Rigid Gas Permeable Scleral Lenses Research Articles

Применение склеральных линз для коррекции посткератопластической аметропии

Purpose. Analysis of clinical and functional results of correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses. Material and methods. Clinical and functional results of the correction of postkeratoplastic ametropia (PA) with rigid gas-permeable scleral lenses (RGSL) were analyzed based on a comprehensive examination of 25 eyes (25 patients). Of these, there were 16 men and 9 women. The mean age of the patients was 40±9 years. Uncorrected visual acuity (UCVA) was 0.14±0.16, best corrected visual acuity (BCVA) with glasses was 0.44±0.25, the spherical refractive component was 1.37±2.58 D, the cylindrical refractive component was –4,75±1.68 D. The follow-up period was about 5 years. Results. After application of RGSL, all patients noted a significant improvement in visual acuity due to the correction of PA and an increase in the regularity of the corneal graft. There was a statistically significant increase in BCVA in RGSL up to 0.66±0.13 (p=0.0022), which remained stable throughout the entire observation period. BCVA in RGSL 0.5 and above was noted in 93% of the eyes. In all patients, after the selection of RGSL, a significant decrease in total corneal aberrations, including higher order ones, was noted. When calculating the cell density of the epithelium of the corneal graft on HRT III Cornea after 5 years of wearing RGSL, a decrease in the cell density of all layers of the epithelium was noted. The absence of endothelial cell density loss, clinically significant corneal graft edema, and reduction in the biomechanical properties of the corneal graft indicate the safety of long-term use of RGSL in patients after keratoplasty. Conclusion. Clinical and functional analysis of the correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses during 5 years of observation showed: higher rates of best corrected visual acuity compared to spectacle correction by an average of 0.22±0.05, a significant decrease in corneal aberrations, a decrease in the density of cells of all corneal graft epithelium layers, high optical efficiency, and safety of their use during the entire observation period. Key words: postkeratoplastic ametropia, rigid gas-permeable scleral lens, corneal graft

Comparative analysis of the correction of irregular postkeratoplastic astigmatism with scleral lenses and intrastromal ring implantation

Background. Many patients after penetrating keratoplasty (PK) experience induced postkeratoplastic astigmatism, which is often irregular and causes an increase in corneal aberrations that reduce visual acuity and quality. The aim of the study. To conduct a comparative analysis of the effect of rigid gas permeable scleral lenses and the MyoRing implantation method on clinical and functional parameters in patients with IPA. Material and methods. The clinical study included 60 patients (60 eyes). The age of patients with IPA was from 25 to 42 years. All patients underwent penetrating keratoplasty. All patients were divided into two groups depending on the method for irregular postkeratoplastic astigmatism correction. Group I included 30 patients (30 eyes) who were fitted with rigid gas permeable scleral lenses. Group II consisted of 30 patients (30 eyes) who underwent implantation of the MyoRing into a penetrating corneal graft. The observation period was 1 year. Results. After 12 months of observation, there was a greater increase in uncorrected visual acuity by an average of 3 lines, in corrected visual acuity – by 2 lines; a greater decrease in corneal aberrations in photo- (root mean square (RMS) of total aberrations (RMS total) by 0.30 ± 0.08 µm, RMS of higher order aberrations (RMS HOA) – by 1.01 ± 0.24 μm) and mesopic conditions (RMS total – by 0.33 ± 0.09 μm, RMS HOA – by 0.08 ± 0.03 μm) in patients wearing rigid gas permeable scleral lenses compared with patients after MyoRing implantation into a penetrating corneal graft. Conclusion. Patients of group I, wearing rigid gas permeable scleral lenses, showed a greater improvement in visual acuity and a decrease in corneal aberrations in photo- and mesopic conditions compared to the patients of group II (after MyoRing implantation) at a follow-up period of 12 months.

Contact lenses in dry eye disease and associated ocular surface disorders.

Dry eye disease (DED) is prevalent in all age groups and is known to cause chronic ocular discomfort and pain, and greatly affects the quality of life. Patients with ocular surface disease (OSD) may also have reduced tear secretion due to lacrimal gland damage, thus leading to aqueous deficient DED. Even with conventional management modalities such as lubricating eyedrops, topical corticosteroids, autologous serum eyedrops, or punctal plugs, many patients continue to suffer from debilitating symptoms. Contact lenses are increasingly being used in OSD providing surface hydration, protection from environmental insults, mechanical damage from abnormal lids, and as a modality for constant drug delivery to the ocular surface. This review describes the role of soft lenses and rigid gas-permeable scleral lenses in the management of DED associated with OSD. The efficacy of contact lenses, lens selection, and optimal lens fit are reviewed for specific indications.

