Scleral lens solution

Contact lenses are classified on the basis of the bearing zone area as Corneal, Corneo-scleral and Scleral lenses. Scleral lenses are large in diameter (18 - 23mm) and have a bearing completely on sclera. It has a large tear reservoir which helps in epithelial protection, enhances epithelial healing and enhances vision. Scleral lenses have evolved over the years in the material, design and fitting parameters. The earlier lenses were made of polymethacrylate, with poor oxygen permeability and caused corneal hypoxia. Later, came in the fenestrated scleral lenses. Although they had the advantage of minimal lens suction, they caused corneal exposure to air. The modern scleral contact lenses are made of material with high oxygen permeability and are non-fenestrated. These are called the rigid gas permeable scleral contact lenses. The scleral contact lenses are available in two types. They could be Preformed lenses or Impression technique designed. The Impression technique type, wherein a mold is prepared after impression, are no more in use. The Preformed scleral lenses come with a set of lenses with variable diameters and fitting parameters. Amongst the various parameters used in fitting of scleral contact lenses, the measurement of sagittal height is the most critical for a good fit. The sagittal height measurement has been made accurate with the advent of optical coherence tomography. The lens could be designed as spherical, toric or bifocal. Most common lens design used is spherical scleral contact lenses. Toric scleral lenses could be front toric, back toric or bitoric and used for patients with irregular astigmatism and corneal ectasia. Boston scleral lenses are one of the most popular scleral contact lenses. A highly customized lens for the patient is designed using the topographic guided software and gives the scope of changing lens fitting parameters instantly. The Boston scleral lenses find the maximum application on patients with end stage ocular surface disorders. The growing popularity of scleral contact lenses is due to the encouraging results in various indications. These can be broadly divided into indications for vision improvement (primary ectasia-includes conditions such as keratoconus, keratoglobus and pellucid marginal degeneration and the secondary ectasia group includes post-refractive surgery, including post-laser assisted in-situ keratomileusis, post-laser assisted epithelial keratoplasty, postphotorefractive keratectomy and postradial keratotomy) and indications for corneal protection (Steven Johnson syndrome, graft versus host disease, ocular cicatricial pemphigoid, neurotrophic corneal disease, atopic keratoconjunctivitis, Sjögren's syndrome, persistent epithelial corneal defects). It is important for every ophthalmologist to be aware of the option of treating patients with ocular surface disorders and corneal ectasia with scleral contact lenses. The article describes the various aspects of scleral contact lenses –classification, historical milestones in development, various modern scleral lens designs and fitting parameters. Published literature, indication and results of rigid gas permeable scleral contact lenses is also discussed.

Clinical outcomes of scleral Misa lenses for visual rehabilitation in patients with pellucid marginal degeneration.

Eye injuries in children are one of the leading causes of blindness and early disability associated with developmental delay. Scleral rigid contact lenses represent an effective method of vision correction in patients with corneal irregularities. Scleral lenses improve visual acuity and reduce aberrations by providing a more regular anterior corneal surface with the aqueous layer forming between the lens and the cornea. AIM: To study the specifics of correction with personalized scleral rigid contact lenses in vision rehabilitation in pediatric patients with injury-related corneal scarring. RESULTS: The paper presents with case reports in which personalized scleral rigid contact lenses were required to be fitted for children with injury-related corneal scarring. The ophthalmological examination included visometry, autorefractometry, biomicroscopy, Scheimpflug imaging with Galilei G6, optical coherence tomography of the cornea with Anterion, and aberrometry with OPD-Scan III. In all cases, the scleral lenses were fitted with a personalized approach. Highly positive refractory and vision outcomes were obtained. All patients were more than satisfied with the functional outcomes, tolerability, and adaptation to the lenses. CONCLUSION: Scleral lenses may be used in pediatric patients with injury-related corneal scarring in order to improve vision functions, reduce aberrations, and restore binocular vision. In most cases, this method of contact correction is the only one to achieve better vision acuity in children with injury-related corneal scarring.

Objective: To describe vision-correction benefits of gas-permeable scleral contact lenses in the management of corneal opacities. Materials and Methods:Fourteen patients (15 eyes) with corneal opacities were referred initially for corneal graft.Butdue to the lack of grafts, we proposed scleral lenses for vision correction as a temporary solution. Results: The most common indication for lenses fitting was keratoconus with opacity in patients who had to stop wearing other types of corneal lenses and referred for corneal graft (8 eyes). Other indications included interstitial keratitis, herpetic keratitis, ocular scars from Stevens-Johnson syndrome and acid burn. Mean follow-up period was 14 months (2-24). The opacity was central in 9 patients and paracentral in 5. Mean use time of scleral lenses was 12 hours per day. Average logMAR visual acuity without correction and with lenseswas 1,7 and 0,3 respectively.A gain of three or more Snellen lines was observed in 92,85% of eyes.The scleral lenses were well tolerated in all patients.One patient had problems with lenses manipulation.The scleral lenses had no effect on the evolution of the opacities. Conclusion:Gas permeable scleral lenses provide successful visual solutions for corneal opacity when corneal grafts are not available.

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

Predicting estimates of oxygen transmissibility for scleral lenses

Lid-Related Keratopathy in Stevens-Johnson Syndrome: Natural Course and Impact of Therapeutic Interventions in Children and Adults

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.

Scleral rigid contact lenses efficiently correct the vision of patients with irregular corneas. Purpose. To study the features of contact correction and visual rehabilitation of patients with irregular corneal surface using individual scleral rigid contact lenses. Results. Three clinical cases of successfully selected rigid individual scleral lenses for patients with an irregular corneal surface that appeared after a penetrating keratoplasty, implantation of intrastromal corneal segments, and eye injury. The expected refractive result was achieved; high tolerance and good adaptation to lenses was revealed. Conclusion. Scleral RCL can be successfully used in patients with irregular cornea to improve visual acuity, reduce the number of aberrations, restore binocular vision and social adaptation.

