Long-Term Outcomes of Epithelial Debridement and Diamond Burr Polishing for Corneal Epithelial Irregularity and Recurrent Corneal Erosion

Classic lattice corneal dystrophy: a brief review and summary of treatment modalities

PURPOSE

To provide a brief summary and comparison of the most recent literature on available and theorized treatment modalities for classic lattice corneal dystrophy (LCD). This paper aims to support practitioners in their management of this disease.

METHODS

A search was carried out on available literature through PubMed and Google Scholar of English language articles up to January 2023 that relate to the treatment of LCD. Due to scarcity of literature regarding specific novel therapies for LCD, results from other corneal pathologies (granular corneal dystrophy, corneal scarring) are sometimes included for contrast, which is clearly denoted.

RESULTS

LCD is a slowly progressive disease that leads to recurrent epithelial corneal erosions, stromal haze, corneal opacification, substantial discomfort, and visual impairment. Due to its autosomal-dominant inheritance pattern, this disease can persist throughout ancestral lines and requires consistent treatment and follow-up. An optimal management plan is necessary to (1) prolong years of life with best achievable visual acuity; (2) treat painful recurrent corneal erosions as they occur; (3) ensure proper follow-up throughout the life of a patient, as well as monitor at-risk offspring; and (4) monitor efficacy of treatment.

CONCLUSIONS

This paper addresses (1) treatment for early disease including corneal epithelial debridement, photo therapeutic keratectomy (PTK), femtosecond laser-assisted lamellar keratectomy (FLK), and others; (2) treatment for late disease including full thickness keratoplasties and anterior lamellar keratoplasties; and (3) potential future treatment considerations including a wide variety of topical/systemic, genetic, and regenerative approaches.

Transepithelial phototherapeutic keratectomy for treatment-resistant recurrent corneal erosion syndrome

BACKGROUND

To evaluate the efficacy and safety of trans-epithelial phototherapeutic keratectomy (TE-PTK) as a treatment for recurrent corneal erosion syndrome (RCES) in patients with symptoms refractory to conventional treatments.

METHODS

All patients who received TE-PTK treatment for RCES had failed 3 or more conventional treatments and were reviewed, and if met criteria, approved by healthcare workers of the British Columbia public health authority (Medical Services Plan (MSP). A retrospective chart review and telephone survey were conducted at the Pacific Laser Eye Centre (PLEC). Exclusion criteria were ocular co-morbidities potentially affecting treatment efficacy.

RESULTS

This study included 593 eyes of 555 patients (46.2% male; 50.9 ± 14.2 years old) who underwent TE-PTK. The leading identified causes of RCES were trauma (45.7%) and anterior basement membrane dystrophy (44.2%). The most common pre-PTK interventions were ocular lubricants (90.9%), hypertonic solutions (77.9%), and bandage contact lenses (50.9%). Thirty-six eyes had undergone surgical interventions such as stromal puncture, epithelial debridement, or diamond burr polishing. Post-PTK, 78% of patients did not require any subsequent therapies and 20% required ongoing drops. Six patients (1.1%) reported no symptom improvement and required repeat TE-PTK for ongoing RCES symptoms after initial TE-PTK. All 6 eyes were successfully retreated with TE-PTK (average time to retreatment was 11.3 ± 14.9 months). There was no significant difference in best corrected visual acuity pre- vs. post-operatively. The mean post-operative follow-up was 60.5 months (range: 5-127 months).

CONCLUSION

TE-PTK has a good efficacy and safety profile for treatment-resistant RCES. The third-party public health-reviewed nature of this study, the low recurrence rate of RCES, and the low PTK retreatment rate suggest that TE-PTK might be considered for wider use in the management of RCES.

Superficial Keratectomy: A Review of Literature

Superficial keratectomy (SK) is the manual dissection of the superficial corneal layers (epithelium, Bowman's layer, and sometimes superficial stroma). SK is done using a surgical blade or diamond burr. Some surgeons use intraoperative mitomycin C 0.02% or amniotic membrane transplantation to improve surgical outcomes. This literature review shows that SK remains an effective method for different indications, including tissue diagnosis, excision of corneal degenerations, dystrophies, scarring, recurrent corneal erosions, and retained corneal foreign body.

Treatment of Epithelial Basement Membrane Dystrophy to Optimize the Ocular Surface Prior to Cataract Surgery

Purpose

To assess the effectiveness of cryopreserved amniotic membrane (CAM) after debridement in treating epithelial basement membrane dystrophy (EBMD) prior to cataract surgery.