Contact correction of postkeratoplastic ametropia in patients after deep anterior lamellar keratoplasty

Purpose. To conduct a clinical and functional analysis of contact correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses (RGPSL) in patients after deep anterior lamellar keratoplasty.Material and methods. Clinical and functional results of correction of postkeratoplastic ametropia with RGPSL were analyzed on the basis of a comprehensive examination of 35 eyes (35 patients) after deep anterior lamellar keratoplasty (DALK) performed for stage III keratoconus. The examination included patients who had low corrected visual acuity with spectacle correction and the corneal suture was removed 1 year or more after deep anterior lamellar keratoplasty. All patients underwent: autorefractokeratometry, visometry, biomicroscopy, computed keratotopography, aberrometry, endothelial cell density calculation, analysis of corneal graft biomechanical properties, optical coherence tomography of the corneal graft. The mean age of the patients was 29 ± 8 years. In all patients, RGPSL was selected on average 1.5 ± 0.85 years after DALK. All RGPSL were from OKVision (OKV-RGP Onefit Med, Canada). The follow-up period was 6 months.Results. The uncorrected visual acuity was 1.0 ± 1.18 LogMAR, the best corrected visual acuity (BCVA) with glasses was 0.5 ± 0.8 LogMAR, the spherical refractive component was 2.44 ± 2.12 D, the cylindrical refractive component was -6,25 ± 1.24 D. The average value of BCVA in RGPSL increased to 0.72 ± 0.14 (p = 0.0054). The obtained result remained stable during 6 months of observation. In the analysis of corneal aberrations measured with the OPD-Scan II device before and after 6 months after wearing of RGPSL was noted a statistically significant decrease in total corneal aberrations, including higher-order ones. After 6 months of observation, according to Confoscan-4 data was noted the decrease in the density of corneal graft endothelial cells from 2526 ± 332 to 2510 ± 302 cells/mm² (p = 0.0326) and it corresponded to physiological losses.Conclusions. Clinical and functional analysis of the correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses during 6 months of follow-up showed high optical efficiency and safety of their use during the entire observation period.

On the question of progressive hyperopia correction after radial keratotomy

Progressive hyperopia development in the long-term period after radial keratotomy (RC) is associated with not only surgical effects, but also individual biomechanical features of the fibrous tunic of the eye, its age-related changes, and hydrodynamic disturbances. When choosing a method of correction, one should take into account a number of features characteristic of this induced refractive disorder: instability and irregularity of refraction, coexisting presbyopia, and, in some cases, anisometropia. Correction of progressive hyperopia after RC can be achieved with eyeglasses, or contacts, or intraocular lenses depending on the subjective factor - the so-called patient adherence. The most effective in terms of functionality is contact correction with scleral rigid gas-permeable lenses, and in the presence of pronounced lens opacities - intraocular correction.

Influence of scleral lenses on visual acuity and aberrations in patients with irregular cornea

