Smooth Corneal Surface Research Articles

Hybrid technique of tuck-in Tenon's patch graft and tissue adhesives and bandage contact lens (TABCL) for large corneal perforation in microbial keratitis.

We describe the hybrid technique of tuck-in Tenon's patch graft (TPG) and tissue adhesive bandaged contact lens (TABCL) for large corneal perforations (>5 mm) with intact surrounding stroma. Management of large corneal perforation is often challenging, and urgent availability of donor cornea might be difficult; Tenon patch alone does not provide tectonic support; hence, this hybrid technique can be used safely in large perforations. This involves freshening the perforation edges, creating a 3600 stromal pocket, harvesting a Tenon's graft 1 mm oversized, tucking into the pocket, and suturing. Then areas of leakage were noted, and only those areas were supplemented with minimal cyanoacrylate glue (CG) at the graft edges. This technique was used in two eyes, one with a large corneal perforation and intact surrounding stroma and the other with 4 mm corneal fistula post healed keratitis with a failed primary TPG alone, and led to epithelialization and a smooth corneal surface at 6 weeks. The advantages include autologous tissue, cost-effective, easily available, minimal post-operative inflammation, vascularization, and surface irregularity.

Outcomes of Simple Limbal Epithelial Transplantation Without Amniotic Membrane Grafting in Unilateral Limbal Stem Cell Deficiency: A Case Series of 6 Patients.

This study describes the technique of simple limbal epithelial transplantation (SLET) without amniotic membrane grafting (AMG) in limbal stem cell deficiency (LSCD). Retrospective, interventional case series of 6 patients who underwent SLET without AMG were included. The procedure followed the standard technique, involving limbal biopsy from the healthy eye, resection of symblephera, and pannus dissection in the affected eye. Following host bed preparation, limbal explants were placed on the bare cornea and secured with fibrin glue. A large-diameter bandage contact lens was applied post surgery. No amniotic membrane was used. Preoperative data, including age, gender, cause of LSCD, best-corrected visual acuity, and previous ocular surgeries, were recorded. Postoperative clinical information, such as the duration of follow-up and recurrence of LSCD, best-corrected visual acuity, and other ocular examination findings, was recorded in an excel sheet. Preoperatively, 2 patients had total LSCD (secondary to a firecracker injury and excision biopsy for ocular surface squamous neoplasia). 4 patients had partial LSCD (3 chemical injuries, 1 firecracker injury). The mean age of participants was 30.67 ± 15.91 years, with a mean follow-up duration of 9.33 ± 8.04 months. Intraoperatively, all patients exhibited a smooth corneal surface after pannus removal. Postoperatively, all limbal explants remained securely attached, with complete corneal epithelialization achieved within 2 to 3 weeks. The ocular surface remained stable throughout, and no recurrence of LSCD was observed in any patient. No loss of explants was seen. The present series suggests that AMG may not be a necessary step for performing SLET.

Lamellar Keratoplasty Combined with Amniotic Membrane Transplantation for the Treatment of Corneal Perforations: A Clinical and In Vivo Confocal Microscopy Study.

Purpose To evaluate the clinical and in vivo confocal microscopy outcome of lamellar keratoplasty combined with amniotic membrane transplantation for the treatment of corneal perforations. Methods In this retrospective, noncomparative, and interventional case series, 13 eyes of 13 patients with corneal perforation were included. All eyes were treated with lamellar keratoplasty combined with amniotic membrane transplantation for corneal reconstruction. Age, underlying etiology, location, size of corneal ulcer, size of corneal perforation, hospitalization days and follow-up time, and corneal confocal microscopy were investigated. Aqueous leakage, anterior chamber formation, epithelial healing time, and visual acuity (VA) were monitored after operation. Results The cause of corneal perforation (n = 13) was classified as infectious (n = 13) was classified as infectious (n = 13) was classified as infectious (Conclusion Lamellar keratoplasty combined with amniotic membrane transplantation may be an alternative, safe, and effective surgical therapy in the treatment of corneal perforations in the absence of a fresh donor cornea. We recommend this surgery to treat with the size of corneal perforation of <4 mm in diameter no matter peripheral or central corneal perforation, especially who had immune-related diseases.

