-PRGF diminishes the re-epithelializing capability of s-PRGF. In vivo, all treatments, given twice a day, showed equivalent efficacy in corneal epithelial healing. We conclude that the combined use of s-PRGF and HaNA as an adhesive biopolymer does not improve the efficacy of s-PRGF alone in the wound healing of corneal epithelial defects.

Wound healing in the eye: Therapeutic prospects

In order to maintain a smooth optical surface the corneal epithelium has to continuously renew itself so as to maintain its function as a barrier to fluctuating external surroundings and various environmental insults. After trauma, the cornea typically re-epithelializes promptly thereby minimizing the risk of infection, opacification or perforation. A persistent epithelial defect (PED) is usually referred to as a non-healing epithelial lesion after approximately two weeks of treatment with standard therapies to no avail. They occur following exposure to toxic agents, mechanical injury, and ocular surface infections and are associated with significant clinical morbidity in patients, resulting in discomfort or visual loss. In the case of deeper corneal injury and corneal pathology the wound healing cascade can also extend to the corneal stroma, the layer below the epithelium. Although significant progress has been made in recent years, pharmaco-therapeutic agents that promote corneal healing remain limited. This article serves as a review of current standard therapies, recently introduced alternative therapies gaining in popularity, and a look into the newest developments into ocular wound healing.

Serum from plasma rich in growth factors regenerates rabbit corneas by promoting cell proliferation, migration, differentiation, adhesion and limbal stemness

PURPOSE

To evaluate the regenerating potential and the mechanisms through which the autologous serum derived from plasma rich in growth factors (s-PRGF) favours corneal wound healing in vitro and in vivo.

METHODS

We compared the effect of various concentrations of s-PRGF versus fetal bovine serum (FBS) and control treatment in rabbit primary corneal epithelial and stromal cells and wounded rabbit corneas. Cell proliferation was measured using an enzymatic colorimetric assay. In vitro and in vivo wound-healing progression was assessed by image-analysis software. Migration and invasion were evaluated using transfilter assays. Histological structure was analysed in stained sections. Protein expression was evaluated by immunohistochemistry.

RESULTS

s-PRGF promoted the robust proliferation of epithelial cultures at any concentration, similar to FBS. Likewise, s-PRGF and FBS produced similar re-epithelialization rates in in vitro wound-healing assays. In vivo, s-PRGF treatment accelerated corneal wound healing in comparison with control treatment. This difference was significant only for 100% s-PRGF treatment in our healthy rabbit model. Histological analysis confirmed normal epithelialization in all cases. Immunohistochemistry showed a higher expression of cytokeratins 3/76 and 15, zonula occludens-1 and alpha-smooth muscle actin proteins as a function of s-PRGF concentration. Notably, keratocyte density in the anterior third of the stroma increased with increase in s-PRGF concentration, suggesting an in vivo chemotactic effect of s-PRGF on keratocytes that was further confirmed in vitro.

CONCLUSION

s-PRGF promotes proliferation and migration and influences limbal stemness, adhesion and fibrosis during corneal healing.

An analysis of anterior scleral shape and its role in the design and fitting of scleral contact lenses

PURPOSE

The purpose of this study was to evaluate the shape of the anterior sclera by measuring the sagittal height and corneoscleral transition angles in the four cardinal and four oblique segments of the eye.

MATERIALS AND METHODS

In this study, 78 normal eyes of 39 subjects were evaluated. The sagittal height, corneoscleral angle and scleral angle were measured at three chord lengths (10.0mm, 12.8mm and 15.0mm) in all eight segments of the anterior eye using optical coherence tomography (Zeiss Visante AS-OCT). Scleral toricity was calculated for each eye, defined as the greatest sagittal height difference found between two perpendicular meridians.

RESULTS

At a 12.8mm chord length, the shape of the anterior eye was found to be nearly rotationally symmetric, and at a chord of 15.0mm the shape became more asymmetric. The average sagittal heights of the eight segments at a 12.8mm chord ranged from 2890μm to 2940μm; at a 15.0mm chord they ranged from 3680μm to 3790μm. The average scleral angles at a 15.0mm chord ranged from 35.17° to 38.82°. Significant differences between opposing segments were found in the sagittal height and scleral angle measurements at a chord of 15.0mm (sagittal height p≤0.0021; scleral angle p≤0.0105). The nasal measurements revealed flatter scleral angles and concave corneoscleral transitions, whereas temporal scleral angles were steeper, with tangential or convex corneoscleral transitions.

