Multilayered amniotic membrane transplantation for severe ulceration of the cornea and sclera

Operating microscope-assisted reconstructive strategy for peri-implantitis: A case series report

BACKGROUND

Treating peri-implantitis with reconstructive means has been largely unpredictable due to access limitations for surface decontamination, unfavorable bony topography, difficulty in achieving wound stability, and inferior soft tissue qualities. A microsurgical approach with the use of the operating microscope (OM) that provides adjustable higher magnification (∼5-30 times) and coaxial illumination, coupled with the use of microsurgical instruments, may overcome, or alleviate some of the abovementioned obstacles, resulting in more predictable outcomes.

METHODS

Three patients received reconstructive therapy for correcting peri-implant defects under OM in private practice settings. After precise incisions to preserve soft tissue volume, the flaps were dissected prudently from underlying granulomatous tissues, which were subsequently removed, followed by controlled flap releasing under ∼10-15x magnification. Surface decontamination was performed using a piezoelectric ultrasonic device, air polishing, and hand instruments at ∼30x magnification. The biomaterial selections were dehydrated human de-epithelialized amnion-chorion membrane with mineralized allograft particulates in two cases and xenografts in one case, based on the surgeons' preference. Wound closure followed the non-submerged approach.

RESULTS

These cases demonstrated uneventful soft tissue healing, favorable radiographic bone fill, and disease resolution with follow-ups ranging from 2 to 4 years.

CONCLUSIONS

Preliminary data suggest encouraging outcomes after the microsurgical approach following biological as well as biomechanical principles for peri-implant defect reconstruction.

The Preparation and Clinical Efficacy of Amnion-Derived Membranes: A Review

Biological tissues from various anatomical sources have been utilized for tissue transplantation and have developed into an important source of extracellular scaffolding material for regenerative medicine applications. Tissue scaffolds ideally integrate with host tissue and provide a homeostatic environment for cellular infiltration, growth, differentiation, and tissue resolution. The human amniotic membrane is considered an important source of scaffolding material due to its 3D structural architecture and function and as a source of growth factors and cytokines. This tissue source has been widely studied and used in various areas of tissue repair including intraoral reconstruction, corneal repair, tendon repair, microvascular reconstruction, nerve procedures, burns, and chronic wound treatment. The production of amniotic membrane allografts has not been standardized, resulting in a wide array of amniotic membrane products, including single, dual, and tri-layered products, such as amnion, chorion, amnion-chorion, amnion-amnion, and amnion-chorion-amnion allografts. Since these allografts are not processed using the same methods, they do not necessarily produce the same clinical responses. The aim of this review is to highlight the properties of different human allograft membranes, present the different processing and preservation methods, and discuss their use in tissue engineering and regenerative applications.

Corneal Descemetocele Management with Multi-Layer Amniotic Membrane Transplantation in an Ocular Graft-versus-Host Disease Case

Background: Chronic ocular graft-versus-host disease (oGVHD) is a common ocular complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT), characterized by progressive inflammation of the ocular surface and refractory dry eye. In severe cases, sterile corneal perforation can occur, which poses a significant challenge, due to the low survival rate of grafts after corneal transplantation. Case Presentation: A 47-year-old female presented to our hospital with persistent dryness, foreign body sensation, and blurred vision in her left eye. Diagnosis of graft-versus-host disease with corneal descemetocele in the left eye was made after detailed history review and thorough examination. Multi-layer amniotic membrane transplantation was performed in the affected eye, resulting in amelioration of the patient's symptoms. This amelioration of symptoms provided the patient with a level of comfort that permitted additional time while awaiting corneal transplantation. Conclusions: We report a successful case of multi-layer amniotic membrane transplantation for the management of corneal descemetocele following allo-HSCT.

An in vitro comparison of human corneal epithelial cell activity and inflammatory response on differently designed ocular amniotic membranes and a clinical case study

Amniotic membrane (AM) is a naturally derived biomaterial with biological and mechanical properties important to Ophthalmology. The epithelial side of the AM promotes epithelialization, while the stromal side regulates inflammation. However, not all AMs are equal. AMs undergo different processing with resultant changes in cellular content and structure. This study evaluates the effects of sidedness and processing on human corneal epithelial cell (HCEC) activity, the effect of processing on HCEC inflammatory response, and then a case study is presented. Three differently processed, commercially available ocular AMs were selected: (1) Biovance®3L Ocular, a decellularized, dehydrated human AM (DDHAM), (2) AMBIO2®, a dehydrated human AM (DHAM), and (3) AmnioGraft®, a cryopreserved human AM (CHAM). HCECs were seeded onto the AMs and incubated for 1, 4 and 7 days. Cell adhesion and viability were evaluated using alamarBlue assay. HCEC migration was evaluated using a scratch wound assay. An inflammatory response was induced by TNF-α treatment. The effect of AM on the expression of pro-inflammatory genes in HCECs was compared using quantitative polymerase chain reaction (qPCR). Staining confirmed complete decellularization and the absence of nuclei in DDHAM. HCEC activity was best supported on the stromal side of DDHAM. Under inflammatory stimulation, DDHAM promoted a higher initial inflammatory response with a declining trend across time. Clinically, DDHAM was used to successfully treat anterior basement membrane dystrophy. Compared with DHAM and CHAM, DDHAM had significant positive effects on the cellular activities of HCECs in vitro, which may suggest greater ocular cell compatibility in vivo.

Surgical Management of Peripheral Ulcerative Keratitis: Update on Surgical Techniques and Their Outcome

Peripheral ulcerative keratitis (PUK) is an inflammatory, necrotic condition in the peripheral cornea which may end in corneal perforation and visual morbidity if not treated adequately. PUK can occur due to infectious or non-infectious causes. Early cases need medical therapy, both locally and systemically (for some cases). However, advanced PUK may necessitate surgical removal of inciting cause of the pathology and maintaining tectonic stability. Such surgical treatment, including corneal transplantations, may be used in an emergency setting or for visual rehabilitation following preliminary stabilization of the affected cornea. The outcome of these surgeries need to be analyzed to understand the long-term visual prognosis of such eyes. This is an attempt to analyze surgical modalities in the management of PUK and their outcomes.

Sutureless Lyophilized Amniotic Membrane Grafting for Corneal Epithelial Defects

OBJECTIVES

To report the tolerability, safety, and efficacy of the lyophilized amniotic membrane (AM) Visio-AMTRIX placed under a bandage contact lens (BCL) in treating persistent epithelial defects (PEDs).

METHODS

This retrospective study included consecutive patients with PEDs treated with a lyophilized AM placed under the BCL. Patients with PEDs who did not respond to medical treatment were included. Patients with a follow-up time less than 3 months were excluded.

RESULTS

Eleven eyes of 11 patients (mean age, 61.6±15.9 years) were included. Time from PED presentation to AM transplantation (AMT) was 27.7±4.9 days, with the mean PED area of 13.2±11.3 mm2. Complete resolution was achieved in 8 of 11 eyes after a single AM graft. The epithelial defect persisted after the first AMT in three eyes (27.3%), and a second graft was necessary to achieve complete healing. The corneal epithelial defect healed in an average of 11.0±4.4 days after grafting. After PED resolution, the best-corrected visual acuity significantly improved from 0.66±0.30 logMAR (20/91 Snellen) to 0.58±0.24 logMAR (20/77 Snellen) (P=0.036) compared with baseline. The AM resorbed within 2 weeks in all cases. No complication or recurrence was observed.