Recurrence of fungal keratitis in corneal transplant

В статье представлен клинический случай грибкового кератита в роговичном трансплантате. У пациента через 4 мес после сквозной кератопластики по поводу прогрессирующей язвы роговицы грибковой этиологии был диагностирован рецидив кератита. Была выполнена повторная сквозная кератопластика с последующим противовоспалительным лечением, но через 3 мес в центре трансплантата появился инфильтрат белого цвета с чёткими границами, который был иссечён. Лабораторное исследование иссечённого фрагмента выявило мицелий грибов рода Fusarium, проведена антимикотическая терапия амфотерицином В 0,2% местно и итраконазолом внутрь в течение 3 нед. Через 1 мес после проведённого лечения зрительные функции оставались на уровне правильной светопроекции, трансплантат был мутным на всей площади, отёк купирован, достигнута эпителизация роговицы. При осмотре в динамике через 2-3 мес болевой синдром отсутствовал, поверхность роговицы была гладкой без эпителиальных дефектов с помутнением трансплантата. Лабораторная диагностика является обязательной при подозрении на грибковую инфекцию. При проведении сквозной кератопластики при грибковом поражении роговицы необходимо иссечение инфильтрата в пределах здоровой ткани. Рецидивы грибковой инфекции в трансплантате роговицы происходят на границе «донор-реципиент».

Efficacy with Autologous Conjunctival Implant Associated with Phototherapeutic Keratectomy (PTK) in the Treatment of the Pterygium

Purpose: To evaluate the efficacy of new formula of the PTK calculated with the head-limbus-distance (=height) and limbal base length of the pterygium and ablation thickness on the anterior corneal curvature and visual acuity, associated with autologous conjuntival implant in patients with primary (Group A)and secondary(Group B) pterygium. Setting: This study was developed in the Department of Ophthalmology, Maggiore Hospital of Bologna. Design: Prospective non randomized study was conducted in 18 eyes of 18 subjects (9 eyes primary and 9 eyes with recurrent pterygium) operated with a dedicated PTK program. Methods: All patients signed informed consent before the start of the research. BCVA (Best Corrected Visual Acuity), mean refractive error (ME) and topographic astigmatism and recurrence of pterygium was followed. Mean follow up was 18.67 ± 6.13 months Min: 12 Max: 24 months. Results: Mean post-operative BCVA increased at 3-24 months compared with pre-op BCVA (p= 0.003). Mean post-op BCVA improved independent of the optical zone involvement in the pre-op (p= 0.845). Mean Pre-op astigmatism (Group A): was: 0,97 ± 2,7 (MIN: -2,8 Max: +5). Mean pre-op Astigmatism (Group B) :-0,33 ± 1,98 (MIN: -3 Max:+4). Astigmatism reduction in the group A: 0 D; Group B: -0,1D ± 0,74D MIN: -1 Max: +1. No statistically difference at 24 months from two groups in BCVA (p=0,59), Sf ( P=0,7), ME(p=0,7), astigmatism ( p=0,96) ANOVA. Recurrence of pterygium was: 0%. Conclusions: The dedicated programme of PTK was shown to be safe and effective for the treatment of the pterygium. BCVA can be improved by providing a smooth corneal surface in cases of optical zone involvement.

Umbilical Cord Patch Transplantation for Corneal Perforations and Descemetoceles.

Purpose To evaluate the clinical outcome of umbilical cord patch (UCP) transplantation for deep corneal ulcers with perforations and descemetoceles. Methods In this retrospective, noncomparative, interventional case series, 11 eyes of 11 patients with corneal perforation or descemetocele were included. The thickness and microstructure of UCP were measured. All eyes were treated with UCP and amniotic membrane transplantation for corneal reconstruction. Corneal ulcer healing, corneal thickness, anterior chamber formation, and best-corrected visual acuity (BCVA) were recorded and analyzed. Results The thickness of human UCP is 398.6 ± 102.8 μm (n = 5) with compact aligned fibers. The average age was 56.2 ± 15.8 (ranging from 22 to 75) years. The mean follow-up period was 7.1 ± 1.7 (ranging from 5 to 10) months. Four patients had descemetocele and 7 had perforation. The anterior chambers in all the 7 perforated corneas were formed at postoperative day 1. All patients regained a normal corneal thickness and smooth corneal surface within the first postoperative month. The vision improved in 10 eyes and remained unchanged in 1 eye. No recurrence nor side effects occurred during the follow-up. Conclusions UCP can serve as an alternative material in the treatment of corneal perforations and descemetoceles. This treatment option is also beneficial in those countries with limited cornea donors and eye bank services.