Methods

This pilot study included 2 treatment groups: a prospective study group of 9 subjects with significant EBMD who received debridement followed by self-retained CAM, and a retrospective, control group of 10 consecutive subjects who received debridement followed by a bandage contact lens (BCL). Slit-lamp photography after fluorescein staining were used to monitor healing. Corneal topography and IOL calculation were compared at baseline and 1 month after the procedure. Refraction and ocular surface stability were also compared after cataract surgery.

Results

Corneal reepithelialization after debridement occurred in 4.6 ± 0.8 days in the study group and 6.8 ± 0.6 days in the control (p < 0.05). Corneal topography showed changes in curvature from 43.5 ± 1.2D at baseline to 44.6 ± 1.2D at 1 month in the study group and from 45.0 ± 0.6D to 45.7 ± 0.8D in the control (p = 0.38). Average change in IOL calculation was 1.56 D in the study group, compared to 0.95 D in control (p = 0.29). Post-cataract refraction in both groups was within ±0.5 Diopter of the anticipated, and corneal surface remained stable without EBMD recurrence.

Conclusion

Management of ocular surface disorders prior to cataract surgery stabilizes IOL calculation and reduces postoperative refractive surprises. CAM relatively accelerated healing after debridement; however, it was not better than BCL in stabilizing the ocular surface and improving visual outcome. The use of CAM in cases of EBMD remains speculative.

Phototherapeutic keratectomy versus epithelial debridement combined with anterior stromal puncture or diamond-dusted burr for treatment of recurrent corneal erosions

OBJECTIVE

To compare outcomes of phototherapeutic keratectomy (PTK) versus epithelial debridement combined with anterior stromal puncture (ASP) or diamond burr for the treatment of recurrent corneal erosions (RCES) in a large tertiary centre.

METHODS

Patients with a diagnosis of RCES secondary to trauma or epithelial basement membrane dystrophy who underwent a surgical procedure between 2009 and 2019 were included in the study. The following data were collected: demographics, ocular history, prior medical treatment, ocular surgeries, intervention, complete epithelialization at postoperative week 1, recurrences, and complications. Recurrence was defined as either an objective finding of a corneal epithelial defect or symptoms suggestive of recurrent epithelial erosion on history. Recurrence rate and time to epithelialization were compared between groups.

RESULTS

A total of 97 eyes (73 patients) were included in the study. Mean patient age was 51 ± 16.1 years, and mean follow-up was 474 days. RCES was secondary to epithelial basement membrane dystrophy in 80% (n = 78 of 97), trauma (15%, n = 15 of 97), or idiopathic (4%, n = 4 of 97). Epithelial debridement with ASP was performed in 34 eyes (35%), diamond burr in 33 eyes (33%), and PTK in 30 eyes (31%). Compared with epithelial debridement with ASP (recurrence 29.4%), the recurrence rate was significantly lower for both the diamond burr (9.1%, p = 0.031) and PTK groups (10%, p = 0.048). The diamond burr and PTK groups also had a significantly higher rate of complete epithelialization at 1 week (p < 0.05).

CONCLUSION

Compared with epithelial debridement with ASP, diamond burr and PTK have significantly lower rates of recurrence and time to epithelialization and may be considered first for surgical management of RCES.

Optimizing the ocular surface prior to cataract surgery

PURPOSE OF REVIEW

Ocular surface disease can significantly impact the outcomes of cataract surgery. Recent studies have examined the efficacy of several new dry eye disease (DED) therapies, the extent to which epithelial debridement affects keratometric measurements in epithelial basement membrane dystrophy (EBMD) and Salzmann nodular degeneration (SND), and the predictability of refractive error following combined pterygium and cataract removal. This review aims to incorporate these newer studies in updating and further emphasizing the need for careful management and optimization of common ocular surface conditions prior to cataract surgery.

RECENT FINDINGS

Common ocular surface conditions such as DED, EBMD, SND, and pterygium can cause significant irregular astigmatism and higher-order aberrations. Their resolution can substantially alter biometry measurements in preparation for cataract surgery, affecting the final visual outcome. Newer therapies for DED, such as topical lifitegrast and thermal pulsation treatment, can aid in this optimization process. If superficial keratectomy or excisions of lesions on the ocular surface are performed, sufficient healing time is needed to allow the ocular surface to reach stability prior to biometry measurements.

SUMMARY

Ocular surface optimization is key to successful cataract surgery planning and reaching desired outcomes.