CONCLUSIONS

A sutureless lyophilized AM under the BCL can resolve PEDs with a significant improvement in vision.

Ophthalmic Complications and Managements of Sulfur Mustard Exposure: A Narrative Review

Sulfur mustard (SM) is a lethal chemical agent that affects many organs, particularly the eyes, respiratory system and skin. Even asymptomatic patients with documented SM vapor exposure may develop organ disorder many years later. Patients with even minor signs in the acute stage may experience late complications that necessitate surgery. Early decontamination and conservative measures could help the patients and decrease the complications. Despite decades of research, there is still no effective treatment for either acute or long-term SM-induced ocular complications. Even after multiple medications and surgical procedures, the majority of patients continue to have symptoms. For dry eye, punctual occlusion, autologous eye drops, and aggressive lubrication are used; for persistent epithelial defects (PED), tarsorrhaphy, amniotic membrane transplant, and stem cell transplantation are used; for total limbal stem cell deficiency (LSCD), living-related conjunctivolimbal allograft and keratolimbal allograft are used; for corneal vascularization, steroids, non-steroidal anti-inflammatory drugs, and anti-vascular endothelial growth factor prescribed; and for corneal opacities, corneal transplantation is done. Platelet rich plasma and topical drops containing stem cell transplantation for LSCD, photodynamic therapy paired with subconjunctival or topical anti-vascular endothelial growth factors for corneal vascularization, topical curcumin and topical ciclosporin-A for dry eye, and orbital fat-derived stem cells for PED are all alternative treatments that can be suggested. Despite the experimental and clinical research on the complications of SM exposure over the past decades, there is still no effective treatment for eye complications. However, supportive medical and surgical management has been applied with relatively good outcome.

Case Report: Use of Amniotic Membrane for Tectonic Repair of Peripheral Ulcerative Keratitis With Corneal Perforation

Purpose

To provide a perspective and surgical video demonstration of peripheral corneal ulceration and perforation managed with multilayered amniotic membrane transplantation.

Case Reports

Case 1 describes a 48-year-old female with progressive redness and pain, and an inferonasal corneal thinning and perforation in the left eye from peripheral ulcerative keratitis. She underwent conjunctival recession with amniotic membrane inlay and onlay (Sandwich technique) transplantation. The amniotic membrane integrated well, and her Snellen visual acuity improved from 6/21 preoperatively to 6/9 at 3 months post op. Case 2 describes a 78-year-old male with redness and pain with temporal corneal thinning bilaterally and perforation in the right eye from peripheral ulcerative keratitis. Both eyes underwent similar surgical intervention with smooth integration of the amniotic membrane in the cornea and improvement in the visual acuity. Both patients were also started on systemic immunosuppression in collaboration with the rheumatology team.

Conclusion

We report successful use of multilayered amniotic membrane transplantation for the treatment of corneal ulceration and perforation. The authors believe the simplicity of the surgical technique, easier access to amniotic membrane tissue, and lower induced post-operative astigmatism all provide advantages over alternative treatment modalities.

Amniotic Membrane Transplantation for Persistent Epithelial Defects and Ulceration due to Pseudomonas Keratitis in a Rabbit Model

Purpose

The use of amniotic membrane has been suggested in the treatment of infectious keratitis for its intrinsic anti-infective properties probably mediated by its anti-inflammatory effects. The aim of this study was to investigate the effect of amniotic membrane transplantation (AMT) along with ciprofloxacin to cure the primary stages of Pseudomonas keratitis.

Methods

In total, 28 rabbits were selected and divided in four groups as follows: group 1 as control, group 2 with amniotic membrane, group 3 with ciprofloxacin, and group 4 with amniotic membrane combined with ciprofloxacin. About 0.05 cc suspension of Pseudomonasaeruginosa, 27853 ATCC was injected into corneal stroma.

Results

The results showed groups of AMT, AMT + ciprofloxacin, and ciprofloxacin had 0% perforation while the control group had 85.6%. Average infiltration of 5.5 mm was observed in ciprofloxacin group, 5 mm in AMT + ciprofloxacin group, 24 mm in AMT group, and finally 23.75 mm for control. Amniotic membrane showed to be effective in prevention of cornea perforation as well as remission of Pseudomonas keratitis. There was no significant difference between ciprofloxacin groups in comparison with ciprofloxacin + AMT group. However, regarding the anti-inflammatory effect, the process of improvement of inflammation in ciprofloxacin + AMT group was faster.

Conclusion

Transplantation of amniotic membrane in the primary stages of Pseudomonas keratitis treatment remarkably prevents the disease and it can be used to control its process.

Long-Term Outcome After Superficial Keratectomy of the Abnormal Epithelium for Partial Limbal Stem Cell Deficiency

PURPOSE

To investigate the etiology and long-term surgical prognosis of the abnormal epithelium for partial limbal stem cell deficiency (LSCD), following superficial keratectomy DESIGN: Retrospective, interventional case series METHODS: This single-center, retrospective study was conducted to assess the prognosis of consecutive patients who underwent superficial keratectomy, with or without amniotic membrane transplantation (AMT), for the treatment of partial LSCD, from 2010 to 2019. We analyzed the etiologies of partial LSCD, surgical success rate, prognosis for recurrent cases, and the improvement in visual acuity.

RESULTS

We included 40 patients (51 eyes) with partial LSCD. All eyes were in clinical stage II without dense fibrovascular tissue. Idiopathy was the most common etiology (39%), followed by multiple surgeries involving the corneoscleral limbus (19%). All eyes attained corneal reepithelialization and transparency. Furthermore, the visual acuity improved or remained unchanged postoperatively. We observed recurrence in 19 eyes (37%) with a mean follow-up period of 26.3 months. Despite no significant difference in the recurrence rates among different etiologies, postoperative delayed epithelialization and extensive limbal involvement were identified as risk factors for recurrence (P < .001 and P = .013, respectively). Repeat surgeries were performed in 16 eyes. The final success rate was 84%.

CONCLUSIONS

Superficial keratectomy is useful for the treatment of partial LSCD of varied etiologies, with an expected improvement in visual acuity postoperatively. Although the procedure can be repeated and have a high success rate, there have been several cases of recurrence in the long-term postoperative course.

Prognosis and etiology of traumatic and non-traumatic corneal perforations in a tertiary referral hospital: a 30-year retrospective study

PURPOSE

To clarify the prognosis of corneal perforation, we compared the etiology and characteristics of patients with traumatic and non-traumatic corneal perforations.

METHODS

This retrospective observational study included patients treated for traumatic or non-traumatic corneal perforations at a single tertiary hospital from 1989 to 2019. The variables collected included the primary cause of corneal perforation, final best-corrected visual acuity (BCVA), and treatment administered. The initial treatment administered and treatment success rates were compared between the traumatic and non-traumatic groups. Multivariate linear regression analysis was performed to determine the predictors of final visual acuity.

