Uneven Corneal Epithelial Redistribution After Femtosecond Laser-Assisted Lenticule Intrastromal Keratoplasty in Correcting Moderate-to-High Hyperopia.

PURPOSE: To evaluate the characteristic of corrective epithelial thickness after femtosecond laser-assisted lenticule intrastromal keratoplasty (LIKE) to correct moderate-to-high hyperopia. METHODS: The prospective case series study of the LIKE procedure was performed to correct moderate-to-high hyperopia. The epithelial thickness map was generated by anterior segment optical coherence tomography (AS-OCT) in the corneal central 9-mm zone. Keratometry and corneal higher order aberrations were analyzed by Pentacam (Oculus Optikgeräte GmbH) preoperatively and postoperatively. RESULTS: In the 26 eyes of 13 participants who underwent the LIKE procedure for moderate-to-high hyperopia, the attempted spherical equivalence (SEQ) was +6.50 ± 1.09 diopters (D). Compared to the preoperative epithelial thickness maps, the postoperative epithelial thickness had become significantly thinner in the central 5-mm zone; the difference was 6 to 7 µm. The paracentral epithelium performed nonuniform remodeling; the thinnest epithelial thickness was located in the inferotemporal section, which has the greatest difference from the superonasal; the difference between these two was approximately 3 µm. Through correlation analysis, it was found that the sections with thinner epithelium were significantly related to corneal curvature and corneal vertical coma. CONCLUSIONS: The LIKE procedure can be used to correct moderate-to-high hyperopia. This study further indicated the epithelial remodeling characteristic after the LIKE procedure: the central and paracentral corneal epithelial thickness becomes thinner, and the epithelial thickness distributes non-uniformly, which may be the important factor of the postoperative curvature asymmetric distribution and induction of corneal vertical coma. [J Refract Surg. 2024;40(5):e321-e327.].

Use of nonsteroidal anti-inflammatory drugs in corneal epithelial ingrowth due to traumatic flap dislocation after LASIK: Case report.

RATIONALE: Ophthalmologists mainly treat epithelial ingrowth by lifting the flap and scraping the ingrowth or using scraping combined with phototherapeutic keratectomy, mitomycin C, and so on. The potential usefulness of nonsteroidal anti-inflammatory drugs in such circumstances has not been reported before. PATIENT CONCERNS: A 32-year-old man and a 25-year-old man underwent lifting and scraping of the flap and phototherapeutic keratectomy to remove the epithelial ingrowths. Unfortunately, the ingrowths recurred and continued to develop. DIAGNOSIS: The patients were diagnosed with corneal epithelial ingrowth. INTERVENTIONS: The administration of bromfenac sodium and fluorometholone eye drops. OUTCOMES: Epithelial ingrowths in both patients disappeared after 6 and 1 month of treatment, respectively. There were no adverse reactions to the eye drops. LESSONS: Nonsteroidal anti-inflammatory drugs may be broadly applied in the treatment of epithelial ingrowth after laser in situ keratomileusis.

[Comparison of the Effect of Autologous Serum on Therapy Resistant Corneal Erosions and Ulcers on the Corneal Graft vs. the Patient's Own Cornea]. / Die Wirkung von autologen Serumaugentropfen bei therapieresistenten Erosiones und Ulcera der Kornea bei eigenem im Vergleich zu transplantiertem Gewebe.

PURPOSE: The aim of this study is to compare the healing of corneal epithelial defects or ulcers on the corneal graft in comparison with the patient's own cornea after treatment with 100%, undiluted autologous serum eye drops. METHODS: In a retrospective study over 7 years, we analysed 263 treatments with autologous serum eye drops of persistent corneal epithelial defects (erosions [88%] vs. ulcers [12%]). We compared the epithelial healing tendency of patients with defects on their own cornea (51.9%) vs. patients who had previously undergone penetrating keratoplasty (48.1%). Complete epithelial healing during the 28 days of treatment was considered as therapeutic success. In addition, the recurrence rate of the epithelial defects after finishing the therapy was analysed. RESULTS: 88.2% of the epithelial defects healed during 28 days of therapy. The recurrence rate during follow-up was 5.1%. There was no significant difference with respect to success rate between corneal defects on the patient's own cornea (87.8%) and on the graft (88.6%; p = 0.137). There was a significantly lower success rate for corneal ulcers (74.2%) than for erosions (90.3%; p < 0.001). The recurrence rate of erosions was 4.4%, vs. 4.3% in ulcers during follow-up. CONCLUSION: The results of our study suggest that autologous serum eye drops are a non-invasive and safe alternative treatment for persistent corneal epithelial defects - with no significant difference in patients with a defect on their own cornea vs. defects on the corneal graft. The success rate, but not the recurrence rate, is significantly worse in ulcers than in erosions.