Three-year outcomes of alcohol delamination of corneal epithelium for recurrent corneal erosions of traumatic etiology

Purpose

Alcohol delamination of the corneal epithelium (ADCE) is a therapeutic option for patients with recurrent corneal erosion (RCE) who do not respond to nonsurgical management of lubricants and extended wear contact lens. The aim of the study is to report on three-year efficacy and safety of ADCE for RCE of traumatic etiology.

Methods

This is a retrospective review of consecutive patients who underwent ADCE for traumatic RCE in a local hospital between January 2010 and January 2020. The outcomes at a 3-year follow-up review are included. Nonsurgical therapy used; intra- and postoperative complications were recorded. ADCE was only offered to those who remained symptomatic despite maximum topical lubrications and/or extended wear contact lens. Success was defined as the absence of recurrence of corneal erosion.

Results

Twenty-six eyes of 26 patients with RCE caused by trauma underwent ADCE. The mean age of patients was 39 years. The follow-up period was a minimum of 36 months. Three eyes (11.5%) had recurrence of corneal erosion after ADCE at the 3-year follow-up. Recurrence was noted at months 2, 23, and 36 postoperatively in these patients. All patients reported significant improvement in symptoms associated with recurrent erosion. Ten eyes (38.5%) stopped all topical lubricants postoperatively. No intra- or postoperative complications were noted in our study.

Conclusion

This study documents the long-term safety and efficacy of alcohol delamination of corneal epithelium at 3 years for patients with RCE of traumatic origin.

Preclinical Studies of a Novel Microfabricated Device to Treat Corneal Epithelial Disease

PURPOSE

Anterior stromal puncture is an inexpensive technique for treating recurrent corneal erosions but is often ineffective and cannot be used in the optical axis because of scarring. These studies tested a novel microfabricated imprinting instrument to assess its potential efficacy for the treatment of corneal epithelial disease in the optical axis.

METHODS

The device is made using glass rods, bundled and drawn through multiple iterative cycles, and then fused under high heat to generate a solid rod comprised of many parallel, aligned, cladded fibers. The rods are sliced into discs and then etched to yield designable spikes based on the borosilicate composition of the glass.

RESULTS

Imprinting the cornea yields a regular pattern of imprints. Histologic studies showed both nonpenetrating stable deformations of Bowman layer, with formation of stable epithelial attachments, and full thickness penetration, with superficial ingrowth of the basal epithelium.

CONCLUSIONS

Microimprinted corneal tissue shows focal subepithelial scarring without evidence of optically evident anterior stromal scarring, and may be an effective way of treating recurrent corneal erosions in the optical axis, which is not currently possible using standard anterior stromal puncture methods.

Long-term results of corneal collagen crosslinking for recurrent corneal erosion

BACKGROUND: Recurrent corneal erosion (RCE) is characterized by excacerbation and remission episodes, reduced patients quality of life affecting their daily and professional activities. In case of conservative therapy inefficacy surgical procedures are used (Bowmans membrane polishing with diamond drill, excimer laser phototherapeutic keratectomy, anterior stromal puncture, and amniotic membrane transplantation). All methods have their advantages and weak points, as well as a certain percent of recurrence. In this regard the use of corneal collagen cross-linking is of the interest as an alternative method of the RCE surgical treatment. MATERIALS AND METHODS: 18 patients (20 eyes) with RCE without central corneal stroma scars, aged from 30 to 66 (average 49,5 10,6, all women), after conservative treatment failure (more than 6 months) underwent cross-linking according to the Dresden protocol with the UVX device, version 1000, by IROC INNOCROSS (Switzerland). RESULTS: All patients were asymptomatic and had no recurrence during the observation period (from 1 to 6 years, in average 2,6 1,6). There was a slight but statistically significant BCVA improvement (from 0,93 0,09 at baseline to 0,97 0,07 after intervention). CONCLUSIONS: Crosslinking may be an additional and effective treatment in a number of RCE cases when there is no central corneal stromal scars present. To reduce stromal keratocytes alteration during the procedure modified protocols may be used.

Bandage Contact Lenses versus Deproteinized Calf Blood Extract Eye Gel for Recurrent Corneal Erosion Syndrome: A Case-Control Study

Background

The clinical efficacy of eye drops in the treatment of recurrent corneal erosion syndrome (RCES) is not satisfactory. Many studies have confirmed the positive effect of the bandage contact lens (BCL) in corneal diseases, but not many in patients with RCES. The purpose of this study is to investigate the efficacy of the BCL compared with deproteinized calf blood extract eye gel in the initial treatment of RCES.

