Objective: This case report aims to explore the use of scleral lenses for the treatment of ocular and visual complications in an adult patient presenting with post-LASIK (Laser-Assisted in situ Keratomileusis) ectasia in both eyes with cross-linking in the right eye and Intrastromal Corneal Ring Segments (ICRS; IN- tacs, Addition Technology, Fremont, California) in the left eye.

Methods: Following a comprehensive eye exam and specific testing for contact lens fitting, scleral lenses were fitted with success in both eyes and dispensed. Due to progressive fibrosis and neovascularization of the inferior ICRS in the left eye, the inferior ICRS was removed and scleral lenses were refit with success.

Results: Prescribed scleral lenses helped the patient achieve optimal visual correction (20/20) as well as ocular protection of the cornea.

Conclusion: Post-LASIK ectasia is a common finding among contact lens specialists today. When ICRS surgery is involved, the fitting of contact lenses may become more challenging. Scleral lenses offer a unique way of addressing many issues raised in this case report such as corneal neovascularization and ectasia. This lens modality may be considered for any other case involving irregular corneal curvature following surgery and reduced visual acuity.

Key Words: Ectasia, ICRS, scleral lenses, neovascularization

Introduction: In the summer of 2013, patient JV, a 38 year-old Hispanic male, was referred by a cornea specialist for a contact lens evaluation for the treatment of fluctuating and unstable vision in both eyes. He had undergone a LASIK (Laser-Assisted in situ Keratomileusis) procedure in 2001 and was then diagnosed with post-LASIK ectasia in both eyes for which he underwent cross-linking in the right eye and Intrastromal Corneal Ring Segments (ICRS; IN- tacs, Addition Technology, Fremont, California) surgery in the left eye 4 weeks and 2 months, respectively, prior to his initial presentation. Scleral lenses were ordered for the patient and significantly improved the vision, both objectively and more so subjectively. A successful fit was obtained on the right eye and the lens was dispensed. On the left eye, however, an adequate fit could not be obtained because there was progressive fibrovascular growth over the inferior temporal ICRS with lens touch and resulting fluorescein staining at every visit despite consequent steepening of the lens. Because the ICRS continued to protrude forwards and push on the scleral lens, the patient was referred back to the cornea specialist for evaluation. The latter agreed with the assessment and discussed the recurrent inflammation and potential infection due to the ICRS and planned to remove the inferior segment in the near future. Earlier this year, when the inferior segment was removed, the patient returned for a new contact lens fitting of the left eye. At this time, the patient is very satisfied with both the vision and comfort he has with the scleral lenses. Although he does have some residual neovascularization in the lower cornea, the lens provides an adequate vault over the surface and has succeeded in maintaining the corneal integrity.

Case Report: J.V., a 38 year-old Hispanic male presented to the Global Vision Rehabilitation Center for a contact lens fitting and evaluation. He was referred by a cornea specialist for poor and unstable vision in both eyes and difficulty driving at night due to halos and starbursts around lights. A review of his ocular history revealed LASIK in both eyes in 2001, ICRS surgery 2 months prior in the left eye and a cross-linking procedure in the right eye 4 weeks prior to this initial presentation. He was also wearing a PROKERA lens 3 weeks prior to presentationfor 4-5 days over his right eye following the cross-linking. He had no history of glaucoma or trauma and was not using any eye drops. He had no history of ocular disease in his family. He had not been diagnosed with any medical problems, was not taking any medications and had no allergies to drugs. Entering Acuities measured 20/40- in the right eye and 20/30 in the left eye with spectacle correction. His refraction measured OD: +2.25 -4.50 x 080 and OS: +2.75 -5.00 x 105. With this correction his acuities were 20/30 and 20/25, respectively, however the patient reported significant distortion of the letters. His pupils were equal, round and reactive to direct and consensual illumination and there was no afferent papillary defect in either eye. Confrontational visual fields were full to finger counting in both eyes and extra ocular motility was full in both eyes. Slit lamp examination revealed Intacs segments in place 2 mm above and below the pupil in the left eye with crystallized deposits around the ring segments. He had superficial stromal vascularization extending to and arborizing along the inferior ring segment at 3:00 with mild underlying haze. The patient had clean lids and lashes, white and quiet conjunctivas, flat irides and clear lenses OD, OS. There were no proptosis or lid abnormalities in either eye. Intraocular pressures by Goldmann applanation tonometry measured 13 mm Hg OU at 11:09 am using one drop 0.5% proparacaine hydrochloride ophthalmic solution. Upon dilated fundus examination (using one drop 1% tropicamide and 2.5% Phenylephrine OU), the cup to disc ratios were found to be 0.2 OD, OS. The neuroretinalrims were healthy and pink in both eyes. The maculae were clear and flat in both eyes and retinal vasculature was of normal course and caliber. There were no breaks in the retinal periphery. There was a flat nevus just superior to the arcade in the right eye, which was approximately 2/3 of a disc diameter.