RESULTS

Ninety eyes of 90 patients (mean age, 61.1 ± 19.7 years) were included. Traumatic and non-traumatic corneal perforations occurred in 40 (44.4%) and 50 eyes (55.6%), respectively. Among non-traumatic causes, infection and autoimmune disease were the causes for corneal perforation in 18 (20.0%) and 12 eyes (13.3%), respectively. The success rate for the closure of the perforated site with the initial procedure was significantly higher in traumatic corneal perforations than in non-traumatic corneal perforations (90.0% and 72.2%, respectively; p = 0.038). Patients with traumatic corneal perforation had significantly better final BCVA than those with non-traumatic corneal perforation (0.71 ± 1.18 and 1.52 ± 1.12, respectively; p = 0.0016). On multivariate analysis, older age and non-traumatic corneal perforation were significantly related to the final lower BCVA (p < 0.001 and p = 0.029, respectively).

CONCLUSION

Traumatic corneal perforation demonstrated a significantly better prognosis than non-traumatic corneal perforation. It is critical to consider the primary cause of corneal perforation to anticipate prognosis.

Surgical Application of Human Amniotic Membrane and Amnion-Chorion Membrane in the Oral Cavity and Efficacy Evaluation: Corollary With Ophthalmological and Wound Healing Experiences

Due to its intrinsic properties, there has been growing interest in human amniotic membrane (hAM) in recent years particularly for the treatment of ocular surface disorders and for wound healing. Herein, we investigate the potential use of hAM and amnion-chorion membrane (ACM) in oral surgery. Based on our analysis of the literature, it appears that their applications are very poorly defined. There are two options: implantation or use as a cover material graft. The oral cavity is submitted to various mechanical and biological stimulations that impair membrane stability and maintenance. Thus, some devices have been combined with the graft to secure its positioning and protect it in this location. This current opinion paper addresses in detail suitable procedures for hAM and ACM utilization in soft and hard tissue reconstruction in the oral cavity. We address their implantation and/or use as a covering, storage format, application side, size and number, multilayer use or folding, suture or use of additional protective covers, re-application and resorption/fate. We gathered evidence on pre- and post-surgical care and evaluation tools. Finally, we integrated ophthalmological and wound healing practices into the collected information. This review aims to help practitioners and researchers better understand the application of hAM and ACM in the oral cavity, a place less easily accessible than ocular or cutaneous surfaces. Additionally, it could be a useful reference in the generation of new ideas for the development of innovative protective covering, suturing or handling devices in this specific indication. Finally, this overview could be considered as a position paper to guide investigators to fulfill all the identified criteria in the future.

Results of Resorbable and Running Sutured Amniotic Multilayers in Sterile Deep Corneal Ulcers and Perforations

PURPOSE

To present the results of a modified surgical technique for secure tightening and fixation of multilayer amniotic membranes (AMs) in sterile deep or perforating corneal ulcers.

METHODS

We retrospectively analyzed the data of patients suffering from corneal ulcers who had been treated between February 2016 and June 2018 with running and resorbable sutures to fixate multilayer AMs. The parameters analyzed were gender, age, etiology of corneal ulcer, ulcer diameter, corneal thickness (CST) before and after the microsurgical procedure as measured with optical coherence tomography, number of inlays, repeat surgical procedures, follow-up duration in months, and rate of success (defined as a stable anterior chamber with improved CST, a negative Seidel test, and no need for any microsurgical keratoplasty during the first 6 months after treatment). The results were statistically evaluated using the Wilcoxon test. A P-value ≤0.05 was considered to show a statistically significant difference.

RESULTS

The CST increased significantly after AM transplantation (from 206.26 ± 114.93 μm at baseline to 454.70 ± 244.08 μm at 1-3 months; P < 0.001). Repeat multilayer transplantation was required in 7 of the 23 patients included (30.4%), in 6 of whom the treated eye was stable at month 6. In 2 of the 23 patients, perforating keratoplasty became necessary. One patient also demanded such a procedure to improve his visual acuity. The success rate was 91.3% (n = 21).

CONCLUSIONS

Running resorbable suture fixation of multilayer AMs proved to be an efficient means for the treatment of noninfectious deep or small perforating corneal ulcers.

Update on the application of amniotic membrane in immune-related ocular surface diseases

Immune-related ocular surface diseases, a group of diseases in which immune dysregulation damages the ocular surface, can induce uncontrolled inflammation and persistent epithelial defect, thus leading to the most severe forms of acute keratoconjunctivitis, dry eye disease, epithelial keratitis, stromal ulceration, and corneal perforation. As these diseases are often refractory to treatments, they have a threatening impact on the vision and life quality of patients. This review summarizes the current literature regarding the clinical application of sutured and self-retained cryopreserved amniotic membrane (AM) in treating Stevens-Johnson syndrome/toxic epidermal necrolysis, ocular graft-versus-host disease, Sjögren's syndrome, Mooren's ulcer, and peripheral ulcerative keratitis. Current evidence supports the safety and effectiveness of AM, especially self-retained cryopreserved AM, in decreasing ocular surface inflammation, promoting corneal epithelial and stromal healing, improving visual acuity, and preventing sight-threatening complications. Future studies are still required to validate the above findings and explore the varied application methods of AM to improve the clinical efficacy in maintaining ocular surface health.

Amnion-Chorion Membrane in Open-Wound Approach for Localized Horizontal Ridge Augmentation: A Case Series Report

INTRODUCTION

Guided bone augmentation often requires extensive releasing of the mucoperiosteal flap to achieve primary wound closure, an invasive procedure that can compromise the keratinized tissue volume and increase patient morbidity. Amnion-chorion membranes have been used to actively promote healing in chronic open-wound situations in the medical field, suggesting that they could be used in a similar manner in the oral cavity.The ability to use open-wound healing techniques for guided bone regeneration would allow clinicians to avoid invasive procedures that cause additional tissue trauma at the surgical site.

CASE SERIES

Amnion-chorion membranes were applied over the bone grafting material augmenting localized horizontal ridge defects, and a gap between the flaps was left intentionally during healing. Minor flap releasing procedures were performed in these cases, which demonstrated uneventful soft tissue healing, good volume of bone regeneration and preserved keratinized tissue.

CONCLUSIONS

Preliminary clinical outcomes suggested contained minor horizontal ridge defects may be treated satisfactorily in a controlled, open-wound healing manner that reduces surgical trauma, chair time, and patient morbidity.

Management of corneal perforations: An update

Corneal perforation is a potentially devastating complication that can result from numerous conditions that precipitate corneal melting. It is associated with significant morbidity and prompt intervention is necessary to prevent further complications. Causes include microbial keratitis, ocular surface disease, and autoimmune disorders and trauma. Various management options have been described in the literature to facilitate visual rehabilitation. This rview discusses the treatment options that range from temporising measures such as corneal gluing through to corneal transplantation, with decision making guided by the location, size, and underlying aetiology of the perforation.