Outcomes and success of amniotic membrane transplantation for the treatment of corneal diseases.

PURPOSE: The amniotic membrane (AM), the inner layer of the placenta, is a semitransparent, avascular, and thin tissue that is useful due to its structure. Amniotic membrane transplantation (AMT) avoids the need for keratoplasty to prevent corneal perforating. The purpose of the study was to evaluate the visual (gain of or no change in visual acuity) and corneal outcomes (closure of the ulcer or corneal healing) of AMT in patients with ocular surface diseases. MATERIALS AND METHODS: This was a retrospective case control study (success or failure of the surgery). It was undertaken at a single academic center. The study cohort consisted of subjects with ocular surface diseases. Patients were treated with AMT for refractory ocular surface diseases. They were divided into five subgroups according to the preoperative diagnosis. The technique of AMT used was the onlay method with two layers of AM. Primary outcome measures included best corrected visual acuity (BCVA), the number of AMTs, and reepithelization of the corneal epithelium at the end of the treatment. Two weeks to six months were given to consider epithelial closure. Treatment success was defined as corneal healing within 6 months. RESULTS: A total of the 66 eyes of 66 patients (39 male/27 female) with a mean age of 44 ± 23 years (range 1-88 years) were included in the study. A single AMT procedure achieved epithelial closure in 74.2% (n = 49) of the eyes (53% in <15 days, 19.6% in 15-30 days, and 1.5% in 1-6 months). The fastest reepithelization occurred in neurotrophic keratopathy, 76.9% of which cases occurred within 15 days after the AMT procedure. Treatment failure was observed in five patients (7.5%), four with keratitis and one with neurotrophic keratopathy. The highest closure rates were found in persistent epithelial defects, graft-versus-host disease (GvHD), and bullous keratopathy, although there was no statistically significant difference in BCVA. Pairwise comparisons were made of neurotropic keratoplasty versus bullous keratopathy (P = 0.025), neurotrophic keratopathy versus keratitis (P = 0.004), GVHD versus keratitis (P = 0.003), and lastly, GvHD versus bullous keratopathy (P = 0.023). CONCLUSIONS: AMT is a safe, valuable, and fast treatment technique to treat corneal epithelial defects stemming from different etiologies that are refractory to conventional treatment.

Mechanical Epithelial Debridement versus Transepithelial Phototherapeutic Keratectomy Followed by Accelerated Corneal Collagen Crosslinking for Progressive Keratoconus.