After the glasses were prescribed, contact lenses were strongly recommended as the primary treatment for the ectactic corneas in both eyes with vascularized Intacs in the left eye. In this condition, the ocular surface must be protected to minimize the risk of erosion; contact lenses help maintain constant lubrication of the corneal surface, which allows for its restoration. A soft bandage does not provide a good outcome for visual correction on a highly irregular cornea. Small diameter rigid gas permeable (RGP) lenses can provide a better alternative to improve visual acuity but do not protect the ocular surface. In fact, these lenses can increase mechanical stress on an already altered cornea in this case. One of the ways to resolve this issue could be to consider a piggy-back system, which implies fitting a high oxygen permeability soft lens carrier on top of which a high permeability RGP lens is fitted. In that way, the soft carrier aims to protect the cornea while the RGP restores visual acuity. Another solution includes the implementation of hybrid lenses. These consist of a gas permeable rigid center surrounded by a silicone hydrogel soft skirt. In fitting this lens, the skirt is designed to lift the rigid center off the corneal surface so that it never has to interact with it. However, there have been some reported cases of warpage with these lenses.1 In addition, most of, if not all of the hybrid lenses do not offer enough oxygen permeability to maintain ocular health in the presence of a compromised cornea.1 Large diameter RGP lenses can also be considered. These designs have become more and more popular and are available in several options: a corneo-scleral lens (12.5 mm to 15 mm), supported partly by the cornea and partly by the sclera; a mini-scleral lens (15 mm to 18 mm) vaulting the cornea, supported by the fluid layer and the conjunctiva; or a larger scleral lens (18 mm to 25 mm) with the same fitting philosophy as the mini-scleral lens but with different parameters.2 They are fitted in a way to vault the cornea. They maintain a constant reservoir of fluid between the lens and the cornea to ensure that it remains lubricated. More over, this fluid layer also compensates for the surface irregularities, leading to improved visual acuity. This modality can provide the comfort of a soft lens with the optical quality of a gas permeable lens. In that way, large diameter RGP lens designs currently available are considered the best option to provide health benefits and increased comfort compared to smaller corneal RGP and, in this case, soft lenses. In the case of post-LASIK ectasia followed by cross-linking in one eye and ICRS in the other, in order to determine which type of large diameter RGP lens to use, any touch on the cornea should be avoided. Corneo-scleral lenses are contraindicated because a small portion of the cornea supports most of the weight of the lens. This may result in a stress to the tissue that could cause a corneal epithelial defect and/or generate scarring. Mini-scleral lenses represent an improved option, where cornea-lens touch is absent with a limited amount of fluid layer. In addition, they are smaller than the large scleral lenses and are therefore easier to handle and less intimidating for patients to insert into their eyes.2

The Jupiter lens was chosen initially with the following parameters: OD base curve: 43.05 D (7.84 mm), diameter: 16.60 mm, power -3.00 with a reverse geometry curve. Using the VisanteTM Anterior segment OCT, it was determined that there was excessive (300 microns) apical clearance between the back of the lens and the front surface of the cornea. The base curve was the flattened to 41.01 D (8.23 mm), diameter: 16.60 mm, power -1.00, over-refraction: +0.25 Visual acuity: 20/20. For the left eye, an initial base curve of 41.98 D (8.04 mm) was chosen and also determined to be too steep and was then flattened to 39.02 D (8.65 mm).The diameter was 16.60 mm and the power +1.00. An over-refraction of +0.50 was found with a visual acuity of 20/20. When adequate apical clearance was confirmed (150 – 200 microns) in both eyes (Figure 2), the lenses were ordered with the following parameters:

OD: diameter: 16.60 mm, base curve 41.00 D (8.23 mm) reverse curve, power -0.75

OS: diameter: 16.60 mm, base curve 39.00 D (8.65 mm) reverse curve, power +1.50.

Figure 2: Visante TM Anterior Segment images of the right (a) and left (b) eyes fitted adequately with a scleral lens. Note 150 – 200 microns of apical clearance between the corneal surface and back surface of the scleral lens. Not the Intacs represented by empty spaces in the left eye using enhanced high resolution imaging.