Tectonic keratoplasty using small incision lenticule extraction-extracted intrastromal lenticule for corneal lesions

Objective

This study investigated an alternative approach for obtaining donor corneas for keratoplasty that can be used in nations with high corneal demand and high costs for treatment of non-healing ulcers or lesions.

Methods

Eighteen patients (18 eyes) who underwent tectonic keratoplasty using small incision refractive lenticule extraction (SMILE)-extracted lenticule were included. Data were recorded regarding age, corneal status, corneal lesion location and size, preoperative and postoperative visual acuity, lenticule layer, and additional medical history.

Results

Corneal thinning and corneal perforation in 13 and 5 patients, respectively, were treated with tectonic keratoplasty using SMILE-extracted lenticule. After tectonic keratoplasty, globe integrity was maintained in 16 of the 18 patients. The mean decimal visual acuity improved from 0.2555±0.3326 preoperatively to 0.3303±0.3487 at the final follow-up. Visual acuity improvement was greater in patients with corneal perforation than in patients with corneal thinning. In addition, visual acuity was most improved in patients with infratemporal lesions.

Conclusion

Tectonic keratoplasty using SMILE-extracted lenticule is a comparatively safe, effective, and reliable alternative approach for the treatment of corneal lesions.

Self-retained cryopreserved amniotic membrane for treating severe corneal ulcers: a comparative, retrospective control study

To compare the effectiveness of self- retained cryopreserved AM as an adjuvant therapy for infectious corneal ulcers. Retrospective, case–control study of 24 eyes of 24 consecutive patients with central and paracentral corneal infectious ulcers and initial visual acuity worse than 20/200. Among them, 11 eyes of 11 patients received additional placement of self-retained cryopreserved AM. Epithelialization and Best Corrected Snellen Visual Acuity (BCSVA) were compared between the two groups. At baseline, both groups had comparable age, gender, visual acuity (VA), size and location of corneal ulcer. Patients receiving additional placement of cryopreserved AM had significantly faster epithelialization within 3.56 ± 1.78 weeks vs 5.87 ± 2.20 weeks (p = 0.01) and achieved complete epithelialization in significantly more patients (72.7% vs 23.1% p = 0.04) despite overall larger baseline defect size (32.7 ± 19.5 mm² vs 21.5 ± 10.7 mm², p = 0.11). Consequently, the AM group had clinically significant BCSVA (> 3 lines) (81.8% vs 38.4%, p = 0.047) and total VA improvement (log MAR 0.7 ± 0.6 vs 1.6 ± 0.9, p = 0.016) compared to the control group at the time of complete epithelialization. In-office sutureless AM may be an effective adjuvant therapy in treating sight-threatening infectious corneal ulcers by promoting faster corneal epithelialization and overall better recovery of the VA.

Outcomes of Penetrating and Lamellar Corneal Patch Grafts

PURPOSE

To report the indications, long-term structural and functional outcomes, and prognostic factors for the success of penetrating and lamellar corneal patch grafts.

METHODS

This is a retrospective analysis of 49 patients who underwent the corneal patch graft procedure over 8 years. The baseline, preoperative, and postoperative characteristics along with their outcomes were evaluated.

RESULTS

Forty-nine eyes (49 patients) with a mean follow-up of 20.3 ± 3.27 months (range 6-48) were included. Thirty-one patients underwent full-thickness grafts for corneal perforation, and 18 underwent lamellar grafts for severe thinning. The most common indication was corneal thinning and/or perforation secondary to microbial keratitis (17 eyes, 34.7%). Anatomic success was achieved in 31 eyes (63.2%), in which no further surgical intervention was required for tectonicity. Functional success was achieved in 22 of 37 eyes (59.5%), where along with anatomic success, significant visual gain was also obtained. Absolute graft failure was noted in 12 eyes (24.5%), which developed recurrence of primary pathology requiring reintervention within the first 6 months. Good prognostic factor for success included sterile corneal perforations. The presence of microbial keratitis was noted to be a guarded prognostic factor for success.

CONCLUSIONS

Corneal patch graft can serve as a good therapeutic modality for corneal ulceration or thinning, not amenable to treatment with tissue adhesive application. Both anatomical success and functional success of 60% was achieved in our series. Those performed for immune-mediated conditions fared the best. Subsequent optical procedures may be performed for further visual rehabilitation at a later stage.

Case Series of Perforated Keratomycosis after Laser-Assisted In Situ Keratomileusis

Background

Fungal keratitis is an extremely rare complication of laser vision correction resulting in poor visual outcomes. Amniotic membrane transplantation should be kept in mind in eyes with corneal perforation prior to penetrating keratoplasty.

Aim

To assess the outcomes of multilayered fresh amniotic membrane transplantation (MLF-AMT) in patients with severe keratomycosis after laser-assisted in situ keratomileusis (LASIK). Study design. Hospital-based prospective interventional case series.

Methods

Five eyes of 5 patients were included in the study. All cases underwent microbiological scrapings from residual bed and intrastromal injections of amphotericin (50 mcg/mL), with flap amputation if needed, followed by topical 5% natamycin and 0.15% amphotericin. MLF-AMT was performed after corneal perforation. Later, penetrating keratoplasty (PK) was performed when corneal opacity compromised visual acuity. The outcome measures were complete resolution of infection, corneal graft survival, and best-corrected visual acuity (BCVA).

Results

The mean age of patients was 22 ± 1.2 years with 4/5 (80%) were females. The mean interval between LASIK and symptom onset was 8.8 ± 1 day, and the mean interval between symptom onset and referral was 14 ± 1.4 days. Potassium hydroxide (KOH) smears showed filamentous fungi, and Sabouraud's medium grew Aspergillus in all cases. Melted flaps were amputated in 4 (80%) cases. MLF-AMT was performed in all cases due to corneal perforation after a mean time of 12.4 ± 1.2 days of antifungals. In all cases, complete resolution of infection was seen 26 ± 1.8 days after MLF-AMT, and optical PK was done at a mean of 2.4 months later. No postoperative complications after MLF-AMT or PK were observed, with a 0% incidence of corneal graft rejection, and a final BCVA ranged from 20/20 to 20/80 after a mean follow-up of 14 ± 1.1 months.

Conclusion

MLF-AMT is a safe and valid option to manage corneal perforation during keratmycosis treatment to avoid emergency therapeutic keratoplasty.

LiQD Cornea: Pro-regeneration collagen mimetics as patches and alternatives to corneal transplantation

Transplantation with donor corneas is the mainstay for treating corneal blindness, but a severe worldwide shortage necessitates the development of other treatment options. Corneal perforation from infection or inflammation is sealed with cyanoacrylate glue. However, the resulting cytotoxicity requires transplantation. LiQD Cornea is an alternative to conventional corneal transplantation and sealants. It is a cell-free, liquid hydrogel matrix for corneal regeneration, comprising short collagen-like peptides conjugated with polyethylene glycol and mixed with fibrinogen to promote adhesion within tissue defects. Gelation occurs spontaneously at body temperature within 5 min. Light exposure is not required-particularly advantageous because patients with corneal inflammation are typically photophobic. The self-assembling, fully defined, synthetic collagen analog is much less costly than human recombinant collagen and reduces the risk of immune rejection associated with xenogeneic materials. In situ gelation potentially allows for clinical application in outpatient clinics instead of operating theaters, maximizing practicality, and minimizing health care costs.