Bonds that belong in the Hall of fame.

Life could not exist without water and its unusual properties. These properties prevent lakes from freezing from the bottom and allow plants to defy gravity and raise it to their leaves. Water’s special properties are also critical to the function of the eye. They are conferred by the hydrogen bond. Water is a funny little molecule possessing twofold rotational symmetry in both its physical structure and electrical dipole. It comprises an oxygen atom that has two unpaired electrons covalently bonded to two hydrogen atoms that are located 105 degrees from each other. Electrons tend to be closer to the oxygen atom than the hydrogen atom, giving water its polarized charge. The attraction of the electropositive hydrogen ends of one water molecule to the electronegative oxygen ends of another water molecule produce hydrogen bonds. Hydrogen bonds are weak, 1/10 as strong as covalent bonds. Hydrogen bonds provide water with a structure and substance as the molecules form a loose crystal structure, or quasi-polymeric system. This creates high surface tension allowing water to bead up when placed on a glass slide or slither into a canaliculus by capillary action. This property allows the aqueous layer of the tear film to have a smooth uniform thickness, and for the compressibility of the tear film so the aqueous layer remains stable after a blink. It also allows for an adequate volume of tears to contain necessary vital gases (oxygen and carbon dioxide exchange), buffering salts, enzymes, and protective proteins. Its polarization allows for these substances to go into solution. To produce free water molecules that can evaporate, the hydrogen bonds of liquid water must first be broken. This takes a significant energy input (high specific heat). This requirement fortunately prevents the rapid evaporation of tears. The aqueous layer is sandwiched between the mucin and oily layers of the tear film. Membrane-bound mucins form the immediate protective coat of the cornea. The aqueous layer then creates a smooth corneal surface by filling in the gaps and adhering to the hydrophilic mucins with hydrogen bonds strong enough to allow for stability but weak enough to allow for fluid exchange. The outer oily layer of the tear film is non-polarized and therefore hydrophobic, allowing it to remain discrete and float on, rather than mix with, the aqueous layer. This enhances the refractive power of the eyes because oil has a higher index of refraction. The oil coating helps prevent aqueous evaporation. The Meibomian glands secrete the oil at the periphery of the tear film and it is these oily reservoirs that are picked up by the eyelid and spread over the tear film with a blink. The reservoirs themselves produce the hydrophobic barrier that limits the aqueous layer from running off. The hydrogen bond makes water a magical substance, allowing us to see and life to exist.

Clinical observation of two different surgical methods on treating pterygium

Objective To study the clinical efficacy of two different surgical methods on treating pterygium.Methods 108 cases ( 120 eyes) with primary pterygium,were divided into two groups:Group A was performed by the traditional pterygium excision combined with amniotic membrane transplantation.Group B was performed by the separation with alcohol combined with amniotic membrane transplantation as a contrast group.The period of following up was 12 months.Results In group A,the average time needed for the reconstruction of corneal surface was (5.10 ± 1.21 ) days,the recurrence rate was 12.90％.In group B,the average time needed for the reconstruction of corneal surface was (4.58 ± 1.26) days,the recurrence rate was 1.72％.The contrast between the results of two groups had significant difference.Conclusions The seperation with alcohol can remove the pterygium more thoroughly.It does not only provide a simple and safe method of formation of smooth corneal surface after the pterygium excision surgery,but also lower the recurrence rate after the surgery. Key words: Pterygium; Seperation, alcohol; Transplantation, amniotic membrane