Methods

Forty-seven patients with RCES treated in our hospital from September 2010 to September 2018 were retrospectively analyzed, including 24 cases (26 eyes) in the bandage contact lenses (BCLs) group wearing bandage contact lens and 23 cases (24 eyes) in the drug group treated with deproteinized calf blood extract eye gel. The efficacy was evaluated after 3 months of treatment, with a mean follow-up time of 21.15 ± 1.71 months in the BCL group and 20.87 ± 1.89 months in the drug group. Corneal erosion resolution, pain relief, visual acuity recovery time, recurrence and complications were observed.

Results

After 3 months of treatment, 22 eyes (22/26, 84.6%) in the BCLs group achieved complete resolution, compared with 14 eyes (14/24, 58.3%) in the drug group (P <0.05). The corneal healing time in the BCLs group was 4.77 ± 4.51 weeks, which was significantly shorter than that in the drug group (9.83 ± 5.93 weeks (P <0.01)). At 1 and 2 months after treatment, the visual analogue score (VAS) in the BCLs group (3.28 ± 1.15 at 1 month and 1.90 ± 0.77 at 2 months) decreased more significantly than that in the drug group (4.54 ± 0.89 at 1 month and 2.43 ± 0.93 at 2months, P =0.000 at 1 month and P=0.034 at 2 months). At 3 months after treatment, the mean BCVA in the BCL group (logMAR 0.03±0.08) improved more significantly than that in the drug group (logMAR 0.14±0.12,P=0.001). The complete recovery time of visual acuity was 5.46 ± 4.43 weeks in the BCLs group, compared with 10.33 ± 6.12 weeks in the drug group (P =0.003). During further follow-up, recurrence was observed in 2 eyes (2/22, 9.1%) of the BCLs group and 6 eyes (6/14, 42.8%) of the drug group. No patient in both groups developed adverse side effects.

Conclusion

Bandage contact lenses are safe and effective in the initial treatment of RCES. Compared with topical deproteinized calf blood extract eye gel, the use of BCLs can provide a higher cure rate, better pain control, faster visual recovery and lower recurrence rate.

Trial Registration

Chinese Clinical Trial Registry, ChiCTR2000031241. Registered 25 March 2020- Retrospectively registered, http://www.chictr.org.cn/edit.aspx?pid=51309andhtm=4.

[Recurrent corneal erosion: modern view of the problem]

Recurrent corneal erosion syndrome (RCES) is a common chronic disease associated with repeated episodes of epithelial disruption and is characterized by sudden onset of sharp pain in the eye, usually at night or upon waking, as well as redness, photophobia and lacrimation. The cause of the disease is considered to be impaired adhesion of the epithelial layer to the stroma, which is a consequence of abnormal regeneration of the basement membrane of corneal epithelium. A number of biological factors, including inflammatory mediators and proteinases in high concentrations, contribute to the destruction of the formed adhesion complexes. The basis of RCES diagnosis is characteristic medical history and biomicroscopy. An area of epithelium absence can be detected under direct illumination - more often in paracentral view - mainly in the lower third of the cornea, where an area of loose and irregular epithelium with microcysts or grayish inclusions can be seen. There may also be a card-like or «fingerprint» pattern. First of all, it is necessary to differentiate RCES from infectious lesions, which require a fundamentally different treatment regimen. It is believed that the first stage of treatment should include lubricants, drugs that promote epithelialization, inhibitors of matrix metalloproteinases and lipases. The «second line» of conservative treatment can include blood derivatives. If conservative therapy is ineffective, it is advised to use phototherapeutic keratectomy (PTK) or perform diamond burr polishing of Bowman's layer. The choice of a method for treating recurrent erosion should be based on the effectiveness of drug therapy, frequency of recurrence, duration of the disease, severity of clinical symptoms, availability of specific ophthalmic equipment and experience with it.

Burr-Assisted Anterior Lamellar Keratoplasty (DALK) in Patients with Corneal Stromal Scarring: A Case Series

Purpose

To describe a modified technique of deep anterior lamellar keratoplasty (DALK) assisted by diamond ophthalmic burr (DOB) in two patients with corneal stromal scarring.

Methods

Two patients with corneal stromal scarring underwent a modified DALK technique with corneal stromal polishing assisted by a DOB until the level of the Descemet membrane.