OBJECTIVE: To compare the visual and topographic outcomes between mechanical epithelial debridement followed by accelerated corneal collagen cross linking (CXL) vs. transepithelial phototherapeutic keratectomy followed by accelerated CXL for treatment of progressive keratoconus. STUDY DESIGN: Quasi experimental study. Place and Duration of the Study: Armed Forces Institute of Ophthalmology (AFIO), National University of Medical Sciences, Rawalpindi, Pakistan, from December 2020 to December 2021. METHODOLOGY: On the basis of surgical technique used, patients were divided into two groups, Group A comprising of twenty eyes that underwent mechanical epithelial removal followed by accelerated CXL, and Group B comprising of twenty-two eyes that underwent transepithelial phototherapeutic keratectomy (t-PTK) followed by accelerated CXL. All variables were recorded preoperatively and 6 and 12 months postoperatively and included uncorrected visual acuity (UCVA), corrected distance visual acuity (CDVA), MRSE (manifest refraction spherical equivalent), and keratometric indices (flat K, steep K, Kmax , mean K, thinnest pachymetry, KPI, K prob, CLMIaa, and I-S). RESULTS: Forty-two eyes of twenty-nine patients were included in the study and were divided into two groups; Group A (mechanical epithelial removal followed by accelerated CXL) and Group B (t-PTK followed by accelerated CXL). The visual acuity improved in both the groups at 6 and 12 months, with more significant improvement in Group B in both UCVA (p=0.005) and CDVA (p=0.004) parameters. Keratometric outcomes showed significant differences in median values for flat K (p=0.048) and thinnest pachymetry (p=<0.001) in Group A, while significant difference in Kmax (p=0.024) and thinnest pachymetry (p=<0.001) in Group B. At 6 and 12 months, the CLMIaa, PPK, and I-S values were significantly lower in Group B (p=0.002 for all three indices). CONCLUSION: Transepithelial PTK followed by accelerated CXL yielded better outcomes regarding visual acuity and keratomertic indices as compared to mechanical epithelial removal followed by accelerated CXL and did not show any significant decrease in corneal pachymetry. KEY WORDS: Mechanical, Corneal Collagen Crosslinking (CXL), Transepithelial, Phototherapeutic keratectomy, Keratoconus.

Intracanalicular dexamethasone insert for post-corneal crosslinking inflammation and pain: the LINK study.

PURPOSE: To compare the efficacy of an intracanalicular dexamethasone insert with tapered topical steroid over 28 days after corneal cross-linking (CXL). SETTING: Single private practice, outpatient setting. DESIGN: Prospective observational randomized study. METHODS: This prospective randomized study investigated the efficacy of a dexamethasone intracanalicular insert on post-CXL pain and inflammation in progressive keratoconus patients. 20 patients (40 eyes) were enrolled; half were randomized to the dexamethasone intracanalicular insert group; half were prescribed a 28-day topical tapering steroid regimen. All patients were evaluated for pain scores, rate of re-epithelialization, ease of the post-CXL regimen, and need for rescue pain medication after standard bilateral epithelium-off CXL on postoperative day (POD) 1, POD3, and POD4 to 7, as well as postoperative week (POW) 1, POW2, POW3, and POW4. RESULTS: 20 patients (40 eyes) underwent standard-of-care epithelium-off bilateral CXL for progressive keratoconus. 10 patients were randomized to receive prednisolone eyedrops on a tapering schedule after CXL; 10 patients received dexamethasone intracanalicular inserts at the time of CXL. Regardless of the postoperative steroid regimen, there was no significant difference in the rate of re-epithelialization or use of rescue pain medication between groups. There was a nominal, however, statistical difference in pain scores between groups, favoring prednisolone eyedrops. Both groups stated no difficulty in following postoperative regimens. There were no adverse events noted in relation to treatment or the CXL procedure. CONCLUSIONS: Using a dexamethasone insert to alleviate pain and inflammation can be considered as a safe and efficacious part of a post-CXL regimen.

Evaluation of the Effect of Dermatochalasis and Upper Eyelid Blepharoplasty Surgery on Corneal Epithelial Thickness Alterations.

BACKGROUND: The aim of this study was to assess the effect of different grades of dermatochalasis (DC) and upper eyelid blepharoplasty (UEB) surgery on corneal epithelial thickness (CET), objectively using anterior segment-optical coherence tomography (AS-OCT) measurements. METHODS: 90 eyes of patients with DC were divided into three groups according to the severity of the DC. Forty-one eyes of age and sex-matched patients without DC were randomly selected as the control group. The study did not include patients with more than 2 D of spherical refractive error and more than 1.5 D of astigmatism, a history of previous eyelid surgery, ocular surface disease, contact lens use, and ophthalmic eye drop use. CET measurements of all the patients were performed with an AS-OCT (RTVue-XR, Optovue Inc., USA). RESULTS: There were statistically significant differences in the CET of the superior, superonasal, superotemporal, inferotemporal, and temporal sectors between the DC and control groups (p = 0.001, p = 0.02, p = 0.03, p = 0.02, p = 0.04, respectively). While there were no differences in CET among the sectors of the control group, there was a difference in CET among some sectors of the DC group. When the DC group was subdivided by severity, there was no difference between subgroups for CET across all sectors both preoperatively and postoperatively. In the measurements made 6 months after UEB surgery, the CET in all sectors increased statistically significantly compared to those measured in the preoperative period. CONCLUSION: This study revealed that DC reshaped the corneal epithelium and UEB surgery restored this remodeling 6 months after surgery. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Phototherapeutic keratectomy versus epithelial debridement combined with anterior stromal puncture or diamond burr for 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.