CONCLUSION

These findings are important to consider when designing and fitting contact lenses that rest beyond the boundaries of the limbus, such as scleral lenses.

Comparison of the influence of corneo-scleral and scleral lenses on ocular surface and tear film metrics in a presbyopic population

PURPOSE

To assess and compare the effect of the corneo-scleral lenses (C-ScL) and scleral lenses (ScL) on tear film parameters and central corneal thickness (CCT) in healthy presbyopic subjects.

METHODS

Thirty subjects wore two contact lenses (CLs), randomly assigned, of neutral power, but of different diameters, 12.7mm (C-ScL) and 18mm (ScL) and being equal in the others parameters: material (HS100) and centre thickness (0.29mm). At baseline, 20min after insertion and at 8h, the tear meniscus area (TMA) and CCT was measured (with optical coherence tomography) as well as tear osmolarity.

RESULTS

TMA revealed statistical differences for both lenses at 20min (p<0.001), and also at 8h (p=0.003), being greater for the C-ScL. CCT showed statistical differences for both lenses at 20min (p=0.002), and also at 8h (p=0.001), being lower for the C-ScL. Osmolarity did not reveal statistical differences at 20min (p=0.29), while it was statistically different at 8h (p=0.03), being lower for the C-ScL.

CONCLUSIONS

C-ScL lead to a lesser reduction in the TMA and a lower induced hypoxic stress than the ScL. Osmolarity levels remained within normal values across the day with no clinical difference between lenses. Both designs can represent a good optical platform for correcting presbyopia as well as protecting the ocular surface by vaulting the cornea.

Role of mini-scleral lens in mucous membrane pemphigoid

This study aims to report the use of mini-scleral contact lens in the management of mucous membrane pemphigoid (MMP) with persistent epithelial defects. A 68-year-old male with a history of ocular pain and declining visual acuity was referred to our clinic with a diagnosis of MMP. His corrected distance visual acuity (CDVA) was 20/200 in the right eye and 20/100 in the left eye. Despite being on lubricants, topical steroids and intravenous cyclophosphamide, the patient developed persistent corneal epithelial defects in both eyes. He was then given a trial of mini-scleral lenses. Within 4 weeks, corneal epithelial defects healed, and at 6 months, the CDVA had improved to 20/50 in the right eye and 20/40 in the left eye. By improving the corneal surface integrity and visual function, mini-scleral lenses can play a role in the visual rehabilitation of patients with MMP.

Comparing the effects of two different contact lenses on corneal re-epithelialization after corneal collagen cross-linking

OBJECTIVE

To investigate whether keratoconus (KC) patients who applied the corneal collagen cross-linking (CXL) and two different contact lens (CL) showed any differences in complaints and findings following the CXL.

METHODS

This prospective, comparative, double-blind clinical study involved 60 eyes of 60 patients (38 female and 22 male). At the end of the CXL procedure, CL (Balafilcon A) was inserted in 29 patients (Group-1) while CL with different material content (Hioxifilcon A) designed for therapeutic/bandage purposes were inserted in 31 patients (Group-2).

RESULTS

On the 1^st and 3^th day after the CXL, there were no statistically significant differences between the groups in terms of the postoperative symptoms. On the 3^th day after the CXL, all cases of both two groups were found to complete the corneal re-epithelialization. There was more PE ratio in the patients who had allergic conjunctivitis.

CONCLUSIONS

With the use of Balafilcon A and Hioxifilcon A lens materials, KC patients who underwent the CXL were found to have similar symptoms and clinical findings after the CXL. However, epithelial staining and PE were observed more in KC cases accompanied by allergic conjunctivitis.