Alcohol versus brush PRK: Visual outcomes and adverse effects

A smooth corneal surface prior to laser ablation is important in order to achieve a favorable refractive outcome. In this study, we compare PRK outcomes following two commonly used methods of epithelial debridement: Amoils epithelial scrubber (brush) versus 20% ethanol (alcohol). We reviewed records of patients who underwent wavefront-optimized PRK for myopia or myopic astigmatism between January 2008 and June 2010. Two treatment groups (brush vs. alcohol) were compared in terms of uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent (MRSE), corrected distance visual acuity (CDVA), and complications at postoperative months 1, 3, 6, and 12. One thousand five hundred ninety-three eyes of 804 patients underwent PRK during the study period: 828 brush-treated eyes and 765 alcohol-treated eyes. At 6 months postoperatively UDVA was ≥20/20 in 94.7% of brush-treated eyes versus 94.4% of alcohol-treated eyes (P = 0.907). At 1 month a higher percentage of brush-treated eyes maintained or gained one or more lines CDVA compared to alcohol-treated eyes (P = 0.007), but there were no other differences in UDVA, MRSE, or CDVA at any point postoperatively. At 1 month 75.4% of brush-treated eyes versus 70.4% of alcohol-treated eyes were free of complications (P = 0.032), and there were fewer brush-treated eyes with corneal haze (4.0% vs. 6.9%, P = 0.012) and dry eye (8.9% vs. 14.4%, P = 0.001). Although corneal haze was slightly more frequent in the alcohol group, most was trace and not significant. Although alcohol-assisted PRK had more minor complications in the early postoperative period, including corneal haze and dry eye, results for both groups beyond 1 month were comparable.

Corneal calcific band keratopathy

Calcific band keratopathy is a chronic degenerative condition characterized by the deposition of grayish to whitish opacities in the superficial layers of the cornea. It is usually associated with chronic ocular inflammatory conditions. Various treatment modalities have been used for the management of band keratopathy including mechanical debridement, chelation, and excimer laser phototherapeutic keratectomy (PTK). This review will discuss the cause and management of calcific band keratopathy. Recent use of combination treatments such as chelation, excimer laser, and amniotic membrane transplantation has renewed interest in the management of cases with band keratopathy in order to achieve faster epithelial healing and better postoperative outcomes. Careful case selection is required before deciding on the surgical management plan in cases with band keratopathy. Chelation is a cost-effective and straightforward procedure. An excimer laser PTK, although costly, can provide a smooth corneal surface. Combination treatment using amniotic membrane is reserved for selected cases to enhance epithelial healing.

Modified Phototherapeutic Keratectomy Technique for the Treatment of Elevated Corneal Opacities

A simple modification to the existing phototherapeutic keratectomy techniques to treat elevated corneal opacities is described for a case of severe bilateral macular dystrophy. After epithelial removal, a single drop of carboxymethylcellulose sodium 1.0% was applied centrally on the cornea. A spatula drawn smoothly stretched the drop in all directions without breaking its surface tension until the tip of the highest corneal elevation was seen. Large-diameter phototherapeutic keratectomy for 30-micron ablation was applied. This process was repeated several times, with decreasing amounts of tissue ablation as needed. Postoperative slit-lamp biomicroscopy revealed a smooth corneal surface with no elevated corneal opacities. The patient reported significant improvement with tearing and photophobia. This simple modification from painting to stretching the masking agent, thus transforming it to an ablatable mask, allowed for an effective and practical treatment of elevated corneal opacities. Carboxymethylcellulose sodium 1.0% is nontoxic, biocompatible, and requires no incubation or solidification time.

Amniotic Membrane Transplantation With Anterior Stromal Micropuncture for Treatment of Painful Bullous Keratopathy in Eyes With Poor Visual Potential

To report the use of anterior stromal micropuncture and amniotic membrane transplantation in the management of painful bullous keratopathy in patients with poor visual potential. Interventional case series. A retrospective review was performed to identify all patients who were treated by one of us (A.J.A.) between January 1, 2003, and June 30, 2005. Five eyes of 5 patients were identified. Conjunctival scarring secondary to glaucoma and retinal surgeries prevented mobilization of the conjunctiva in each of the patients identified. Each eye showed an intact, smooth corneal epithelial surface 1 month after the procedure, and no patients developed recurrent bullae formation during the follow-up period (average follow-up, 21 months; range, 11-34 months). Anterior stromal micropuncture and amniotic membrane transplantation is an effective technique for the management of bullous keratopathy in patients with poor visual potential. The success rate of this combined procedure may exceed that of either procedure performed alone.