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.

Amniotic Membrane as a Main Component in Treatments Supporting Healing and Patch Grafts in Corneal Melting and Perforations

Purpose

To report on surgical approaches using amniotic membrane applications and patch grafts in corneal melting and perforations. Anatomical and functional results, including advantages and disadvantages of the interventions, will also be explored.

Methods

A five-year retrospective analysis of 189 surgical treatments involving corneal melting with perforation was performed. In one evaluated treatment type, a graft of amniotic membrane, often folded one to three times, was sutured with the epithelial side facing the previously mechanically debrided corneal tissue. A larger monolayer amniotic patch was then sutured, with the epithelial side facing the top of the first membrane, to the perilimbal conjunctiva. For corneal patch grafts, the size-fitting technique of graft trephination was applied, and the donor-recipient junctions were sewn with interrupted sutures. All the procedures were evaluated, noting outcomes and complications of surgery, preoperative and postoperative visual acuities, postoperative intraocular pressures, graft rejection, and other late comorbidities and complications.

Results

We performed 119 amniotic membrane applications (63%) and 70 corneal patch grafts (37%). Anatomical reconstruction of the anterior chamber was achieved in 157 eyes, of which 102 eyes (86%) received an amniotic membrane and 55 eyes (79%) were treated with the patch graft technique. In 63 eyes (33%), more than one amnion or graft treatment was necessary to close the corneal perforation.

Conclusions

The success of medical and surgical management depends on the cause of corneal melting, and amniotic membrane applications often require further intervention; nevertheless, patch grafts deliver better tectonic reconstruction than amniotic membrane alone.

The use of dehydrated amniotic membrane allograft for augmentation of dural repair in transsphenoidal endoscopic endonasal resection of pituitary adenomas

BACKGROUND

In transsphenoidal endoscopic endonasal surgery (TEES), watertight separation of the sinonasal cavity and intracranial compartment is the primary goal of closure. However, even when meticulous closure technique is implemented, cerebrospinal fluid (CSF) leaks, dural scarring, and meningitis may result. Particularly when intraoperative CSF leak occurs, materials that facilitate the creation of a watertight seal that inhibits disease transition and minimizes inflammatory response after durotomy are sought. Dehydrated amniotic membrane (DAM) allograft appears to confer these attributes as studies have shown it augments epithelialization, facilitates wound healing, and minimizes and impedes bacterial growth. We detail the use of DAM allograft to augment sellar closures after TEES.

METHODS

We conducted a feasibility study, retrospectively reviewing our institution's database of TEES for resection of pituitary adenomas in which DAM was utilized to supplement sellar closure.

RESULTS

One hundred twenty transsphenoidal surgery cases with DAM were used during sellar closure, with a 49.2% intraoperative CSF leak rate. Of this cohort, two patients experienced postoperative CSF leak (1.7%), and no patients developed meningitis. CSF leak rate for TEES-naïve patients was 0.9%.

CONCLUSIONS

This feasibility study demonstrates that dehydrated amniotic membrane allograft can be safely utilized as an adjunct during sellar closures for TEES for pituitary adenoma resection with very low rates of CSF leak and meningitis.

How preparation and preservation procedures affect the properties of amniotic membrane? How safe are the procedures?

Human amniotic membrane (AM) has been widely used for tissue engineering and regenerative medicine applications. AM has many favorable characteristics such as high biocompatibility, antibacterial activity, anti-scarring property, immunomodulatory effects, anti-cancer behavior and contains several growth factors that make it an excellent natural candidate for wound healing. To date, various methods have been developed to prepare, preserve, cross-link and sterilize the AM. These methods remarkably affect the morphological, physico-chemical and biological properties of AM. Optimization of an effective and safe method for preparation and preservation of AM for a specific application is critical. In this review, the isolation, different methods of preparation, preservation, cross-linking and sterilization as well as their effects on properties of AM are well discussed. For each section, at least one effective and safe protocol is described in detail.

Scleral surgical repair through the use of nanostructured fibrin/agarose-based films in rabbits

Scleral defects can result as a consequence of trauma, infectious diseases or cancer and surgical repair with allogeneic scleral grafts can be required. However, this method has limitations and novel alternatives are needed. Here, the efficacy of acellular nanostructured fibrin-agarose hydrogel-based substitutes (NFAH) in the repair of scleral defects in rabbits was studied. For this, scleral defects of 5-mm diameter were made on 18 adult-male New Zealand rabbits and repaired with acellular NFAH, NFAH crosslinked with genipin (NFAH-GP) or glutaraldehyde (NFAH-GA), allogeneic scleral grafts as control (C-CTR) or not repaired (negative control N-CTR) (n = 3 each). Macroscopic and histological analyses were performed after 40-days. Macroscopy confirmed the repair of all defects in a comparable manner than the C-CTR. Histology showed no degradation nor integration in C-CTR while NFAH-GP and NFAH-GA biomaterials were encapsulated by connective and inflammatory tissues with partial biodegradation. The NFAH were fully biodegraded and replaced by a loose connective tissue and sclera covering the defects. This in vivo study demonstrated that the NFAH are a promising biocompatible and pro-regenerative alternative to the use of allogeneic cadaveric grafts. However, large defects and long-term studies are needed to demonstrate the potential clinical usefulness of these substitutes.

Therapeutic options to treat mustard gas poisoning - Review

Among the blistering (vesicant) chemical warfare agents (CWA), sulfur mustard is the most important since it is known as the "King of chemical warfare agents". The use of sulfur mustard has caused serious damages in several organs, especially the eyes, skin, respiratory, central and peripheral nervous systems after short and long term exposure, incapacitating and even killing people and troops. In this review, chemical properties, mechanism of actions and their effects on each organ, clinical manifestations, diagnostic evaluation of the actions triage, and treatment of injuries have been described.

Antimicrobial efficiency and stability of two decontamination solutions

Two decontamination solutions, commercially produced BASE•128 and laboratory decontamination solution (LDS), with analogous content of antibiotic and antimycotic agents, were compared in their antimicrobial efficiency and stability (pH and osmolarity). Both solutions were compared immediately after thawing aliquots frozen for 1, 3 or 6 months. Agar well diffusion method was used to test their antimicrobial efficiency against five human pathogens: Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis, Escherichia coli and Enterococcus faecalis. The difference in the inhibition of growth between the two decontamination solutions was mostly not statistically significant, with few exceptions. The most pronounced difference between the LDS and BASE•128 was observed in their decontamination efficacy against E. coli and E. faecalis, where the LDS showed to be more efficient than BASE•128. The osmolarity value of LDS decreased with cold-storage, the osmolarity values of the BASE•128 could not be measured as they were below the range of the osmometer. Slight changes were found in pH of the less stable LDS solution, whose pH increased from initial value 7.36 ± 0.07 to 7.72 ± 0.19 after 6 m-storage. We verified that BASE•128 and LDS are similarly efficient in elimination of possible placental bacterial contaminants and may be used for decontamination of various tissues.