When the patient returned 2 days later for dispensing of the lens, anterior segment examination revealed identical findings to the previous visit. Both lenses provided adequate apical clearance, no blanching or vascular compression of the conjunctival vessels, visual acuity of 20/20 in both eyes and patient comfort in both eyes. Following appropriate training, the patient proved to be proficient with both insertion and removal of the lenses. RGP cleaner and conditioning solution (Boston™) were recommended. Non-preserved 0.9% NaCl inhalation solution was prescribed to fill the lens before insertion.

When the patient returned for follow-up 2 days later, the vision continued to be 20/20 in both eyes, however, the patient reported mild discomfort in the left eye, especially after lens removal. Using the VisanteTM Anterior segment OCT to assess lens clearance, the right eye was acceptable with a clearance of 150 µm. Conversely; the left eye had adequate clearance centrally of 100-110 µm but minimal touch over the superior ring segment. The tissue outgrowth over the inferior ring segment was more pronounced than the last visit with lens touch at this location. (Figure 3) When the left lens was removed, and fluorescein sodium instilled in the left eye, mild diffuse punctate epithelial erosions could be appreciated and there was positive staining at 4:00 over the inferior ring segment.

Figure 3. Visante Anterior Segment OCT enhanced high resolution imaging of the left eye showing outward growth of the cornea around the inferior ICRS toward the back surface of the lens with minimal clearance in that area. Note the adequate clearance in the rest of the cornea.

In order to adequately vault over the outgrowth of tissue inferiorly and try to reverse the staining, an 18.20 mm lens was selected with a base curve of 39.99 D (8.44 mm) with power: plano. Until the new lenses were dispensed, left lens wear was discontinued. At the dispensing visit, slit lamp examination of the left eye showed improvement of corneal integrity over the inferior ring segment from 3:00-6:00. While the right eye continued to have adequate apical clearance, some bearing was appreciated over the superior ring segment at 119° in the left eye. The patient was then scheduled to return in 1 week to monitor the left eye.

When the patient returned, he reported good vision and comfort in the right eye but continued to complain of mild discomfort in the left eye with lens wear and removal, though improved from the last visit. The visual acuity was stable as was the integrity of the right cornea. After slit lamp examination of the left eye, the patient was noted to have improvement and almost complete resolution of the previous punctate epithelial erosions and irritation over the inferior ring segment. The mild discomfort experienced by the patient was attributed to a larger diameter lens in the left eye and therefore increased lens awareness. The patient was educated on lens awareness and that adequate adaptation time would be needed in order to tolerate the lenses. The patient was then scheduled for follow-up in 1 month. At this visit, the patient reported pain after lens removal in the left eye. Slit lamp and VisanteTM Anterior segment OCT examination both showed the inferior corneal ring segment pushing anteriorly at 6:00 against the scleral lens (Figure 4) with positive staining in this area of the cornea. Lens wear was discontinued, Tobradex was prescribed every hour and the patient was to return the following day. The next day, the patient reported improvement but still had positive staining in the same area of the cornea. Tobradex ointment was prescribed every 2 hours in the left eye on the first day and every 4 hours in the left eye on the second day.

Figure 4. Visante Anterior Segment OCT enhanced anterior segment imaging of the left eye showing outward growth of the cornea around the inferior ICRS toward the back surface of the lens with minimal clearance in that area. Note the adequate clearance in the rest of the cornea.

Three days later, at the follow-up, the staining had mostly resolved. Because the fibrovascular growth around the inferior corneal ring segment seemed to be progressing, the patient was referred for evaluation to a cornea specialist at the Bascom Palmer Eye Institute. The latter agreed with the prior assessment of fibrosis or infiltration of the inferior ring segment with outward protrusion in addition to neovascularization in the lower half of the cornea. He discussed with the patient the recurrent inflammation and potential infection due to the Intacs and decided to proceed with removal of the inferior ICRS. Antibiotics were continued and cultures obtained for the left eye.