A New Technique for Pterygium Excision: Air-Assisted Dissection

Purpose: To introduce a new technique which aids to remove the pterygium head and facilitates the establishment of a smooth and clear corneal surface without extra scraping or polishing. Material and Methods: We used 12 eyes of 12 patients undergoing pterygium excision. Air was injected into the side of the cap of the pterygium head with a 30-gauge needle, to create a dissection plane between the pterygium head and the cornea. After blunt dissection and excision of the pterygium, the conjunctival autograft technique was applied. Complications, postoperative smoothness and clarity of the cornea, and the recurrence rates were evaluated. Results: Dissection with air was successfully performed in 9 eyes (75%) in which blunt dissection was carried out easily. The corneas were clear and smooth postoperatively. In 3 eyes (25%) dissection with air was not completely successful, and scraping with a crescent blade had to be performed. One of the eyes with incomplete air dissection could not be clearly scraped. No major complications were observed. The recurrence rate was 8.3% (1 eye). Conclusion: This new technique is a safe, easy and cheap method for removing the pterygium head from the corneal surface, which also facilitates the establishment of a clear and smooth corneal surface.

Current Concepts and Challenges in Ocular Surface Reconstruction Using Cultivated Mucosal Epithelial Transplantation

Ocular surface disorders wherein corneal stem cells are deficient result in total conjunctivalization leading to severe visual dysfunction and blindness. Treatment of these diseases requires reconstruction of the ocular surface using epithelial transplantation to provide a smooth refractive corneal surface and biologic and physical barriers against a variety of destructive factors. Recently, regenerative medicine focusing on tissue-engineered techniques has been developed and established as a new clinical field. In particular, cultivated mucosal epithelial transplantation using well-differentiated, stratified epithelial sheets on amniotic membrane allows a rapid re-epithelial cover over the entire corneal surface, resulting in early reduction of inflammation and cicatrization. This surgical approach dramatically improves the prognosis of severe ocular surface diseases, especially severely inflamed corneal stem cell deficiency. This new approach not only provides early epithelialization but also allows reconstruction of the corneal surface using autologous cultivated epithelium including the cornea and oral mucosa from a small number of cell sources after amplification. Tissue-engineered strategies using autologous corneal or oral mucosal epithelial sheet transplantation avoid the risk of rejection and complications associated with immunosuppressive treatments. In addition to new cellular transplantation, combined automated lamellar therapeutic keratoplasty provides better refractive stromal interference and contributes to performance and safety of cataract surgery in severe corneal opacity cases. Although long-term prognosis and cell biologic behavior of tissue-engineered epithelium after transplantation should be carefully monitored, these recent surgical treatments have opened a new field for ocular surface reconstruction.

Long-term functional and topographic results seven years after epikeratophakia for keratoconus.

To analyze the long-term effect of epikeratophakia (EKP) on corneal topography and visual acuity of eyes with keratoconus. Retrospective study of 36 eyes 7.2 years after EKP. Four eyes underwent penetrating keratoplasty (PKP) and were excluded from further evaluation. Best-corrected visual acuity (BCVA) values were obtained from 32 eyes, corneal refraction and astigmatism from 23 eyes, surface asymmetry index (SAI) and surface regularity index (SRI) from 17 consecutive eyes that were operated upon after 1991, when the Tomey Topographic Modeling System became available. Only four eyes needed PKP. In addition to EKP six eyes had compression sutures and/or relaxing incisions, and one eye underwent photorefractive keratectomy. Mean refractive power of the cornea decreased from 51.8 to 45.8 and astigmatism from 7.2 to 3.8. SAI improved from 3.2 to 0.9 and SRI from 3.7 to 0.9. Mean BCVA was 0.3 preoperatively and 0.6 upon last follow-up. EKP was able to render PKP unnecessary in 32 of 36 eyes during the entire observation period. It was successful in permanently flattening the ectatic cornea and reducing astigmatism while restoring a symmetrical and smooth corneal surface. As a result, visual acuity improved considerably. In view of the young age of keratoconus patients needing surgery, and the fact that the lifetime of full-thickness corneal grafts is limited, EKP should be considered a valuable alternative to PKP in contact-lens-intolerant cases of keratoconus without central scarring.

Cyanoacrylate glue for corneal perforations: a description of a surgical technique and a review of the literature.