The use of dehydrated amniotic membrane allograft for augmentation of dural closure in craniotomies and endoscopic endonasal transphenoidal surgeries

BACKGROUND

Primary watertight dural closure is the preferred method of postcraniotomy dural repair. However, even when ideal technique is implemented, postoperative infection, cerebrospinal fluid (CSF) leaks, pseudomeningoceles, and dural scarring are possible complications. For this reason, materials that augment the dura's ability to create a watertight seal, prevent disease transmission, and inhibit inflammatory response are sought. Dehydrated amniotic membrane (DAM) allograft appears to fulfil these requirements as it has several beneficial properties that aid wound healing, including promotion of epithelialization, scar tissue prevention, and inhibition of bacterial growth. We provide the literature's first description of the use of DAM allograft to supplement dural closures for craniotomies and transsphenoidal surgeries.

METHODS

We conducted a pilot study, retrospectively reviewing our institution's database of craniotomies and transsphenoidal surgeries that utilized DAM to augment dural closure.

RESULTS

One hundred fifty-five cases, including 102 new craniotomies for supratentorial lesions, one re-do craniotomy for supratentorial recurrent glioma, 18 craniotomies for infratentorial lesions, 1 craniotomy for anterior skull base schwannoma, 32 transphenoidal surgeries, and 1 combined craniotomy and transnasal endoscopic surgery, used DAM allograft to augment dural closure. Only one complication occurred (0.6% complication rate), which was a superficial wound infection requiring washout without craniectomy. No CSF leaks occurred.

CONCLUSIONS

This pilot study demonstrates that dehydrated amniotic membrane allograft can be safely utilized as an adjunct during dural closures for craniotomies and transsphenoidal surgeries.

Advances in perinatal stem cells research: a precious cell source for clinical applications

Perinatal tissues possess numerous types of stem (stromal) cells, which are considered effective candidates for cell therapy. These tissues possess common characteristics of both embryonic and adult stem cells, and cell therapists have begun to use perinatal stem cells to treat several diseases. Despite their benefits, these cells are considered biological waste and usually discarded after delivery. This review highlights the characteristics and potential clinical applications in regenerative medicine of perinatal stem cell sources - cord blood hematopoietic stem cells, umbilical cord mesenchymal stem cells, amniotic membrane stem cells, amniotic fluid stem cells, amniotic epithelial cells and chorionic mesenchymal stem cells.

Surgical management of peripheral corneal thinning disorders

The peripheral corneal thinning disorders are associated with degenerative, autoimmune, or infective causes. Corneal thinning can subsequently affect the visual acuity either by inducing severe astigmatism or by progressive involvement of the central cornea. In addition to this, the integrity of the eye is at risk. Medical management is necessary to address the underlying inflammatory or infectious causes; however, most of the cases require surgical intervention for tectonic support or for visual rehabilitation in patients with severe astigmatism. Preoperative investigations help in mapping the corneal curvature and thickness, thereby facilitating planning of treatment. Routine corneal transplantation techniques do not yield good results in peripheral corneal thinning disorders. Various surgical modifications have been described to manage these challenging cases. We review the available literature on causes and management of peripheral corneal thinning disorders.

The Use of Dehydrated Amniotic Membrane Allograft for the Augmentation of Dural Repair in Craniotomies

Background: In cranial neurosurgery, primary watertight dural closure is the standard method of post-craniotomy dural repair. However, cerebrospinal fluid (CSF) leaks, pseudomeningoceles, postoperative infections, and dural scarring are possible complications, even when a meticulous technique is implemented. For this reason, materials that enhance the dura’s ability to create a watertight seal, inhibit the inflammatory response, and prevent disease transmission are sought. Dehydrated amniotic membrane (DAM) allograft appears to facilitate these properties, as studies have shown that it improves wound healing, prevents scar tissue formation, promotes epithelialization, and inhibits bacterial growth. We detail the use of a DAM allograft to augment dural closures for craniotomies.

Methods: We conducted a pilot study, retrospectively reviewing our institution’s database of craniotomies that utilized DAM to supplement dural closure.

Results: A total of 122 cases, including 18 initial craniotomies for infratentorial lesions, 102 initial craniotomies for supratentorial lesions, one re-do craniotomy for supratentorial recurrent glioma, and one craniotomy for an anterior skull base schwannoma used a DAM allograft to augment dural closure. Only one complication occurred (0.8% complication rate), which was a superficial wound infection requiring washout without craniectomy. No CSF leaks occurred.

Conclusions: This pilot study demonstrates that dehydrated amniotic membrane allograft can be safely utilized as an adjunct during dural closures for craniotomies.

Tissue remodeling after ocular surface reconstruction with denuded amniotic membrane

Amniotic membrane (AM) has been widely used as a temporary or permanent graft in the treatment of various ocular surface diseases. In this study, we compared the epithelial wound healing and tissue remodeling after ocular surface reconstruction with intact amniotic membrane (iAM) or denuded amniotic membrane (dAM). Partial limbal and bulbar conjunctival removal was performed on New Zealand rabbits followed by transplantation of cryo-preserved human iAM or dAM. In vivo observation showed that the epithelial ingrowth was faster on dAM compared to iAM after AM transplantation. Histological observation showed prominent epithelial stratification and increased goblet cell number on dAM after 2 weeks of follow up. Collagen VII degraded in dAM within 2 weeks, while remained in iAM even after 3 weeks. The number of macrophages and α-SMA positive cells in the stroma of remodelized conjunctiva in the dAM transplantation group was considerably less. In conclusion, dAM facilitates epithelial repopulation and goblet cell differentiation, further reduces inflammation and scar formation during conjunctival and corneal limbal reconstruction.

Comparison of Collagen Cross-Linking and Amniotic Membrane Transplantation in an Experimental Alkali Burn Rabbit Model

PURPOSE

To compare the effects of collagen cross-linking (CXL) and amniotic membrane transplantation (AMT) on acute corneal alkali burns.

METHODS

After establishment of an alkali burn model, 32 rabbits were divided into 4 groups: control group, AMT group, CXL group, and AMT + CXL (combined) group. Clinical parameters, including epithelial wound, opacity, ulceration, and neovascularization, were evaluated on postinjury days 1, 7, 14, and 18. Histological parameters were examined in hematoxylin/eosin (H&E) and Masson trichrome-stained corneal sections. Immunohistochemical analyses, including a terminal deoxynucleotidyl transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling assay and cluster of differentiation 68 (CD68) labeling, were performed to determine the apoptotic index and macrophage activation.