Clinical outcomes of epithelial ingrowth following laser in situ keratomileusis with mechanical debridement and compressed heating air flow: a case series.

PURPOSE: To describe the clinical outcomes of manual scraping of epithelial ingrowth followed by compressed heating air flow after laser in situ keratomileusis (LASIK). METHODS: We underwent a retrospective, noncomparative, and interventional case series. Twenty eyes of 17 patients were included in this study. Each patient with a history of LASIK underwent epithelial removal with mechanical debridement followed by compressed heating air flow. Our primary outcome was the recurrence of epithelial ingrowth after 3 months of follow-up, while our secondary outcomes were uncorrected distance visual acuity, corrected distance visual acuity, and complications after surgery. RESULTS: Ten patients (58.8%) were male, and eight eyes of seven (41.2%) patients underwent primary LASIK surgery, while12 eyes of 10 patients had flap-lift retreatment LASIK; sixteen eyes (80.0%) underwent mechanical microkeratome LASIK and four (20.0%) underwent femtosecond laser-assisted LASIK. Mean age at surgical removal of epithelial ingrowth was 37.0 years ± 9.3 years (range 24 to 55 years). There was recurrence of ingrowth in two eyes (10%) after 3 months of follow-up. The mean corrected distance visual acuity of patients before surgery was 0.07 ± 0.09 logMAR, and after the last follow-up was 0.02 ± 0.04 logMAR (p=0.06). The odds ratio of presenting with epithelial ingrowth after LASIK enhancement compared to primary LASIK was 29.41. CONCLUSION: Manual scraping followed by compressed heating air flow is a safe and effective treatment of clinically significant epithelial ingrowth after LASIK. At the last follow-up, no eye lost any line in corrected distance visual acuity.

[TransPRK in general anesthesia-An alternative for anxious patients]. / TransPRK in Allgemeinanästhesie ­ eine Alternative für Angstpatienten.

OBJECTIVE: The aim was to analyze and compare the refractive results of anxious patients treated with transepithelial photorefractive keratectomy (TransPRK) while under general anesthesia (ITN) versus patients treated under local anesthesia (TRO). MATERIAL AND METHODS: The TransPRK treatment was performed with the AMARIS 1050 RS laser (SCHWIND eye-tech-solutions GmbH, Kleinostheim, Germany) in a group of patients with ITN and a group of patients, treated as usual with TRO. The method used an aspheric aberration neutral ablation profile, as well as SmartPulse technology and 7D eyetracking. In ITN propofol and rocuronium were injected intravenously. The artificial respiration was via a resuscitation bag after intubation with a laryngeal mask. To achieve pain insensitivity in the group of patients in TRO three drops of Conjucain Edo 0.4% were instilled at intervals of a few minutes. Follow-up examinations were performed after 1 and 4 days and after 1 and 3 months. RESULTS: A total of 35 consecutive TransPRK laser treatments under ITN were retrospectively compared with a group of 699 eyes treated with TransPRK under TRO in the period from February 2017 to December 2021. The preoperative sphere had a range of -5.50 to -1.0 dpt, the average cylinder was 1.19 dpt and cylinders were treated up to 4.75 dpt. The results after 3 months follow-up showed a predictability of 100% eyes within the target correction of less than 0.5 dpt in ITN and in TRO 97%. The astigmatic correction showed 91% of eyes in ITN with less than 0.5 dpt and an angle of error of 83% within ±5°. In TRO 96% of eyes showed astigmatic correction with less than 0.5 dpt and an angle of error of 77% within ±5°. After 3 months 83% of eyes treated in ITN reached a visual acuity of 1.0 or more and 84% of eyes treated in TRO. CONCLUSION: The TransPRK performed in ITN led to equal refractive results than when treated as usual in TRO. For anxious patients there is the possibility of laser vision correction in ITN. Because of shorter treatment time and accordingly shorter time under general anesthesia, TransPRK is an advantage for LASIK surgery.