Results

There were no intra- or postoperative complications. Six months postoperatively, the corneal graft was clear, while corrected distance visual acuity improved in both cases.

Conclusions

Burr-assisted DALK seems to represent an alternative surgical technique in patients with corneal stromal scarring.

Electronic supplementary material

The online version of this article (10.1007/s40123-020-00248-8) contains supplementary material, which is available to authorized users.

Corneal injury: Clinical and molecular aspects

Currently, over 10 million people worldwide are affected by corneal blindness. Corneal trauma and disease can cause irreversible distortions to the normal structure and physiology of the cornea often leading to corneal transplantation. However, donors are in short supply and risk of rejection is an ever-present concern. Although significant progress has been made in recent years, the wound healing cascade remains complex and not fully understood. Tissue engineering and regenerative medicine are currently at the apex of investigation in the pursuit of novel corneal therapeutics. This review uniquely integrates the clinical and cellular aspects of both corneal trauma and disease and provides a comprehensive view of the most recent findings and potential therapeutics aimed at restoring corneal homeostasis.

Efficacy of a Topical Heparan Sulfate Mimetic Polymer on Ocular Surface Discomfort in Patients with Cogan's Epithelial Basement Membrane Dystrophy

Purpose: Treatment of persistent ocular discomfort in patients with Cogan's epithelial basement membrane dystrophy (EBMD) is a challenge for ophthalmologists. This study aimed to determine the efficacy of a topical heparan sulfate mimetic polymer (HSMP) in reducing ocular discomfort in EBMD patients. Methods: This retrospective, noninterventional study included 22 consecutive patients in 3 tertiary ophthalmological units with spontaneous, recurrent, acute ocular pain, resistant to various topical lubricants. After EBMD diagnosis, HSMP treatment was initiated while lubricating eye drops were continued. The main study outcome was the change in ocular discomfort assessed using the ocular surface disease index (OSDI) from initiation of treatment to last follow-up visit. Results: The mean OSDI decreased from 46.7 ± 22.3 to 31.6 ± 17.4 (P < 0.001) at first visit and 32.5 ± 17.9 (P < 0.01) at last visit. The rate of patients with severe ocular surface disease (OSDI >33) decreased from 68.2% to 36.4% at first visit and 42.9% at last visit. After a median follow-up of 8.5 months, 7 (31.8%) patients discontinued the HSMP treatment due to a marked improvement in ocular surface comfort and no recurrence of ocular pain, 5 (22.7%) due to lack of efficacy, and 1 (4.5%) due to an ocular adverse event (not treatment related). Eight patients continued treatment after the last visit and 1 patient was lost to follow-up. Globally, HSMP prevented acute painful episodes in 11 (61.1%) of 18 patients followed for ∼4 months. Conclusions: Topical HSMP may be an option for alleviating ocular discomfort in patients with EBMD resistant to standard symptomatic treatments.

Recurrent corneal erosion syndrome

Recurrent corneal erosion syndrome (RCES) is a disorder characterised by a dysfunctional epithelial ecosystem. It often begins after trauma, or in the setting of epithelial basement membrane degeneration or dystrophy. Historically, RCES has been understood as a structural derangement of the anterior corneal architecture. More recently, studies have demonstrated the important role of neuropeptides in corneal homoeostasis. Thus, RCES may also be understood as a disorder of corneal epithelial cell biology. Management of RCES can be challenging, but newer therapies have demonstrated improved efficacy for this condition. This review examines the aetiology and pathogenesis of RCES, and provides an update on current and emerging treatment modalities for the management of this disorder.

Recurrent corneal erosion: a comprehensive review

Purpose

To comprehensively review the literature regarding recurrent corneal erosion (RCE) and to present treatment options and recommendations for management.