Dry Eye Treatment Based on Contact Lens Drug Delivery: A Review

Dry eye disease affects a substantial segment of the word population with increasing frequency. It is a multifactorial disease of the ocular surface and tear film, which causes ocular discomfort, visual disturbances, and tear instability with potential damage to the cornea and conjunctiva. Because of its multifactorial etiology, the use of different pharmacological treatment for dry eye treatment has been proposed, which include anti-inflammatory molecules, lubricants or comfort agents, and secretagogues. However, in some cases these pharmacological approaches only relieve symptoms temporarily, and consequently, eye care professionals continue to have difficulties managing dry eye. To improve pharmacological therapy that allows a more efficient and long-term action, effective ocular drug delivery of the currently available drugs for dry eye treatment is required. Contact lenses are emerging as alternative ophthalmic drugs delivery systems that provide an increased residence time of the drug at the eye, thus leading to enhanced bioavailability and more convenient and efficacious therapy. In this article, we reviewed the different techniques used to prepare contact lens-based drug delivery systems and focused on articles that describe the delivery of compounds for dry eye treatment through contact lenses.

Dysfunctional tear syndrome: dry eye disease and associated tear film disorders - new strategies for diagnosis and treatment

Dysfunctional tear syndrome (DTS) is a common and complex condition affecting the ocular surface. The health and normal functioning of the ocular surface is dependent on a stable and sufficient tear film. Clinician awareness of conditions affecting the ocular surface has increased in recent years because of expanded research and the publication of diagnosis and treatment guidelines pertaining to disorders resulting in DTS, including the Delphi panel treatment recommendations for DTS (2006), the International Dry Eye Workshop (DEWS) (2007), the Meibomian Gland Dysfunction (MGD) Workshop (2011), and the updated Preferred Practice Pattern guidelines from the American Academy of Ophthalmology pertaining to dry eye and blepharitis (2013). Since the publication of the existing guidelines, new diagnostic techniques and treatment options that provide an opportunity for better management of patients have become available. Clinicians are now able to access a wealth of information that can help them obtain a differential diagnosis and treatment approach for patients presenting with DTS. This review provides a practical and directed approach to the diagnosis and treatment of patients with DTS, emphasizing treatment that is tailored to the specific disease subtype as well as the severity of the condition.

[Effectiveness of soft contact lenses in severe keratoconjunctivitis sicca treated with local immunosuppressive therapy]

AIM

To study the effectiveness of soft contact lenses in severe keratoconjunctivitis sicca (KCS) treated with local immunosuppressive therapy.

MATERIAL AND METHODS

We have examined 41 patients (60 eyes) with severe KCS, including 3 men (4 eyes) and 38 women (56 eyes) aged from 27 to 76 years. Group 1 consisted of 22 persons (30 eyes) who were prescribed cyclosporine А 0.05% instillations 2 times daily, artificial tears, and soft contact lenses. Group 2 consisted of 19 patients (30 eyes) who received instillations of cyclosporine А 0.05% 2 times daily for no less than 6 months and artificial tears. Apart from the standard ophthalmic examination, the assessment included Schirmer's test, tear break-up time test, fluorescein eye stain test, tear osmometry, Heidelberg tomography of the cornea, optical coherence tomography of the anterior segment with meniscometry, impression cytology of the conjunctiva, tear pH measurement, plating of the content of the conjunctival cavity for its microflora, measurement of the width of the palpebral fissure, and calculation of the ocular surface disease index (OSDI). Treatment outcomes were evaluated at 1, 3, 6, and 12 months.

RESULTS

In group 1, complete re-epithelialization of the cornea (confirmed by all the methods used) was achieved rather shortly, in 1-3 months, while in group 2 - in 6 months.

CONCLUSION

The use of soft contact lenses in addition to cyclosporine A instillation therapy promotes restoration of corneal and conjunctival epithelium, reduces treatment time, and improves quality of life for patients, thus, proving itself a safe and effective treatment of autoimmune KCS.

Contact Lens-induced Limbal Stem Cell Deficiency

Limbal stem cell deficiency (LSCD) is a pathologic condition caused by the dysfunction and/or destruction of stem cell precursors of the corneal epithelium, typified clinically by corneal conjunctivalization. The purpose of this review is to critically discuss a less well-known cause of limbal stem cell disease: contact lens (CL) wear. A literature search was conducted to include original articles containing patients with CL-induced LSCD. This review describes epidemiology, diagnostic strategies, pathogenesis, differential diagnosis, and treatment modalities for this condition.