Two months later the inferior corneal ring was explanted. Cultures and pathology were negative and the patient was prescribed PredForte 6 times a day and Vigamox 4 times a day. The steroid drops were progressively tapered and at the final follow-up with the surgeon, the latter reported that the cornea had healed nicely in the area of explantation with no staining. The antibiotic drop was discontinued and PreForte was maintained at 4 times a day for 1 month and then slowly tapered afterwards. The patient was then referred back to the Global Vision Rehabilitation Center for a new contact lens fitting. A new scleral lens was fit on the left eye. For this lens, a diameter of 20.60 mm was chosen in order to completely vault over the cornea, the limbus and perilimbal bulbar conjunctiva. A base curve of 8.39 mm and plano power was chosen. When the lens was dispensed, the superior corneal ring segment was touching the back of the lens, so the latter was steepened by 60µm. The patient is now wearing a 20.60 mm diameter lens with a base curve of 8.23 mm, reverse curve and a power of -1.50. The vision continues to be 20/20 in both eyes with no distortion. There is adequate apical clearance and comfort in both eyes. (Figure 5) Although the patient continues to have neovascularization on the inferior portion of the cornea in the left eye, what was thought to have been the insult was removed; the patient is expected to improve and is being monitored closely.

Figure 5. Visante Anterior Segment OCT enhanced high resolution imaging of the left eye showing 150 – 200 microns of apical clearance. Note the absence of inferior ICR and mild scarring in the area of explantation.

Differential Diagnosis:

Ring segment Extrusion

The most common cause of ICRS explantation; 48.2% according to a study by Ferrer and associates.3 This is caused by the superficial part of the corneal stromathinning over time, causing the ring segment to protrude forward leading to an epithelial breakdown. The latter is a necessary finding in order to make a diagnosis of ring segment extrusion.3In most cases, extrusion is accompanied by melting; vascularization also occurs in some cases.3The patient discussed in this case had corneal staining, indicating an epithelial break. However the cause of the irritation was not stromal thinning but by the superficial cornea protruding forward and rubbing on the scleral lens. This is evident when the scleral lens is discontinued at one visit and steepened at a later visit; the patient experienced almost complete resolution of the corneal staining. If the epithelial break had been caused by a lack of stromal integrity, the epithelium would not have healed by discontinuing contact lens wear or improving the fit. In order to give this patient adequate vision, a scleral lens was deemed necessary. Because an adequate fit could not be obtained with a scleral lens due to superficial neovascularization and fibrosis of the ICRS, the patient was referred for an explantation evaluation.

Corneal Neovascularization

Infectious Keratitis

This is one of the four leading causes of ICRS explantation.3 In order to make this a definitive diagnosis, cultures must be positive.3 In the case reported here, preoperative cultures and pathology of the corneal epithelium as well as post-operative cultures and pathology of the Intacs were both negative, rejecting microbial keratitis as a potential diagnosis.

Mild channel deposits around the ICRS

These channel deposits, made up of cells and protein, are usually found on the proximal end of the ring segment, near the incision.3Ruckofer et al. suggest that the deposits are caused by the physical separation of stromal lamellae when they are opened to create a channel for implantation of ICRS.4 They also reported that the incidence and density of deposits increase with segment thickness and duration of implantation. Although they report an incidence as high as 60%4, no deposits could be seen on clinical examination or using the VisanteTM Anterior Segment OCT in the patient described here.

Segment migration

This post-operative complication causes undesirable refractive outcomes.5The patient discussed in this case had no refractive complaints and stable vision with the help of scleral lenses. Segment migration has not been shown to cause discomfort similar to that experience by this patient.5 In addition, his topography was stable from the time we first saw him until his referral back to the surgeon, further confirming the stability of the segments’ position.

Corneal melting

This is one of the four leading causes of ICRS explantation.3Given the fact that the patient’s corneal staining was completely resolved following the discontinuation of scleral lens wear, corneal melting was not the causative factor here. The insult was the superficial cornea protruding forward and rubbing on the scleral lens. This is evident when the scleral lens is discontinued at one visit and steepened at a later visit; the patient experienced almost complete resolution of the corneal staining. If the epithelial break had been caused by a lack of corneal integrity, the epithelium would not have healed by discontinuing contact lens wear or improving the fit. In cases of corneal melting, the epithelium begins to breakdown, followed by stromal loss.3 The patient reported here had no stromal loss, as confirmed by the VisanteTM Anterior Segment OCT and slit lamp examination. In order to give this patient adequate vision, a scleral lens was deemed necessary. Because an adequate fit could not be obtained with a scleral lens due to superficial neovascularization and fibrosis of the ICRS, the patient was referred for an explantation evaluation.