Overview

RCE usually presents with sharp, unilateral pain upon awakening, in an eye with an underlying basement membrane dystrophy, prior ocular trauma, stromal dystrophy or degeneration, or prior surgery for refractive errors, cataracts, or corneal transplantation. Making the correct diagnosis requires a careful slit-lamp examination of both eyes coupled with a high degree of suspicion. Several treatments are commonly used for RCE but new therapies have been introduced recently. Conservative treatment consists of antibiotic and preservative-free lubricating drops, with topical cycloplegics and oral analgesics to control pain. Patients who are unresponsive to these therapies may benefit from therapeutic bandage contact lenses (BCL). Newer therapies include oral matrix metalloproteinase (MMP) inhibitors, blood-derived eye drops, amniotic membrane graft application, and judicious application of topical corticosteroids. Once the epithelium is healed, a course of hypertonic saline solution and/or ointment can be used. Surgical procedures may be performed in patients who fail conservative therapy. Punctal occlusion with plugs increases the tear film volume. Epithelial debridement with diamond burr polishing (DBP), anterior stromal puncture (ASP), or alcohol delamination should be considered in selected patients. DBP can be used for patients with basement membrane dystrophies and is the preferred treatment overall due to a low recurrence rate. ASP can be used for erosions outside the central visual axis. Excimer laser phototherapeutic keratectomy is an attractive option in eyes with central RCE since it precisely removes tissue while preserving corneal transparency. In patients with RCE who are also candidates for refractive surgery, photorefractive keratectomy can be considered.

Summary

Newly introduced therapies for RCE enable therapy to be individualized and lower the recurrence rate.

Superficial keratectomy: indications and outcomes

INTRODUCTION

To evaluate the indications and outcomes of manual blade superficial keratectomy STUDY DESIGN: Retrospective, nonrandomized, consecutive case series METHODS: Database search of patients from 2012-2017 who underwent superficial keratectomy was conducted at a tertiary care hospital cornea clinic. Charts of 121 patients (156 eyes) were reviewed who had at least 4 weeks of follow-up and both preoperative and postoperative measurements of best-corrected visual acuity or corneal cylinder. Outcome measures included: patient demographics, surgical indication, prior ocular history, best-corrected visual acuity (BCVA) changes, corneal and refractive astigmatism changes, recurrence of pathology, additional treatments required, and intraoperative and postoperative complications.

RESULTS

Mean patient age at time of operation was 63.3 (±14.8), 39% were male. Indications included epithelial basement membrane dystrophy, recurrent corneal erosion syndrome, Salzmann nodular degeneration, band keratopathy, and suspected ocular surface neoplasia. In eyes with epithelial basement membrane dystrophy, mean BCVA (20/47 to 20/40, P = 0.033), refractive astigmatism (1.76 ± 1.83 D to 1.15 ± 1.08 D, P = 0.010), and corneal astigmatism (1.44 ± 0.88 D to 1.06 ± 0.88 D, P = 0.022) significantly improved. Twenty-four percent (5/21) of eyes with recurrent erosions had symptoms return at a mean 6.5 months follow-up. No intraoperative complications were noted. The epithelium healed completely in all 156 eyes at final follow-up.

CONCLUSION

Superficial keratectomy is a simple, safe procedure that can be performed for a variety of conditions to improve visual acuity, reduce corneal astigmatism, and alleviate symptoms secondary to ocular surface pathology.

Phototherapeutic keratectomy for epithelial basement membrane dystrophy

Purpose

The purpose of this study was to evaluate the long-term efficacy of phototherapeutic keratectomy (PTK) in treating epithelial basement membrane dystrophy (EBMD).

Methods

Preoperative and postoperative records were reviewed for 58 eyes of 51 patients with >3 months follow-up (range 3–170 months) treated for EBMD with PTK after failure of conservative medical treatment at Byers Eye Institute of Stanford University. Symptoms, clinical findings, and corrected distance visual acuity (CDVA) were assessed. The primary outcome measure was symptomatic recurrence as measured by erosions or visual complaints >3 months after successful PTK.

Results

For eyes with visual disturbances (n=30), preoperative CDVA waŝ20/32 (0.24 Log-MAR, SD 0.21) and postoperative CDVA was ~20/25 (0.07 LogMAR, SD 0.12; P<0.0001). Twenty-six eyes (86.7%) responded to treatment, with symptomatic recurrence in 6 eyes (23.1%) at an average of 37.7 months (SD 42.8). For eyes with painful erosions (n=29), preoperative CDVA was ~20/25 (0.12, SD 0.19) and postoperative CDVA was ~20/20 (0.05. SD 0.16; P=0.0785). Twenty-three eyes (79.3%) responded to treatment, with symptomatic recurrence in 3 eyes (13.0%) at an average of 9.7 months (SD 1.5). The probability of being recurrence free after a successful treatment for visual disturbances and erosions at 5 years postoperatively was estimated at 83.0% (95% confidence interval 68.7%–97.0%) and 88.0% (95% confidence interval 65.3%–96.6%), respectively.

Conclusion

The majority of visual disturbances and painful erosions associated with EBMD respond to PTK. For those with a treatment response, symptomatic relief is maintained over long-term follow-up.