The Impact of Epithelial Remodeling on Surgical Techniques Used in Topography-guided Surface Ablation in Irregular Corneas.

PURPOSE: To analyze the optical consequences of epithelial remodeling in irregular corneas and their impact on the choice of different surface ablation techniques. METHODS: Anterior corneal and stromal surface topographies and epithelial thickness maps were analyzed in 24 eyes with irregular corneal optics. On two of the eyes, four different surface ablation techniques were simulated: (1) conventional anterior topography-guided photorefractive keratectomy (PRK), (2) transepithelial phototherapeutic keratectomy (PTK), (3) transepithelial anterior topography-guided PRK, and (4) stromal topography-guided PRK. RESULTS: Stromal surface topographies showed higher keratometric values, astigmatism, asphericity, and corneal higher order aberrations compared to topographies of anterior corneas covered by epithelium. Transepithelial anterior topography-guided PRK and stromal topography-guided PRK both resulted in regularized stromal surface, transepithelial PTK achieved partial regularization corresponding to the smoothing effect of the epithelial remodeling, and conventional anterior topography-guided PRK delivered after epithelial removal resulted in residual stromal surface irregularities. CONCLUSIONS: The difference in optical landscapes between the stromal and anterior surfaces in irregular corneas will represent a source of error when anterior topography-guided treatments are delivered on the deepithelialized stroma, as in conventional PRK. In contrast, anterior topography-guided ablations performed as transepithelial PRK and stromal topography-guided PRK delivered after epithelial removal address the full stromal irregularity, whereas transepithelial PTK alone may be used when topography-guided treatments are not possible. The authors conclude topography-guided PRK of irregular corneas should lead to significantly improved regularization only if it includes the effect of epithelial remodeling. [J Refract Surg. 2022;38(8):529-537.].

Bowman Layer Onlay Graft for Recurrent Corneal Erosions in Map-Dot-Fingerprint Dystrophy.

PURPOSE: The purpose of this study was to describe a case with recurrent corneal erosions who was treated with a Bowman layer (BL) onlay graft. METHOD: BL onlay transplantation was performed. RESULTS: In a 79-year-old female patient who presented with bilateral map-dot-fingerprint dystrophy and a history of recurrent painful corneal erosions, BL onlay grafting was performed to restore the corneal surface. At 1 month postoperatively, the epithelium was smooth over the graft, and until 1.5 years postoperatively, the patients had no complaints and no recurrence of the epithelial corneal erosion. CONCLUSIONS: In the described case, the transplantation of an isolated BL graft as an onlay proved to be an effective treatment for painful chronic recurrent erosions in the context of map-dot-fingerprint dystrophy in a patient who had undergone numerous unsuccessful previous treatments.

36-Month Outcomes of Mechanical and Transepithelial PTK Epithelium Removal Techniques Prior to Accelerated CXL for Progressive Keratoconus.

PURPOSE: To compare the 36-month visual, refractive, and topographic results and the optical quality of the cornea between mechanical and transepithelial phototherapeutic keratectomy (PTK) epithelium removal techniques prior to the accelerated corneal cross-linking (CXL) procedure in patients with progressive keratoconus. METHODS: Keratoconic eyes that received either mechanical epithelium removal or transepithelial PTK epithelium removal prior to accelerated CXL with 36 months of follow-up were included. The uncorrected (UDVA) and corrected (CDVA) distance visual acuity, spherical equivalent (SE), manifest astigmatism, flat keratometry (K1), steep keratometry (K2), maximum keratometry (Kmax) readings, thinnest corneal thickness (TCT), topographic astigmatism, point spread function (PSF), and aberrometric parameters including root mean square higher order aberrations (RMS HOAs), vertical coma, and spherical aberration (SA) were assessed preoperatively and 12, 24, and 36 months postoperatively. RESULTS: One hundred ten eyes of 110 patients with keratoconus were included (mechanical epithelium removal group: 69 eyes, transepithelial PTK epithelium removal group: 41 eyes). After the CXL procedure, the mean UDVA, CDVA, manifest astigmatism, RMS HOAs, SA, vertical coma, and PSF improved significantly throughout the follow-up visits in both groups (P < .05 for all variables). The improvement in the mean UDVA, CDVA, manifest astigmatism, K1, K2, Kmax, RMS HOAs, SA, vertical coma, and PSF were significantly better in eyes that underwent transepithelial PTK epithelium removal when compared to eyes that underwent mechanical epithelium removal during the follow-up period (P < .05 for all variables). CONCLUSIONS: Transepithelial PTK-assisted accelerated CXL seems to be more efficient in improving the visual acuity and the optical quality while stabilizing the cornea compared to the accelerated CXL with mechanical epithelium removal in patients with progressive keratoconus. [J Refract Surg. 2022;38(3):191-200.].