The patient reported here had superficial corneal neovascularization after implantation with ICRS. ICRS is said to be promising, minimally invasive and reversible refractive treatment for the management of low to moderate myopia, keratoconus and post-LASIK ectasia.3,6,7 It was intended to achieve a clear central optical zone and preserve corneal tissue and defer corneal transplant surgery8. The rings are made of Polymethylmethacrylate (PMMA) in the shape of sections of a circumference and are inserted in a semicircular channel between the lamellae of the stroma. The 3 main ICRS on the market are Intacs (Addition Technology, Inc.), Ferrara (Ferrara Ophthalmics Ltd.), and Keraring (Mediphacos Ltd.).3 The changes induced in corneal curvature can be predicted using Barraquer’s Law; when a material is added to the periphery of the cornea, a flattening effect is achieved. 9 ICRS improve distance visual acuity, cylinder, and coma-like aberrations in post-LASIK ectasia10, but the indications for ICRS implantationfor this condition remain unclear.11 In a case series done by Brenner et al, the best candidates for ICRS in patients with post-LASIK ectasia were those who lost two or more lines of best corrected visual acuity because of ectasia and patients with grade 4 post-LASIK ectasia, defined as severe visual debilitation and a best corrected visual acuity less than 20/40.10 These patient showed a mean improvement of 2.89 lines of visual acuity 12 months after ICRS implantation. Furthermore, those who had grade 2 and 3 ectasia gained little acuity with implantation whereas those who had grade 1 ectasia experience loss of visual acuity after implantation.10

Intrastromal corneal ring segment implantation has been associated with intraoperative and postoperative complications.3 Intraoperative complications include segment decentration,12ICRS asymmetry,12inadequate channel depth,12superficial channel dissection with anterior Bowman layer perforation,3and anterior chamber perforation.3Although ICRS are usually well tolerated, some in vitro studies found activation of keratocytes, accumulation of lipids in cells and new collagen formation after implantation.13 Several postoperative complications have been described, including ring segment extrusion,3,12corneal neovascularization,3,6,12infectious keratitis,3,12mild channel deposits around the ICRS,3segment migration,3,12and corneal melting.3In the U.S. Food and Drug Administration phases II and III clinical trials, for Intacs, segment removal was necessary in 4.68% of eyes.8 The authors of this study concluded that intrastromal ring segments were safely, effectively, and easily removed, with a return to preoperative refractive status within 3 months.8

Corneal neovascularization after Intacs has not been frequently reported6,14; it is usually superficial and localized to the site of the surgical wound.6In a study of 33 eyes with keratoconus that underwent Intac surgery, Siganos and associatesfound superficial, mild vascularization at the wound site in 1 eye after 2 months.15Kymionis and associatesdescribed similar findings in 2 of 10 eyes treated with Intacs for post-LASIK ectasia.16 Both Al-Torbak et al and Cosar et al reported cases of deeper vascularization noticed 7 months and 3 years after surgery, respectively.6,14Cosar speculates that hypoxia of the cornea superficial to the Intacs may be the triggering factor for neovascularization as no inflammation was found on clinical examination14. Both Al-Torbaket al and Cosar et al report disappearance of the vessels after treatment with explantation of the Intacs and anti-inflammatory therapy, suggesting that the Intacs incited the neovascularization.6,14

If the causative factor is not removed, it is safe to assume that the neovascularization may continue to progress. Although a scleral lens is a good indication for the visual correction of a post-LASIK ectasia cornea with ICRS, if the neovascularization and firbovascular growth progresses, no scleral lens can be adequately fit. Therefore ICRS explantation would be necessary. In order to achieve adequate visual acuity, the patient would need to be refitted post-surgically.


In the patient reported here, a scleral lens fitting, necessary to achieve adequate visual acuity, could not be executed with success on the left eye until ICRS removal was completed. The patient’s inferior ICRS was causing hypoxia in the lower cornea, inducing superficial neovascularization and outward fibrovascular proliferation, causing corneal epithelial breakdown when a scleral lens was being worn and moderate to severe discomfort. Following inferior ICRS explantation, a scleral lens was successfully fit and the patient satisfied. In addition, the neovascularization is expected to regress because the insult is now removed. It was extremely rewarding to use these lenses and thereby provide clear vision to a patient who had been struggling with poor and unstable vision following his LASIK procedures. Although fitting a scleral lens on an eye with ICRS complications did not come without its challenges, following appropriate evaluation and treatment by an outside cornea specialist, adequate vision and comfort was achieved.

With the increasing recent interest of clinicians and manufacturers, scleral lenses are becoming far more “mainstream” in contact lens practice. As optometrists, we should strive to continuously update our expertise in the area of contact lens design, thereby providing our patients with the latest lens technology and best solution for their signs and symptoms.


Gardner D, Zimmerman A. Myopic shift secondary to hybrid lens wear. Contact Lens Spectrum. 2012 Jun;27: 44-48.