Preclinical assessment of scleral lens as a reservoir-based ocular therapeutic system

PURPOSE

Bacterial keratitis is a sight threatening infection of the cornea which remains one of the most important potential complications of contact lens use. If the corneal ulcer is small, peripheral with no impending perforation present, intensive monotherapy with fluoroquinolones could be used. Therefore, a study was conducted with the objective to provide pharmacological data of the intra-ocular diffusion after administration of Ofloxacin using a scleral lens reservoir, as well as an evaluation of surface tolerability in rabbits.

MATERIALS AND METHODS

Samples of corneas, aqueous humor and vitreous were collected to measure the drug levels of Ofloxacin using High Performance Liquid Chromatography. The corneas were examined by electron microscopy scanning and the eyeballs by light polarizing microscopy in order to evaluate surface tolerability.

RESULTS

Ofloxacin levels found in the aqueous humor and cornea were higher than those previously reported. The mean Ofloxacin corneal levels exceeded the MIC (Minimum Inhibitory Concentration) for which 90% of isolates are indicated for all bacteria implicated in keratitis.

CONCLUSION

To our knowledge, this is the first preclinical study assessing local tolerance and intra-ocular diffusion of Ofloxacin after administration using a scleral lens reservoir.

The Use of the Esclera Scleral Contact Lens in the Treatment of Moderate to Severe Dry Eye Disease

PURPOSE

To evaluate the efficacy of the Esclera scleral contact lens (SCL) treatment and its impact on clinical testing for moderate to severe dry eye disease (DED).

DESIGN

Prospective interventional case series.

METHODS

A total of 41 eyes from 25 patients with moderate to severe DED were evaluated for the Esclera SCL treatment. Best-corrected visual acuity (BCVA), tear osmolarity, the Schirmer I test, tear film breakup time (TBUT), corneal and conjunctival staining, meibomian grading, and Ocular Surface Disease Index and SF-36v2 questionnaires were assessed before and after the SCL treatment. These values were compared to assess the real benefit of using SCL as a treatment for DED.

RESULTS

Forty-one eyes from 25 patients were fitted with SCL for management of DED. The underlying diseases were Stevens-Johnson syndrome (22 eyes), Sjogren syndrome (11 eyes), graft-vs-host disease (2 eyes), dry eye after keratomileusis in situ (2 eyes), and undifferentiated ocular surface disease (4 eyes). BCVA improved from 0.703 ± 0.55 logMAR with habitual correction to 0.406 ± 0.43 logMAR with SCL (P < .001). There was a significant decrease in tear osmolarity values (338.1 ± 27.1 to 314.25 ± 38.8 mOsm/L, P < .001) and van Bijsterveld scores (3.63 ± 2.33 to 2.63 ± 2.46 grade, P = .015) between the baseline and 12 months after SCL wear. There were also significant improvements in dry eye symptoms and quality of life as assessed by the OSDI and SF-36v2 questionnaires (both with P < .001).

CONCLUSIONS

The Esclera SCL treatment had a positive impact on tear osmolarity and van Bijsterveld score, as well as an improvement in the patients' BCVA, dry eye symptoms, and quality of life.

Stevens-Johnson syndrome: The role of an ophthalmologist

Stevens-Johnson syndrome (SJS) is an acute blistering disease of the skin and mucous membranes. Acute SJS leads to the acute inflammation of the ocular surface and chronic conjunctivitis. If not properly treated, it causes chronic cicatricial conjunctivitis and cicatricial lid margin abnormalities. Persistent inflammation and ulceration of the ocular surface with cicatricial complications of the lids leads to chronic ocular sequelae, ocular surface damage, and corneal scarring. The destruction of the glands that secrete the tear film leads to a severe form of dry eye that makes the management of chronic SJS difficult. The option that is routinely used for corneal visual rehabilitation, keratoplasty, is best avoided in such cases. We describe the management strategies that are most effective during the acute and chronic stages of SJS. Although treatments for acute SJS involve immunosuppressive and immunomodulatory therapies, amniotic membrane transplantation is also useful. The options for visual rehabilitation in patients with chronic SJS are undergoing radical change. We describe the existing literature regarding the management of SJS and highlight recent advances in the management of this disorder.