Keratoconus is a degenerative and progressive corneal disease that occurs bilaterally and asymmetrically. The cornea's thinning and protrusion are its defining features. Vision is decreased as a result of these changes. This case report demonstrates how a severe keratoconus patient was managed with scleral contact lenses, thereby effectively precluding the need for surgery. Despite the challenges of this condition, scleral lenses work well. Here, I describe the case of a 34-year-old male who came to our center with a known history of severe keratoconus. His uncorrected visual acuity was counting fingers in each eye, with minimal improvement from eyeglasses. He had routine exams, and I confirmed that he was a good candidate for wearing scleral lenses. I successfully fitted this patient with mini-scleral lenses in both eyes. The fitting was optimal, which allowed the patient to achieve a 20/30 visual acuity in each eye, emphasizing the positive impact of this non-surgical approach. This case study intends to document the success of managing severe keratoconus using scleral contact lenses.

Relevance Keratoconus (KC) is a chronic non-inflammatory dystrophic disease of the cornea, accompanied by its cone-shaped "bulging" in the central zone and thinning in the apex zone [1, 2]. It has also been proven that as the clinical stage of KC is expressed, significant changes occur in the precorneal tear film and cornea, which causes the appearance of dry eye syndrome (DES) [3, 4]. Objective Evaluation of changes in the state of the precorneal tear film in KC in combination with DES while wearing scleral contact lenses (SCL). Material and methods A total of 31 patients (62 eyes) were examined, who were fitted with individual SCLs for stabilized non-operated KC of various stages. A comprehensive assessment of the tear film condition included the following methods: anterior segment biomicroscopy using vital dyes, functional tests, OCT meniscometry, as well as the OSDI questionnaire and an oral survey. The studies were conducted before, after 1 and 3 months while wearing the lenses. Results Before fitting the SCL, the absence of staining of the ocular surface was recorded in 29% of cases, after 3 months - in 94% of cases. The data from the functional tests conducted before fitting the SCL showed a decrease in the stability of the precorneal tear film. As the period of wearing the lenses increased, the tear film breakup time increased significantly: after one month of wearing by 12%, after 3 months - by 27% of the initial values. An oral survey showed complete adaptation to the SCL and comfort when wearing it in 87% of cases. The following effects were noted while wearing the SCL: a decrease in the degree of epitheliopathy, an increase in the functional test results, which indicates the restoration of the normal function of the tear film. Conclusion The results of the study confirm the effectiveness of the use of SCL in the protection of the ocular surface in patients with keratoconus in combination with signs of dry eye syndrome. Keywords: keratoconus; dry eye syndrome; scleral rigid gas-permeable lenses; tear film

Scleral contact lenses in the management of pellucid marginal degeneration.

BackgroundTo determine the extent of scleral lens fitting worldwide and to characterise the associated patient demographics.MethodsSurvey forms were sent to contact lens fitters around the world, every year for 20 consecutive years (2000 to 2019). Practitioners were asked to record data relating to the first 10 contact lens fits or refits performed after receiving the survey. Data were analysed for those countries reporting ≥ 1,000 contact lens fits during this period.ResultsA total of 369,209 contact lens fits were recorded from 40 eligible countries, comprising 2,309 scleral lens fits and 366,900 other (non‐scleral) lens fits. Overall scleral lenses represented 0.76 per cent of all contact lens fits with significant differences between countries (p < 0.0001), ranging from no fits in six countries: Hungary, Indonesia, Iran, Korea, Malaysia and Singapore, to 5.9 per cent in Switzerland. There has been an increase in scleral lens fitting over the survey period (p < 0.0001), with the rate of fits increasing from negligible (< 0.50 per cent) before 2006 and then increasing from 2011 onward (p < 0.0001). Scleral lenses were fit to older patients (38.5 ± 15.0-years) compared to other lenses (31.4 ± 13.7-years) (p < 0.0001), this age disparity increasing over the survey period (p < 0.0001) and were more likely to be males (scleral lens fits 53 per cent, non‐scleral lenses 33 per cent, p < 0.0001). The increase in scleral lens fits is commensurate with the increase in related publications in the peer‐reviewed literature over the same period (p < 0.05, r2 = 0.82).ConclusionScleral lens use has increased since 2011 with these specialised lenses more likely to be fitted to males and older patients than non‐scleral lenses.

Scleral lenses are being prescribed for the management of corneal irregularity, uncomplicated refractive error, and ocular surface disease. There are many potential therapeutic uses of scleral lenses in addition to providing similar benefits as corneal gas permeable lenses. Scleral contact lenses are a valuable therapeutic tool for patients with ocular surface disease as these lenses protect the ocular surface, provide continuous corneal hydration while providing optimal visual correction, and are often used in conjunction with other therapies.

Facial burns involving the periorbital region may lead to cicatricial ectropion and lagophthalmos, causing severe exposure keratopathy and eventually blindness if uncorrected. In these patients, it is critical to provide aesthetic and functional surgical correction to protect the ocular surface from chronic desiccation in addition to visual rehabilitation. Conventional methods may not be sufficient to provide visual rehabilitation in complex cases. Scleral lenses can be a multipurpose alternative for these patients. Herein, we present the challenging case of a patient who developed cicatricial lagophthalmos and exposure keratopathy after facial transplantation due to gasoline burns and received a scleral contact lens for visual rehabilitation.