Van der Worp, EA Guide to Scleral Lens Fitting. [Forest Grove, Ore.]: [College of Optometry, Pacific University], 2010: 1-4.


Causes of intrastromal corneal ring segment explantation: Clinicopathologic correlation analysis


Ruckhofer J, Twa MD, Schanzlin DJ. Clinical characteristics of lamellar channel deposits after implantation of intacs. J Cataract Refract Surg 2000; 26:1473–1479


Intracorneal Ring Segment Explantation After Intracorneal Ring Segment Implantation Combined With Same-Day Corneal Collagen Crosslinking in Keratoconus


Al-Torbak A, Al-Amri A, Wagoner MD. Deep corneal neovascularization after implantation with intrastromal corneal ring segments. Am J Ophthalmol 2005; 140: 926-7.


Clinical outcomes after intrastromal corneal ring segments reoperation in keratoconus patients




Changes in Anterior and Posterior Corneal Parameters in Patients with Keratoconus After Intrastromal Corneal-ring Segment Implantation


Brenner LF, Alio JL, Vega-Estrada A, et al. Indications for intrastromal corneal &ring segments in ectasia after laser in situ keratomileusis. J Cataract Refract

Surg 2012; 38:2117 – 2124.


Evolution in the use of intrastromal corneal ring segments for corneal ectasia


Miranda D, Sartori M, Francesconi C, Allemann N, Ferrara P, Campos M. Ferrara intrastromal corneal ring segments for severe keratoconus. J Refract Surg 2003; 19:645–653


Twa MD, Ruckhofer J, Kash RL, et al. Histologic evaluation of corneal stroma in rabbits after intrastromal corneal ring implantation. Cornea 2003;22:146–152.


Late onset of deep corneal vascularization: a rare complication of intrastromal corneal ring segments for keratoconus


Siganos CS, Kymionis GD, Kartakis N, et al. Management of keratoconus with Intacs. Am J Ophthalmol 2003;135:64–70.


Kymionis GD, Siganos CS, Kounis G, et al. Management of post-LASIK corneal ectasia with Intacs inserts. Arch Oph- thalmol 2003;121:322–326.

by Eiman Atia, Senior Optometry Student at the New England College Of Optometry
Stephanie Sturgis, Senior Optometry Student at the Pennsylvania College Of Optometry

Scleral lens technology has been around since 1888 and was first developed in Germany. However, the concept was first put on paper in the 15th century by Leonardo Da Vinci. They were the first contact lens to be developed but today they remain a highly under-utilized medical device. There are many anterior segment conditions that warrant usage of a scleral lens such as keratoconus, pellucid marginal degeneration, other atypical cones, dry eyes and Steven Johnson Syndrome. People who develop these conditions may be led to believe that the only option to address these issues is through invasive surgery. Some of these surgeries include LASIK, RK, ALK, CK, PRK, Intacs, and other types of corneal transplants. Of course with every surgery there are risks and complications and sometimes these surgeries do not always have the desired outcome. This paper will explore these procedures and their post-surgical complications that may indicate usage of scleral lenses.

More recently, refractive surgery has been a popular option for those who wish to discontinue wearing glasses or contact lenses to achieve clear vision. The most common refractive procedure is laser assisted in-situ keratomileusis, otherwise known as LASIK. During this procedure, a topical anesthetic is used and an excimer laser is used to create a flap in the epithelial layer of the cornea. Once this flap is created, it is folded back and the laser removes some tissue underneath the flap to permanently re-shape the cornea and correct for the patient’s refractive error. Once the tissue is removed, the flap is then put back into place and the epithelial tissue is left to heal on its own. The amount of tissue removed is generally calculated based on the patient’s prescription and the thickness of their cornea. The eye is then usually patched overnight to prevent any rubbing or mechanical disturbance that would cause delayed healing. LASIK is an outpatient procedure that takes approximately 10-15 minutes per eye. Patients can expect to see their visual results in a few days after surgery, and sometimes can take months to see results. In order to be considered to have this surgery, it is generally recommended that the patient is at least 18 years of age and has a stable prescription. For some patients who have myopia (nearsightedness), their prescription may not stabilize until their mid to late 20s. Other contraindications for LASIK include diabetes, rheumatoid arthritis, lupus, glaucoma, herpes or cataracts, and pregnant or breastfeeding women. Patients should also take into account that once they hit presbyopic age, (around age 40), they will be dependent on reading glasses regardless of the LASIK procedure. Patients should also bear in mind that sometimes after the surgery, another LASIK procedure is needed to correct for residual refractive error. Some other symptoms that patients may experience after LASIK include glare, halos, dry eyes, decreased contrast sensitivity, light sensitivity, and poor night vision. In some other instances, complications may arise after surgery including permanent vision loss or decreased vision due to irregular astigmatism, flap complications such as epithelial ingrowth, diffuse lamellar keratitis( DLK), keratectasia, dry eyes, eye infections, haze, ocular pain and so on.