Flap amputation for long-standing post-LASIK flap dislocation with epithelial ingrowth.

A man aged 26 years presented with complaints of diminution of vision in his right eye for 1 year following a fist injury. He had a history of laser-assisted in situ keratomileusis in both eyes 5 years earlier. On examination, his uncorrected distance visual acuity (UDVA) in the right eye was 1.0 logMAR. Slit-lamp examination of the right eye revealed a superotemporal dislocation of the flap with coexisting epithelial ingrowth encroaching the pupillary area. Due to the presence of long-standing fixed flap folds, a flap amputation was performed along with removal of the epithelial ingrowth using 0.02% mitomycin C as adjunct. Postoperatively, the UDVA was 0.3 logMAR on day 1, which improved to 0.2 logMAR at 1 week. At 1 year, the UDVA was 0.2 logMAR improving to 0.1 logMAR with refraction, with minimal paracentral corneal haze and no signs of corneal ectasia.

Comparison of transepithelial and conventional photorefractive keratectomy in myopic and myopic astigmatism patients: a randomized contralateral trial.

BACKGROUND: To assess transepithelial photorefractive keratectomy (tPRK) in terms of corneal epithelial healing rate, postoperative pain, postoperative discomfort, and visual and refraction outcomes compared to mechanical epithelial debridement PRK (mPRK) and alcohol-assisted PRK (aaPRK). METHODS: In this double-masked, randomized clinical trial, thirty-nine patients underwent tPRK in one eye and mPRK in the fellow eye (arm A), and 33 patients underwent tPRK in one eye and aaPRK in the contralateral eye (arm B). All surgical procedures were done using the Schwind Amaris excimer laser. The area of corneal epithelial defect in all eyes was captured and analyzed using ImageJ software. RESULTS: Mean epithelial healing time was respectively 3.74 ± 0.82 and 3.59 ± 0.79 days in tPRK versus mPRK (P = 0.21) in arm A, and 3.67 ± 0.92 and 3.67 ± 0.74 days in tPRK versus aaPRK (P = 1.00) in arm B. Accounting for the initial corneal epithelial defect area, the epithelial healing rate was faster in conventional PRK groups compared to tPRK (both P<0.001) in both arms. However, there was no significant difference in safety, efficacy, spherical equivalent refractive accuracy, or corneal haze development between tPRK and conventional PRK groups (all P > 0.05). CONCLUSIONS: All three methods are effective in terms of visual and refractive outcomes. However, although time to complete re-epithelialization was similar with the three methods, the epithelial healing rate was faster in conventional PRK considering the initial corneal epithelial defect area, and the patients experienced less pain and discomfort in the first postoperative day. TRIAL REGISTRATION: IRCT, IRCT20200317046804N1 . Retrospectively registered 5 May 2020.

Surgical approaches to autologous limbal stem cell transplantation (LSCT) following severe corneal chemical burns.