RESULTS

On postinjury day 18, the epithelial wound of AMT {4.08% [interquartile range (IQR), 0.68%-5.22%]}, CXL [1.84% (IQR, 0.01%-3.89%)], and combined [3.44% (IQR, 0.01%-4.36%)] groups were significantly lower than the control [15.23% (IQR, 9.86%-23.06%)] group (P = 0.003). No significant difference was detected between the groups in terms of opacity (P = 0.303). Neovascularization was the least severe in the CXL group [16.18% (IQR, 8.39%-21.28%)] and the most severe in the AMT [34.47% (IQR, 17.71%-62.77%)] and combined [35.12% (IQR, 31.96%-59.98%)] groups on day 18 (P = 0.033). Significant increases in the apoptotic index and CD68 labeling were detected in the CXL and combined groups compared with those in the control group (P = 0.047 and P = 0.001, respectively).

CONCLUSIONS

CXL treatment is an effective adjuvant treatment for promoting reepithelialization, reducing inflammation and neovascularization, and preventing ulceration in acute alkali burns. Providing AMT after suppressing inflammation may be a more effective treatment.

Efficacy of self-retained cryopreserved amniotic membrane for treatment of neuropathic corneal pain

PURPOSE

Treatment of neuropathic corneal pain (NCP) remains intricate, and involves a long-term combined multistep approach. The self-retained cryopreserved amniotic membrane (PROKERA®, Bio-Tissue, Miami,FL) has been utilized for multiple ocular surface disorders. We evaluate the efficacy, safety, and tolerability of ProKera® Slim [PKS] and ProKera® Clear [PKC] in the treatment of NCP.

METHODS

Retrospective case series of 9 patients who received PKS/PKC for the acute treatment of NCP. Patient demographics, prior therapies, clinical examination, duration of PKS/PKC retention, changes in pain severity, corneal subbasal nerve density and morphology by in vivo confocal microscopy (IVCM; HRT3/RCM, Heidelberg Engineering, Heidelberg, Germany), and adverse events were recorded.

RESULTS

PKS/PKC were placed in 10 eyes of 9 patients. Pain severity improved by 72.5 ± 8.4% (from 6.3 ± 0.8 to 1.9 ± 0.6, scale 1-10, p = 0.0003) after retention for 6.4 ± 1.1 days. Despite shorter retention for 4.0 ± 0.7 days in patients with ring dysesthesia (4 eyes) or premature implant disengagement (2 eyes), pain severity still improved by 63.1 ± 12.5% (from 6.8 ± 1.0 to 2.4 ± 0.9, p = 0.009). During a follow-up of 9.3 ± 0.8 months, two patients reported recurrence of pain after 2.3 and 9.6 months respectively, treated effectively with additional PKS/PKC. IVCM showed a 36.6 ± 17.6% increase in total nerve density, from 17,700.9 ± 1315.7 to 21,891.3 ± 2040.5 μm/mm2 (p = 0.047), while the fellow PKS/PKC-untreated eyes did not show a significant interval change. Main nerve trunk and branch nerve densities were not statistically different. Dendritiform cell density decreased from 46.0 ± 8.2 to 32.0 ± 6.0 cells/mm2 (p = 0.01).

CONCLUSIONS

PKS/PKC provide a safe and effective treatment approach to achieve sustained pain control in patients with NCP.

Stromal lenticule transplantation for management of corneal perforations; one year results

PURPOSE

To study application of stromal lenticules extracted by femtolaser small incision lenticule extraction (SMILE) surgery as a surgical adjuvant to seal corneal perforations.

METHODS

Corneal stromal lenticules obtained through SMILE surgery with central thickness 100 μm or more were fixed over corneal perforation sites using 10-0 nylon interrupted stitches with an overlying single layer of amniotic membrane. Seven patients who had been followed up for a minimum of 12 months were assessed using slit-lamp biomicroscopy, fluorescein stain, tonometry, and best spectacle-corrected visual acuity (BSCVA) measurements. Postoperative complications were recorded throughout the follow up period.

RESULTS

Corneal perforations had successfully been sealed in all 7 patients; 3 patients (42.9%) exhibited improved postoperative BSCVA. During the follow-up period of one year, no signs of re-perforation or infections were detected in any patient.

CONCLUSIONS

These early findings suggest that the use of corneal stromal lenticules could be a safe and efficient surgical adjuvant for corneal perforation closure with potential clinical application, together with amniotic membrane, as relatively simple and low cost temporary measures to prepare perforated corneas for further definitive procedures.

Surgical outcomes of perforated and unperforated corneal descemetocele

OBJECTIVE

To compare the surgical outcomes of amniotic membrane transplantation (AMT) and penetrating keratoplasty (PK) in perforated and non-perforated corneal descemetocele.

METHOD

In this study, we retrospectively examined 48 eyes of 48 patients operated with AMT, and 32 eyes of 32 patients operated with PK for perforated and non-perforated descemetocele.

RESULTS

There were no significant differences between the two groups with regard to age, sex, laterality, follow-up duration, cause of descemetocele, and localization (p > 0.05). Thirty-six (75%) eyes in the AMT group and 17 (53.1%) eyes in the PK group were perforated prior to operation (p = 0.043). Surgical success was achieved in 35 (73%) of 48 eyes underwent AMT and 28 (87.5%) of 32 eyes underwent PK (p = 0.118). Perforation size was the only parameter significantly affecting surgical success (AMT p = 0.001, PK p = 0.003). The visual acuity was significantly better at the postsurgical period compared to the presurgical period in both groups (p = 0.003, p < 0.001). It was observed that the postsurgical change in the visual acuity score was significantly greater in the PK group (p = 0.001).

CONCLUSION

Penetrating keratoplasty is superior to AMT for achieving ocular surface integrity and enhancing visual acuity. Amniotic membrane transplantation saves time for patients and surgeons when donor cornea supply is limited and it allows PK to be performed at a quiet period when inflammation is suppressed.

Improvement of Amniotic Membrane Method for the Treatment of Corneal Perforation

In our retrospective study we evaluated the efficacy of an improved amniotic membrane (AM) roll-in filling technique (AMR) combined with multilayer amniotic membrane cover to treat corneal perforation and included 46 cornea perforations ≤ 3 mm in diameter treated with AMR and 20% C₃F₈ mixed gas filling of the anterior chamber. Anterior chamber depth, aqueous leakage, bubble maintenance time, and cornea morphology were monitored after each operation. The mean diameter of corneal perforation was 1.60 ± 0.55 mm (range 0.5–3) and the success rate of the AMR method for corneal perforation reconstruction was 100% after a single operation. Anterior chamber depth was normally reconstructed without AMR break-off, aqueous leak, or other complications. The mean time of the C₃F₈ gas bubble in the anterior chamber was 8.6 ± 2.0 days (range 4–12). At the last follow-up, all patients' visual acuity was improved to varying degrees. The mean follow-up time was 11.0 ± 5.6 months (range 3–36). The AMR plugging combined with multilayer AM cover is a secure and easy intervention, which led to 100% success in our study. Various perforations ranging from trauma to infection can be treated with AMR, which is especially practical in those countries where donor cornea availability is limited.

Partial-thickness corneal tissue restoration after a chemical burn

Purpose

We describe a case of full-thickness corneal restoration after an acute corneal burn with an acid agent.

Methods

A 32-year-old male reported painful discomfort, redness, photophobia, and a decrease in visual acuity in the left eye after a unilateral burn with an acid agent. Slit-lamp examination revealed massive corneal melting involving necrotic sequestrum of the entire corneal surface. Surgical approach was carried out in order to preserve residual ocular tissues.