Scleral lenses not only correct for post-LASIK complications such as irregular astigmatism, corneal ectasia and other types of compromised corneas by the optics explained above, but they can also serve as protection and relief for those with dry eyes due to LASIK, by being in a constant moist environment throughout the day.

Radial Keratotomy is one of the earliest refractive eye surgeries which was introduced in 1978. During this procedure numerous incisions are made throughout the periphery of the cornea to correct for the refractive error. RK is intended for people with refractive errors ranging from one to four diopters of myopia. RK is not a very common procedure now as more modern techniques using excimer lasers are more accurate and have better predictability in their surgical results. In general, a good candidate for RK is quite similar to LASIK criteria. Contraindications are similar as well and include diabetes, autoimmune disease, and HIV/AIDS, herpes, glaucoma, pregnancy and dry eyes. In this type of eye surgery, it is strongly contraindicated in those with family or personal history of corneal disease. One of the biggest drawbacks of RK is that it may result in symptoms such as fluctuating vision throughout the day, halos, starbursts, and glare. Another drawback is that the prescription after surgery is not as stable as that of LASIK or PRK, and there tends to be a hyperopic shift in refractive error after a few years. The incisions from the surgery never heal. This leaves an open wound, which leads to more long term risk of infection. If the infection becomes untreatable, the only option left may be to receive a corneal transplant.

Due to the open wounds and possible fluctuating vision after surgery in some patients, soft contact lenses would potentially make these concerns an even larger issue. Since scleral lenses have a liquid interface between the lens and cornea, they help compensate for the fluctuation of vision throughout the day and also vault over the compromised cornea, therefore providing comfort and improved vision for these patients. Since the scleral lens vaults over the entire cornea and the cornea is cushioned in liquid it is protected from external insult.

Automated Lamellar Keratoplasty is an outdated refractive procedure similar to LASIK except that a microkeratome is used to remove tissue from the cornea instead of a laser. It is outdated because it is not as accurate as current methods of reshaping the cornea. A flap is created in this procedure and the underlying tissue is taken out to reshape the cornea, just as in LASIK. The recovery time is about 24 hours, however, the vision may not stabilize until weeks later. Candidacy and side effects are similar to LASIK as well. It can correct nearsightedness with refractions from -5.00 to -8.00. This procedure has been known to serve well for those in need of higher vision corrections but as said before, is less accurate.

Another procedure performed for those who are farsighted or hyperopic is known as Conductive Keratoplasty (CK). In this surgery, instead of a laser, a radio frequency energy wave gently remolds the cornea. The radio wave frequency used creates a thermal effect that shrinks the stromal layer in the cornea to re-shape the tissue. According to the FDA an ideal candidate is a patient who is over the age of 40 who has minimal difference between their manifest and cycloplegic refraction, about 0.50 D or less. The range of refractive error that can be treated ranges from +0.75 to +3.25 and astigmatism less than 0.75 D after a cycloplegic eye exam. A good candidate is also one who has had adequate distance vision since birth and can tolerate mild distance blur following the procedure. Contraindications for CK include those mentioned under LASIK and ALK as well as corneas with less than 560 microns in the periphery, or those on any systemic or ocular medications affecting the eyes.

Photorefractive keratectomy is a refractive procedure similar to LASIK in that an excimer laser is used to reshape the cornea. The difference lies in that there is no flap created in the PRK procedure. The laser is instead applied directly to the surface of the cornea. This accounts for a longer recovery period than LASIK would because the epithelial layer has to regenerate and replace the lost tissue. Usually it can take a few weeks to several months for patients to achieve their best corrected vision with this procedure. With LASIK, visual results are seen almost immediately whereas in PRK the improvement in vision will take much longer to occur because the epithelium has to regenerate. This procedure is used for all refractive errors including myopia, hyperopia, and astigmatism. The candidacy for this procedure, as well as the side effects are the same as LASIK. In preparation for the procedure the patient must refrain from wearing all types of contact lenses for a couple weeks before the procedure to ensure the cornea is in an unaltered state. After the surgery a bandage contact lens is placed on the cornea for 4-5 days to allow the epithelium to heal. Corneal ectasia is a common side effect in LASIK but it tends to be much less common after PRK procedures. If corneal ectasia were to occur a scleral lens would be the ideal management option for the patient.