Purpose: To analyze changes of functional parame¬ters and aberrations before fitting and after using rigid gas-permeable scleral lenses (RGPSCL) in patients with irregular cornea. Material and methods. 21 patients (29 eyes) with irregular astigmatism of various etiology were enrolled in this study. The patients could not achieve good visual aсuity in glasses, standard soft or rigid corneal contact lenses. Complex ophthalmologic examination was per¬formed: autorefractometry, visometry, biomicroscopy, computer corneal topography, aberrometry on “OPD-Scan II” (“Nidek”, Japan) before fitting scleral lenses and during the period of their wearing. Results and discussion. The results demonstrat¬ed significant visual acuity improvement after RGP¬SCL fitting in all observed patients. UCVA amounted to 0.1±0.18, BCVA in glasses amounted to 0.4±0.26, BCVA in RGPSCL amounted to 0.7±0.1. An increase of best-corrected visual acuity in RGPSCL was statistically significant in patients after keratoplasty, after intra-stromal corneal ring segments (ICRS) implantation, af¬ter refractive laser surgery (RLS) and in cases of mixed astigmatism. We have found that the correction of ker¬atoconus with the use of RGPSCL resulted in a decrease of the root mean square value (RMS), measured in the 3 mm and 5 mm zones by 2.5 times and 4 times, re¬spectively. In patients wearing RGPSCL after kerato¬plasty, statistically significant decrease in RMS was observed in the 3 mm zone (by 3.85 times) and in the 5 mm zone (by 2.99 times). In patients wearing RGPSCL after implantation of intrastromal corneal ring segment (ICRS), RMS in the 3 mm zone decreased by 1.5 times. In patients wearing RGPSCL after refractive laser surgery (RLS) RMS was 2.5 times lower in the 3 mm zone and 2.8 times lower in the 5 mm zone. In case of mixed astigmatism correction with RGPSCL, RMS increased by 1.6 times in the 3 mm zone and practically did not change in the 5 mm zone. Conclusion. The results obtained demonstrated significant visual acuity improvement in all observed patients. The sub-lens-space filled with tear forms a unified “cornea-tear-scleral contact lens” optic system that corrects unevenness of cornea, decreases amount of high-order aberrations (HOA) and provides a clear stable vision.

Rigid gas permeable scleral lenses: There has to be a bearing surface somewhere

Rigid gas permeable scleral lenses: There has to be a bearing surface somewhere

Keratokonus – the killing application for most contact lenses is the prototypical job for sclerals

SummaryUse of blown glass shells, the precursors of scleral lenses, for management of keratoconus was first described in the late 1800's. Keratoconus has been a leading indication for scleral lenses throughout the history of the devices, both prior to and following the introduction of rigid gas permeable scleral lenses in 1983. Scleral lenses offer several benefits compared to corneal lenses for primary corneal ectasia. They do not require alignment with a highly irregular corneal surface, and are instead supported by the conjunctival tissue overlying the relatively regular sclera. They offer excellent comfort and lens stability. Scleral lenses do not touch the cornea, so may be less likely to lead to corneal epitheliopathy or scarring. Unlike corneal transplantation, scleral lenses can immediately provide improvement in the quality of vision, and are considerably less invasive. Furthermore, scleral lenses may provide improved ocular comfort for patients with concurrent keratoconus and atopic disease of the lids and adnexa. This presentation will review and summarize visual and ocular outcomes of scleral lens therapy for management of exposure keratopathy at the Mayo Clinic.

Advances in scleral lenses for refractive surgery complications.

The last two decades have brought advances in materials and manufacturing of large diameter rigid gas-permeable contact lenses, and a greater appreciation of the role of scleral lenses for therapeutic indications. The purpose of this review is to provide an update on the use of rigid gas-permeable scleral lenses in the management of patients with complications after refractive surgery. There are recent reports on clinical experience with specific scleral lens designs from single institutions in cohorts that include patients who have undergone refractive surgery. Typically, these are patients with 'irregular corneas' after radial keratotomy or LASER assisted in-situ keratomileusis, but patients with keratectasia, dry eye syndrome, and corneal neuralgia are also reported. Visual outcomes and wearing success rates are high in these reports, although outcomes for refractive surgery patients are not reported separately. Clinicians who encounter patients with complications after corneal refractive surgery should be aware of advances in scleral lenses. Scleral lenses are an alternative to surgical intervention in patients who might otherwise be considered poor contact lens candidates.

Scleral lens for ocular surface disease

Scleral rigid gas-permeable (RGP) lenses play an important and underappreciated role in the treatment of ocular surface disease. This review provides an update on scleral rigid gas-permeable lenses in the therapy of ocular surface disease (OSD). Several large cohort studies and case series have been published since 2008 that report on the use of scleral RGP lenses in the treatment of ocular surface disease as a sub-group of corneal disease, or in specific diseases such as Stevens-Johnson syndrome and ocular chronic graft-versushost disease. In addition, there are case reports detailing the treatment with scleral lenses in OSD of specific etiology such as herpes zoster, limbal stem cell deficiency or ocular cicatricial pemphigoid. Two case series were published showing innovative utility of scleral RGP lenses in the management of OSD after glaucoma surgery and for drug delivery for corneal neovascularization. Reports continue to emerge on the impact of scleral RGP lenses in the treatment of patients with ocular surface disease. Advances in lens design and fitting techniques make scleral RGP lenses a practical option for a rising number and variety of patients with corneal disease. Clinicians who treat patients with ocular surface disease should be aware of scleral RGP lenses as a method to treat OSD. J. Exp. Clin. Med., 2012; 29:S50-S54