Results

Extensive corneal–conjunctival layer curettage of the necrotic tissue was performed showing perfectly clear undamaged deep lamellar corneal layers. The patient underwent multilayered amniotic membrane transplantation and total capsular–conjunctival flap in order to preserve ocular tissue from further melting or corneal perforation. A complete and spontaneous “restitutio ad integrum” of the corneal layers was shown during the follow-up. The cornea was perfectly clear with restored normal anatomical architecture.

Conclusion

In this case, a spontaneous full-thickness corneal tissue restoration occurred after an acute chemical burn. Studies about the mechanisms whereby different cells interact and replicate within the stroma may unveil the biology behind corneal regeneration and transparency.

Morselized Amniotic Membrane Tissue for Refractory Corneal Epithelial Defects in Cicatricial Ocular Surface Diseases

Purpose

To evaluate the clinical efficacy of morselized amniotic membrane and umbilical cord tissue (MAU) in treating refractory corneal epithelial defect in ocular cicatricial diseases.

Methods

Retrospective review of four patients with ocular cicatricial diseases treated with topical MAU for corneal epithelial defects refractory to conventional treatments including topical lubricants, autologous serum, bandage contact lens, and tarsorraphy. Their symptoms, corneal staining, conjunctival inflammation, and visual acuity were compared before and after treatment.

Results

After topical application of MAU twice daily, two patients demonstrated rapid corneal epithelialization with prompt visual acuity improvement at the first day. All patients showed corneal epithelialization in 7.3 ± 2.6 days accompanied by a significant relief of symptoms, reduction of ocular surface inflammation, and improvement of visual acuity.

Conclusion

This pilot study suggests topical MAU can be developed into a novel treatment for treating refractory corneal epithelial defects.

Translational Relevance

Topical MAU can be an effective novel treatment for refractory corneal epithelial defects.

Long-term efficacy of glycerine-processed amniotic membrane transplantation in patients with corneal ulcer

PURPOSE

The aim of this study was to determine the long-term treatment efficacy of glycerine-preserved human amniotic membrane transplantation in patients suffering from corneal ulcers.

METHODS

This was a retrospective, non-controlled, monocentric analysis. Included were patients with corneal ulcers that were non-responsive to ointment or contact lenses and had been treated by amniotic membrane transplantation with either the overlay or sandwich procedure. Analysis parameters were visual acuity before and following treatment, recurrence rate and subjective comfort at the last follow-up.

RESULTS

Of the 371 amniotic membrane transplantations that were conducted, 135 surgical treatments in 108 patients (51.9% male, 48.1% female; mean age 63.7 years) met the inclusion criteria. In total, 99 overlay and 36 multilayer amniotic membrane transplantations were performed. The follow-up period was 47.5 ± 66.7 weeks (mean ± SD). The recurrence rate at the last follow-up was 47.8% with overlay membranes and 51.8% with the sandwich technique. There was no significant change in best-corrected visual acuity following treatment with overlays (p = 0.219) or sandwich procedure (p = 0.703). At the last follow-up, 72.1% (overlay) and 78.3% (sandwich) of the patients reported either no pain or increased comfort.

CONCLUSION

The recurrence rates and changes in visual acuity following overlay or sandwich amniotic membrane transplantation in patients suffering from corneal ulcer were lower than reported elsewhere in the literature. More than half of the patients profited from each of the amniotic membrane transplantation techniques with respect to recurrence and postoperative comfort.

Randomized trial comparing multilayer amniotic membrane transplantation with scleral and corneal grafts for the treatment of scleral thinning after pterygium surgery associated with beta therapy

PURPOSE

The aim of this study was to compare the use of multilayer amniotic membrane transplantation (AMT) with lamellar corneal transplantation (LCT) and lamellar scleral transplantation (LST) for the treatment of scleral thinning after pterygium surgery associated with beta therapy.

METHODS

Twenty-six eyes from 26 different patients with scleral thinning as a consequence of beta therapy after pterygium surgery were evaluated at the Federal University of São Paulo, Brazil. Ophthalmologic examination and ultrasound biomicroscopy were performed to assess scleral thinning before the transplant surgery and then repeated at 30, 90, and 180 days after surgery. An increase in scleral thickness, epithelialization of the ocular surface, and preservation of the ocular globe were the main outcome measures.

RESULTS

Irrespective of the surgical technique used (AMT, LCT, or LST), no clinical or statistical changes in corrected distance visual acuity were found in any of the patients during this study. The median preoperative scleral thickness was similar in all 3 groups: AMT = 0.45 mm, LST = 0.48 mm, and LCT = 0.52 mm (P = 0.257); however, 6 months after surgery, the median thickness in the AMT group (0.19) was significantly less than that of the LCT group (0.57) (P = 0.27) or the LST group (0.76) (P = 0.19). Epithelialization occurred in all the patients.

CONCLUSIONS

LCT was the best option for the structural treatment of scleral thinning, followed by LST with a conjunctival flap. A high rate of reabsorption was found with AMT, which was the least effective of the 3 therapeutic options and should not be used for this condition.

Delayed manifestation of bilateral scleral thinning after I-BRITE(®) procedure and review of literature for cosmetic eye-whitening procedures

Purpose

To report a case of delayed-onset bilateral scleral thinning and calcium deposition following a cosmetic ocular-whitening procedure (I-BRITE^®).

Methods

A 33-year-old male patient with a history of right-sided ptosis repair and left-sided anterior uveitis had previously undergone bilateral I-BRITE treatment for chronic conjunctival hyperemia. Four years after the procedure, the patient was referred to our institution with bilateral scleral thinning and overlying calcific depositions. A literature review was performed through PubMed from 1980 through 2014 using the search terms ‘cosmetic’, ‘ocular’, ‘conjunctivectomy’, ‘regional conjunctivectomy’, ‘I-BRITE’, ‘eye-whitening’, ‘scleritis’, ‘necrotizing scleritis’, ‘anterior uveitis’, ‘mitomycin C’, ‘5-fluorouracil’, and ‘bevacizumab’, along with associated cross-referencing from relevant articles.

Results

Examination of the patient revealed bilateral necrotizing scleritis within the nasal region of both eyes. Calcified plaques were also present within the areas of scleromalacia, along with epithelial defects demonstrated with fluorescein staining. Although evidence of previous intraocular inflammation was apparent within the left eye, there were no active signs of inflammation evident within either eye on initial presentation. Complication rates reported in the literature include: scleral thinning (1.8%), calcific plaque formation (2.9%), fibrovascular proliferation (13%), diplopia (1.2%), elevation of intraocular pressure (4.2%), and recurrence of conjunctival hyperemia (2.1%).

Conclusion

Cosmetic ocular whitening procedures have an attendant high complication rate, and have been associated with several adverse postoperative complications, which have in turn generated several reservations regarding the veritable benefit of the procedure. Many postsurgical complications may demonstrate delayed apparition, varying from several months to several years after primary surgical intervention as in the case reported here.