Intacs were approved in 2004 by the FDA to help treat keratoconus and have also been used to help correct prescriptions in those who are nearsighted. These small semi-circular plastic rings are inserted in the stromal layer of the cornea to flatten its shape and essentially get rid of the keratoconus and myopia by altering the shape of the cornea or moving the cone, thus smoothing over the irregularities. This procedure involves making a small incision in the surface of the cornea while the eye is under anesthetic. The layers of the cornea are separated to ensure proper positioning of the Intacs. An instrument is used to assist in proper alignment of the Intacs. A suture is then used to close the incision and the healing process will begin. Glasses or contacts may still be required after this surgery takes place. Complications of Intacs include over or undercorrection, neovascularization near the incision site, migration of the Intacs toward the wound or extrusion of the Intacs. The best candidate known for this type of surgery are those who have keratoconus but cannot tolerate contact lenses and whose corneas are clear. The main purpose of Intacs is to help improve visual acuity because they will not cure keratoconus but can postpone the need for invasive surgeries such as corneal transplants. Despite improving visual function, Intacs will not prevent further stromal progression in keratoconus.

Scleral lenses can be used as an alternative to all of the above procedures as well as a post-surgical option to the above procedural complications. Scleral lens technology is a well-known, but underutilized medical device for patients who either have irregularly shaped corneas from disease or have who have experienced surgical trauma. These post-surgical patients with complications are sometimes left with fear and doubt that no option exists to improve their loss of vision. These distortions cannot always be corrected with the conventional methods of soft contact lenses, RGP contact lenses and glasses. Soft contact lenses are not a good option for irregular corneas because they mold to the same shape of the irregular cornea, causing light coming in to the eye to be scattered and form an unclear image. For those with dry eyes, they are also not well tolerated. RGPs are a better option than soft lenses because they are a harder material that can be custom made to essentially mask the irregularities of the damaged cornea. The tear film that sits underneath the lens negates the irregularity of the cornea as well, giving a smooth surface for light to focus on the back of the retina, forming a sharp image. These lenses have a smaller diameter and can sometimes be very uncomfortable and hard to adapt to. They do, however, provide good optics and crisper vision. Scleral lenses are another type of hard contact lens whose optics function similarly to that of RGPs. Scleral lenses differ in that they have a larger diameter, allowing them to vault over the cornea and sit on the sclera, the white of the eye, instead of the cornea. This provides better initial comfort and allows for an easier adaptation period than RGP lenses. The scleral lens is inserted in the eye with saline which acts as a liquid interface between the scleral lens and the cornea. Since the lens and liquid interface form a smooth surface, light will not be scattered and halos and glare can be eliminated. They can also be used to treat the over or undercorrection induced by surgery that eyeglasses and soft lenses cannot mask. As explained above, these lenses can be used to protect the eye from environmental irritants such as air conditioning, allergens and dust in those who have open wounds from surgeries such as RK, as well as those with dry eye. Keratectasia is a corneal condition that can result from non-surgical disease such as keratoconus, keratoglobus and pellucid marginal degeneration, as well as post-refractive surgeries including LASIK, PRK, RK, ALK, and CK and Intacs. During surgery, the corneal wall is made thinner and the pressure from internal forces from the eye can cause this malleable soft tissue to become distended and protruded. The only way to manage and achieve acceptable vision when this happens, is to have a scleral lens vault over this changing tissue. The concept of vaulting over changing tissue is also why these lenses work well for those who have had migration or extrusion from Intacs. If vision is improved with these lenses, there is absolutely no indication for a corneal transplant.

Patients who have had LASIK, RK, ALK, CK,PRK, and Intacs complications should consider scleral lenses as a first line treatment before considering more invasive procedures. A scleral lens can substitute for a corneal transplant by essentially replacing the irregular corneas with as a new optical surface. This new optical surface can serve to get rid of the symptomatic side effects of halos, glare, and dryness that may arise from these procedures. As mentioned earlier, conventional methods for correcting refractive error are not sufficient for these types of complications. Scleral lenses may be one of the only options readily available to treat these conditions without having to undergo surgery again and risk greater complications.

Scleral lenses have many other indications such as cosmetic, sports vision aid including those involved in activities such as swimming, and other settings with dust or dirt. They can be used as a protective device over corneal transplants and also have promising future implications of being used as a drug vehicle to the front surface of the eye. Scleral lenses are under-utilized and should be considered a first-line treatment/management for anterior segment conditions and complications.


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