Technological Advances Shaping Scleral Lenses: The Boston Ocular Surface Prosthesis in Patients with Glaucoma Tubes and Trabeculectomies

The Boston Ocular Surface Prosthesis (BOS-P) (Boston Foundation for Sight, Needham, MA) is a fluid-ventilated rigid gas-permeable scleral lens that is utilized for the treatment of irregular corneal astigmatism and severe ocular surface disease. Recent reports have highlighted the utility of the BOS-P as a therapeutic device in cases of persistent epithelial defects, corneal neovascularization, ocular graft versus host disease, and exposure keratopathy. Patients with significant cornea disease might also have glaucoma, and those who have undergone glaucoma surgery, which typically disrupts the limbus, present a challenge when fitting the BOS-P. This report describes five patients with a history of both corneal disease and glaucoma surgery who were successfully fitted with the BOS-P.

Update on scleral lenses

Scleral rigid gas-permeable lenses play an important and underappreciated role in the treatment of corneal disease. This review provides an update on scleral rigid gas-permeable lenses for the visual rehabilitation of ectasia and irregular astigmatism, and an update on scleral rigid gas-permeable lenses in the therapy of ocular surface disease. Several series and one case report present advances in the treatment of ocular surface disease with scleral rigid gas-permeable lenses. In addition, there are two reports describing one center's consecutive case experience using modern scleral lens design, predominantly in patients with ectasia and postkeratoplasty astigmatism. Finally, a comprehensive article reviewing the history and principles behind current scleral rigid gas-permeable lenses, with particular attention to the use of scleral rigid gas-permeable lenses in the management of ocular surface disorders was published. Clinicians who treat patients with ocular surface disease should be aware of scleral rigid gas-permeable lenses as a therapeutic option for their patients. Advances in lens design make scleral rigid gas-permeable lenses a practical option for an increasing number and variety of patients with corneal disease.

The Boston Scleral Lens in the treatment of pediatric patients

To report the use of a custom-designed, fluid-ventilated, gas-permeable scleral lens in the treatment of patients under 13 years of age. We retrospectively reviewed the medical records of all patients under 13 years of age who were fitted with the Boston Scleral Lens at the Boston Foundation for Sight from January 1996 through June 2006. Age, sex, ophthalmic diagnosis, systemic diagnosis, prior surgical intervention, complications, lens fit and wearing failures, and duration of lens use are reported. Boston Scleral Lenses were fitted in 47 eyes of 31 patients referred after failure of conventional therapy. Patients ranged in age from 7 months to 12.92 years (mean, 7.75 years) at time of fitting. There were 16 girls and 15 boys in this group. The mean duration of documented scleral lens use was 24 months (range, 0-85 months). A broad range of refractive and ocular surface disorders was treated with this modality, with the vast majority of patients having ocular surface disease (27/31, 87%) rather than refractive disorders (4/31, 13%). Congenital corneal anesthesia syndromes and Stevens-Johnson syndrome each accounted for over one-third of the patients. The Boston Scleral Lens is a custom-designed, fluid-ventilated, rigid gas-permeable scleral lens that vaults the cornea retaining a pool of oxygenated artificial tears over the corneal surface. The Boston Scleral Lens is a treatment option, after failure of conventional therapy, for a broad range of ocular surface and refractive disorders in the pediatric age group. Pediatric ophthalmologists should be aware of this treatment modality, particularly in the management of severe ocular surface disease.

100+ Dk: does thickness make much difference?

Sealed impression scleral lenses were used to investigate if, with a material over MOM, reducing the lens thickness produced less adverse effects upon corneal metabolism. Three subjects wore sealed rigid gas permeable scleral lenses (115Dk) of different thicknesses. The central corneal thickness was measured pre- and post-wear. The results showed that the corneal swelling induced by the 0.30mm thick lens and the 0.15mm thick lens was not significantly different. Thus, when using a material with a permeability of over 100Dk, the centre thickness of the lens does not effect corneal metabolism as regards corneal swelling for lens substances below 0.30mm