The effective early application of a cyanoacrylate glue corneal patch can aid in the management of small corneal perforations, corneal melts and wound leaks. Their use gives improved visual outcomes with reduced enucleation rates (6% vs 19%). It may also avoid the need for tectonic penetrating keratoplasty. Cyanoacrylate glue prevents re-epithelialization into the zone of damaged and naked stroma and prevents the development of the critical setting for collagenase production that leads to stromal melting. Cyanoacrylates also have significant bacteriostatic activity against gram-positive organisms. We describe a simple and easily reproducible method of cyanoacrylate corneal patch application, with neglible risk of inadvertent glue complications. It has the further advantage of a smooth corneal surface rather than an irregular surface as often occurs with direct application methods. With corneal application, the major concern is toxicity of cyanoacrylates through direct contact with the corneal endothelium and lens. Fibrin glues may be less toxic; however, they are not as readily available. The longer alkyl chains of currently available cyanoacrylate glues (e.g. Histoacryl) slows degradation significantly, limiting accumulation of histotoxic by-products to amounts that can be effectively eliminated by tissues. Vigilance in monitoring for infection/corneal infiltrate is necessary at all times, especially when the glue has been present for more than 6 weeks. Corneal patching with cyanoacrylate glue is a temporizing procedure only, buying time to allow healing secondary to medical treatment of the underlying condition, or allowing surgery to be elective and under more optimal conditions once inflammation has been reduced and the integrity of the globe restored.

Mathematical Simulation of Retinal Image Contrast After Photorefractive Keratectomy With a Diaphragm Mask

Photorefractive keratectomy (PRK) using a dilating diaphragm mask engraves a delicate three-dimensional staircase pattern into a formerly smooth corneal surface. The created steps are later smoothed by tear film and wound healing processes. The present study investigates, in a mathematical simulation, the effects that such staircase patterns and their smoothing may have on retinal image contrast. All simulations are based on the Gullstrand eye model and calculate retinal image contrast from point spread function (PSF) analysis of Gullstrand eyes treated by simulated PRK under various conditions. The simulations indicate that PRK can reduce retinal contrast markedly. The most critical factor for such a reduction is the step height of the ablation pattern. With step heights below 0.4 microns, loss of contrast due to the created staircase pattern is always moderate and should be restored during early wound healing. Complete wound healing may smooth out larger step heights. Micromovements during PRK also can lead to partial loss of retinal image contrast. Simulation of retinal contrast after PRK shows that step heights below 0.4 microns seem to be acceptable. A minimization of the micromovements during PRK can offset some of the reduction of retinal contrast.

Controlled lens formation with unapertured excimer lasers: use with organic polymers and corneal tissues

A theoretical model is developed which allows for well-defined lenses to be formed with different dioptric properties using lasers that are known to ablate a variety of materials. With the theoretical development as a guide an experimental arrangement is defined for the ArF excimer laser and this arrangement is used to form lenses with highly smooth surfaces in three polymeric materials (polymethyl methacrylate, polycarbonate, and polyvinyl chloride) to test the validity of the theory. As part of the procedure to obtain these lenses, ablation curves (etch depth per pulse vs log of the laser fluence) were measured for each of these polymers and these curves are also reported. The experiments were extended to the rabbit cornea in which the corneal button was reshaped as part of keratomileusis surgery. This preliminary experiment resulted in a clear cornea with a smooth corneal surface and a measured change of 3 diopters in the treated eye.

Production of Corneal Lesions Using High-Intensity Focused Ultrasound

In order to study the potential use of ultrasound as a noninvasive system for altering corneal curvature, we used high-density focused ultrasound at a frequency of 4.8 MHz and 7.9 MHz to produce corneal lesions in the rabbit eye. Intensity and duration threshold exposure conditions were determined for the production of minimally visible lesions. Threshold lesions were initially apparent as discrete white opacities resulting from stromal edema and disruption. Light and scanning electron microscopy of higher-energy, suprathreshold lesions revealed more extensive disruption, including the formation of a superficial stromal depression and a larger zone of edema and disorganization surrounding each lesion. Posterior stromal lamellae, endothelium, and Descemet's membrane were intact. Healing and reepithelialization resulted in a smooth corneal surface with no residual opacification. Threshold determinations predict safe exposure levels to the cornea during insonification of other ocular structures. Selective heating of the peripheral cornea using focused ultrasound may be a useful technique for correcting astigmatism.

Visual Distortion After Myopic Keratomileusis: Computer Analysis of Keratoscope Photographs

A patient experienced marked visual distortion following myopic keratomileusis, despite the presence of a clear graft and an apparently smooth corneal surface. A color coded topographic map of corneal surface power generated by computer analysis of a keratoscope photograph of the operated eye identified a degree of irregular astigmatism and asphericity not readily apparent from simple visual inspection of the keratoscope photograph. Contour map graphics display of corneal surface power is a useful clinical tool in the evaluation of visual distortion complications following myopic keratomileusis.