Chemical injury of the conjunctiva and cornea are true ocular emergencies and require immediate intervention. They can produce severe, extensive ocular damage, including limbal stem cell deficiency (LSCD), and lead to irreversible visual loss. LSCD can be treated surgically through autologous limbal stem cell transplantation (LSCT). Autologous LSCT can be performed through cultivated limbal epithelial transplantation (CLET) or by direct grafting of limbal epithelial cells through conjunctival-limbal autografting (CLAU) or simple limbal epithelial transplantation (SLET). In this review we provide an overview of each surgical approach. CLET allows for a implantation of a large graft in the recipient eye while preserving donor cells. Its success rate is higher with an increased number of transplanted stem cells; failures tend to occur within the first year. CLAU is performed by directly transplanting autologous limbal stem cells from the patient's healthy eye, reducing the risk of immune rejection. This constitutes a risk for the donor eye, as the removal of stem cells from the fellow eye may lead to LSCD in the donor eye. SLET consists of direct implantation of donor stem cells on an amniotic membrane, thus avoiding the need for ex-vivo expansion. Combinations of CLAU and SLET within a single procedure have also been successfully utilized. Autologous LCST is an effective technique for surgical management of unilateral LCSD. Depending on the patient history and status of the fellow eye, either CLET, CLAU or SLET (including the combination of mini-CLAU and SLET) can be used to restore long-term function and prevent visual impairment.

Comparison of the efficacy of topical insulin with autologous serum eye drops in persistent epithelial defects of the cornea.

PURPOSE: To investigate the effect of topical insulin on epithelization in persistent epithelial defects (PED) refractory to usual treatment compared to autologous serum. DESIGN: Retrospective, consecutive case-control series. METHODS: The charts of 61 consecutive patients with PED treated with topical insulin (case group) and 23 treated with autologous serum (control group) were reviewed. Primary efficacy end points were the percentage of patients in which epithelization was achieved, as well as the rate and time until epithelization. Secondary efficacy point was need for amniotic membrane transplantation (AMT) or other surgeries. RESULTS: Mean time between PED diagnosis and start of topical insulin was 22.7 ± 18.5 days (range 13-115) and the mean area was 14.8 ± 16.2 mm2 (range 1.1-70.6). In the control group, mean time was 27.9 ± 16.8 days, mean epithelial defect area being 18.6 ± 15.0 mm2 (range 1.7-52.9). No differences in baseline characteristics were found between groups (p > 0.05). Epithelization was achieved in 51 patients (84%) on insulin and 11 patients (48%) on autologous serum (p = 0.002). In those patients, mean time until reepithelization was 32.6 ± 28.3 days (range 4-124) in the insulin group and 82.6 ± 82.4 days (range 13-231) in the autologous serum group (p = 0.011). The need for AMT was significantly lower in the insulin group (p = 0.005). PED recurrence was higher in patients treated on autologous serum (43%) compared with insulin (11%) (p = 0.002). CONCLUSIONS: Topical insulin is an effective treatment and safely promotes healing of PED. In our series, topical insulin presented better epithelization outcomes than autologous serum and could thus be considered as a first-line treatment.

The Effectiveness of Corneal Epithelial Debridement Performed with an Alcohol-Impregnated Sponge.

OBJECTIVE: To evaluate the clinical outcomes of patients who underwent corneal surgery with debridement of epithelium by localised application of an alcohol-impregnated sponge instead of the usual alcohol reservoir method. DESIGN: This study retrospectively included 52 eyes of 27 patients who underwent LASEK (laser-assisted subepithelial keratectomy) and CXL (cross-linking) surgery after application of this alcohol-assisted debridement method between January 2019 and April 2019. PARTICIPANTS: Twenty-four patients who underwent LASEK and three patients who underwent CXL surgery were included in this study, which comprised a total of 52 eye operations. METHODS: Epithelial debridement was performed after placing a 20% ethanol-impregnated sponge on the cornea for 20 seconds. RESULTS: The mean pachymetry value was 509.40 ± 30.37 µm, the mean preoperative spherical equivalent was - 2.14 ± 1.02 dioptres, and the highest myopia and astigmatism values were - 4.25 dioptres and - 2.75 dioptres, respectively. It was seen that the corneal epithelium was completely and easily debrided in a size identical to that of the applied sponge. CONCLUSIONS: Complete debridement of the corneal epithelium can be performed quickly, safely, and easily with this specially prepared sponge.